SPECIFICATION NUMBER: TI/SPC/OHE/EXTHRMBOND/010(04/10)
GOVERNMENT OF INDIA
MINISTRY OF RAILWAYS
TECHNICAL SPECIFICATION
FOR
Exothermic Welding connection for
Bonding, Earthing/Grounding
ISSUED BY
TRACTION INSTALLATION DIRECTORATE
RESEARCH DESIGN AND STANDARDS ORGANISATION
MANAK NAGAR, LUCKNOW 226 011
(INDIA)
(For official use only)
Page 2 of 17 pages
Effective from 01.04.10
Spec No. TI/SPC/OHE/EXOTHRMBOND/0100(4/10)
SPECIFICATION NUMBER:
TI/SPC/OHE/EXOTHERMBOND/0100(4/10)
FOR
EXOTHERMIC WELDING CONNECTION FOR BONDING &
GROUNDING
Amendment
Date of Amendment
Total pages
including drawings
Amendment/Revision
0
NA
17
First issue
CHECKED BY
-Sd/8.4.10
DTI-MRVC
APPROVED BY
-Sd/8.4.10
ED/TI-Co.
SIGNATURE
DATE
DESIGNATION
PREPARED
-Sd/8.4.10
ADE/OHE-D
COPY NUMBER
ISSUED BY ---------------------- SIGNATURE -------------------- DATE ------------------ISSUED TO
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
NOTE:
This specification is property of RDSO. No reproduction shall be done
without permission from DG (TI), RDSO. This specification is not for
general use.
Page 2 of 17 pages
Effective from 01.04.10
Spec No. TI/SPC/OHE/EXOTHRMBOND/0100(4/10)
SPECIFICATION NUMBER:
TI/SPC/OHE/EXOTHERMBOND/0100(4/10)
INDEX ITEM NO.
1
2
3
4
5
6
7
8
9
10
11
12
13
HEADING
Forward
Scope
General and other requirement
Welding Material
Welding Tool
Marking
Packing
Acceptance Criterion
Training/Instruction Manual
Information to be supplied by the purchaser
Appendix-I(Sheet 1 to 2)
Appendix-II(Sheet 1 to 3)
Appendix-III(Sheet 1 to 3)
PAGE
3
3
3
5
5
7
8
8
9
9
10 to 11
12 to 14
15 to 17
Page 3 of 17 pages
Effective from 01.04.10
Spec No. TI/SPC/OHE/EXOTHRMBOND/0100(4/10)
Specification No. TI/SPC/OHE/EXOTHRMBOND/0100 (04/10)
For
Exothermic Welding Connection for Bonding & Grounding
1.0
Forward
This specification basically covers the technical provision & requirements and does
not include all other necessary provisions for the contract.
2.0
Scope
2.1
This specification covers the requirements and acceptance criterion for weld
material, welding tool and tool kit, bonds/track bond wires for making permanent
electrical bond connection between two conductors.
2.2
The intent of this specification is to ensure the production of properly formulated
and tested weld material for making traction bond connection to/between the
traction rails/track and with OHE structure for electrical continuity with adequate
bonding strength. The prime concern must be focussed on the necessary design and
quality requirements to achieve adequately strong weld connection, which shall
eliminate in service connection failure under severe climatic and adverse field
conditions.
2.3
These weld materials including tool kit shall be useful in following railway
application on 25kV electric traction system.
(a)
(b)
(c)
(d)
(e)
(f)
(g)
(h)
Traction bond connection to rail & OHE structures route.
Traction rail continuity connection.
Earthing connections like at TSS, SP/SSPs, SCADA/RTU and other
important electrical installations.
Bus bar connections etc.
Copper to copper, copper to steel connection.
Important bonds which are not disturbed during track relaying.
Sections where 90UTS rails have been provided.
Theft prone areas.
3.0
General and other requirements
3.1
Manufacturers should have a good quality assurance system to guarantee the
product e.g. ISO 9001 – 2000 assessed by authorised agency.
