Unofficial translation
APPENDIX C2
MEASUREMENT REGULATION
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CONTENTS
ANNEX C2 ....................................................................................................................................................1
MEASUREMENT REGULATION ..............................................................................................................1
CONTENTS ..................................................................................................................................................2
MEASUREMENT REGULATION ..............................................................................................................4
Article 1. Scope .............................................................................................................................................................................. 4
METERING EQUIPMENT...........................................................................................................................5
Article 2. Metering Equipment - Metering Current ........................................................................................................................ 5
Article 3. Operator Competences ................................................................................................................................................... 5
Article 4. Metering Equipment Certification and Control .............................................................................................................. 5
Article 5. Metering Equipment Repair ........................................................................................................................................... 5
Article 6. Measurement Precision and Uncertainty ........................................................................................................................ 6
Article 7. Measurement Storage Supporting Equipment ................................................................................................................ 7
MEASUREMENTS .......................................................................................................................................8
Article 8. Magnitudes Measured – Measurement Units ................................................................................................................. 8
Article 9. Functionality Checks – Precision Testing ..................................................................................................................... 8
Article 10. Measured Magnitude Adaptation ................................................................................................................................. 8
Article 11. Lack of Reliable Information ....................................................................................................................................... 9
Article 12. Information Record Keeping ........................................................................................................................................ 9
Article 13. User Access to the Metering Equipment ...................................................................................................................... 9
Article 14. Measurement Management ........................................................................................................................................ 10
Article 15. Measurement Reports ................................................................................................................................................. 10
Article 16. Natural Gas Quantities Certification .......................................................................................................................... 12
Article 17. Measurement Standards ............................................................................................................................................. 17
Article 18. Analysis Standards (Gas Quality) .............................................................................................................................. 17
Article 19. Sampling Standards .................................................................................................................................................... 17
MEASUREMENTS - CALCULATIONS - CORRECTIONS....................................................................18
Article 20. Measurements & Calulations ..................................................................................................................................... 18
Article 21. Correction Methods .................................................................................................................................................... 18
Article 22. Calculation Methods .................................................................................................................................................. 18
METERING INSTRUMENTS ....................................................................................................................22
Article 23. General ....................................................................................................................................................................... 22
Article 24. Metering Instrument Definitions and Types ............................................................................................................... 22
Article 25. Main Metering Instrument Groups ............................................................................................................................. 23
Article 26. Temperature - Thermometers ..................................................................................................................................... 23
Article 27. Pressure – Pressure Gauges ........................................................................................................................................ 24
Article 28. Flow Meters ............................................................................................................................................................... 25
Article 29. Gas Chromatographs .................................................................................................................................................. 27
METERING PROCEDURES ......................................................................................................................28
Article 30. NGTS Metering Station Equipment ........................................................................................................................... 28
Article 31. Measurement Procedures ........................................................................................................................................... 28
Article 32. Exit Points .................................................................................................................................................................. 29
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CALIBRATION ..........................................................................................................................................30
Article 33. Equipment Calibration ............................................................................................................................................... 30
Article 34. Metering Equipment Calibration Frequency .............................................................................................................. 31
Article 35. Metering Equipment Calibration Procedures ............................................................................................................. 31
TABLES ......................................................................................................................................................34
TABLE Ι. Metering Equipment Checking ................................................................................................................................... 34
TABLE ΙΙ. Metering equipment calibration procedures ............................................................................................................... 34
TABLE ΙΙI. Calibration Equipment Standards ............................................................................................................................. 35
TABLE IV. Custody Transfer Instruments - (Measurement) Precision Standards - Procedures, Methods ................................ 36
TABLE V. NGTS Measurement Regulation Applicable Standards ............................................................................................. 39
TABLE VI NGTS Exit Points ...................................................................................................................................................... 41
TABLE VIΙ Future NGTS Stations .............................................................................................................................................. 41
FORMS ........................................................................................................................................................42
DAILY NG QUANTITY AND MEASUREMENT CHARACTERISTICS PROTOCOL AT ENTRY POINT ........................ 43
DAILY NG QUALITY COMPOSITION PROTOCOL AT ENTRY POINT ............................................................................. 44
MONTHLY NG QUANTITY AND MEASUREMENT CHARACTERISTICS PROTOCOL AT EXIT POINT ..................... 45
MONTHLY NG QUALITY COMPOSITION PROTOCOL AT EXIT POINT ......................................................................... 47
APPENDIX 2...............................................................................................................................................50
ENTRY POINTS .........................................................................................................................................53
EXIT POINTS .............................................................................................................................................55
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MEASUREMENT REGULATION
Article 1. Scope
The scope of the Measurement Regulation includes:

Natural Gas quantity metering and certification procedures

the description of the procedures and methods used to control and calibrate Metering Equipment,
including the Precision Standards considered in each case;

a brief description of the individual instruments of Metering Equipment, including their type and
specifications;

the terms and conditions under which the volume, Calorific Value, quantity and/ or any other
characteristic of the Natural Gas delivered to an Entry Point or received at an Exit Point by the
User are established in case of Metering Equipment fault or failure to provide measurements;

the procedures and conditions for settling disputes arising between the Operator and the User with
regard to issues concerning quantity measurements, Calorific Value calculations and the quality of
the Gas delivered and/ or received.
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METERING EQUIPMENT
Article 2. Metering Equipment - Metering Current
The Metering Equipment includes all metering and analysis instruments used by the Operator in
determining the quantity and analyzing the quality of the Natural Gas delivered to an Entry Point and
received at an Exit Point of the NGTS.
The Metering current includes the Metering Equipment for measuring the flow of uncorrected or
corrected volume and the entry of Natural Gas quality analysis data (composition), on a case to case basis,
for energy calculation purposes. Especially for Bus Natural Gas Refueling Stations (BNGRS), the
Metering current comprises a mass metering device using the Coriolis force method.
Article 3. Operator Competences
The Operator is responsible for supplying, installing, testing, maintaining, checking and certifying the
compatibility of the Metering Equipment as per the specifications listed in Tables ΙΙΙ, ΙV and V of this
Measurement Regulation.
Article 4. Metering Equipment Certification and Control
1. Each new Metering Equipment element shall undergo precision testing and functionality checks as
provided for in Article 9 hereof.
2. Any Metering Equipment instruments that go out of service due to fault shall be certified anew
prior to being reconnected for use.
3. The Operator shall run regular checks on the Metering Equipment at the frequency established in
Table I.
4. Each check of the Metering Equipment shall be run by the Operator or its authorized
representative. The User shall be entitled to be present during Metering Equipment checking if the
User requests so in writing. The User may report to the Operator any remarks regarding Metering
Equipment Checks. In no case may the User tamper with the Metering Equipment in any way.
5. Provided the Metering Equipment meets the specifications of Article 3 (1) hereof, the Operator
shall issue the respective check certificate established in Table Ι. The check certificate shall be
notified to the User.
6. Within five (5) days from the foregoing notification the User shall lodge with the Operator any
objections regarding the correctness of the information in the certificate, which objections shall be
considered in accordance with the terms on dispute settlement laid down herein.
7. Besides regular checks, the User may request from the Operator in writing Metering Equipment
checks at each Entry or Exit Point included in the Transmission Contract. The check shall be run
by the Operator following the User’s timely notice in writing, who shall be entitled to be present.
If the check results in that the Equipment operates within the predefined precision limits, the User
shall incur the cost of the check, otherwise such cost shall be incurred by the Operator.
Article 5. Metering Equipment Repair
The Operator shall be required to immediately set, repair or replace any Metering Equipment instrument
or other element which has suffered damage or fault or has ceased to operate, leading to non-compliance
of the Metering Equipment with the foregoing specifications.
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Article 6. Measurement Precision and Uncertainty
1. Definitions - Calculations
The Precision and Uncertainty of measurements are defined as follows:
Measurement Precision shall mean the proximity of a measurement to the mutually accepted reference
value for the magnitude measured. The term “precision” refers to uncertainty.
Uncertainty shall mean the quantitative ability of a metering system to give a value for a magnitude as
close as possible to the real value. Under ISO 5168 uncertainty is defined as “an estimate characterizing
the value range within which the real value is found”.
The real value shall mean the ideal value which is assumed to exist and which could have been known
had all sources of error been eliminated.
Uncertainty can be random and systematic.
A random measurement error shall be the deviation of a random measurement from the average value for
the magnitude measured. Random errors shall mean those errors that provide the observed fluctuation of
repeated measurements taken apparently under the same conditions.
A systematic measurement error shall mean the deviation of the average measurement from the real
value. Systematic errors shall be those that are introduced as a result of imperfections in the metering
instruments, their calibration or the metering technique used. Systematic errors are characterized by their
property to move towards one direction.
Therefore, for a small random error (small deviation), the precision of a measurement is considered to be
high, whereas for a big random error (big deviation) the precision of a measurement is considered to be
low.
The random Uncertainty, eR , of a measurement is defined as ±tσ , where σ the standard deviation of the
measurement and t the statistical value corresponding to the probability selected. To establish the value
for t we have used the “Student’s t test” method, and such value is equal to 2 for a confidence level of
95%. Hence random uncertainty is obtained from the following formula: (eR)95=±2σ. Standard deviation
N
is obtained from the formula σ=
 (x
i 1
i
 x) 2
(1) where:
N1
Ν is the number of measurements taken
x is the average value of individual measurements for a variable
xi is the value of one measurement for one variable (magnitude measured), e.g. Pressure P, Temperature
Τ, Energy Ε, etc.
Systematic Uncertainty, es , (bias) shall be the upper limit of the systematic error.
Hence the total Uncertainty for measurement U is obtained, under the international ISO 5168 (Table V)
standard, from the formula U= (eR )2  (es )2 (2) and expresses the interval (value range) within which it
is probable that the real value of the magnitude measured fluctuates with a confidence level of 95%.
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2. Individual Uncertainties of the metering system
This article refers to the individual uncertainties regarding the magnitudes measured, which contribute to
the overall uncertainty in the Energy of each metering system.
Uncertainty studies are classified in terms of the structure of the calculations of the magnitudes measured
depending on the meter type, as detailed below:
Α. System uncertainty in Energy for turbine meters
 Volume measurement uncertainty
 Pressure measurement uncertainty
 Temperature measurement uncertainty
 Uncertainty in the calculation of the compressibility factor and mathematical operation error
 Gross Calorific Value (GCV) measurement uncertainty
B. System uncertainty in Energy for orifice meters
 Differential pressure measurement uncertainty
 Pressure measurement uncertainty
 Temperature measurement uncertainty
 Orifice diameter uncertainty
 Metering current pipe diameter uncertainty
 Uncertainty regarding orifice diameter to pipe diameter ratio
 Discharge coefficient uncertainty
 Expansibility factor uncertainty
 Density measurement uncertainty (also under reference conditions)
 Gross Calorific Value (GCV) measurement uncertainty
The overall uncertainty U of the system with regard to Energy is calculated using formulas (1) and (2)
above in accordance with a relevant uncertainty study conducted by the manufacturing company.
For both types of meters, orifice and turbine meters, ISO 5168 is used in conjunction with ISO 5167.1991
(Table V).
In accordance with this article, the magnitudes measured (pressure, differential pressure, temperature,
flow volume, gross calorific value, energy, calculations, etc.) are considered acceptable when the
measurement readings are within the acceptable error limits for the magnitude measured, in accordance
with the relevant uncertainty study or the precision data for the metering equipment provided by the
manufacturing company. Where the measurement readings are within the acceptable error limits, then the
magnitude measured is adjusted as indicated in Article 10 “Measurement Management”.
Uncertainty studies are revised when part of the existing metering equipment changes or where the
international standards referring to the methodology of their calculations undergo radical changes.
Article 7. Measurement Storage Supporting Equipment
The magnitudes measured and calculated (qualitatively and quantitatively) by the metering equipment are
stored in electronic format in supporting storage equipment. Such storage units are located either in the
supervising computers or volume correctors (PTZs) of metering stations. The measurement files
generated are stored in the supporting equipment at least until the signature of the respective monthly
report.
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MEASUREMENTS
Article 8. Magnitudes Measured – Measurement Units
At the NGTS Entry and Exit Points constant measurements are taken for the magnitudes that regard the
Natural Gas quantity transmitted (mass, volume flow, density, pressure, differential pressure,
temperature), while in general sampling measurements and/ or analysis are run at regular time intervals
for magnitudes regarding the quality characteristics of the Gas. Where this does not apply, information is
obtained regarding Gas quality characteristics from neighboring NGTS Entry or Exit Points.
Table IV lists all measured or calculated magnitudes.
The measurement units for such magnitudes are listed in the same table, which lists among others custody
transfer, international standards and measurement precision.
The definitions of measurement units are given in the respective international standards, Law 3428/2005
(Government Gazette Issue No. 313/27.12.2005), as well as in the Transmission Contract.
Hourly, daily and monthly measurement information is kept for each Entry and Exit Point.
Article 9. Functionality Checks – Precision Testing
The Metering Equipment undergoes both functionality checks and precision testing.
Functionality checks shall mean all those checks run by the Operator's personnel at regular intervals
aiming to ensure the satisfactory operation of the Metering Equipment and in general of the supporting
equipment of metering stations.
Alarms received at the Operator’s Supervisory Control and Data Acquisition (SCADA) System and
which are due to abnormal states of the Metering Equipment and/ or the metering station shall constitute
grounds for running checks, including but not limited to emergency functionality checks.
Precision Testing shall mean those checks run by the Operator’s specialized personnel following
information received by the User at regular intervals for which provision is made in the Measurement
Regulation or the instructions of the equipment manufacturers or agreed upon with the User. Unscheduled
precision tests shall be following a fault or suspicion of fault in the Metering Equipment. The User shall
be entitled to be present during Metering Equipment Precision Testing.
The reference information for all checks and tests shall be kept by the Operator for the period provided
for in Article 12.
The Tables in Appendix 2 list all the information for the Metering Equipment elements of the NGTS
metering stations. Metering stations are sorted at Entry and Exit Points. The same table also lists the
anticipated precision for energy metering for each station as has been calculated following relevant
uncertainty studies (Article 6), which take account of the installation details (listed in the same table) and
the recorded permissible error limits of individual instruments (overall possible error). Such limits and
overall uncertainties for the Metering Equipment in conjunction with the uncertainty of the (working)
reference standards establish the limits above which arrangements shall be necessary during the
calibration of the Metering Equipment performed after Precision Testing.
Article 10. Measured Magnitude Adaptation
1.Where following a check the precision of the Metering Equipment at an Entry or Exit Point is found to
be outside the permissible error limits, the value of the respective Measured Magnitude, as this has been
measured shall be adapted by use of calculations, the algorithms of which are based on international
standards (Table V) to minimize the Metering Equipment error.
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2.Where para. 1 hereof applies, the erroneous values of the Measured Magnitude throughout the period
during which it is demonstrated that the precision of the Metering Equipment had been outside the
permissible limits, shall be replaced by the corrected values.
3.If it is not found with certainty that the date of commencement of the period described in point 2 above,
as such shall be considered either the first day of the second half of the period from the last check on the
Metering Equipment or the date of the last admissible measurement based on the Delivery - Offtake
Reports or on the last admissible check. A criterion for the selection shall be the date starting on which
the time period needed to adjust the measurements outside the permissible limits is shorter.
4.Where points (1), (2) and (3) of this Article apply, the Operator shall adjust accordingly the Final
Dispatch to Users and the charges to which this leads. The relevant adjustment shall appear in the next
invoice issued by the Operator to each User.
Article 11. Lack of Reliable Information
In case of failure to take reliable measurements or in case of occasional interruption of the operation of
the Metering Equipment at an Entry or Exit Point, the Operator may following consultation with the
Users, on the reasons why such Point is an Entry or Exit Point under their respective applicable
Transmission Contracts calculate an estimate of the Natural Gas quantity which is delivered or received
through such Metering Equipment. For the purpose of this calculation, particular use is made of reliable
measurements taken by the Metering Equipment at the given Entry or Exit Point under similar conditions
during the respective time periods in the past.
Article 12. Information Record Keeping
1.The Operator shall keep record of all measurement information regarding Metering Equipment for at
least two (2) years after their taking
2.The Operator shall also keep record of all testing and calibration information regarding Metering
Equipment for at least five (5) years after their performance.
Article 13. User Access to the Metering Equipment
1.Each User or User authorized representative shall be entitled to access to the Metering Equipment at
each Entry or Exit Point in the Transmission Contract, submitting a request in writing to the Operator at
least 3 days prior to the desired visit date. In such request, the User must indicate the date on which it
wishes to make such visit, the estimated duration of the visit, the number of visitors, and the reason for
which it requests such visit.
2.The Operator may reject the User’s request if the Operator considers that there are reasons rendering the
visit impossible on the date requested by the User. In that case, in concert with the User, the Operator
shall appoint a new visit date.
3.The User's visit shall be made under the supervision and guidance of the Operator specialized
personnel. The User must take all necessary measures to avoid causing damages to the equipment and
comply with the instructions and advice of the Operator personnel.
4.The User shall be exclusively liable for its personnel and representatives participating in the visit. The
Operator’s personnel may refuse entry to or request exit from the Metering Equipment space to all or
part of the visitors where for any reason they consider that there is risk for the safety of the people or
equipment in such space.
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Article 14. Measurement Management
1.Measured Magnitudes are collected by the Metering Equipment and managed by the Measurement
Management System - MMS (where available). It is pointed out that in general the MMS is not
available for Type B exit points (see Article 32). A MMS installed at a NGTS Entry or Exit Point
typically performs the following functions (where these are available) :

