TM 181
Serial ~ u m b e r l
Revised June 2008
056109
Department of Defence
MAW
Technical Regulation
The NAVY Way
Technical Directive
1
Serial numbers will be issued by DTR-N.
Whllst anyone can identify the need, only Authorised Engineering Organisations may sponsor TM 181s.
Expiry date is to be no more than 12 months fiom the Date of Issue.
4
All TM 181s are to contain a point of contact within the originating AEO.
All TM 181s are to be endorsed by an Engineering Authority of the appropriate level determined by the
category of t e c h c a l risk associated with the TM 181 and only after having assessed that risk. See ABR 6492
Volume 2 Section 5 Chapter 2 Annexes A&B for risk and engineering authority levels. Endorsement indicates
that technical risk has been assessed, and that the endorser is satisfied that any risk is being appropriately
managed.
TM 18 1s may only be released by an Executive Authority w i t h the originating AEO. Releasing officers are
to note that they are accepting, on behalf of the Commonwealth, the t e c h c a l risk associated with the TM 181.
2
Originating AEO:'
CME
Date of Issue:
0 1 Sep 09
EIC I CMC:
Various
Expiry
ate:^
02 Sep 10
Subject:
GENERAL REQUIREMENTS FOR THE CALIBRATION AND CHECKING OF SHIPBOARD GAUGES
METERS AND SENSORS
Applicability:
All platforms and AEOs
References:
A.
TM 181 016106 dated 10 May 06
B.
Commander, Naval Sea Systems Command Security Assistance Program office (PMS380) facsimile of
17 Apr 02.
C.
Australian Air Publication 7600.001-14(AM1) - Test and Measuring Equipment Calibration
Management and Handling Procedures Manual
D.
NAVSEA SISCAL Calibration Requirements List (CD) 0910-LP-102-4258
E.
ABR 5505, Volume 2 - RAN Marine Engineering Technical Instructions
F.
CSO(E) Minute 200811078919 FLEETIS1588578 dated 29 Jan 09.
INFORMATION
1.
This is a revision of Reference A with additional instruction on the management and maintenance of
pressure gauges as detailed in Reference F.
2.
The calibration procedures and periodicities, currently applied to shipboard gauges, meters and sensors
have evolved from the interpretation and application of various older planned maintenance documents and
calibration policies for test equipment. A review of these procedures, and advice fiom US sources at reference B,
has shown a general tendency to be over conservative and a hesitancy to take advantage of new calibration
technology. This often results in unnecessarily high costs and downtime whilst components are removed fiom
their systems. The purpose of this instruction is to provide:
3.
a.
guidance to engineering staff on the general requirements for the calibration of gauges, meters and
sensors that are used as part of ship's systems, and
b.
instructions for the incorporation of revised calibration requirements into planned maintenance
documentation.
Items Covered by this Directive. This Directive applies to measuring instruments and sensors that are
mounted into panels, bulkheads or other futed, shipboard systems.
4.
Test Equipment Managed and Calibrated by ADFCAL. This Directive does not apply to any of the
Test and Monitoring Systems (TAMS) that are used as test equipment and are managed by the ADF Calibration
(ADFCAL). This equipment includes automatic test systems, general purpose and special purpose test
equipment, weighing machines, weights and measures and is subject to separate calibration management policy
and procedures detailed at reference C.
-
5.
Differences Between Calibration and Maintenance Checks. This Directive refers to three basic
processes that may be used for c o n f i i n g the performance of measuring equipment: formal calibration,
performance checking and visual inspection. The differences between these are outlined in Annex A.
GENERAL CALIBRATION REQUIREMENTS
6.
Quantitative Applications. Calibration requirements are to be applied to only those meters and gauges
that are to be used for making quantitative measurements. For the purposes of this directive, a quantitative
application means using the instrument as a means of making accurate measurements or as a source for accurate
signals upon which decisions are based to accept, reject, adjust or control a device or system. By restricting
calibration to those instruments that only used in such qualitative applications, the calibration resources may be
used to maximum effect, and the costs and turnaround times minimised.
7.
Non-quantitative Applications. Instruments that are bekg used in non-quantitative applications only,
do not require periodic calibration and may be identified by a 'NO CALIBRATION REQUIRED' (NCR) label:
To assist in the identification of these items, guidelines on the NCR Criteria are listed in Annex B. Where these
items are being used as indicators they will still require function checks and visual inspections as part the planned
maintenance. In cases where an instrument has the capability for quantitative measurements but is not being used
in that application it may be identified by a 'CALIBRATION ON DEMAND' label until such a time as the
instrument is again required for quantitative applications.
