Double Submerged Arc Weld
Welding process wherein the required are usually accomplish in separate processes, hence the word ???double???. These separate welds consume a portion of the other, resulting in a single high quality weld nugget. DSAW pipe is normally produced in sizes from 24??? through 80??? OD. Pyramid rolls process the cylinder is formed between three rolls arranged in a pyramidal fashion.
DSAW pipe may or not may be cold expanded. Cold expansion is process where the pipe is an expanded dimension. In the process, a gain of yield strength results. Expansion is most often utilized in a U-O-E mill due to the need to recover the yield strength lost during the forming of in the ???0??? press. DSAW pipe is normally produced in double random lengths with square ends or beveled for welding. Fabrication services are available to produce lengths longer than the standard DRL (double random lengths 11-12 Mtrs). A wide range of external coating and internal linings are available with DSAW pipe.
Longitudinal Seam Submerged Arc Welded Pipes (LSAW)
With an installed capacity of 325,000 TPA in the facility, produces high quality pipes adhering to international standards. The manufacturing facilities incorporate the hybrid JCO&E technology, which provides flexibility in terms of thickness and grade, to produce pipes in a diameter range of 12 to 80, 6 mm to 65 mm thickness and grade up to API 5L X- 80. The facility also possesses latest inspection to meet specific requirements on execution, strength, tolerance, length etc.
Salient Features of LSAW Facility
Salient Features of HSAW Mill
The manufacturing process used for HSAW pipes consists of two steps:
API 5L PIPES
API 5L Line Pipe Testing Requirements
Lists hydrostatic inspection test pressures for all sizes and graded covered by the specification.
Seamless (all sizes) 5 seconds
Welded (NPS 18 and smaller) 5 seconds
(NPS 20 and larger) 10 seconds
ERW longitudinal and transverse
|NPS||On One Length from each Lot|
|5 and smaller||400 or less|
|6 through 12||200 or less|
|14 and larger||100 or less|
?????????????????????? Seamless: 0.158-0.983 wall, tolerance = -12.5% / + 15%
?? ?? ?? ?? ?? ?? ?? ?? ?? ??> = 0.6984 wall, tolerance = -0.120 / +0.146 or – / + 10 % of whichever is greater (except if OD is > = 14 & wall is > = .984 then tolerance is -10 / +15%)
?? ?? ?? ?? ?? ?? ??HFW: < = 0.167 wall, tolerance = – / + .020
= 0.198-0.590 wall, tolerance = – / + .10.0%
= 0.591 wall, tolerance = – / + .060
Weights per foot
For Single Lengths Special Plain End and Grade A25 Not more than plus 10 % minus 5 %
For Single Lengths Other Pipe Not more than plus 10 % minus 3.5 %
For Carload lots not more than minus 1.75%
Note: NPS 2 OD and smaller may be weighed individually or in convenient lots; larger sized by length