it sums up the respective quantities (energy, volume, mass) for all metering currents;

it checks and transfers the suitable chemical composition quality analysis to the flow calculator;

it calculates the required quantities for the reports (under both operating and reference conditions)
and generates reports on a daily (hourly analysis) and monthly (daily analysis) level;

it stores the magnitudes measured and calculated (qualitatively and quantitatively) in record at
least until the signature of the respective monthly reports;

it ensures the integrity of the above records and records any changes to them;

it provides a safe access mechanism for the possibility of changes to the station measurement
parameters;

it communicates with the Operator's Supervisory Control and Data Acquisition system
transmitting measurement and state data or accepts commands as is provided for in the basic
design of the Supervisory Control and Data Acquisition system.
The records generated by the system are used in the generation of reports as are or following conversion
to the reference units required by them, as the case may be.
2.The reliable operation of the MMS is checked periodically or when requested by the User at the
responsibility of the Operator and in the presence of the User or its representative. The items checked
included but are not limited to the following:

correct recording and management of the magnitudes measured;

precision of the magnitudes calculated;

completeness and precision of the reports generated.
3.Each User is entitled to receive a copy of the measurement reports concerning each Point where such
User receives or delivers Natural Gas. Copies are generated by specialized Operator personnel, who
take all necessary measures to avoid causing damages to the metering equipment and the measurement
record.
Article 15. Measurement Reports
The Measured Magnitudes obtained from the Metering Equipment at each Entry or Exit Point are used to
prepare the Measurement Reports. Where a Measurement Management System is not available, such
reports are prepared on the basis of indications or reports obtained by the Metering Equipment.
Metering Reports are prepared by the Operator for each Entry and Exit Point and are also signed by the
users who use the specific Points. Based on the Measurement Reports, the Quantity and the quality
characteristics of the Natural Gas delivered to an Entry Point or received at an Exit Point of the NGTS are
established.
15.1 Entry Point Reports
By 13:00 hours each Day, the Operator shall prepare the following Reports for each NGTS
Entry Point regarding the natural gas quantities that have been received on the previous Day:
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15.1.1 Daily NG Quantity and Measurement Characteristics Report at Entry
Point (Form 1)
Such report shall include the following magnitudes:
i. the overall delivered NG volume (VΝ) in Nm3
ii. the overall delivered NG energy (E) in MJ
iii. the Gross Calorific Value (GCV) in MJ/Nm3
iv. Pressure (P) in bara
v. delivery Temperature (T) in οC
vi. Relative Density rd
vii. the Wobbe index in ΜJ/Nm3
viii. the overall hydrogen sulphide (H2S) content of the NG in mg/Nm3
ix. the overall sulphur (S) content of the NG in mg/Nm3
x. the Water Dew Point in οC under reference conditions
xi. the Carbohydrate Dew Point in οC under reference conditions
If magnitudes (iii) to (xi) are measured constantly, the Report shall indicate their weighted
average. If such magnitudes are measured at regular intervals, the Report shall indicate the
arithmetic average of at least three measurement readings during the Day.
Especially with regard to the Aghia Triada Entry Point, magnitudes (νiii) to (xi) inclusive are
not measured.
15.1.2 Daily NG Qualitative Composition Report at Entry Point (Form 2)
Such report includes the Natural Gas % mole in terms of carbohydrates (C xHy), carbon
dioxide (CO2), nitrogen (N2) and oxygen (O2).
15.2 Exit Point Reports
For each Metering Station of NGTS Exit Point which is an Exit Point declared by the User in
accordance with Annex Α2, the OPERATOR's personnel shall prepare the following reports at
the latest by 14:00 hours on the sixth (6th) calendar day of each month:
15.2.1 Monthly NG Quantity and Measurement Characteristics Report at a
Metering Station Exit Point (Form 3)
Such report indicates for each metering current of the Station and per day of the given
Contractual Month the overall NG volume delivered (VΝ) in Nm3, the overall NG energy
delivered (Ε) in MJ, the Pressure in bara and the delivery Temperature in οC. It also indicates
the sum of the delivered volume of NG (VΝ) in Nm3 and the sum of the NG energy delivered
(Ε) in MJ, for all metering currents of the given Metering Station.
15.2.2 Monthly NG Qualitative Composition Report at a Metering Station Exit
Point (Form 4)
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Such report includes the Natural Gas % mole in terms of carbohydrates (C xHy), carbon
dioxide (CO2), nitrogen (N2) and oxygen (O2). It shall also indicate the Gross Calorific
Value (GCV) in MJ/Nm3, Relative Density rd and the Wobbe index in ΜJ/Nm3. For all
Type B Exit Points (see Article 32) which do not have a gas chromatograph, the above
information shall be obtained from a neighboring Entry or Exit Point with a gas
chromatograph.
15.3 Natural Gas Latent Quantities Report (Form 5)
1.Natural Gas Latent Quantities shall be the Quantities that regard:

Own consumption of Natural Gas (station A/C, Boilers, Dehumidification Units)

Natural Gas Losses due to maintenance works, function tests or necessary discharges

Corrections to the Magnitudes Measured due to equipment calibration, wrong readings
or other causes.
2.By the sixth (6th) calendar day each Month, the Operator shall prepare for each Entry and
Exit Point of the NGTS a Natural Gas Latent Quantities Report indicating for each Day of
the previous Month the volume (VN) in Nm3, the Energy (Ε) in MJ and the Gross Calorific
Value (GCV) in MJ/Nm3 for the Natural Gas Latent Quantities.
Article 16. Natural Gas Quantities Certification
16.1 Report Signing
1.The Entry Point Reports shall be signed by the Operator and the Users for which the given
Entry Point is a declared Entry Point at the latest by 14:00 hours on the day following the
Contractual Day to which they refer.
2.Monthly Reports as well as Latent Quantities Reports at an Exit Point shall be signed each
month by the Operator and the Users for which the given Exit Point is a declared Exit Point
at the latest by 14:00 hours on the seventh (7th) day of each calendar month.
3.In case of disagreement on the part of any one of the Parties with regard to the
contents of the Measurement Reports, such disagreement shall be entered as a note in
the Report, the Report shall be signed by the Parties and shall be considered
temporary until the final settlement of the dispute, in accordance with the provisions of
Clause 16 of the Transmission Contract.
4.For any dispute that may arise between the Parties with regard to the measured NG
quantities or its characteristic magnitudes, the User or the Operator who believes to be
affected shall inform in writing the other Parties that have a lawful interest in the Point
involved in the dispute. An objection lodged by any party on any of the above shall not hold
such party or the other Parties free from their obligations arising from the respective
Contracts entered into by and between them.
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5.Where one of the Users or the Operator is unable or refuses to sign any Report invoking
reasons of Force Majeure, the provisions of Article 10 of the Transmission Contract shall
apply.
6.Any revisions of the Quantity Certifications that have arisen following the implementation
of the provisions under points (3) and (4) of this Article shall only affect the values of the
magnitudes that have been calculated using the revised values of such Reports. In that case,
a settlement for all revised magnitudes shall be performed at the end of each calendar Month
and the relevant sum shall be paid in fully with the immediately following invoice.
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16.2
Expert
1. In case of disputes that arise with regard to measurement issues, the Parties shall undertake to
make all possible endeavors to amicably settle such disputes in accordance with the provisions of
clause 16.3 of the Transmission Contract. Where the settlement procedure has not been completed
within thirty (30) days from the dispatch of the invitation for amicable settlement, the Parties may
agree to take the disputes on measurement issues to be settled to a mutually accepted Expert.
2. Next is given the procedure followed to appoint the Expert:
a. the party that wishes for an Expert to be appointed shall notify such intention to their
counterparty, providing in that notice details of the issue which such first party suggests
that it be resolved by the Expert;
b. the Parties shall meet in order to reach an agreement with regard to the issue that needs to
be resolved, as well as to the person to be appointed Expert;
c. where the Parties have not reached an agreement on the person to be appointed Expert
within twenty one (21) Days from the service of the initial notice, then the Parties shall
immediately bring such issue to the NETHERLANDS METROLOGY INSTITUTE
(N.M.I), which shall appoint the Expert; the contact information of this Institute is:
Nederlands Meetinstituut
Postbus 394
3300 AJ Dordrecht (NL)
Hugo de Grootplein -1
BG Dordrecht
Tel:+31 78 332332
Fax +31 78 332309
d. if an Expert is mutually agreed or appointed, the Parties shall immediately and jointly
notify to the Expert the appointment of the latter and ask the Expert to confirm within
seven (7) Days from offtake of the notice whether the Expert wishes and is able to accept
their appointment and under which conditions, which must be in line with the conditions
under point 4e below; where such notice is not jointly made within fourteen (14) Days,
either one of the Parties may serve a notice on behalf of both Parties to the Expert, also
notifying such notice to the other party;
e. if the Expert does not wish or is unable to accept the appointment or has failed to confirm
acceptance of their appointment within twenty one (21) Days from the notice, then, unless
the Parties agree to appoint another Expert, any one of the parties may refer the issue to the
NETHERLANDS METROLOGY INSTITUTE (N.M.I), of which it shall be requested to
make a new appointment and the procedure shall be repeated until an Expert is found that
accepts their appointment;
f. each party shall cooperate with their counterparty in order to agree on the person to be
appointed Expert and further, to negotiate and agree on the terms of and the
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implementation of the agreement on Expert appointment, which shall be signed by both
parties;
g. the Expert may not be a person who:
(i)
does not possess the educational and experience qualifications to issue an
opinion on the issue; and/ or
(ii)
at the time of their appointment (or within three (3) months prior to such
appointment), that same person or a blood or kinship relative of direct stirpes
or lateral linearity, and up to the second degree inclusive, is Director,
executive, or employee of any one of the Parties or of an Associated
Company of any one of the Parties; and/ or
(iii)
at the time of their appointment, the Expert or a blood or kinship relative of
direct stirpes or lateral linearity, and up to the second degree inclusive has
been hired directly or indirectly as consultant by either one of the Parties or
any Associated Companies of the Parties.
3. The Expert's fees shall be agreed upon by the Parties and paid by the Party who results to be
wrong. Where both Parties are proven wrong the Expert’s fees shall be paid by both of them on a
50-50 basis.
4. Further, the following are agreed:
a. all information, data, and documents notified or delivered by one party to the Expert as a
result of or in relation to the appointment of the latter, shall be considered confidential, and
the Expert must return them to the party having furnished them by the end of the
procedure; the Expert may notify any of the above information, data or documents to the
Expert’s employees or Associated Companies which have the same obligations as the
Expert, and which in case of violation shall be jointly liable with the Expert vis-à-vis the
affected Party;
b. next is given the procedure followed for referring an issue to the Expert:
(i)
the Expert must within fourteen (14) days at the latest from their appointment
summon the Parties to a meeting where the Expert shall lay all issues that
need clarification, as well as the procedural rules to be applied, and which
must be in line with the terms and conditions of this article;
(ii)
the Parties shall be able to provide information and details and expose their
arguments to the Expert;
(iii)
the Parties shall be required to provide the details and information and submit
their arguments as soon as possible and in any case within forty five (45)
days from the appointment of the Expert; the Expert shall not consider
details, information and arguments that have been submitted past the forty
five (45) day deadline, unless such details, information and arguments have
been furnished in response to specific requests of the Expert;
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(iv)
each Party shall incur the expenses required to provide all the details,
information and arguments given by such Party, as well all expenses that
regard the witnesses and persons appointed by them;
(v)
all communication between the Parties and the Expert must be in writing and
copies must be served to the respective counterparty; no meetings between
the Expert and any one of the Parties may be held if both Parties have not
been invited on time at least two (2) days in advance to attend such meeting;
(vi)
the Expert’s decision must be in writing, detailed and fully justified and must
be issued within three (3) months from the appointment of the Expert, unless
the Parties agree otherwise.
c. if the Expert fails to issue a decision within the time limits established above, then any one
of the Parties may by their declaration establish a deadline not later than thirty (30) days,
by which the Expert must issue their decision, or else the Expert shall cease to have any
competency and be required to refund the fees; a decision of the Expert that may be
issued past the foregoing thirty (30) day deadline shall be null and void;
d. the Expert shall not be considered arbitrator but shall issue the required decision as Expert
and the provisions on arbitration shall not apply to the Expert, the Expert's decision or the
procedure required for the issue of the decision;
e. the Expert’s decision shall be final and binding upon the Parties. The Parties shall not
bound by the Expert's decision only where following Arbitration it is found that such
decision had been a product of fraud or material fallacy with regard to the actual facts;
otherwise the Expert's decision shall constitute unquestionable evidence with regard to the
issues it pertains to.
5. Regardless of the foregoing procedures, the Parties must continue to always fulfill their
contractual obligations irrespective of the nature of the dispute and although the dispute has been
referred for settlement in accordance with this Article.
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MEASUREMENT RULES & STANDARDS
Article 17. Measurement Standards
The Measurement Standards listed in Tables ΙV and V of this Measurement Regulation establish among
others:
1.the metering methodology used to measure the volume or mass of Natural Gas with specific
composition, pressure, and temperature by a suitable meter;
2.the dimensions, the manufacturing and installation methodology, and the operating conditions for
the Metering Equipment;
3.the methodology and the calculations required to establish the volume and the Gross Calorific Value
of the measured Natural Gas quantity;
4.the range and precision of each measurement and the meter calibration methodology;
5.the methodology used for the required testing for each Metering Equipment element.
Article 18. Analysis Standards (Gas Quality)
The Analysis Standards listed in Tables ΙV and V hereof establish among others the Natural Gas sample
analysis procedure in accordance with the Gas Chromatogram principle. More specifically they shall
establish the Natural Gas sampling method, the metering methods, the ingredients of the sample to be
analyzed, as well as its required characteristics, the measurement range for each ingredient, the precision
of the measurement and checks on the measurement results, as well as analysis traceability.
Analysis at the chromatograph concerns nitrogen, carbon dioxide, saturated carbohydrates up to six
carbon atoms. Further, certain sulphur compounds are established at another chromatograph. In addition,
Natural Gas may also contain other elements such as oxygen, methanol, carbohydrates with a higher
number of carbon atoms, water, etc. at such small quantities that do not affect the precision of the method.
Article 19. Sampling Standards
ISO 10715 provides instructions on the collection, keeping and management of representative constant
flow Natural Gas samples. It also provides instructions on the sampling strategy, the position of the
sampling probe, and the design of the sampling equipment.
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MEASUREMENTS - CALCULATIONS - CORRECTIONS
Article 20. Measurements & Calculations
20.1
Volumetric Flow Measurement
This is the continuous measurements of the gas or LNG that passes through a pipeline cross
section for a given time period.
20.2
Speed Measurement
This is the determination of the speed of the gas or LNG at a given point of the flow pipeline
cross section. It is used to establish the flow profile. The Point where the average speed of
flow is determined is used by volume meters.
20.3 Mass Measurement
Such measurement is taken using the following methods:
(a) establishing the Coriolis Force
(b) establishing volumetric flow and density
(c) establishing volumetric flow, pressure and temperature
(b) by weighing (acontinuous method).
20.4
Gross Calorific Value Calculation
This is calculated by determining the quantitative analysis of the Gas sample using the Gas
Chromatography analyzer chromatogram using the procedure detailed in Article 22.1 hereof.
When the chromatogram represents all sample components, the results are normalized,
accepting that the fraction of the total surface area of each peak is the same with the
percentage ratio of the component in the sample.
20.5 Energy Calculation
The energy of the passing gas (MJ) is calculated on the basis of the calculated Gross Calorific
Value of the gas and its volume.
Article 21. Correction Methods
Using these methods it is possible to compensate systematic errors of meters connected to flow
calculators. This is achieved by drawing on the meter calibration certificates under conditions similar to
those of their operations. Such a method is typically the volumetric flow correction method with linear
interference in relation to the percentage of the meter maximum volume flow.
Article 22. Calculation Methods
22.1 Gas chromatograph
The gas chromatograph determines the gas composition.
The gas components determined are:
 Methane C1
 Ethane C2
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 Propane C3
 Isobutane i-C4
 Regular butane n-C4
 Isopentane i-C5
 Regular pentane n-C5
 Hexane and heavier carbohydrates C6+
 Nitrogen N2
 Carbon dioxide CO2
During each analysis the gas chromatograph carries out the following calculations in
accordance with ISO 6976 (Tables IV and V):
 Gross Calorific Value at reference conditions
 Relative density
 Density under reference conditions
The supervising computer receives each gas analysis from the gas chromatographs and
calculates the average values of the above gas parameters on an hourly and daily basis.
The following also apply:
i. the last analysis received is acceptable provided it meets the criteria established in the
supervising computer and the chromatograph is in normal operating condition;
ii. the chromatograph periodically carries out calibration gas analysis, either automatically
or manually. The response factors for each component between two successive
calibration analyses are checked. The discrepancies between them must be within the
levels established under ISO 6974 (Tables IV and V).
iii. the gas analysis to be used is established on the basis of priority procedures for each
point. When so required, the priority procedure is agreed upon with the Users at regular
intervals;
iv. the analysis average values are computed on at least a daily basis.
22.2 Flow calculators and Supervising Computers - PTZ Correctors
The volume of the gas consumed is calculated separately for each meter run by the respective
flow calculator.
Flow calculators are designed to calculate the flow of energy and gas volume, considering the
signals from the respective meter run metering device, the temperature, pressure, differential
pressure transmission instruments, and the overall chemical analysis (using the supervising
computers). More specifically flow calculators:
 calculate the gas volume (m 3 ) and volume flow rate (m 3 /h) at meter run pressure and
temperature (with regard to turbine meters, ultrasonic flow meters, rotary positive
displacement meters, and orifice meters);
 calculate the gas volume (m 3 ) and volume flow rate (m 3 /h) following the application of
the error correction equation for the respective meter (turbine, ultrasonic flow meters) to
the meter run pressure and temperature;
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 calculate the gas volume (Νm 3 ) and volume flow rate (Νm 3 /h) under normal pressure
and temperature conditions (reference conditions);
 calculate gas compressibility under ISO 12213 (Table V) for meter run temperature and
pressure conditions and the composition detected by the chromatograph;
 calculate the energy of the passing gas (MJ) and the energy flow rate (MJ/h) on the basis
of the calculated Gross Calorific Value of the gas and its volume.
All data generated by flow calculators are real billing data which are stored and processed by
the supervising computer.
At the Station there may be installed two identical supervising computers to ensure 100%
reserve. Supervising computers supervise flow calculators and chromatograph computers.
Each supervising computer processes the results and calculates hourly values.
All of the above results are stored in the respective folders in the flow calculator. Pressures,
temperature, differential pressure, compressibility, as well as other real time data are
constantly updated to allow for the calculations of flow averages carried out by the supervising
computer.
The principal role of each flow or supervising computer is to collect gas flow data from the
connectors at meter runs, meters or transmitters, and calculate the volumetric flow under
reference conditions, as well as energy flow. Flows are completed with hourly, daily and
overall sums.
It is pointed out that at certain type B Exit Points (cf. Article 32) instead of flow and
supervising computers there is only a type PTZ corrector which calculates and stores the
hourly, daily and monthly volume flow values (Nm3). The Operator calculates the energy by
using the Gross Calorific Value from the available chromatograph data at a neighboring point.
22.3
Volume calculation method under reference conditions for turbine,
ultrasonic flow and rotary positive displacement meter runs.
Using such meters, gas supply is measured at operating pressure and temperature. To have a
common reference base, such measurements are reduced to reference conditions. Such
calculation uses the ΡΤΖ method. In accordance with such method, the following formula is
used to convert the volume measured to reference conditions:
Vb  Vm 
Pm b  b