CALIBRATION PROCEDURES
8.
Wherever practicable, all instruments are to be calibrated in-situ, ie on board the vessel and attached to
the parent equipment or system. The use of new technology in the form of portable Universal Calibration Kits,
designed for use in multiple pressure, temperature and electrical applications, is to be encouraged. Any
equipment used for the calibration of on board meters and sensors must be calibrated for those purposes and
traceable to a NATA certified organisation.
After calibration of an instrument, a 'Calibration Due Label' is to be affixed, showing the next
9.
calibration due date marked in permanent ink. Further details on labels are given in paras 23-24.
10.
As an interim measure when an instrument is considered suspect, it should be cross checked with other
on board test equipment. Any errors should be noted and corrections applied until calibration or repair facilities
are available.
If an instrument 'fails in-situ calibration' but is deemed economical for repair, it is to be returned to an
11.
approved shore based facility for repair and calibration. If it is deemed uneconomical for repair, it is to be
replaced.
SPECIFIC CALIBRATION REQUIREMENTS
The NAVSEA Calibration Requirements List
The USN has made available (at reference D) a CD-ROM Access database of a revised Calibration
12.
Requirements List (CRL) for all shipboard gauges, meters and sensors in the US fleet of FFGs. Although this list
does not refer to the RAN FFGs, it provides useful reference material summarising equipment types, locations,
measurement parameters and current calibration philosophies, procedures and intervals. The FFG SPO is to use
this CRL as a primary source document for establishing calibration requirements and to tailor the requirements to
adjust for differences in the RAN FFG hulls. The existing planned maintenance documentation detailing current
calibration requirements is to be reviewed and the revised requirements are to be incorporated therein. The
revised requirements are to be based on a combination of the US CRL and the following specific calibration
'
intervals.
Calibration Intervals.
13.
The calibration intervals for instruments listed below represent an extension fiom those previously used
in many RAN applications. The new intervals have been established fiom recent changes to US Navy
procedures, at references B and D, and supported by calibration hstory and defect data collected fiom Australian
ships. As a general requirement, on board gauges meters and sensors are to be calibrated at the following times or
periodicities:
a.
b.
c.
d.
e.
14.
at intervals not exceeding those listed below under the specific applications below,
prior to the commissioning of new instruments,
after any maintenance or repair that may influence the operation of the instruments,
when there are any suspicions of damage, overloading, mishandling or loss of accuracy, and
at reduced intervals where special circumstances, such as severe operating conditions or service
history andlor past calibration records, indicate a need for more frequent calibrations.
Pressure Gauges
All general purpose Analog pressure and Vacuum gauges,
Bourdon Tube gauges, Pressure Transducers,
Differential pressure gauges and Transducers
3 Years
Switches
12 Months
Notes:
All gauge fittings that have been removed, refitted or replaced since a system was last operated are
to be checked for correct fit, specification and material to ensure they are fit for purpose for use on
that system before it is set for work.
The faces of all gauges are to be kept clear of stickers and other attachments that may obscure
visibility of gauge markings - in accordance with section 5.1 of Australian Standard 1349-1986.
When replacing obsolete gauges and fittings on high pressure systems, the HRA should explicitly
consider the use of adapters where such is necessary.
The vacuum sides of compound pressure gauges with positive pressures greater than IOOpsig do not
require calibration. Since the vacuum range on these gauges represents only a small part of the total
range, it serves as an indication of vacuum only and has little quantitative value to the user.
Therefore, as long as the gauge is functional, only the pressure side requires calibration.
It has been shown that Bourdon tube gauges may be stored in clean, dry, vibration fiee
environments for up to three years without detrimental affects to the calibration. Accordingly, the
date the gauge is removed fiom such storage conditions can be considered as the 'DATE
CALIBRATED'. Gauges that have been stored for over three years should be recalibrated prior to
use since the effects of storage for periods of greater than three years is uncertain.
For pressure gauges used in oxygen, breathing and diving systems refer to specific planned
maintenance.
15.
