Volume-II - GAIL
Volume-II - GAIL
Volume-II - GAIL
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6.2.5<br />
The minimum elongation of base metal shall be determined in accordance with the formula<br />
given in foot note (a) of Table-3B and shall comply with the minimum values of API Spec. 5L<br />
Appendix D. However elongation in no case shall be less than 20%. API Spec. 5L Appendix D<br />
stands modified accordingly.<br />
The ultimate tensile strength (UTS) of the weld shall be equal to or better than the specified<br />
minimum tensile strength of the base metal.<br />
Fracture Toughness Tests<br />
6.2.5.2 Charpy Impact Tests for PSL 2<br />
6.2.5.2 e<br />
(New)<br />
For the pipes of all grades and wall thickness , Charpy V- notch impact test in accordance with<br />
SR5 (Appendix – F) shall be performed.<br />
Additionally, for SAW pipes of all sizes and specified wall thickness, additional fracture<br />
toughness requirements as per supplementary Requirements SR 19 of API Spec. 5L and as<br />
modified in this specification shall be applicable for body, weld and heat affected zone (HAZ).<br />
6.2.5.3 Supplementary Fracture Toughness Tests<br />
6.2.6<br />
6.2.6.1<br />
(New)<br />
For EW Pipes<br />
For pipes sizes 16” and larger, Drop Weight Tear Test (DWTT) in accordance with<br />
Supplementary Requirements SR 6 of API Spec. 5L and as modified in this specification shall<br />
also be performed.<br />
For SAW Pipes<br />
Wherever line pipes are specified for Hydrocarbon service in gaseous phase and High Vapour<br />
Pressure (HVP) service in Purchase Order, Drop Weight Tear Test (DWTT) in accordance with<br />
Supplementary Requirements SR 6 of API Spec. 5L and as modified in this specification shall<br />
be also performed for all pipe size, grade and wall thickness.<br />
Metallographic Examination<br />
For EW Pipes<br />
A test specimen for Metallographic & hardness examination shall be taken transverse to the<br />
longitudinal weld, from one finished pipe from each lot of 50 pipes per heat or at least once<br />
per operating shift (12 hours maximum) which ever is occurring more frequently and<br />
whenever changes in grade, diameter or wall thickness are made or whenever significant<br />
excursions from operating heat treatment conditions are encountered. The specimen shall be<br />
suitably ground, polished and etched to reveal the microstructure. The specimen shall be<br />
visually examined using adequate magnification to provide evidence that heat treatment of<br />
weld zone is adequate and there is no untempered martensite left. In case defects are<br />
observed, it will become a cause of re-evaluation of welding parameters and heat treatment<br />
as deemed necessary by Purchaser's Representative.<br />
For SAW Pipes<br />
A test specimen for Metallographic & hardness examination shall be taken transverse to the<br />
longitudinal weld, from one finished pipe from each lot of 50 pipes per heat or at least once<br />
per operating shift (12 hours maximum) which ever is occurring more frequently and<br />
whenever changes in grade, diameter or wall thickness are made or whenever significant<br />
excursions from operating heat treatment conditions are encountered. The specimen<br />
<strong>GAIL</strong> (INDIA) LIMITED CARBON STEEL LINE PIPES <strong>GAIL</strong>-TS-LINEPIPE-CS<br />
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