Pb m  m
Where
Ρ: gas pressure,
Τ: absolute gas temperature,
V: gas volume,
m: measurement state,
b: reference state
Compressibility factor Ζ depends on the composition of the gas and the pressure Ρ and
temperature Τ conditions. For ΡΤΖ correctors a fixed gas composition is taken (fixed Zb),
hence Zm is calculated for the existing Pm, Tm conditions. The remaining magnitudes are
received by the corrector by direct metering (Vm, Pm, Tm). In this way corrected supply Vb is
calculated.
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In this case, the chemical composition, Gross Calorific Value and relative density data are
received by the chromatograph that is installed at the nearest metering station.
The corrected PTZ volume calculation method can apply either using a PTZ corrector,
or by the flow calculator using pressure and temperature transmitters.
22.4 Volume calculation method under reference conditions for orifice meter
runs.
This method is based on measuring the differential pressure that develops before and after
the orifice meter on the fluid characteristics and under the conditions in which the meter is
used. Orifice meter manufacturing, installation and use characteristics are established in
accordance with ISO 5167 (Tables IV and V). Using data such as pressure P, temperature T,
fluid density ρ, differential pressure ΔP the flow of the mass Qm that enters the time unit
through the orifice is calculated. Next, using such value with gas density ρ volume flow Q
under operating (real) conditions is calculated, whereas normal volume flow Qn or volume
flow under reference conditions is calculated also using density under reference conditions
ρn. The above densities are measured either directly using densimeters, or under ISO 6976
(Tables IV and V) using gas chemical composition (ρn calculation), pressure, temperature,
and compressibility (ρ calculation).
22.5
Volume calculation method under reference conditions for mass meter
runs.
In this case, first the mass flow is determined, and then using density under reference
conditions, volume flow under reference conditions is calculated.
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METERING INSTRUMENTS
Article 23. General
Metering instruments play an important part in the operation of the systems incorporated in the natural
gas transmission network. Variables such as gas pressure, temperature, and flow are highly important
parameters in the processes that take place at all Points of the network in general.
Such variables are measured by special instruments which are installed at Metering and Regulation
stations, as well as at other Points in the network. So, the entire system is managed using these
measurements of variable parameters by special metering instruments, either locally or even
telemetrically, gas quantities to users are reduced to the final pricing form, the smooth operation of the
system is checked constantly, the quality of incoming gas is checked, and basically the entire operation is
carried out with due supervision and checks in a valid and efficient manner.
Article 24. Metering Instrument Definitions and Types
The term instrument shall mean a sensitive electrical or mechanical or pneumatic or digital variable
parameter measuring, transmitting, or checking device, which is installed in the NGTS and is connected
to the measurement process devices and parts. The various types of metering instruments may be
classified depending on the type of measurements they take. Therefore, depending on the type of
measurements taken, such instruments fall mainly under three categories, these are:
24.1 Indicating Instruments
Indicating Instruments measure and record the instant value of a variable basically relating
to the measurement process and it is not necessary to store or record it in analog or digital
format. Such instruments include: analog or digital manometer (pressure gauge), thermometer
(measurement gauge), etc.
24.2 Data Loggers
Data Loggers are the instruments used to permanently or partially record the variable
parameters of a process, aiming at the systematic recording of operating data necessary for
the Operator to proceed to study and further analysis. In essence, such instruments, if analog,
record on a paper surface (calibrated depending on the use) changes to the operating
parameter in time. Digital data loggers record measurement data, depending on the desirable
settings, in a digital memory from which they can be retrieved using a computer and be
analyzed using suitable software. In this way and by using data loggers, the Operator of a
system is able to store the various operating data for their required processing and for future
use. Such instruments are used in many transmission system operation applications (e.g.
metering data for gas pricing at delivery Points).
24.3 Summing Instruments
Summing Instruments which are also called meters (analog-mechanical or digital) record
the overall value of an operating variable for a given time period, during which the instrument
or the metering device for a given parameter had been operating. Such summing instruments
which are widely used in the natural gas system such are for instance: the instrument
recording the overall volume of the natural gas that has passed through a turbine meter or
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other type of meter during a certain period at the reference system Metering and Regulation
stations.
The various metering instruments fall under the following two categories depending on whether they
serve or not billing purposes:
24.4 Supervising Instruments
Supervising instruments aim at recording the instant value of a parameter in order to ensure the best
supervision of the NGTS without such value being used for User billing purposes. Such instruments
are for instance analog manometers.
24.5
Custody Transfer Instruments
Custody Transfer Instruments are those NGTS instruments that are used for
Custody Transfer purposes under international standards, procedures and methods as
laid down in Tables IV and V. These are accompanied by calibration certificates and are
checked and/ or recalibrated either by special metrologic laboratories at determined time
intervals (Table Ι) or by the OPERATOR personnel in accordance with the calibration
procedures (Article 35, Table ΙΙ). Such instruments make up either the NGTS Station
supporting metering equipment such as pressure, differential pressure, temperature
transmitters or main metering equipment such as the various meter types (Table IV). Also
Custody Transfer Instruments include Gas chromatographs, and Dew Point
Analyzers.
Article 25. Main Metering Instrument Groups
With regard to the various groups in which metering instruments can be included, these are established by
the various variables involved in the specific measurement procedures. In general the main variables for
the Natural Gas Transmission System are:
 Temperature
 Pressure
 Gas Flow
Therefore, the most important instrument groups with regard to the above variables can be summarized as
follows:
 Thermometers (Analog or Digital/ Transmitters)
 Manometers (Analog or Digital/ Transmitters)
 Flow Meters (Turbine, Rotary Positive Displacement, etc. meters)
Article 26. Temperature - Thermometers
26.1 Temperature Measurement Principles
The magnitude or the quantitative value of temperature may not be determined directly.
Therefore, the temperature value is determined indirectly and on the basis of certain matter
characteristics, which change as a function of temperature increases or drops. Such
characteristic properties are:
 Length or Volume (based on thermic expansion)
 Electric changes (changes to elecrtric resistance)
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 Visual properties
The following are widely used in the Natural Gas Transmission System either in the laboratory
or in the measurement processes:
26.2 Thermic Expansion Thermometers - Mercury Piliform or Glass Tube
Thermometers
Temperature increases lead to changes in the volume of solids, fluids and gases, namely the
above forms of matter expand as a function of temperature increase. This is basically the main
property on which the operation of plain mercury or other fluid thermometers is based (fluids
expand as the temperature increases).
26.3 RTD-Resistant Temperature Detectors
RTD-Resistant Temperature Detector operate with a measurable change in the resistance of
the metal or thermistor as a function of temperature. The metal used is platinum, copper or
nickel and the thermistor is a metal oxide.
RTD electrical resistance changes as a function of temperature. An electric circuit similar to
that of a Wheatstone bridge is installed in control systems designed to be used with RTDs. A
continuous current in the bridge generates an Exit voltage which changes as a function of
temperature.
26.4 Temperature Transmitters
Temperature Transmitters are used to transmit temperature to remote points from the physical
point where the measurement is taken. The transmission or connection point transmits the
temperature of the medium to a remote point and may be the system control center or units and
the data processing and control systems for the measurement process.
The main operation principle of a temperature transmitter is to convert the temperature value
to an electric signal from 4 mA to 20 mA, and transmit this to the final receiver, which
receives such electric signal and converts it to temperature reading. The transmitter is
calibrated using the above scale.
Article 27. Pressure – Pressure Gauges
The transmission system uses various pressure gauges, mechanical or digital. With regard to mechanical
pressure gauging, the main principle of operation is that the existence of the static pressure of a fluid or
gas medium causes the mechanical change of an accessory or part of the metering instrument. This
change is converted to a measurement on a calibrated pressure scale using a mechanical indicator. With
regard to the digital recording of the measurement reading, this is done by gauges that convert the
primary value through an electronic process to an indication on a screen. Such instruments can be
designed with increased precision, always depending on the application for which they are intended.
27.1 Pressure Transmitters
The main operation principle of a pressure transmitter is to convert the measurable pressure
value to an electric signal from 4 mA to 20 mA, and transmit this to the final receiver, which
receives such electric signal and converts it to pressure reading. The transmitter is calibrated
using the above scale. Such instruments can be recalibrated using special devices (HART
Communicator) for increased precision in readings and transmission.
The pressure transmitter used to measure and transmit the absolute gas pressure to the NGTS
Metering and Regulation Station uses a piezoresistive silicon sensor, which provides an
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increased level of precision and operation for absolute pressure measurements. The digital
technology employed ensures high precision for the reading range, as well as communication
of the measurement point (field) with the central data control processing area.
The sensor comprises a “Wheatstone bridge” electric circuit which has been created using
silicon resistances on a silicon layer. The process pressure is transmitted using the isolated and
filled with fluid orifice to the sensor element, leading to a very small displacement of the
silicon layer. The resulting microforce (small mechanical tension) that is applied to the layer
changes the electrical resistance of the Wheatstone bridge depending on the pressure applied.
In this way a mechanical tension changes to an analog magnitude electrical conversion and a 4
- 20 mA signaling is transmitted to provide the measurable magnitude of the change to the
final recipients of the measurement with reliability and increased precision.
Article 28. Flow Meters
28.1 Turbine Meters
Turbine meters are inductive meters widely used in the natural gas metering system. Its
principle of operation is the following:
The gas enters the turbine meter through a flow normalizer, which imposes a smooth gas flow,
then passes through a ring channel and causes the turbine to move. The gas current
compression that takes place inside the ring channel increases the speed of the gas so as to
provide higher rotation torque to the turbine. The turbine comprises a wheel with flaps
arranged on it at an angle between 30 and 45°. The gas current causes the turbine to revolve at
a speed proportional to the speed of the gas. The overall gas volume that goes through the
meter during the time unit (supply) is equal to the speed of the gas multiplied by the ring
channel surface area, and each revolution of the turbine corresponds to a specific gas volume
passing through the meter. Depending on the Qmin/Qmax ratio, such meters fall under three
categories:
 Short range, Qmin/Qmax = 1/5
 Medium range, Qmin/Qmax = 1 / 1 0
 Large range, Qmin/Qmax = 1 / 2 0
Start supply is Qmax/100.
Allowable measurement errors for turbine meters are:
 For Qmin < Q < 0.2Qmax, 2%
 For 0.2Qmax < Q < Qmax, 1%
More detailed reference is made to this meter in standards EN 12261 and ISO 9951 (Table V).
28.2 Rotary Meters
Rotary meters are volumetric meters used to measure gas mainly at commercial and industrial
customers. They are also called rotary positive displacement meters or rotary piston gas
meters. A rotary meter comprises two pistons that rotate in opposite direction inside a fixed
measurement chamber.
The measurement chamber and the gas exit are placed the one across from the other. The
pistons are made so as to allow constant water tightness without the pistons touching at any
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position. The combined movement of the pistons is attained through two gears placed on the
piston shafts.
During the full rotation of the pistons around their axis, a gas quantity equal to four times the
volume included between the piston in horizontal position and the measurement chamber
passes through the meter.
Depending on the Qmin/Qmax ratio, such meters fall under three categories:
 Short range, Qmin/Qmax = 1/5
 Medium range, Qmin/Qmax = 1 / 1 0
 Large range, Qmin/Qmax = 1 / 2 0
The starting supply ranges between Qmax/800 and Qmax/300.
Allowable measurement errors for rotary meters are:
 For Qmin < Q < 0.2Qmax, 2%
 For 0.2Qmax < Q < Qmax, 1%
More detailed reference is made to this meter in standard EN 12480 (Table V).
28.3 Ultrasonic Flow Meters
Ultrasonic flow meters are metering devices which comprise ultrasonic transceivers placed
inside the metering device conductors. The principle of their operation is based on ultrasonic
pulses transmitted by a transmitter and received by a receiver at an angle φ (Doppler
phenomenon).
Without flow, a pulse from transceiver Α to transceiver Β shall travel at the same speed
compared to the speed of a pulse from B to A (the speed depends on the transmission
medium).
If inside the conductor there is gas moving at a speed other than zero, then the pulse from A to
B shall travel at a speed (greater or less depending on the direction of the gas) other than that
from B to A.
The two pulse transmission times are measured electronically, determining in this way the gas
movement speed. Using the gas movement speed the flow can be calculated under operating
and reference conditions.
Usually, multiple path devices with reflectors are used.
The usual measurement errors are:
 For Qmin < Q < 0.05Qmax, 1 %
 For 0.05Qmax < Q < Qmax,
0,05%
More detailed reference is made to this meter in standard ISO AGA 9 (Table V).
28.4 Orifice Meters
At restriction type - orifice meters the pressure drops when the flow conductor diameter
changes and the fluid speed increases. By establishing the pressure drop, the volumetric flow
is determined. The fluid flow rate is proportional to the square root of the pressure drop.
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More detailed reference is made to this meter in standard ISO 5167 (Table V).
28.5 Coriolis Mass Flow Meters
Coriolis meters operate based on the principle that inertia forces are generated whenever a
molecule inside a rotating body moves in respect of such body towards or away from the
rotation center.
Therefore, the (direct or indirect) measurement of the Coriolis Force that the flowing fluid
applies on a rotating tube can provide a measurement of the mass flow rate.
More detailed reference is made to this meter in standard ISO 10790 (Table V).
Article 29. Gas Chromatographs
The main characteristics of a gas chromatograph is the sample introduction chamber, the chromatographic
column and the detector. The carrier gas is included in metal bottles and provided to the device using one
or more pressure regulators. The carrier gas transfers the sample ingredients inside the column where they
are separated from one another and go through the detector, which sends a signal to a recorder. The
column, the sample introduction system and the detector are found in fixed temperature heated chamber.
More detailed reference to the carrier gas, the sample introduction, the chromatographic columns, the
filling material, the detectors, the qualitative and quantitative analysis and the normalization of results is
made in standard ISO 6974 (Table V).
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METERING PROCEDURES
Article 30. NGTS Metering Station Equipment
The NGTS metering station equipment comprises the main equipment for flow and energy volumetric
measurement and the supporting equipment for measuring static pressure, differential pressure and
temperature in the meter run.
The NGTS metering station equipment falls under three categories:
1.
turbine meters, rotary positive displacement meters, ultrasonic flow meters and supporting
equipment: pressure, temperature transmitters or built-in pressure and temperature sensors in PTZ
correctors
2.
orifice meters and supporting equipment: static pressure, differential pressure, temperature
transmitters, and densimeters.
3.
mass meters without supporting equipment.
In all three types of metering equipment Gross Calorific Value per gas volume unit and relevant density
are calculated as a function of the gas composition which is obtained from a gas chromatograph.
NGTS metering station equipment is described in the Tables attached to Appendix 2 for each NGTS
station, including the respective possible overall errors of individual supporting instruments and the
overall energy uncertainty. More details about the precision of instruments and the equipment in general
are given in Article 6 on Uncertainty Studies.
Article 31. Measurement Procedures
The actions, reports and the necessary management of measurements at each Entry or Exit point shall be
the subject matter of Measurement Procedures.
More specifically:
The User may deliver NG to the Operator for transmission through the NGTS at the following Entry
Points:

At the Border Metering Station (BMS) at Sidirokastro, Serres which is interconnected upstream
with the System of Bulgaria.