Welding Equipment
Low Pressure Acetylene gauges
Other Gauges and regulators
12 Months
NCR
Notes:
Acetylene gauges. It is important that acetylene is not set at a pressure above 15 psig because of the
unstable characteristics of acetylene under pressure. Therefore, acetylene pressure gauges on the
low pressure side of the regulator require periodic calibration unless the regulator incorporates a
means to prevent overpressure. A calibration interval of 12 months should be used. It is not
necessary to calibrate at pressures greater than 15 psig.
Pressure gauges on the high pressure input side of regulators do not require calibration as they are
only used to indicate gas pressure in the cylinders.
Other types of gas pressure gauges used for welding, including oxygen pressure gauges used for
oxyacetylene welding, do not require calibration as they only serve to indicate that the regulator is
adjusted within the desired operating range. This is not a critical parameter as the operator must
make fiuther adjustments to the welding torch to get the desired flame.
16.
Diving Equipment. Calibration requirements for pressure gauges used in diving equipment shall be
referred to the Mine Warfare & Clearance Diving Systems Program Office.
17.
Conductivity Measurement Equipment. Shpboard installed salinity indicators and water
conductivity cells should be maintained in accordance with the relevant planned maintenance documentation.
18.
Pressure Relief Valves. Testing is to be conducted in accordance with the requirements set out in ABR
5225 Chapter 23.
Mechanical Gauges and Sensor Switches. Because of the large variation in applications and
19.
tolerances of this equipment, it is not feasible to set a generic calibration interval. Where the sensors are used in
safety, warning or system shutdown applications and could be subject to drift and change in set point value,
similar to that experienced by pressure and temperature measuring equipment, then they should be subject to
calibration at the same intervals. The calibrations should be done at the set points and tolerances required by the
system in which they are used.
20.
Temperature Measurement
All General purpose Thermocouples Thermometers
4 years
Special Applications including, Switches
Final Rinse Thermometers on dishwashers and
Magazine Thermometers
12 Months
Note:
Before any calibration work is conducted on temperature measuring instruments it is important to
ensure that an appropriate calibration method has been identified. Factors to consider include:
There are very few standard methods for calibration of temperature measuring equipment. Where
no suitable standard method can be found it may be necessary to develop a procedure. Such 'inhouse' methods are acceptable providing they have been verified for t e c h c a l validity.
Most standard methods for calibrating thermocouples apply to bare wire thermocouples with results
reported in millivolt output. Most thermocouples used in ship systems, however, are enclosed in
sheaths and connection heads. It is important that these parts are considered as part of the system
and the results reported in degrees.
Most thermocouples in ship systems are used in conjunction with a specific indicator and identified
as a digital thermometer or a digital temperature indicator. It is important that these items be
calibrated as a unit.
Panel and Switchboard Meters
21.
All General Purpose electrically operated panel
meters eg electric fuel gauges
3 years
Switchboard Voltage and Current Meters,
Frequency Meters, Wattmeters, Synchroscopes,
Phase Sequence Meters, Power Factor Meters prior
to commissioning and prior to generator load trials
Each Time
Thereafter
3 years
Notes:
Meters should be tested and calibrated in-situ wherever possible. If a meter is normally mounted in
a steel panel and must be removed for testinglcalibration, then it should be mounted in a steel test
panel of a comparable thickness.
Meters should be calibrated at full scale and at no less than two additional wdinal graduations
spread over the measuring range.
-
Flow Meters
22.
All General Purpose Flow Meters
(excluding those used in welding equipment)
3 years
Note:
It may not be practical to attempt to calibrate flow meters in-situ. Where flow meters are removed
for calibration they should be mounted in conditions to simulate the in-service application.
LABELS
23.
All gauges and instruments should be labelled to indicate the calibration status and, where appropriate,
the next calibration due date. The following standard labels are available:
Title
Calibrated (includes due date) - large
Calibrated (includes due date) - medium
Calibrated (includes due date) - small
Calibration Not Required - large
Calibration Not Required - small
Calibrate On Demand
Form
AA426
AA427
AA429
AA435
AA436
AA434
NSN
7540-66-130-8506
7540-66- 130-8507
7540-66-130-8509
7530-66-130-6969
7530-66-130-6970
7530-66-130-6968
24.
Labels fitted by external agencies are acceptable, provided they clearly indicate the calibration status.
Where labelling is impracticable or inappropriate, alternative means of recording should be used. Further detail
on the use of labels is provided at reference C.
RECORDS
25.