Page 4 of 17 pages
3.2
3.3
3.4
Effective from 01.04.10
Spec No. TI/SPC/OHE/EXOTHRMBOND/0100(4/10)
Manufacturers should provide sales reference list that shows type, delivery,
customer and address of customers, details of catalogue and type test reports &
approvals of the product.
Manufacturer should submit approval & test reports, both internal and external
from authorised/reputed test houses as per National/ International Standard.
The welded connection should pass the following parameters if tested as per
IEEE-837:
•
•
•
•
•
•
•
Mechanical Pullout,
Electromagnetic force,
Resistance,
Freeze-thaw cycling,
Salt Spray test,
Corrosion-acid test and
Fault current test.
3.5
Welding material along with tool kit shall be capable of providing a permanent
bonding connection involving copper or aluminium or steel as specified by the
purchaser. The final bond shall be achieved in such a way that homogeneous
molecular bonding of two involved metals takes place perfectly.
3.6
Exothermic Welding process should be: A steady burn, No pops, No drastic colour
changes (white hot colour during burn, turns orange as the reaction stops and the
molten metal grows orange).
3.7
Welding connections should be without voids or pinhole, and no porosity should
be detected. The process shall be consistent and continuous.
3.8
It shall be permanent, solid metal, maintenance free connection and shall not be
affected by high current surge.
3.9
It shall not loosen or corrode at the point of weld. There shall be no additional
contact surface or mechanical pressures involved.
3.10
It shall be vibration proof and corrosion free electrical connection.
3.11
It shall not brittle with age and shall be able to sustain physical impacts, which
may be experienced under the field conditions.
3.12
Electrical resistance and other properties shall not deteriorate with ageing and
under severe Indian climatic conditions.
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Spec No. TI/SPC/OHE/EXOTHRMBOND/0100(4/10)
3.13
It shall have a current carrying capacity equal to or greater than that of the
conductors.
3.14
Life of the joints itself shall not be less than 10 years irrespective of life of
conductors, equi-potential earth bus bars or Ground Rods used.
4.
Welding Material
4.1
The weld material shall be designed for two specific types of jointing application
as mentioned above (a) rail welding application and (b) earthing & bonding
application.
4.2
It shall not contain phosphorous or any caustic, toxic or explosive substance. For
rail welding application, the welding material should not contained tin besides the
above cited elements. Its components shall not be volatile or sensitive to shock,
nor shall they be capable of spontaneous ignition or ignition by friction.
4.3
The reaction of the weld material shall be completed within 10 seconds and on
completion of jointing & bonding process no un-reacted material shall remain. The
resulting weld nugget shall be free of dissolved gases or low boiling point
elements, e.g., small voids or blisters on the surface.
4.4
Weld material shall provide a final bond with minimum tensile strengths of 40,000
psi tested using ASTM ES-94a (Test Methods for Tension Testing of Metallic
Material). As a guideline, 3 samples of ½” diameter test specimen & 5½” long of
weld material shall be cast in the form of bars using 250 gms of weld metal
powder and tested as cast for tensile strength or as per any other standards
accepted by the purchaser on any tensile testing machine of adequate capacity.
4.5
The weld material for traction bond and stud welding for rail application shall be
free from tin. As presence of metallic tin allows for wetting of rail surface and
provides for unnecessary penetration that can lead to metallurgical damage to the
rail.
4.6
The weld material for earthing & bonding application shall be UL listed and shall
be tested as provision of IEEE-837 by NABL/ILAC Member labs. The
manufacturer should have latest UL certification for their facilities and it should be
regularly extended after the expiry of the certification to ensure genuineness.
5.
Welding Tool
5.1
It shall be suitable for bonding as per the sizes specified in Appendix-I to III for
bonding Equi-potential Earth Bus Bars (EEBB) to ground rod, protective conductor
etc.