At the Aghia Triada Metering Station which is interconnected with the NGTS LNG gasification
facility.

At the Kipi Metering Station that is interconnected upstream to the Transmission System of
Turkey (future)
Quality specifications and the delivery and offtake conditions for each Entry and Exit point are
established in Annex E.
A description of the Metering Stations and the design and operation specifications are given in Appendix
2.
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Article 32. Exit Points
The NGTS Exit Points are classified as "Type A Exit Points" and "Type B Exit Points" as is shown in
Table VI (Table VIΙ lists future stations). This classification refers exclusively to the time period during
which the User may be informed about the measurements taken.
Until 13:00 hours each Day, the Operator shall collect the information on the Natural Gas Quantity
delivered by the Operator and offtook by the users at the Metering Station Exit Point during the previous
Day. Such information is indicative and aim at informing the Parties with regard to the Allocation.
Each business Day every user may be informed by fax or e-mail about the indicative NG quantity
delivered to them by the Operator on the previous Contractual Day at the given Metering Station,
provided such Station is part of a user nominated Exit Point.
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CALIBRATION
Article 33. Equipment Calibration
Table ΙΙΙ lists the Metering Equipment calibration equipment along with precision of each respective
instrument. The precision of a standard instrument must be at least three times better than the respective
precision of the metering instrument to be calibrated.
Depending on the measured magnitudes to be calibrated, the calibration equipment is classified as static
pressure, differential pressure, temperature, etc. calibration equipment.
Below are given the principal standard instruments (working devices) for static pressure, differential
pressure, and temperature that are used in general and more specifically to calibrate the Operator's
metering station equipment.
33.1 Static Pressure - Deadweight tester
The main tester for pressure is the Deadweight tester.
The principle of operation of a device used to generate a calibrated reference pressure is: a
piston with an accurately known base surface area is placed inside a cylinder. Next, known
standard masses are placed on the piston. A pump supplies oil at sufficient pressure to lift the
standard masses. The force applied by the oil pressure on the surface of the piston is balanced
by the weight of the standard masses.
33.2 Differential Pressure - Double Piston Standard Mass Tester
Double piston standard mass testers are used to calibrate differential pressure transmitters at
their static pressure operation. The device mainly applies a common static pressure on the low
and high pressure extremes of the differential pressure transmitter. Next, the low pressure
extreme is isolated, and the high pressure extreme is successively calibrated at the desirable
differential pressure range.
33.3
Static Pressure - Gas Pressure Controller (GPC) Standard Pressure
The GPC is an automatic pneumatic pressure tester and calibrator.
The pressure is measured by a triple range quartz sensor with an precision of +/- 0.005% for
each measurement range.
33.4 Standard High Precision (PHP 602) type Thermometer
The PHP 602 is a highly accurate standard temperature measuring device. It is connected to
and operates through a computer. A suitable software processes the measurements, calibrates
the temperature sensors and issues a relevant report.
Its main applications are:
• temperature measurements using RTD sensors;
• bath temperature stability check.
33.5 Hart communicator
NATURAL GAS TRANSMISSION CONTRACT - APPENDIX C2
Page 30 / 80
Unofficial translation
The communication setting and level of the (static, differential) pressure or temperature
transmitter are attained using a communication device which is called HART Communicator
(Highway Addressable Remote Transducer).
Such device is not a metering device and requires no calibration. It is an electronic
communication device through which it is possible to notify and set the pressure and
temperature transmitter operation elements. All Exit variables this device sows are elements
of the transmitter to which the communicator has been connected.
The most important operational parameters of the communicator and the measurement in
general that may be displayed and managed include:
1.
Real Entry magnitude (process variable - pressure / temperature)
2.
Real analog exit (4 - 20 mA)
3.
Metering Instrument Low Range Value
4.
Metering Instrument High Range Value
Article 34. Metering Equipment Calibration Frequency
The Metering Equipment undergoes Precision Testing at regular intervals.
Table ΙΙ indicates the Metering Equipment Calibration Procedures as compared to the individual
equipment.
A Calibration Procedure includes both Metering Equipment Precision Testing and Regulation against the
standard reference equipment (working device) used by the Operator, called Calibration Equipment and is
indicated in Table ΙΙΙ.
Users shall be invited to and entitled to attend Metering Equipment calibration by the Operator.
Calibration results are entered in relevant forms.
The frequency with which calibration is performed by the Operator’s personnel is established in the
Operator’s ANNUAL CALIBRATION SCHEDULE which is notified to Users in a timely manner (each
December of the previous year).
The provisions of Article 4 of this Measurement Regulation are implemented in installing each element of
the metering equipment at a NGTS Entry or Exit point.
The frequency of metering equipment recalibration at special metrological laboratories in Greece or
abroad is in accordance with Table Ι and the relevant Calibration Certificate is issued.
Article 35. Metering Equipment Calibration Procedures
These procedures concern the periodic calibration of and the checks on the NGTS Metering Equipment
and individual instruments (70/19 bar) (Table ΙΙ)
The objective of the procedures is to attain a uniform calibration and checking method at all Entry/ Exit
Points resulting in the safe and reliable operation of the NGTS Metering Equipment.
35.1
Calibration of Two Turbine Meter Runs and Flow calculator Checking
This procedure includes:

Pressure and Temperature transmitter calibration using the respective Working Standards
(Table ΙΙΙ)
NATURAL GAS TRANSMISSION CONTRACT - APPENDIX C2
Page 31 / 80
Unofficial translation

35.2
Flow calculator checking using a pulse generator (Table ΙΙΙ), checking the programmed
parameters and the correction coefficient calculation employing a standard software
In Line Turbine Meter Checking
This procedure includes:
35.3

turbine meter checking by connecting two meter runs in line for a given time period and
given volume and pressure flow conditions

checking of programmed parameters that regard the calibration characteristics of
turbine meters in flow calculators
Calibration of two Ultrasonic Flow Meter Runs
This procedure includes:
35.4

pressure and temperature transmitter calibration using the respective Working Standards
(Table ΙΙΙ)

checking of the programmed parameters and the correction coefficient calculation at the
flow calculators using a standard software
Orifice Meter Run Calibration
This procedure includes:

pressure, differential pressure and temperature transmitter calibration using the respective
Working Standards (Table ΙΙΙ)

checking of the programmed parameters and the correction coefficient, volume and
energy flow calculation at the flow calculator using a standard software (Table III)
Note: the above procedure may also include a densimeter check
35.5
Orifice Meter Checking
This procedure includes:
35.6

visual checking of the orifice meter in accordance with ISO 5167 (Table V) and checking
its internal diameter using a Micrometer (Table ΙΙΙ)

checking the programmed calibration parameters of the orifice meter at the flow
calculator
Gas Chromatograph Calibration
This procedure includes:
35.7

checking the response coefficients that result from successive analyses of the standard
gas based on ISO 6974 (Table V)

checking the composition values that result from successive standard gas analyses
(Table ΙΙΙ)