Every item calibrated must be covered by a calibration record or report which demonstrates traceability
to recognised physical standards. The results on a report must be reviewed to determine whether the item requires
corrections, whether the item has remained withm acceptable limits from the previous calibration, and whether
the results give confidence that the item will be suitable until the next scheduled calibration. If these conditions
cannot be met then action should be taken to re-establish confidence such as reducing the calibration interval or
replacing the item with a more suitable one.
Records and reports of calibrations and other planned maintenance checks and servicing are to be
26.
retained under data management arrangements between the ship and the relevant SPO. Any gauges, meters or
sensors that have been classified as Mandatory Maintenance Items are to be managed in accordance with ABR
6492 Volume 2 Section 4 Chapter 2 Para 2.33, and ABR 5230 Chapter 3 Para 3-76.
27
Thls Technical Directive does not take precedence over existing approved Planned Maintenance. It
provides benchmarks against which proposals to change PM can be assessed.
28.
course.
These instructions will be included the relevant chapters of ABR 5225 and ABR 5505 Vol 1 in due
Point of c o ~ t a c t : ~
29.
The CME point of contact is:
Mr. Graham McDonald
Telephone 02-9393 2979
Facsimile 02-C393 3468
graham.mcdonald@defence.gov.au
Annexes:
A.
B.
Differences between Calibration and other Maintenance Checks
No Calibration Required (NCR)Criteria
Drafter:
Signature:
&KL
Name: G. R. COOKE
Engineering ~uthority:'
d&
~ x e c u t i w ~ : : ~
d
&
&
A
Signature:
Signature:
Name: G. R. COOKE
Name: D. YORK
Department of Defence
TECHNICAL DIRECTIVE
056/09
ANNEX A to
TM 181 056 / 09
Dated OlSep 09
DIFFERENCES BETWEEN CALIBRATION AND OTHER MAINTENANCE CHECKS
1.
The three basic processes used for confirming the performance of measuring equipment are described
briefly below:
a.
Calibration. For the purpose of this Directive, calibration can be taken to mean the process of
comparing an in-service gauge or meter with a number of known, quantifiable values from a reference standard
to detect any errors in the in-service item. Where appropriate, any adjustments or corrections may be then
applied to the items to negate the effects those errors and to ensure that the item or system operates within the
specified tolerances. Items that are calibrated still need to be inspected and checked between calibrations to
confirm that they still function correctly.
b.
Checking. Checking should be part of a planned maintenance routine. Checks are intended to show
whether the system is consistently functioning correctly but they cannot substitute for calibration of the
measuring instrument. For example, in certain non-critical applications it may be acceptable to check a voltmeter
at a single point against a reference voltmeter to ensure that the working voltmeter is performing satisfactorily at
that one value where the measurement is made.
c.
Visual Inspection. Visual Inspections should also be part of the planned maintenance routines to
detect for damage, deterioration and simple functionality (eg to indicate onloff situation).
ANNEX B to
TM 181 0561 09
Dated 01 Sep 09
NO CALIBRATION REQUIRED (NCR) CRITERIA
1.
The NCR classification may be assigned to an instrument that meets any of the following criteria:
a.
It does not make measurements or provide known outputs. Examples include:
Non metered power supplies
Liquid sight glasses
b.
It is "fail-safe" in that failure to operate w i t h the specified performance limits will be
evident to the user. Examples include:
Frequency converters
Tank dip sticks
c.
It makes measurements or provides known outputs, which are monitored by another calibrated
device of sufficient accuracy during normal use. Examples include:
Remote firemain pressure gauges on static lines
Remote auxiliary exhaust pressure gauges
d.
It makes measurements or provides known outputs, which are dependent on known or
calibrated external references. Examples include:
Running time meters
Callipers and height gauges without scale
e.
It makes measurements which are required only to provide an indication of condition rather
than a numerical value. Examples include:
Pop-up differential pressure indicators
Lube oil purifier bowl pressure gauge
f.
It makes measurements or provides known outputs, but such measurements or outputs are not
used. Examples include:
Any gauge or instrument not used
Equipment Controls
Some equipment may contain graduated controls which may be set or adjusted to maintain the required
2.
system operating parameters. No calibration is required of those controls where their performance can be
verified by functional checks or other planned maintenance. Examples include:
Galley oven controls
Refi-igeratorlfreezer controls
Thermostats
Humidistats
Circuit breakers