Page 6 of 17 pages
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Spec No. TI/SPC/OHE/EXOTHRMBOND/0100(4/10)
5.2
The tools shall be of lightweight and whole kit containing bonding material; weld
materials and tools shall be easily portable by one person from one spot to another.
5.3
It shall be possible to remove it immediately after jointing or whenever required.
5.4
In-built protection shall be available against any flash generation during weld
process, which is injurious to user.
5.5
Tools required for high temperature working shall be of graphite or suitable
material so as to be capable of working at temperatures sufficiently higher than the
temperature conditions achieved during jointing.
5.6
Any ignition tool included in the tool kit shall be portable and easy to operate.
Ignition time shall be very quick and shall work efficiently even under damped
weather conditions.
5.7
For quality and safety, moulds, bonds, weld material and other tools shall be
supplied as one unit unless otherwise mentioned by the purchaser.
5.8
For integrity and safety of the connection, the weld metal, moulds and clamps
should be of the same manufacturer.
5.9
Whole weld kit shall be light, portable, self contained, simple in working and shall
require very little time and skill to make perfect connection every time.
5.10
Tool kit shall give consistent quality bond for at least 100 joints for non-tensioned
joints.
5.11
Welding connection shall be completed within 10 second and in such a way that
amount of heat (in calories or BTU) required for final connection causes no damage
to conductors and its insulation and to metal surfaces.
5.12
Power operated tools, if any, for carrying out weld work shall have the provisions
for its working on 110/230V a.c. and portable battery.
5.13
Suitable means and guidance shall be provided to prevent equipment failures
connected through rails due to flow of electric current during weld process.
5.14
Complete jointing process including preparatory work shall not take more than 2 to
3 minutes per bond under normal working conditions, to avoid requirement of
traffic line blocks.
Page 7 of 17 pages
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Spec No. TI/SPC/OHE/EXOTHRMBOND/0100(4/10)
5.15
If any melting of metal is involved in the jointing process, it shall quickly solidify
so that system is immediately available for charging.
5.16
Once ignition is started it shall not result in imperfect bond/joint.
5.17
Welding kit shall comprise of weld material, bonding material & tool kit. It shall be
supplied in sufficiently strong carry-bag for easy transportation by the Maintenance
people.
5.18
Weld material shall not contain hazardous ingredients sufficient to constitute a
hazard & weld process shall not result in any surface irregularities.
5.19
Welding material shall have a minimum shelf life of five years, when stored in a
reasonable storage condition, so that material can be used without any testing
within this period for optimum results.
5.20
Detailed training manual including working instructions for the user for achieving
best results shall be supplied along with each tool kit. Necessary instructions for
protection of workers shall be incorporated if process is harmful to human beings.
Whenever required, necessary guidance shall be given by manufacturer (or)
manufacturer’s trained representative to user at site.
5.21
In case of any mishandling or accidental situation, details of suggested first-aid
measures shall be given.
5.
MARKING
6.1
Each package/ box of welding material/bonds shall be properly marked for easy
identification and shall be stamped with the lot number.
6.2
Carton shall have part number printed, contents, size and weight shall also be
marked.
6.3
To maintain traceability, batch and/or lot control identification shall be marked on
packages prior to despatch of consignment.
6.4
Month and year of manufacture shall be marked on the container.
6.5
For materials having a limited shelf life, a clear expiry date shall be marked before
which material is to be consumed for best results.
6.6
All the sizes, weight and other dimensions of packed items shall be marked with an
accuracy of ±5%. The marking shall be distinctively in indelible printing-cumindented/embossed form.
Page 8 of 17 pages
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Spec No. TI/SPC/OHE/EXOTHRMBOND/0100(4/10)
7.
PACKING
7.1
The containers for weld material shall be moisture resistant and shall be packaged
to prevent damage, separation or spillage during shipping.
7.2
The weld material including starting powder should packed in the waterproof
transparent plastic. The starting powder should put on the bottom of the tube.