checking the natural gas Gross Calorific Value calculation from the chromatograph in
accordance with ISO 6976 (Table V) the certified composition of the standard gas at the
chromatograph
Dew Point Analyzer Checking
NATURAL GAS TRANSMISSION CONTRACT - APPENDIX C2
Page 32 / 80
Unofficial translation
This procedure concerns checking the dew point Analyzer by using a device based on the
chilled mirror principle (Chandler Dew Point Tester-Table ΙΙΙ).
NATURAL GAS TRANSMISSION CONTRACT - APPENDIX C2
Page 33 / 80
Unofficial translation
TABLES
ΠΙΝΑΚΑΣ Ι. Έλεγχος Μετρητικού ΕξοπλισμούTABLE Ι. Metering
Equipment Checking
No.
METERING
INSTRUMENTS
(METERS)
CHECK FREQUENCY
CHECK CERTIFICATE
1
TURBINE
5 years or when considered necessary
following a periodic check
Certified Laboratory or national
metrological institute Certificate
2
ULTRASONIC FLOW
5 years or when considered necessary
following a periodic check
Certified Laboratory or national
metrological institute Certificate
3
ORIFICE
When considered necessary after a
check performed at least once a year
4
MASS
Every 2 years
5
ROTARY POSITIVE
DISPLACEMENT
8 years or when considered necessary
following a periodic check
Check by a specialized
laboratory or the manufacturer
Check by a specialized
laboratory or the manufacturer
Certified Laboratory or national
metrological institute Certificate
ΠΙΝΑΚΑΣ ΙΙ.TABLE ΙΙ. Διαδικασίες Βαθμονόμησης του Εξοπλισμού
ΜέτρησηςMetering equipment calibration procedures
No.
PROCEDURES
1
Calibration of Two Turbine Meter Runs and Flow
calculator Checking
ΕΠΙΜΕΡΟΥΣ ΟΡΓΑΝΑ ΜΕΤΡΗΣΕΩΝ ΑΝΑΛΥΣΗΣ INDIVIDUAL METERING ANALYSIS INSTRUMENTS
Temperature Transmitters, Pressure Transmitters, Flow
Calculators
2
In Line Turbine Meter Checking
Turbine Meters, Flow Calculators
3
Calibration of two Ultrasonic Flow Meter Runs
4
Orifice Meter Run Calibration
5
Orifice Meter Checking
Orifice Meters, Flow Calculators
6
Water Dew Point Analyzer Checking
Water dew point analyzer
7
Carbohydrate Dew Point Analyzer Checking
Carbohydrate dew point analyzer
8
Gas Chromatograph Calibration
Gas chromatograph
NATURAL GAS TRANSMISSION CONTRACT - APPENDIX C2
Temperature Transmitters, Pressure Transmitters, Flow
Calculators
Temperature Transmitters, Pressure Transmitters,
Differential Pressure Transmitters, Densimeters, Flow
Calculators
Page 34 / 80
Unofficial translation
TABLE ΙΙI. Calibration Equipment Standards
2
3
4
5
6
7
8
9
10
11
12
TEMPERATURE
1
Magnitudes to
be Calibrated
STATIC
PRESSURE
DIFFERENTIAL
PRESSURE
No.
VOLUME
FLOW
WATER DEW
POINT
GROSS
CALORIFIC
VALUE GAS
COMPOSITION
DIAMETER
Working Devices (Standards)
Precision
(Indicative)
Use
Deadweight Ball Manometer
±0.015%
Differential Pressure Generation
Double Piston Deadweight Manometer (nominal
conversion coefficient 0.5 Mpa/Kg)
±0.015%
Differential and Static Pressure Generation
Gas pressure controller
±0.005%
Static Pressure Generation - Indication
Barometer
±0.10%
Barometric Pressure Indication
High Precision Thermometer (digital)
±0.014%+
0.014oC
Temperature Indication (portable instrument)
Mercury Thermometer
±0.1 oC
Temperature indication
Temperature Bath
±0.1 oC
Hart Communicator
-
Temperature Generation using high precision
Thermometer for Temperature Indication
Digital Communication with Static Pressure, Differential
Pressure, Temperature transmitters
Pulse generator
Pulse Generation for Flow Calculator Control
Chandler
±2 oC
Water dew point determination
Standard gas
±0.1%
Standard gas mixture for Gas Chromatograph Calibration
Micrometer
<±2 μm
Orifice Meter Diameter Measurement
Note: this table is not exhaustive, but serves the purpose of illustrating the working standards used by the Operator for calibration. It may be revised
annually.
NATURAL GAS TRANSMISSION CONTRACT - APPENDIX C2
Page 35 / 80
Unofficial translation
TABLE IV. Custody Transfer Instruments - (Measurement) Precision Standards - Procedures, Methods
PRICING
INSTRUMENTS
PRECISION (Indicative)
(MEASUREMENT)
PRECISION
STANDARDS
MEASURED MAGNITUDES
(UNITS)
Coriolis Meters
±0.7%
ISO 10790
MASS
(Kg)
Turbine Meters
±0.37%
Ultrasonic flow meters
± 0.7%
Orifice meters
±0.5% (outflow coefficient)
ISO 5167
Rotary Positive
Displacement Meters
with lobes
±0.5%
EN 12480
ANSI B109.3
Densimeters
±0.2%
ISO 6976-AGA 8
Pressure Transmitters
±0.15%
Differential pressure
transmitter
Temperature
Transmitters
Gas chromatographs
±0.15%
±0.14%
±0.2% (Gross Calorific
Value)
ISO 9951
EN 12261
AGA 9
ISO 9951
EA 10/17, EN 837-1, EN
837-2, EN 837-3
EA 10/17, EN 837-1, EN
837-2, EN 837-4
EA 10/11
ISO 6568
ISO 6974
ISO 6976
Oxygen Analyzers Gas Chromatographs
±50%
Gas chromatographs
±0.2% (Gross Calorific
Value)
ISO 19739
±2
ASTM/D 1142
±1
ASTM/D 1142
-
ISO 10715
Water dew point
analyzers
Carbohydrate dew
point analyzers
-
NATURAL GAS TRANSMISSION CONTRACT - APPENDIX C2
CALCULATED MAGNITUDES
(UNITS)
METHODS
UNCORRECTED VOLUME
(m3)
CORRECTED VOLUME
(Nm3)
DENSITY
(Kg/m3)
PRESSURE
(bar)
DIFFERENTIAL PRESSURE
(mbar)
TEMPERATURE
(oC )
GAS CONTENT IN
CXHY,C02,N2
(%mole)
MEASUREMENT
GROSS CALORIFIC VALUE
(MJ/Nm3)
OXYGEN
(%mole)
RSH,H2S
(mg/m3)
H2O DEW POINT
o
C (at 38,2 bar)
H/C DEW POINT
o
C (at line pres. [bar])
Page 36 / 80
GAS QUALITATIVE &
QUANTITATIVE ANALYSIS
ANALYSIS
-
SAMPLING
Unofficial translation
Note: the standards refer to versions that are in force and may be revised or supplemented by the International Organizations issuing them.
NATURAL GAS TRANSMISSION CONTRACT - APPENDIX C2
Page 37 / 80
Unofficial translation
NATURAL GAS TRANSMISSION CONTRACT - APPENDIX C2
Page 38 / 80
Unofficial translation
Gas Volume - Mass - Energy Measurement
ΠΙΝΑΚΑΣ V. Ισχύοντα Πρότυπα Κανονισμού Μετρήσεων ΕΣΜΦΑTABLE V.
NGTS Measurement Regulation Applicable Standards
ISO 9951
: Measurement of Gas flow in closed conduits – Turbine meters
EN 12261
: Gas Meters-Turbine gas meters
EN 12480
: Gas Meters-Rotary displacements gas meters
ISO 5167
: Measurement of fluid flow by means of pressure differential devices inserted in
circular - cross section conduits running full – Orifice plates
ISO 5168
: Measurement of fluid flow – Evaluation of uncertainties
ISO 6976
: Natural gas – Calculation of calorific values, density, relative density and
Wobbe index from composition
ISO 10790
: Measurement of Gas flow in closed conduits – Guidelines to the selection,
installation and use of Coriolis meters (mass flow, density, and volume flow
measurements)
ISO 12213
: Natural gas – Calculation of Compression Factor
AGA 3
: Orifice Metering of Natural Gas
AGA 7
: Measurement of Gas by Turbine Meters
AGA 8
: Compressibility Factor of Natural Gas and Related Hydrocarbon Gases
AGA 9
: Measurement of Gas by Multipath Ultrasonic Meters
AGA 11
: Measurement of Gas by Coriolis Meter
ANSI
B109.3
: Rotary -Type Gas Displacement meters
Sampling
Gas quality/ analysis
GUM
Guide Uncertainty of Measurement
EN 1776
: Gas supply – Natural gas measuring stations – Functional requirements
ISO 6974
: Determination of cοmposition with defined uncertainty by gas chromatography
ISO 14111
: Natural gas – Guidelines to traceability in analysis
ISO 19739
: Natural gas – Determination of sulfur compounds using gas chromatography
ISO 6326
: Natural gas – Determination of sulfur compounds
ISO 6142
: Gas analysis – Preparation of calibration gas mixtures – Gravimetric method
ISO 6143
: Gas analysis – Comparison methods for determining and checking the
calibration gas mixtures’ composition
ISO 6327
: Gas analysis – Determination of the water dew point of natural gas – Cooled
surface condensation hygrometers
ISO 10715
: Natural gas – Sampling guidelines
NATURAL GAS TRANSMISSION CONTRACT - APPENDIX C2
Page 39 / 80
Unofficial translation
Note: the standards refer to versions that are in force and may be revised or supplemented by the
International Organizations issuing them.
NATURAL GAS TRANSMISSION CONTRACT - APPENDIX C2
Page 40 / 80
Unofficial translation
Μ/R LAMIA
Β*
TABLE VI NGTS Exit Points
TABLE VIΙ Future NGTS Stations
EXIT POINT
STATIONS
TYPE *
No.
1
2
3
4
5
6
7
8
9
10
STATION
Μ - ΜΟΤOR OIL
M/R SERRES ***
M/R DRAMA
M/R KOSMIO
M/R XANTHI ***
M/R KILKIS
M/R ENERGIAKI THESSALONIKIS
Μ/R KATERINI
M/R LAMIA
M/R THIVA
KERATSINI
M KERATSINI
Α
LAVRIO
M LAVRIO
Α
KOMOTINI
Μ/R KOMOTINI
Α
VFL
M VFL
Α
Μ/R EASTERN THESSALONIKI
Α
Μ/R NORTHERN THESSALONIKI
Α
PLATI
Μ/R PLATI
Α
ELPE
M/R EKO
Α
SALFA Ι
Α
SALFA ΙΙ
Β
M/R EASTERN ATHENS
Α
M/R NORTHERN ATHENS
Α
** Metering station to be constructed. For the time being measurements are taken
M/R WESTERN ATHENS
Α
at a metering station not owned by the Operator
M/R THRIASIO
Α
M/R ASPROPIRGOS
Α
M/R MARKOPOULO - TM2
Α
IRONAS
M IRONAS
Β
ENERGIAKI THESSALONIKIS
M/R ENERGIAKI THESSALONIKIS
**
Β
M/R KOMOTINI
Α
Μ/R KAVALA
Α
M/R XANTHI
Α
M/R SERRES
Α
Μ/R NORTHERN LARISSA
Α
Μ/R SOUTHERN LARISSA
Α
Μ/R LARISSA INDUSTRIAL AREA
Β
Μ/R KOKKINA
Α
Μ/R VOLOS
Α
Μ/R INOFITA
Α
THESSALONIKI
SALFA
ATTICA
EASTERN MACEDONIA THRACE
CENTRAL MACEDONIA
THESSALY
STEREA ELLADA - EVIA
NATURAL GAS TRANSMISSION CONTRACT - APPENDIX C2
* The separation of Stations into Type A/ B is referred to in Article 32
*** These stations operate as temporary stations (Appendix 2) with future
specifications regarding the construction of new stations
Page 41 / 80
Unofficial translation
FORMS
Form 1. Daily NG Quantity and Measurement Characteristics Report at a Metering Station Entry Point
Form 2. Daily NG Quality Composition Report at a Metering Station Entry Point
Form 3. Monthly NG Quantity and Measurement Characteristics Report at a Metering Station Exit Point
Form 4. Monthly NG Qualitative Composition Report at a Metering Station Exit Point
Form 5. Erroneous Quantities Protocol
NATURAL GAS TRANSMISSION CONTRACT - APPENDIX C2
Page 42 / 80
Unofficial translation
DAILY NG QUANTITY AND MEASUREMENT
CHARACTERISTICS PROTOCOL AT ENTRY POINT
Entry point: ……………………………………………………….
Written on: ……………………………………………………….
Reference Date: ……………………………………………………….
TOTAL QUANTITY
Volume VΝ =……………………………..
Energy =……………………………..
Nm3
ΜJ
MEASUREMENT CHARACTERISTICS AVERAGE VALUE
GCV =……………………………..
PENTRY =……………………………..
ΤEXIT =……………………………..
rd =……………………………..
MJ/Nm3
Barg or Bara
oC
-
Wobbe Index =……………………………..
MJ/Nm3
H2S =……………………………..
mg/Nm3
Total Sulfur =……………………………..
mg/Nm3
H2Ο Dew Point =……………………………..
oC
(in P=……….........barg)
HC Dew Point =……………………………..
oC
(in P=……….........barg)
REMARKS
1. Water and carbohydrate dew points refer to a pressure ≤ 80 barg
2.
The values are weighted averages (values per hour) with the exception of the H 2O and
HC dew points which are the average of at least three (3) measurements
3.
Energy measurements in MJ refer to GCV and to a temperature of 0 oC
4.
Quantity measurements in Nm 3 refer to 0 oC and 1.01325 bara conditions
THE OPERATOR
THE USERS
…………………
…………………
NATURAL GAS TRANSMISSION CONTRACT - APPENDIX C2
Page 43 / 80
Unofficial translation
DAILY NG QUALITY COMPOSITION PROTOCOL AT
ENTRY POINT
Entry point: ……………………………………………………….
Written on: ……………………………………………………….
Reference Date: ……………………………………………………….
TOTAL QUANTITY
C1 =……………………………..
%mole
C2 =……………………………..
%mole
C3 =……………………………..
%mole
i-C4 =……………………………..
%mole
n-C4 =……………………………..
%mole
i-C5 =……………………………..
%mole
n-C5 =……………………………..
%mole
C6+ =……………………………..
%mole
CO2 =……………………………..
%mole
N2 =……………………………..
%mole
O2 =……………………………..
%mole
THE OPERATOR
THE USERS
…………………
…………………
NATURAL GAS TRANSMISSION CONTRACT - APPENDIX C2
Page 44 / 80
Unofficial trasnlation
MONTHLY NG QUANTITY AND MEASUREMENT CHARACTERISTICS PROTOCOL
AT EXIT POINT
DAILY QUANTITY REPORT
Gas month :
printout mode :
Page :
Per contract month
DELIVERY POINT:
Contract Day
……………………………………………
Meter Run …
Vb-c (m³)
Vn(Nm³)
E (MJ)
P (bara)
T (°C)
Sum of Meters Runs
Vb-c (m³)
Vn(Nm³)
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
NATURAL GAS TRANSMISSION CONTRACT - APPENDIX C2
Page 45 / 80
1 of 2
E (MJ)
E(Gcal)
Unofficial translation
Totals
NATURAL GAS TRANSMISSION CONTRACT - APPENDIX C2
Page 46 / 80
Unofficial translation
MONTHLY NG QUALITY COMPOSITION PROTOCOL AT EXIT POINT
DAILY QUALITY REPORT
Per contract month
DELIVERY POINT:
Contract Day
C1
(mol%)
……………………………………………….
C2
(mol%)
C3
(mol%)
i-C4
(mol%)
n-C4
(mol%)
i-C5
(mol%)
n-C5
(mol%)
neo-C5
(mol%)
C6+
(mol%)
N2
(mol%)
CO2
(mol%)
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
NATURAL GAS TRANSMISSION CONTRACT - APPENDIX C2
Page 47 / 80
O2
(mol%)
Gas month :
printout mode :
Page :
hs dry
rd
(MJ/Nm³)
2 of 2
Zn
Wobbe
Unofficial translation
31
Averages
NATURAL GAS TRANSMISSION CONTRACT - APPENDIX C2
Page 48 / 80
Unofficial translation
MONTHLY NG ERRONEOUS QUANTITIES PROTOCOL AT ENTRY OR
EXIT POINT
Point:……………………………………………………….
Written on:……………………………………………………….
Reference Date:……………………………………………………….
Day
VΝ
Nm3
Station Total
GCV
MJ/Nm3
E
ΜWh
Comments
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
Total
THE OPERATOR
……………………………
NATURAL GAS TRANSMISSION CONTRACT - APPENDIX C2
THE USERS
……………………………
Page 49 / 80
Unofficial translation
APPENDIX 2
STATION DESCRIPTION - TECHNICAL SPECIFICATIONS
ENTRY POINTS
Next follows the general description of the design - operation of the Metering Stations at all Entry
Points.
General description of the design - operation of the M Aghia Triada Metering Station
This station comprises two metering runs the characteristics of which are given in a table below.
During normal station operation only meter run No 1 (main meter run) operates, while meter run No. 2
(backup meter run) is in standby.
To ensure the smooth operation of the equipment and the uninterrupted supply of the NGTS, meter run
No 2 is turned on in parallel with meter run No 1 where flow requirements exceed the upper flow limit of
current meter No 1. In this case the flow is automatically divided between the two meter runs. Such
operation takes place where normal operating conditions of the Aghia Triad Metering Station are
violated.
Meter run No 2 is also manually turned on, independently of meter run No 1, during maintenance work
on meter run No 1.
Quality parameters are constantly monitored using gas chromatographs in line with the system. Gas
composition is then transferred to the Measurement Management System - MMS (supervising
computers), which use it, along with the pressure and temperature readings from the pressure and
temperature transmitters, to calculate current gas compressibility. At the same time, the above are also
forwarded to the flow calculators, which use such information to convert the pulses they receive from the
flow meters to energy, mass, and volume flow rates.
Under normal operating conditions (full functionality) the station operates without the presence of
personnel, as it is monitored by the OPERATOR’s SCADA system. However, all necessary measures are
adopted to ensure that the station can be operated through the station control panel by OPERATOR
personnel where (for technical reasons) the supervision and teleoperation of the station is not possible
from the control center or under emergency conditions or when the OPERATOR finds this solution as the
most suitable one in terms of operation.
General description of the design - operation of the Sidirokastro Border Metering Station
The Border Metering Station in Sidirokastro, Serres near the border of Greece with Bulgaria measures
and regulates the flow of imported natural gas. The Station equipment includes filters, meters,
chromatographs and other analyzers, heat alternators and boilers, regulation valves, as well as control
systems for the operation of such facilities. Flow is measured at four parallel meter runs with a diameter
of 16΄΄ using an orifice meter.
The main design specifications are listed below in a table.
NATURAL GAS TRANSMISSION CONTRACT - APPENDIX C2
Page 50 / 80
Unofficial translation
General description of the design - operation of the Kipi Metering Station (to be issued - Future
Metering Station)
Provision is made for three meter runs in conjunction with the turbine meter and the ultrasonic flow
meter in line for each meter run and the use of primary and backup chromatographs, as well as
Measurement Management System (MMS).
EXIT POINTS
Next follows the general description of the design - operation of the Metering (M) or Metering/
Regulation (M/R) Stations at all Exit Points.
General description of the design - operation of orifice meter stations with ultrasonic flow meter
for startup (Lavrio M Station and Komotini M/R Station)
The installed station comprises one part with parallel filters-separators with a condensate collector, a part
with parallel runs (three at M/R KOMOTINI and four at M-LAVRIO) each of them fully equipped with
an orifice meter, a "startup” system with dual ultrasonic meters, a gas exit isolation valve and the
necessary branching valve which allows or not gas from passing when the startup part is on or off
respectively, as well as intermediate and external collectors.
At M/R Komotini following the metering device there is a regulation device in line which comprises two
regulation lines with one heat alternator on each one. There is also a container with three boilers as well
as two gas entry metering-regulation lines to supply the boilers.
The main design specifications are listed below in a table.
Natural gas quality parameters such as calorific value, composition and water and carbohydrate dew point
are constantly recorded by two gas chromatographs, one oxygen analyzer, a water dew point analyzer and
one carbohydrate dew point analyzer.
The constantly recorded natural gas composition and its quality parameters are forwarded to the
supervising computers and used together with other digital data coming from temperature and pressure
transmitters to calculate compressibility.
The foregoing gas composition is also forwarded to measure flow, and it is used together with other
digital data coming from temperature, pressure, and differential pressure transmitters from the respective
flow calculators (orifice meters or ultrasonic meter) to calculate flow and energy.
All station operations are monitored and checked by a central control station using a computer (main and
backup) system and programmable logical controllers (main and backup), so that the presence of
personnel at the station is not necessary under normal conditions. However, provision is made for all
necessary equipment are adopted to ensure that the station can be operated through the station control
panel or locally by OPERATOR personnel where (for technical reasons) the supervision and teleoperation
of the station is not possible using the SCADA system or under emergency conditions or when the
OPERATOR finds this solution as the most suitable one in terms of operation.
NATURAL GAS TRANSMISSION CONTRACT - APPENDIX C2
Page 51 / 80
Unofficial translation
General description of the design - operation of the Ultrasonic Meter Station (M-Ironas)
An installation of dual ultrasonic meters, the respective flow calculators and the Measurement
Management System (MMS). Provision is made for the installation of a chromatograph and a third
backup meter run (also with an ultrasonic meter - flow calculator), connection with the SCADA system.
The chemical composition for calculating the GCV and the Energy is obtained by the OPERATOR using
information obtained from a gas chromatograph at a neighboring entry or exit point.
General description of the design - operation of Stations with a turbine meter, flow calculator,
MMS and chromatograph (e.g. M-Keratsini, M-VFL, City Exit Points)
The description of such stations is similar to that of the Aghia Triada Metering Station, noting that the
City Exit points also have a pressure regulator on each meter run.
General description of the design - operation of Stations with a turbine meter, flow calculator,
chromatograph and without MMS (e.g. M-EKO)
The description of such stations is similar to that of the Aghia Triada Metering Station, noting that there
is no Measurement Management System (MMS) and that there may be a pressure regulator on each
meter run.
General description of the design - operation of Stations with turbine meter and/ or rotary positive
displacement meter, with PTZ corrector without MMS and chromatographs (e.g. Μ-Markopoulo,
Μ-Α Larissa Industrial Area, Μ-Kokkina, temporary stations).
The description of the stations is similar to that for the Aghia Triada Metering Station noting that the PTZ
corrector replaces the flow calculator and the pressure and temperature transmitters, that there is no
MMS, and that the chemical composition for the purpose of calculating the GCV and the Energy is
obtained by the OPERATOR using information from a gas chromatograph at a neighboring entry or exit
point. For calculating compressibility, account is taken of the determined gas quality values entered into
the PTZ corrector.
Note: Only the Technical Specifications for those stations that pertain to each contract shall be added to
this Appendix.
TABLES 1-25 with the individual design and operation specifications, the metering equipment and the
installation details for all NGTS Metering/ Regulation Stations are attached to this Appendix 2.
NATURAL GAS TRANSMISSION CONTRACT - APPENDIX C2
Page 52 / 80
Unofficial translation
ENTRY POINTS
TABLE 1
AGHIA TRIADA U-3020
INDIVIDUAL DESIGN SPECIFICATIONS
DESIGN CODE
DESIGN PRESSURE
DESIGN TEMPERATURE
MINIMUM/ MAXIMUM ENTRY PRESSURE
MINIMUM/ MAXIMUM OFFTAKE PRESSURE
MINIMUM/ MAXIMUM ENTRY TEMPERATURE
ANSI B31.8
70 barg
-15 °C / +50 °C
38.4 barg / 66.4 barg
37.9 barg / 66.4 barg
+ 3°C / + 19°C
MINIMUM/ MAXIMUM OFFTAKE TEMPERATURE
OPERATING PRESSURE
OPERATING TEMPERATURE
MAXIMUM STATION CAPACITY
METER RUN NOMINAL CAPACITY
-
259777 Nm3/h
259777 Nm3/h
METERING EQUIPMENT
METER (EQUIPMENT) TYPE
Turbine meters
NUMBER OF INSTALLED METER RUNS
2
NUMBER OF INSTALLED CHROMATOGRAPHS
2
SUPPORTING EQUIPMENT TOTAL POSSIBLE ERROR
ENERGY UNCERTAINTY (FROM THE MANUFACTURER)
P=±0.15%. T=±0.14οC
±0.47%
INSTALLATION DETAILS
METER CAPACITY
G4000
METER DIAMETER
400mm
METER RUN DIAMETER
FLOW ALIGNMENT DEVICE DESIGN
400mm
ISO 5167 Type C. bundle of 19
tubes
Note:
Where 2 is indicated it means there is a backup metering device of the same type installed
Where 1+1 is indicated it means there is a backup metering device of a different type installed
Where 1+(1) is indicated it means that there is provision for backup metering device.
NATURAL GAS TRANSMISSION CONTRACT - APPENDIX C2
Page 53 / 80
Unofficial translation
TABLE 2
SIDIROKASTRO U-2010
INDIVIDUAL DESIGN SPECIFICATIONS
DESIGN CODE
DESIGN PRESSURE
DESIGN TEMPERATURE
MINIMUM/ MAXIMUM ENTRY PRESSURE
MINIMUM/ MAXIMUM OFFTAKE PRESSURE
MINIMUM/ MAXIMUM ENTRY TEMPERATURE
MINIMUM/ MAXIMUM OFFTAKE TEMPERATURE
OPERATING PRESSURE
OPERATING TEMPERATURE
STATION DESIGN CAPACITY
TECHNICALLY MAXIMUM STATION CAPACITY
METER RUN NOMINAL CAPACITY
ANSI B31.3 & B31.8
70 barg
-24 ºC / +80 ºC
47.75 barg / 55 barg
+6 ºC / +40 ºC
+6 ºC / +40 ºC
359550 Nm3/h
437000 Nm3/h
218500 Νm3/h
METERING EQUIPMENT
METER (EQUIPMENT) TYPE
Orifice meters
NUMBER OF INSTALLED METER RUNS
NUMBER OF INSTALLED CHROMATOGRAPHS
SUPPORTING EQUIPMENT TOTAL POSSIBLE ERROR
ENERGY UNCERTAINTY (FROM THE MANUFACTURER)
4
3
P=±0.15%. ΔP=±0.15%.
T=±0.14οC
±0.65%
INSTALLATION DETAILS
METER CAPACITY
-
METER DIAMETER
220 mm
METER RUN DIAMETER
400 mm
FLOW ALIGNMENT DEVICE DESIGN
-
Note:
Where 2 is indicated it means there is a backup metering device of the same type installed
Where 1+1 is indicated it means there is a backup metering device of a different type installed
Where 1+(1) is indicated it means that there is provision for backup metering device.
NATURAL GAS TRANSMISSION CONTRACT - APPENDIX C2
Page 54 / 80
Unofficial translation
EXIT POINTS
TABLE 1
LAVRIO U-3430
INDIVIDUAL DESIGN SPECIFICATIONS
DESIGN CODE
DESIGN PRESSURE
DESIGN TEMPERATURE
MINIMUM/ MAXIMUM ENTRY PRESSURE
MINIMUM/ MAXIMUM OFFTAKE PRESSURE
MINIMUM/ MAXIMUM ENTRY TEMPERATURE
MINIMUM/ MAXIMUM OFFTAKE TEMPERATURE
ASME VIII Div.1
40 barg
-10 ºC / +80 ºC
26.5 barg / 37.5 barg
25 barg / +3 ºC / +26 ºC
+3 ºC / +26 ºC
OPERATING PRESSURE
-
OPERATING TEMPERATURE
MAXIMUM STATION CAPACITY
METER RUN NOMINAL CAPACITY
ULTRASONIC METER RUN NOMINAL CAPACITY
-
240000 Nm3/h
80000 Nm3/h
19000 Νm3/h
METERING EQUIPMENT
METER (EQUIPMENT) TYPE
4 Orifice & 2 Ultrasonic Meters
NUMBER OF INSTALLED METER RUNS
NUMBER OF INSTALLED CHROMATOGRAPHS
SUPPORTING EQUIPMENT TOTAL POSSIBLE ERROR
ENERGY UNCERTAINTY (FROM THE MANUFACTURER)
4+2
2
P=±0.15%. ΔP=±0.15%.
T=±0.14οC
±0.65%
INSTALLATION DETAILS
METER CAPACITY
-
METER DIAMETER
150 mm
METER RUN DIAMETER
250 mm
FLOW ALIGNMENT DEVICE DESIGN
ISO 5167 Z3433
Note:
Where 2 is indicated it means there is a backup metering device of the same type installed
Where 1+1 is indicated it means there is a backup metering device of a different type installed
Where 1+(1) is indicated it means that there is provision for backup metering device.
NATURAL GAS TRANSMISSION CONTRACT - APPENDIX C2
Page 55 / 80
Unofficial translation
TABLE 2
KOMOTINI U-3570
INDIVIDUAL DESIGN SPECIFICATIONS
DESIGN CODE
DESIGN PRESSURE
DESIGN TEMPERATURE
MINIMUM/ MAXIMUM ENTRY PRESSURE
MINIMUM/ MAXIMUM OFFTAKE PRESSURE
MINIMUM/ MAXIMUM ENTRY TEMPERATURE
MINIMUM/ MAXIMUM OFFTAKE TEMPERATURE
ASME VIII Div.1
70 barg
-24 ºC / +80 ºC
40 barg / 55 barg
28 barg / +6 ºC / +24 ºC
+3 ºC / +26 ºC
OPERATING PRESSURE
-
OPERATING TEMPERATURE
-
MAXIMUM STATION CAPACITY
METER RUN NOMINAL CAPACITY
ULTRASONIC METER RUN NOMINAL CAPACITY
108000 Nm3/h
54000 Nm3/h
20000 Νm3/h
METERING EQUIPMENT
METER (EQUIPMENT) TYPE
3 Orifice meters & Ultrasonic
meters
NUMBER OF INSTALLED METER RUNS
NUMBER OF INSTALLED CHROMATOGRAPHS
SUPPORTING EQUIPMENT TOTAL POSSIBLE ERROR
ENERGY UNCERTAINTY (FROM THE MANUFACTURER)
3+2
2
P=±0.15%. ΔP=±0.15%.
T=±0.14οC
±0.65%
INSTALLATION DETAILS
METER CAPACITY
-
METER DIAMETER
115 mm
METER RUN DIAMETER
200 mm
FLOW ALIGNMENT DEVICE DESIGN
ISO 5167 Z3573
Note:
Where 2 is indicated it means there is a backup metering device of the same type installed
Where 1+1 is indicated it means there is a backup metering device of a different type installed
Where 1+(1) is indicated it means that there is provision for backup metering device.
NATURAL GAS TRANSMISSION CONTRACT - APPENDIX C2
Page 56 / 80
Unofficial translation
TABLE 3
KERATSINI U-3090
INDIVIDUAL DESIGN SPECIFICATIONS
DESIGN CODE
DESIGN PRESSURE
DESIGN TEMPERATURE
MINIMUM/ MAXIMUM ENTRY PRESSURE
MINIMUM/ MAXIMUM OFFTAKE PRESSURE
MINIMUM/ MAXIMUM ENTRY TEMPERATURE
MINIMUM/ MAXIMUM OFFTAKE TEMPERATURE
OPERATING PRESSURE
ANSI B31.8
40 barg
-15 ºC / +50 ºC
18 barg / 18.2 barg
17.6 barg / +3 ºC/ +3 ºC/ 17.6 barg
OPERATING TEMPERATURE
MAXIMUM STATION CAPACITY
METER RUN NOMINAL CAPACITY
-
102153 Nm3/h
102153 Nm3/h
METERING EQUIPMENT
METER (EQUIPMENT) TYPE
Turbine meters
NUMBER OF INSTALLED METER RUNS
2
NUMBER OF INSTALLED CHROMATOGRAPHS
2
SUPPORTING EQUIPMENT TOTAL POSSIBLE ERROR
ENERGY UNCERTAINTY (FROM THE MANUFACTURER)
P=±0.15%. T=±0.14οC
±0.47%
INSTALLATION DETAILS
METER CAPACITY
G4000
METER DIAMETER
400 mm
METER RUN DIAMETER
400 mm
FLOW ALIGNMENT DEVICE DESIGN
-
Note:
Where 2 is indicated it means there is a backup metering device of the same type installed
Where 1+1 is indicated it means there is a backup metering device of a different type installed
Where 1+(1) is indicated it means that there is provision for backup metering device.
NATURAL GAS TRANSMISSION CONTRACT - APPENDIX C2
Page 57 / 80