7.3
The weld material shall be pre-measured for specific applications suitably marked
and packaged together in a non-absorbing container.
7.4
It shall be packed in such a way that it shall not loosen during transportation and
normal handling.
7.5
Container and caps shall be marked with unit size and show item number,
manufacturer, and manufacturing date.
7.6
All the contents like weld material, bonds, tools etc. shall be packed individually
and then repacked in a bigger single pack.
8.
ACCEPTANCE CRITERION
Following shall be provided by manufacturer for evaluating the product before it is
considered suitable for its applications on Indian Railways -
8.1
Remarks/compliance shall be given for all provisions of this specification.
8.2
Details of welding process, properties and chemical composition of weld material,
its energy content shall be provided.
8.3
Standards followed in manufacturing and testing of products including weld tools.
8.4
Details of analysis carried out by manufacturer, as a routine test on raw materials,
final product and Quality Assurance Testing shall be made available for evaluation
or as and when asked by the purchaser.
8.5
Laboratory test results including field observations for verification and validation
of all results of Quality Assurance Testing & Engineering specification.
8.6
UL listing certificate for the weld connection along with the test report as per the
provisions of IEEE-837 by NABL/ILAC Member for welding material required for
earthing and bonding other than track.
Page 9 of 17 pages
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Spec No. TI/SPC/OHE/EXOTHRMBOND/0100(4/10)
8.7
Documents to ensure nil effect of weld process on EEBB or ground rod surface or
on rail surfaces as the case may be.
8.8
Details of substances hazardous to health of workers and precautions to be taken
during process.
8.9
Performance feedback and acceptability of same product on Indian Railways and/or
other Railway system abroad/power transmission and distribution system etc.
Product must have been in use for similar applications for at least 2-3 years.
8.10
Manufacturer shall arrange for any other test and/or documents considered
necessary by the purchaser to establish quality and performance of the product.
8.11
Two copies of training/instruction manual.
8.12
Guarantee for supply of spares and consumables for 10 years.
8.13
Suppliers/manufacturers with a new product complying the requirements of this
specification except Clause-8.8 above may be considered for educational/
developmental orders only.
9.0
Training /Instruction Manual
The supplier shall impart adequate practical training to field staff to operate the
exothermic welding kit at site. The training shall cover the procedures & safety
measures to be adopted by the Railway staff while performing the welding process.
Supplier shall also supply two copies of Training/Instruction Manual along with
each exothermic welding kit.
10.0
INFORMATION TO BE SUPPLIED BY THE PURCHASER
10.1
Type of applications.
10.2
Quantity (item-wise) for bonds, weld material (for different applications) and tools
required.
10.3
Sizes and length of bonds, Equi-potential earth bus bar (EEBB), protective
conductors & ground rods and dia of all the cross sections to be bonded and all
relevant sizes to be used for jointing surface.
10.4
Inspecting Agency for acceptance of material.
***
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Spec No. TI/SPC/OHE/EXOTHRMBOND/0100(4/10)
Appendix-I (Sheet-1)
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Appendix-I (Sheet-2)
Spec No. TI/SPC/OHE/EXOTHRMBOND/0100(4/10)
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Appendix-II (Sheet-1)
Spec No. TI/SPC/OHE/EXOTHRMBOND/0100(4/10)
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Appendix-II (Sheet-2)
Spec No. TI/SPC/OHE/EXOTHRMBOND/0100(4/10)
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Appendix-II (Sheet-3)
Spec No. TI/SPC/OHE/EXOTHRMBOND/0100(4/10)
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Spec No. TI/SPC/OHE/EXOTHRMBOND/0100(4/10)
Appendix-III (Sheet-1)
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Spec No. TI/SPC/OHE/EXOTHRMBOND/0100(4/10)
Appendix-III (Sheet-2)
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Spec No. TI/SPC/OHE/EXOTHRMBOND/0100(4/10)
Appendix-III (Sheet-3)