Unofficial translation
TABLE 4
IRONAS U-6020
INDIVIDUAL DESIGN SPECIFICATIONS
DESIGN CODE
DESIGN PRESSURE
DESIGN TEMPERATURE
MINIMUM/ MAXIMUM ENTRY PRESSURE
MINIMUM/ MAXIMUM OFFTAKE PRESSURE
ANSI B31.8
70 barg
-29 ºC / +80 ºC
25.5 barg / 66.4 barg
25 barg / -
MINIMUM/ MAXIMUM ENTRY TEMPERATURE
-
MINIMUM/ MAXIMUM OFFTAKE TEMPERATURE
-
OPERATING PRESSURE
45 barg
OPERATING TEMPERATURE
MAXIMUM STATION CAPACITY
METER RUN NOMINAL CAPACITY
+10ºC
40000 Nm3/h
40000 Nm3/h
METERING EQUIPMENT
METER (EQUIPMENT) TYPE
Ultrasonic meters
NUMBER OF INSTALLED METER RUNS
2
NUMBER OF INSTALLED CHROMATOGRAPHS
-
SUPPORTING EQUIPMENT TOTAL POSSIBLE ERROR
P=±0.15%. T=±0.14οC
ENERGY UNCERTAINTY (FROM THE MANUFACTURER)
-
INSTALLATION DETAILS
METER CAPACITY
2500 m3/h
METER DIAMETER
200 mm
METER RUN DIAMETER
200 mm
FLOW ALIGNMENT DEVICE DESIGN
-
Note:
Where 2 is indicated it means there is a backup metering device of the same type installed
Where 1+1 is indicated it means there is a backup metering device of a different type installed
Where 1+(1) is indicated it means that there is provision for backup metering device.
NATURAL GAS TRANSMISSION CONTRACT - APPENDIX C2
Page 58 / 80
Unofficial translation
TABLE 5
XANTHI ΤΜ3-Β
INDIVIDUAL DESIGN SPECIFICATIONS
DESIGN CODE
DESIGN PRESSURE
DESIGN TEMPERATURE
MINIMUM/ MAXIMUM ENTRY PRESSURE
MINIMUM/ MAXIMUM OFFTAKE PRESSURE
MINIMUM/ MAXIMUM ENTRY TEMPERATURE
MINIMUM/ MAXIMUM OFFTAKE TEMPERATURE
OPERATING PRESSURE
ANSI B31.8
70 barg
-24 ºC / +80 ºC
35 barg / 66.4 barg
+5 ºC / +25 ºC
16.7 barg
OPERATING TEMPERATURE
MAXIMUM STATION CAPACITY
METER RUN NOMINAL CAPACITY
-
20000 Nm3/h
20000 Nm3/h
METERING EQUIPMENT
METER (EQUIPMENT) TYPE
Turbine meter
NUMBER OF INSTALLED METER RUNS
1+(1)
NUMBER OF INSTALLED CHROMATOGRAPHS
SUPPORTING EQUIPMENT TOTAL POSSIBLE ERROR
ENERGY UNCERTAINTY (FROM THE MANUFACTURER)
P=±0.3%. T=±0.3οC
±1.15%
INSTALLATION DETAILS
METER CAPACITY
G 1000
METER DIAMETER
150 mm
METER RUN DIAMETER
150 mm
FLOW ALIGNMENT DEVICE DESIGN
-
Note:
Where 2 is indicated it means there is a backup metering device of the same type installed
Where 1+1 is indicated it means there is a backup metering device of a different type installed
Where 1+(1) is indicated it means that there is provision for backup metering device.
NATURAL GAS TRANSMISSION CONTRACT - APPENDIX C2
Page 59 / 80
Unofficial translation
TABLE 6
KAVALA ΤΜ4-Α
INDIVIDUAL DESIGN SPECIFICATIONS
DESIGN CODE
DESIGN PRESSURE
DESIGN TEMPERATURE
MINIMUM/ MAXIMUM ENTRY PRESSURE
MINIMUM/ MAXIMUM OFFTAKE PRESSURE
MINIMUM/ MAXIMUM ENTRY TEMPERATURE
MINIMUM/ MAXIMUM OFFTAKE TEMPERATURE
OPERATING PRESSURE
ANSI B31.8
70 barg
-24 ºC / +80 ºC
35 barg / 66.4 barg
+5 ºC / +25 ºC
16.7 barg
OPERATING TEMPERATURE
MAXIMUM STATION CAPACITY
METER RUN NOMINAL CAPACITY
-
10000 Nm3/h
10000 Nm3/h
METERING EQUIPMENT
METER (EQUIPMENT) TYPE
Turbine meter
NUMBER OF INSTALLED METER RUNS
1+(1)
NUMBER OF INSTALLED CHROMATOGRAPHS
SUPPORTING EQUIPMENT TOTAL POSSIBLE ERROR
ENERGY UNCERTAINTY (FROM THE MANUFACTURER)
P=±0.3%. T=±0.3οC
±1.15%
INSTALLATION DETAILS
METER CAPACITY
G 400
METER DIAMETER
150 mm
METER RUN DIAMETER
150 mm
FLOW ALIGNMENT DEVICE DESIGN
-
Note:
Where 2 is indicated it means there is a backup metering device of the same type installed
Where 1+1 is indicated it means there is a backup metering device of a different type installed
Where 1+(1) is indicated it means that there is provision for backup metering device.
NATURAL GAS TRANSMISSION CONTRACT - APPENDIX C2
Page 60 / 80
Unofficial translation
TABLE 7
SERRES ΤΜ3-Α
INDIVIDUAL DESIGN SPECIFICATIONS
DESIGN CODE
DESIGN PRESSURE
DESIGN TEMPERATURE
MINIMUM/ MAXIMUM ENTRY PRESSURE
MINIMUM/ MAXIMUM OFFTAKE PRESSURE
MINIMUM/ MAXIMUM ENTRY TEMPERATURE
MINIMUM/ MAXIMUM OFFTAKE TEMPERATURE
OPERATING PRESSURE
ANSI B31.8
70 barg
-24 ºC / +80 ºC
35 barg / 66.4 barg
+5 ºC / +25 ºC
16.7 barg
OPERATING TEMPERATURE
MAXIMUM STATION CAPACITY
METER RUN NOMINAL CAPACITY
-
20000 Nm3/h
20000 Nm3/h
METERING EQUIPMENT
METER (EQUIPMENT) TYPE
Turbine meter
NUMBER OF INSTALLED METER RUNS
1+(1)
NUMBER OF INSTALLED CHROMATOGRAPHS
SUPPORTING EQUIPMENT TOTAL POSSIBLE ERROR
ENERGY UNCERTAINTY (FROM THE MANUFACTURER)
P=±0.3%. T=±0.3οC
±1.15%
INSTALLATION DETAILS
METER CAPACITY
G 1000
METER DIAMETER
150 mm
METER RUN DIAMETER
150 mm
FLOW ALIGNMENT DEVICE DESIGN
-
Note:
Where 2 is indicated it means there is a backup metering device of the same type installed
Where 1+1 is indicated it means there is a backup metering device of a different type installed
Where 1+(1) is indicated it means that there is provision for backup metering device.
NATURAL GAS TRANSMISSION CONTRACT - APPENDIX C2
Page 61 / 80
Unofficial translation
TABLE 8
KOMOTINI ΤΜ3-C
INDIVIDUAL DESIGN SPECIFICATIONS
DESIGN CODE
DESIGN PRESSURE
DESIGN TEMPERATURE
MINIMUM/ MAXIMUM ENTRY PRESSURE
MINIMUM/ MAXIMUM OFFTAKE PRESSURE
MINIMUM/ MAXIMUM ENTRY TEMPERATURE
MINIMUM/ MAXIMUM OFFTAKE TEMPERATURE
OPERATING PRESSURE
ANSI B31.8
70 barg
-24 ºC / +80 ºC
35 barg / 66.4 barg
+5 ºC / +25 ºC
16.7 barg
OPERATING TEMPERATURE
MAXIMUM STATION CAPACITY
METER RUN NOMINAL CAPACITY
-
20000 Nm3/h
20000 Nm3/h
METERING EQUIPMENT
METER (EQUIPMENT) TYPE
Turbine meter
NUMBER OF INSTALLED METER RUNS
1+(1)
NUMBER OF INSTALLED CHROMATOGRAPHS
SUPPORTING EQUIPMENT TOTAL POSSIBLE ERROR
ENERGY UNCERTAINTY (FROM THE MANUFACTURER)
P=±0.3%. T=±0.3οC
±1.15%
INSTALLATION DETAILS
METER CAPACITY
G 1000
METER DIAMETER
150 mm
METER RUN DIAMETER
150 mm
FLOW ALIGNMENT DEVICE DESIGN
-
Note:
Where 2 is indicated it means there is a backup metering device of the same type installed
Where 1+1 is indicated it means there is a backup metering device of a different type installed
Where 1+(1) is indicated it means that there is provision for backup metering device.
NATURAL GAS TRANSMISSION CONTRACT - APPENDIX C2
Page 62 / 80
Unofficial translation
TABLE 9
MARKOPOULO TM2
INDIVIDUAL DESIGN SPECIFICATIONS
DESIGN CODE
DESIGN PRESSURE
DESIGN TEMPERATURE
MINIMUM/ MAXIMUM ENTRY PRESSURE
MINIMUM/ MAXIMUM OFFTAKE PRESSURE
MINIMUM/ MAXIMUM ENTRY TEMPERATURE
MINIMUM/ MAXIMUM OFFTAKE TEMPERATURE
OPERATING PRESSURE
ANSI B31.8
70 barg
-24 ºC / +80 ºC
35 barg / 66.4 barg
+5 ºC / 16.7 barg
OPERATING TEMPERATURE
MAXIMUM STATION CAPACITY
METER RUN NOMINAL CAPACITY
-
28800 Nm3/h
28800 Nm3/h
METERING EQUIPMENT
METER (EQUIPMENT) TYPE
Turbine meter & Rotary meter
NUMBER OF INSTALLED METER RUNS
1+1
NUMBER OF INSTALLED CHROMATOGRAPHS
SUPPORTING EQUIPMENT TOTAL POSSIBLE ERROR
ENERGY UNCERTAINTY (FROM THE MANUFACTURER)
P=±0.3%. T=±0.3οC
±1.15%
INSTALLATION DETAILS
METER CAPACITY
G 1000 . G 160 (Rotary)
METER DIAMETER
150 mm
METER RUN DIAMETER
150 mm
FLOW ALIGNMENT DEVICE DESIGN
-
Note:
Where 2 is indicated it means there is a backup metering device of the same type installed
Where 1+1 is indicated it means there is a backup metering device of a different type installed
Where 1+(1) is indicated it means that there is provision for backup metering device.
NATURAL GAS TRANSMISSION CONTRACT - APPENDIX C2
Page 63 / 80
Unofficial translation
TABLE 10
NORTHERN ATHENS U-2910
INDIVIDUAL DESIGN SPECIFICATIONS
DESIGN CODE
DESIGN PRESSURE
DESIGN TEMPERATURE
MINIMUM/ MAXIMUM ENTRY PRESSURE
MINIMUM/ MAXIMUM OFFTAKE PRESSURE
MINIMUM/ MAXIMUM ENTRY TEMPERATURE
MINIMUM/ MAXIMUM OFFTAKE TEMPERATURE
OPERATING PRESSURE
ANSI B31.8
70 barg
-15 ºC / +50 ºC
32.1 barg / 66.4 barg
-3 ºC / +24 ºC
+3 ºC / +7 ºC
16.7 barg
OPERATING TEMPERATURE
MAXIMUM STATION CAPACITY
METER RUN NOMINAL CAPACITY
-
110219 Nm3/h
110219 Nm3/h
METERING EQUIPMENT
METER (EQUIPMENT) TYPE
Turbine meters
NUMBER OF INSTALLED METER RUNS
2
NUMBER OF INSTALLED CHROMATOGRAPHS
1
SUPPORTING EQUIPMENT TOTAL POSSIBLE ERROR
ENERGY UNCERTAINTY (FROM THE MANUFACTURER)
P=±0.15%. T=±0.14οC
±0.47%
INSTALLATION DETAILS
METER CAPACITY
G4000
METER DIAMETER
400mm
METER RUN DIAMETER
FLOW ALIGNMENT DEVICE DESIGN
400mm
ISO 5167 Type C. bundle of 19
tubes
Note:
Where 2 is indicated it means there is a backup metering device of the same type installed
Where 1+1 is indicated it means there is a backup metering device of a different type installed
Where 1+(1) is indicated it means that there is provision for backup metering device.
NATURAL GAS TRANSMISSION CONTRACT - APPENDIX C2
Page 64 / 80
Unofficial translation
TABLE 11
THRIASIO U-2960
INDIVIDUAL DESIGN SPECIFICATIONS
DESIGN CODE
DESIGN PRESSURE
DESIGN TEMPERATURE
MINIMUM/ MAXIMUM ENTRY PRESSURE
MINIMUM/ MAXIMUM OFFTAKE PRESSURE
MINIMUM/ MAXIMUM ENTRY TEMPERATURE
MINIMUM/ MAXIMUM OFFTAKE TEMPERATURE
OPERATING PRESSURE
ANSI B31.8
70 barg
-15 ºC / +50 ºC
36.5 barg / 66.4 barg
-3 ºC / +3 ºC / 16.7 barg
OPERATING TEMPERATURE
MAXIMUM STATION CAPACITY
METER RUN NOMINAL CAPACITY
-
50705 Nm3/h
50705 Nm3/h
METERING EQUIPMENT
METER (EQUIPMENT) TYPE
Turbine meters
NUMBER OF INSTALLED METER RUNS
2
NUMBER OF INSTALLED CHROMATOGRAPHS
1
SUPPORTING EQUIPMENT TOTAL POSSIBLE ERROR
ENERGY UNCERTAINTY (FROM THE MANUFACTURER)
P=±0.15%. T=±0.14οC
±0.47%
INSTALLATION DETAILS
METER CAPACITY
G2500
METER DIAMETER
250mm
METER RUN DIAMETER
FLOW ALIGNMENT DEVICE DESIGN
250mm
ISO 5167 Type C. bundle of 19
tubes
Note:
Where 2 is indicated it means there is a backup metering device of the same type installed
Where 1+1 is indicated it means there is a backup metering device of a different type installed
Where 1+(1) is indicated it means that there is provision for backup metering device.
NATURAL GAS TRANSMISSION CONTRACT - APPENDIX C2
Page 65 / 80
Unofficial translation
TABLE 12
EASTERN ATHENS U-2940
INDIVIDUAL DESIGN SPECIFICATIONS
DESIGN CODE
DESIGN PRESSURE
DESIGN TEMPERATURE
MINIMUM/ MAXIMUM ENTRY PRESSURE
MINIMUM/ MAXIMUM OFFTAKE PRESSURE
MINIMUM/ MAXIMUM ENTRY TEMPERATURE
MINIMUM/ MAXIMUM OFFTAKE TEMPERATURE
OPERATING PRESSURE
ANSI B31.8
40 barg
-15 ºC / +50 ºC
27.6 barg / 37.7 barg
-2 ºC / +24 ºC
+3 ºC / +11 ºC
16.7 barg
OPERATING TEMPERATURE
MAXIMUM STATION CAPACITY
METER RUN NOMINAL CAPACITY
-
110219 Nm3/h
110219 Nm3/h
METERING EQUIPMENT
METER (EQUIPMENT) TYPE
Turbine meters
NUMBER OF INSTALLED METER RUNS
2
NUMBER OF INSTALLED CHROMATOGRAPHS
1
SUPPORTING EQUIPMENT TOTAL POSSIBLE ERROR
ENERGY UNCERTAINTY (FROM THE MANUFACTURER)
P=±0.15%. T=±0.14οC
±0.47%
INSTALLATION DETAILS
METER CAPACITY
G4000
METER DIAMETER
400mm
METER RUN DIAMETER
FLOW ALIGNMENT DEVICE DESIGN
400mm
ISO 5167 Type C. bundle of 19
tubes
Note:
Where 2 is indicated it means there is a backup metering device of the same type installed
Where 1+1 is indicated it means there is a backup metering device of a different type installed
Where 1+(1) is indicated it means that there is provision for backup metering device.
NATURAL GAS TRANSMISSION CONTRACT - APPENDIX C2
Page 66 / 80
Unofficial translation
TABLE 13
ASPROPIRGOS * U-2970
INDIVIDUAL DESIGN SPECIFICATIONS
DESIGN CODE
DESIGN PRESSURE
DESIGN TEMPERATURE
MINIMUM/ MAXIMUM ENTRY PRESSURE
MINIMUM/ MAXIMUM OFFTAKE PRESSURE
MINIMUM/ MAXIMUM ENTRY TEMPERATURE
MINIMUM/ MAXIMUM OFFTAKE TEMPERATURE
OPERATING PRESSURE
ANSI B31.8
70 barg
-15 ºC / +50 ºC
30 barg / 66.4 barg
-3 ºC / +3 ºC / 28.9 barg
OPERATING TEMPERATURE
MAXIMUM STATION CAPACITY
METER RUN NOMINAL CAPACITY
-
100150 Nm3/h
100150 Nm3/h
METERING EQUIPMENT
METER (EQUIPMENT) TYPE
Turbine meters
NUMBER OF INSTALLED METER RUNS
2
NUMBER OF INSTALLED CHROMATOGRAPHS
1
SUPPORTING EQUIPMENT TOTAL POSSIBLE ERROR
ENERGY UNCERTAINTY (FROM THE MANUFACTURER)
P=±0.15%. T=±0.14οC
±0.47%
INSTALLATION DETAILS
METER CAPACITY
G2500
METER DIAMETER
300mm
METER RUN DIAMETER
FLOW ALIGNMENT DEVICE DESIGN
300mm
ISO 5167 Type C. bundle of 19
tubes
* there is a isolated metering station with nitrogen under pressure.
Note:
Where 2 is indicated it means there is a backup metering device of the same type installed
Where 1+1 is indicated it means there is a backup metering device of a different type installed
Where 1+(1) is indicated it means that there is provision for backup metering device.
NATURAL GAS TRANSMISSION CONTRACT - APPENDIX C2
Page 67 / 80
Unofficial translation
TABLE 14
WESTERN ATHENS U-2990
INDIVIDUAL DESIGN SPECIFICATIONS
DESIGN CODE
DESIGN PRESSURE
DESIGN TEMPERATURE
MINIMUM/ MAXIMUM ENTRY PRESSURE
MINIMUM/ MAXIMUM OFFTAKE PRESSURE
MINIMUM/ MAXIMUM ENTRY TEMPERATURE
MINIMUM/ MAXIMUM OFFTAKE TEMPERATURE
OPERATING PRESSURE
ANSI B31.8
70 barg
-15 ºC / +50 ºC
26.8 barg / 66.4 barg
-4 ºC /
+3 ºC / 16.7 barg
OPERATING TEMPERATURE
MAXIMUM STATION CAPACITY
METER RUN NOMINAL CAPACITY
-
110213 Nm3/h
110213 Nm3/h
METERING EQUIPMENT
METER (EQUIPMENT) TYPE
Turbine meters
NUMBER OF INSTALLED METER RUNS
2
NUMBER OF INSTALLED CHROMATOGRAPHS
1
SUPPORTING EQUIPMENT TOTAL POSSIBLE ERROR
ENERGY UNCERTAINTY (FROM THE MANUFACTURER)
P=±0.15%. T=±0.14οC
±0.47%
INSTALLATION DETAILS
METER CAPACITY
G4000
METER DIAMETER
400mm
METER RUN DIAMETER
FLOW ALIGNMENT DEVICE DESIGN
400mm
ISO 5167 Type C. bundle of 19
tubes
Note:
Where 2 is indicated it means there is a backup metering device of the same type installed
Where 1+1 is indicated it means there is a backup metering device of a different type installed
Where 1+(1) is indicated it means that there is provision for backup metering device.
NATURAL GAS TRANSMISSION CONTRACT - APPENDIX C2
Page 68 / 80
Unofficial translation
TABLE 15
INOFITA U-2880
INDIVIDUAL DESIGN SPECIFICATIONS
DESIGN CODE
DESIGN PRESSURE
DESIGN TEMPERATURE
MINIMUM/ MAXIMUM ENTRY PRESSURE
MINIMUM/ MAXIMUM OFFTAKE PRESSURE
MINIMUM/ MAXIMUM ENTRY TEMPERATURE
MINIMUM/ MAXIMUM OFFTAKE TEMPERATURE
OPERATING PRESSURE
ANSI B31.8
70 barg
-15 ºC / +50 ºC
36.3 barg / 66.4 barg
+5 ºC / +24 ºC
+3 ºC / +7 ºC
16.7 barg
OPERATING TEMPERATURE
MAXIMUM STATION CAPACITY
METER RUN NOMINAL CAPACITY
-
26508 Nm3/h
26508 Nm3/h
METERING EQUIPMENT
METER (EQUIPMENT) TYPE
Turbine meters
NUMBER OF INSTALLED METER RUNS
2
NUMBER OF INSTALLED CHROMATOGRAPHS
1
SUPPORTING EQUIPMENT TOTAL POSSIBLE ERROR
ENERGY UNCERTAINTY (FROM THE MANUFACTURER)
P=±0.15%. T=±0.14οC
±0.47%
INSTALLATION DETAILS
METER CAPACITY
G1000
METER DIAMETER
200mm
METER RUN DIAMETER
FLOW ALIGNMENT DEVICE DESIGN
200mm
ISO 5167 Type C. bundle of 19
tubes
Note:
Where 2 is indicated it means there is a backup metering device of the same type installed
Where 1+1 is indicated it means there is a backup metering device of a different type installed
Where 1+(1) is indicated it means that there is provision for backup metering device.
NATURAL GAS TRANSMISSION CONTRACT - APPENDIX C2
Page 69 / 80
Unofficial translation
TABLE 16
VFL U-2170
INDIVIDUAL DESIGN SPECIFICATIONS
DESIGN CODE
DESIGN PRESSURE
DESIGN TEMPERATURE
MINIMUM/ MAXIMUM ENTRY PRESSURE
MINIMUM/ MAXIMUM OFFTAKE PRESSURE
MINIMUM/ MAXIMUM ENTRY TEMPERATURE
MINIMUM/ MAXIMUM OFFTAKE TEMPERATURE
OPERATING PRESSURE
ANSI B31.8
70 barg
-15 ºC / +50 ºC
33.2 barg / 55 barg
32.7 barg / +7 ºC / -
OPERATING TEMPERATURE
MAXIMUM STATION CAPACITY
METER RUN NOMINAL CAPACITY
-
24309 Nm3/h
24309 Nm3/h
METERING EQUIPMENT
METER (EQUIPMENT) TYPE
Turbine meters
NUMBER OF INSTALLED METER RUNS
2
NUMBER OF INSTALLED CHROMATOGRAPHS
1
SUPPORTING EQUIPMENT TOTAL POSSIBLE ERROR
ENERGY UNCERTAINTY (FROM THE MANUFACTURER)
P=±0.15%. T=±0.14οC
±0.47%
INSTALLATION DETAILS
METER CAPACITY
G650
METER DIAMETER
150mm
METER RUN DIAMETER
150mm
FLOW ALIGNMENT DEVICE DESIGN
-
Note:
Where 2 is indicated it means there is a backup metering device of the same type installed
Where 1+1 is indicated it means there is a backup metering device of a different type installed
Where 1+(1) is indicated it means that there is provision for backup metering device.
NATURAL GAS TRANSMISSION CONTRACT - APPENDIX C2
Page 70 / 80
Unofficial translation
TABLE 17
NORTHERN THESSALONIKI U-2240
INDIVIDUAL DESIGN SPECIFICATIONS
DESIGN CODE
DESIGN PRESSURE
DESIGN TEMPERATURE
MINIMUM/ MAXIMUM ENTRY PRESSURE
MINIMUM/ MAXIMUM OFFTAKE PRESSURE
MINIMUM/ MAXIMUM ENTRY TEMPERATURE
MINIMUM/ MAXIMUM OFFTAKE TEMPERATURE
OPERATING PRESSURE
ANSI B31.8
70 barg
-15 ºC / +50 ºC
35.6 barg / 55 barg
+6 ºC / +3 ºC / 16.7 barg
OPERATING TEMPERATURE
MAXIMUM STATION CAPACITY
METER RUN NOMINAL CAPACITY
-
72527 Nm3/h
72527 Nm3/h
METERING EQUIPMENT
METER (EQUIPMENT) TYPE
Turbine meters
NUMBER OF INSTALLED METER RUNS
2
NUMBER OF INSTALLED CHROMATOGRAPHS
1
SUPPORTING EQUIPMENT TOTAL POSSIBLE ERROR
ENERGY UNCERTAINTY (FROM THE MANUFACTURER)
P=±0.15%. T=±0.14οC
±0.47%
INSTALLATION DETAILS
METER CAPACITY
G2500
METER DIAMETER
300mm
METER RUN DIAMETER
FLOW ALIGNMENT DEVICE DESIGN
300mm
ISO 5167 Type C. bundle of 19
tubes
Note:
Where 2 is indicated it means there is a backup metering device of the same type installed
Where 1+1 is indicated it means there is a backup metering device of a different type installed
Where 1+(1) is indicated it means that there is provision for backup metering device.
NATURAL GAS TRANSMISSION CONTRACT - APPENDIX C2
Page 71 / 80
Unofficial translation
TABLE 18
EASTERN THESSALONIKI U-2220
INDIVIDUAL DESIGN SPECIFICATIONS
DESIGN CODE
DESIGN PRESSURE
DESIGN TEMPERATURE
MINIMUM/ MAXIMUM ENTRY PRESSURE
MINIMUM/ MAXIMUM OFFTAKE PRESSURE
MINIMUM/ MAXIMUM ENTRY TEMPERATURE
MINIMUM/ MAXIMUM OFFTAKE TEMPERATURE
OPERATING PRESSURE
ANSI B31.8
70 barg
-15 ºC / +50 ºC
34.2 barg / 55 barg
+6 ºC / +24 ºC
+3 ºC / +7 ºC
16.7 barg
OPERATING TEMPERATURE
MAXIMUM STATION CAPACITY
METER RUN NOMINAL CAPACITY
-
72527 Nm3/h
72527 Nm3/h
METERING EQUIPMENT
METER (EQUIPMENT) TYPE
Turbine meters
NUMBER OF INSTALLED METER RUNS
2
NUMBER OF INSTALLED CHROMATOGRAPHS
1
SUPPORTING EQUIPMENT TOTAL POSSIBLE ERROR
ENERGY UNCERTAINTY (FROM THE MANUFACTURER)
P=±0.15%. T=±0.14οC
±0.47%
INSTALLATION DETAILS
METER CAPACITY
G2500
METER DIAMETER
300mm
METER RUN DIAMETER
FLOW ALIGNMENT DEVICE DESIGN
300mm
ISO 5167 Type C. bundle of 19
tubes
Note:
Where 2 is indicated it means there is a backup metering device of the same type installed
Where 1+1 is indicated it means there is a backup metering device of a different type installed
Where 1+(1) is indicated it means that there is provision for backup metering device.
NATURAL GAS TRANSMISSION CONTRACT - APPENDIX C2
Page 72 / 80
Unofficial translation
TABLE 19
PLATY IMATHIAS U-2410
INDIVIDUAL DESIGN SPECIFICATIONS
DESIGN CODE
DESIGN PRESSURE
DESIGN TEMPERATURE
MINIMUM/ MAXIMUM ENTRY PRESSURE
MINIMUM/ MAXIMUM OFFTAKE PRESSURE
MINIMUM/ MAXIMUM ENTRY TEMPERATURE
MINIMUM/ MAXIMUM OFFTAKE TEMPERATURE
OPERATING PRESSURE
ANSI B31.8
70 barg
-15 ºC / +50 ºC
43.8 barg / 66.4 barg
+10 ºC / +24 ºC
+3 ºC / +7 ºC
16.7 barg
OPERATING TEMPERATURE
MAXIMUM STATION CAPACITY
METER RUN NOMINAL CAPACITY
-
21488 Nm3/h
21488 Nm3/h
METERING EQUIPMENT
METER (EQUIPMENT) TYPE
Turbine meters
NUMBER OF INSTALLED METER RUNS
2
NUMBER OF INSTALLED CHROMATOGRAPHS
1
SUPPORTING EQUIPMENT TOTAL POSSIBLE ERROR
ENERGY UNCERTAINTY (FROM THE MANUFACTURER)
P=±0.15%. T=±0.14οC
±0.47%
INSTALLATION DETAILS
METER CAPACITY
G1000
METER DIAMETER
200mm
METER RUN DIAMETER
FLOW ALIGNMENT DEVICE DESIGN
200mm
ISO 5167 Type C. bundle of 19
tubes
Note:
Where 2 is indicated it means there is a backup metering device of the same type installed
Where 1+1 is indicated it means there is a backup metering device of a different type installed
Where 1+(1) is indicated it means that there is provision for backup metering device.
NATURAL GAS TRANSMISSION CONTRACT - APPENDIX C2
Page 73 / 80
Unofficial translation
TABLE 20
ΕΚΟ U-2250
INDIVIDUAL DESIGN SPECIFICATIONS
DESIGN CODE
DESIGN PRESSURE
DESIGN TEMPERATURE
MINIMUM/ MAXIMUM ENTRY PRESSURE
MINIMUM/ MAXIMUM OFFTAKE PRESSURE
MINIMUM/ MAXIMUM ENTRY TEMPERATURE
MINIMUM/ MAXIMUM OFFTAKE TEMPERATURE
OPERATING PRESSURE
ANSI B31.8
70 barg
-15 ºC / +50 ºC
39 barg / 55 barg
+6 ºC / +4 ºC / +18 ºC
34.5 barg
OPERATING TEMPERATURE
MAXIMUM STATION CAPACITY
METER RUN NOMINAL CAPACITY
-
18027 Nm3/h
18027 Nm3/h
METERING EQUIPMENT
METER (EQUIPMENT) TYPE
Turbine meters
NUMBER OF INSTALLED METER RUNS
2
NUMBER OF INSTALLED CHROMATOGRAPHS
1
SUPPORTING EQUIPMENT TOTAL POSSIBLE ERROR
ENERGY UNCERTAINTY (FROM THE MANUFACTURER)
P=±0.15%. T=±0.14οC
±0.47%
INSTALLATION DETAILS
METER CAPACITY
G400
METER DIAMETER
150mm
METER RUN DIAMETER
FLOW ALIGNMENT DEVICE DESIGN
150mm
ISO 5167 Type C. bundle of 19
tubes
Note:
Where 2 is indicated it means there is a backup metering device of the same type installed
Where 1+1 is indicated it means there is a backup metering device of a different type installed
Where 1+(1) is indicated it means that there is provision for backup metering device.
NATURAL GAS TRANSMISSION CONTRACT - APPENDIX C2
Page 74 / 80
Unofficial translation
TABLE 21
NORTHERN LARISSA U-2520
INDIVIDUAL DESIGN SPECIFICATIONS
DESIGN CODE
DESIGN PRESSURE
DESIGN TEMPERATURE
MINIMUM/ MAXIMUM ENTRY PRESSURE
MINIMUM/ MAXIMUM OFFTAKE PRESSURE
MINIMUM/ MAXIMUM ENTRY TEMPERATURE
MINIMUM/ MAXIMUM OFFTAKE TEMPERATURE
OPERATING PRESSURE
ANSI B31.8
70 barg
-15 ºC / +50 ºC
45.4 barg / 66.4 barg
+8 ºC / +3 ºC / 16.7 barg
OPERATING TEMPERATURE
MAXIMUM STATION CAPACITY
METER RUN NOMINAL CAPACITY
-
25910 Nm3/h
25910 Nm3/h
METERING EQUIPMENT
METER (EQUIPMENT) TYPE
Turbine meters
NUMBER OF INSTALLED METER RUNS
2
NUMBER OF INSTALLED CHROMATOGRAPHS
1
SUPPORTING EQUIPMENT TOTAL POSSIBLE ERROR
ENERGY UNCERTAINTY (FROM THE MANUFACTURER)
P=±0.15%. T=±0.14οC
±0.47%
INSTALLATION DETAILS
METER CAPACITY
G1000
METER DIAMETER
200mm
METER RUN DIAMETER
FLOW ALIGNMENT DEVICE DESIGN
200mm
ISO 5167 Type C. bundle of 19
tubes
Note:
Where 2 is indicated it means there is a backup metering device of the same type installed
Where 1+1 is indicated it means there is a backup metering device of a different type installed
Where 1+(1) is indicated it means that there is provision for backup metering device.
NATURAL GAS TRANSMISSION CONTRACT - APPENDIX C2
Page 75 / 80
Unofficial translation
TABLE 22
SOUTHERN LARISSA U-2530
INDIVIDUAL DESIGN SPECIFICATIONS
DESIGN CODE
DESIGN PRESSURE
DESIGN TEMPERATURE
MINIMUM/ MAXIMUM ENTRY PRESSURE
MINIMUM/ MAXIMUM OFFTAKE PRESSURE
MINIMUM/ MAXIMUM ENTRY TEMPERATURE
MINIMUM/ MAXIMUM OFFTAKE TEMPERATURE
OPERATING PRESSURE
ANSI B31.8
70 barg
-15 ºC / +50 ºC
45.4 barg / 66.4 barg
+7 ºC / +24 ºC
+3 ºC / +7 ºC
16.7 barg
OPERATING TEMPERATURE
MAXIMUM STATION CAPACITY
METER RUN NOMINAL CAPACITY
-
25910 Nm3/h
25910 Nm3/h
METERING EQUIPMENT
METER (EQUIPMENT) TYPE
Turbine meters
NUMBER OF INSTALLED METER RUNS
2
NUMBER OF INSTALLED CHROMATOGRAPHS
1
SUPPORTING EQUIPMENT TOTAL POSSIBLE ERROR
ENERGY UNCERTAINTY (FROM THE MANUFACTURER)
P=±0.15%. T=±0.14οC
±0.47%
INSTALLATION DETAILS
METER CAPACITY
G1000
METER DIAMETER
200mm
METER RUN DIAMETER
FLOW ALIGNMENT DEVICE DESIGN
200mm
ISO 5167 Type C. bundle of 19
tubes
Note:
Where 2 is indicated it means there is a backup metering device of the same type installed
Where 1+1 is indicated it means there is a backup metering device of a different type installed
Where 1+(1) is indicated it means that there is provision for backup metering device.
NATURAL GAS TRANSMISSION CONTRACT - APPENDIX C2
Page 76 / 80
Unofficial translation
TABLE 23
VOLOS U-2680
INDIVIDUAL DESIGN SPECIFICATIONS
DESIGN CODE
DESIGN PRESSURE
DESIGN TEMPERATURE
MINIMUM/ MAXIMUM ENTRY PRESSURE
MINIMUM/ MAXIMUM OFFTAKE PRESSURE
MINIMUM/ MAXIMUM ENTRY TEMPERATURE
MINIMUM/ MAXIMUM OFFTAKE TEMPERATURE
OPERATING PRESSURE
ANSI B31.8
70 barg
-15 ºC / +50 ºC
45.3 barg / 66.4 barg
+6 ºC / +3 ºC / 16.7 barg
OPERATING TEMPERATURE
MAXIMUM STATION CAPACITY
METER RUN NOMINAL CAPACITY
-
51643 Nm3/h
51643 Nm3/h
METERING EQUIPMENT
METER (EQUIPMENT) TYPE
Turbine meters
NUMBER OF INSTALLED METER RUNS
2
NUMBER OF INSTALLED CHROMATOGRAPHS
1
SUPPORTING EQUIPMENT TOTAL POSSIBLE ERROR
ENERGY UNCERTAINTY (FROM THE MANUFACTURER)
P=±0.15%. T=±0.14οC
±0.47%
INSTALLATION DETAILS
METER CAPACITY
G1600
METER DIAMETER
250mm
METER RUN DIAMETER
FLOW ALIGNMENT DEVICE DESIGN
250mm
ISO 5167 Type C. bundle of 19
tubes
Note:
Where 2 is indicated it means there is a backup metering device of the same type installed
Where 1+1 is indicated it means there is a backup metering device of a different type installed
Where 1+(1) is indicated it means that there is provision for backup metering device.
NATURAL GAS TRANSMISSION CONTRACT - APPENDIX C2
Page 77 / 80
Unofficial translation
TABLE 24
LARISSA INDUSTRIAL AREA U-2515
INDIVIDUAL DESIGN SPECIFICATIONS
DESIGN CODE
DESIGN PRESSURE
DESIGN TEMPERATURE
MINIMUM/ MAXIMUM ENTRY PRESSURE
MINIMUM/ MAXIMUM OFFTAKE PRESSURE
MINIMUM/ MAXIMUM ENTRY TEMPERATURE
MINIMUM/ MAXIMUM OFFTAKE TEMPERATURE
OPERATING PRESSURE
ΕΝ 1776
70 barg
-24 ºC / +60 ºC
35 barg / 66.4 barg
+5 ºC / +25 ºC
16.7 barg
OPERATING TEMPERATURE
MAXIMUM STATION CAPACITY
METER RUN NOMINAL CAPACITY
-
10000 Nm3/h
10000 Nm3/h
METERING EQUIPMENT
METER (EQUIPMENT) TYPE
Turbine meters
NUMBER OF INSTALLED METER RUNS
2
NUMBER OF INSTALLED CHROMATOGRAPHS
-
SUPPORTING EQUIPMENT TOTAL POSSIBLE ERROR
-
ENERGY UNCERTAINTY (FROM THE MANUFACTURER)
-
INSTALLATION DETAILS
METER CAPACITY
G 400
METER DIAMETER
150 mm
METER RUN DIAMETER
-
FLOW ALIGNMENT DEVICE DESIGN
-
Note:
Where 2 is indicated it means there is a backup metering device of the same type installed
Where 1+1 is indicated it means there is a backup metering device of a different type installed
Where 1+(1) is indicated it means that there is provision for backup metering device.
NATURAL GAS TRANSMISSION CONTRACT - APPENDIX C2
Page 78 / 80
Unofficial translation
TABLE 25
ΚΟΚΚΙΝΑ U-2670
INDIVIDUAL DESIGN SPECIFICATIONS
DESIGN CODE
DESIGN PRESSURE
DESIGN TEMPERATURE
MINIMUM/ MAXIMUM ENTRY PRESSURE
MINIMUM/ MAXIMUM OFFTAKE PRESSURE
MINIMUM/ MAXIMUM ENTRY TEMPERATURE
MINIMUM/ MAXIMUM OFFTAKE TEMPERATURE
OPERATING PRESSURE
ΕΝ 1776
70 barg
-24 ºC / +60 ºC
35 barg / 66.4 barg
+5 ºC / +25 ºC
16.7 barg
OPERATING TEMPERATURE
MAXIMUM STATION CAPACITY
METER RUN NOMINAL CAPACITY
-
10000 Nm3/h
10000 Nm3/h
METERING EQUIPMENT
METER (EQUIPMENT) TYPE
Turbine meters
NUMBER OF INSTALLED METER RUNS
2
NUMBER OF INSTALLED CHROMATOGRAPHS
-
SUPPORTING EQUIPMENT TOTAL POSSIBLE ERROR
-
ENERGY UNCERTAINTY (FROM THE MANUFACTURER)
-
INSTALLATION DETAILS
METER CAPACITY
G 400
METER DIAMETER
150 mm
METER RUN DIAMETER
-
FLOW ALIGNMENT DEVICE DESIGN
-
Note:
Where 2 is indicated it means there is a backup metering device of the same type installed
Where 1+1 is indicated it means there is a backup metering device of a different type installed
Where 1+(1) is indicated it means that there is provision for backup metering device.
NATURAL GAS TRANSMISSION CONTRACT - APPENDIX C2
Page 79 / 80
Unofficial translation
TABLE 26
LAMIA TM5-R
INDIVIDUAL DESIGN SPECIFICATIONS
DESIGN CODE
DESIGN PRESSURE
DESIGN TEMPERATURE
MINIMUM/ MAXIMUM ENTRY PRESSURE
MINIMUM/ MAXIMUM OFFTAKE PRESSURE
MINIMUM/ MAXIMUM ENTRY TEMPERATURE
MINIMUM/ MAXIMUM OFFTAKE TEMPERATURE
OPERATING PRESSURE
ANSI B31.8
70 barg
-24 ºC / +80 ºC
41 barg / 66.4 barg
- / 37.7 barg
+7 ºC / -
OPERATING TEMPERATURE
MAXIMUM STATION CAPACITY
MAXIMUM RUN CAPACITY
-
90000 Nm3/h
METERING EQUIPMENT
METER (EQUIPMENT) TYPE
-
NUMBER OF INSTALLED METER RUNS
-
NUMBER OF INSTALLED CHROMATOGRAPHS
-
SUPPORTING EQUIPMENT TOTAL POSSIBLE ERROR
-
ENERGY UNCERTAINTY (FROM THE MANUFACTURER)
-
INSTALLATION DETAILS
METER CAPACITY
-
METER DIAMETER
-
METER RUN DIAMETER
-
FLOW ALIGNMENT DEVICE DESIGN
-
Note:
Where 2 is indicated it means there is a backup metering device of the same type installed
Where 1+1 is indicated it means there is a backup metering device of a different type installed
Where 1+(1) is indicated it means that there is provision for backup metering device.
NATURAL GAS TRANSMISSION CONTRACT - APPENDIX C2
Page 80 / 80