LSAW Carbon Steel Pipe

Pipe Type:LSAW Steel Pipe,Longitudinally Submerged Arc Welding Pipe ,DSAW Steel Pipe,Welded Steel Pipe

Specification: Outside Diameter:355.6mm-2320mm 

                            Wall Thickness:5.0mm-60mm 

                            LENGTH:5.8m/6m/11.8m/12m/18m/32m 

Standard & Grade: ASTM A53: Gr.A, Gr.B;API 5L:Gr.A,Gr.B,X42,X46, X52,X56,X60,X65 PSL1 and PSL2; ASTM A572 Gr.50;ASTM A252 ;  API 5CT, ASTM 53, EN10217, DIN 2458. IS 3589, GB/T3091, GB/T9711,etc

End: Square Ends/Plain Ends (straight cut, saw cut, torch cut),Beveled/Threaded Ends 

Steel Grade: API 5L: GR B, X42, X46, X56, X60, X65, X70 ASTM A53: GR A, GR B, GR C

Surface: Black Painting/Oil Painting/Anti-Rust oil/Anti-Corrosive Coating 

Process: LSAW – UO(UOE)、RB(RBE)、JCO(JCOE,COE) DSAW -Double Submerged arc welded

Usage: Used for low pressure liquid delivery, such as water, gas, and oil.

The UOE mill features the most advanced technology and process, achieves high production efficiency, stable product quality and is equipped with complete inspection equipments. UOE mill adopts U & O forming, the formed pipes are welded inside through five internal welding stations with three wires, and welded outside through four external welding stations with three wires. In accordance with different requirements of the customers, the welded pipe can be expanded either by mechanical or hydrostatic expander to improve dimensional accuracy, and eliminate residual stress. 

JCOE LSAW steel pipe:

Specifications:

Outside Diameter：Φ406mm- 1626mm (16" - 64" )

Wall Thickness：6.0- 75mm (1/4" - 3" )

Quality Standards：API、DNV、ISO、DEP、EN、ASTM、DIN、BS、JIS、GB、CSA

Length：3-12.5m ( 10'- 41' )

Grades：API 5L A-X100, GB/T9711 L190-L690 

This is large diameter longitudinal submerged arc welded (SAWL) pipe production line in China. The mill adopts progressive bending process, featuring evenly distributed forming stress, high uniformity of dimension, infinite sizes variation&wide poduct range, and high flexibility, etc. 

Standard

Specification

Tolerance of Outside Diameter and Wall Thickness

Chemical Composition and Mechanical Properties

There are two main processes for LSAW pipe production: UOE and JCOE. Both processes utilize pre-welding, submerged arc welding, and expansion, but they differ in their weld preparation and application scenarios.

JCOE process
1. Forming sequence: The JCOE process is to form the steel plate in the order of J-C-O.
2. Welding and expanding: gas shielded welding is used for pre-welding after the joint of the steel pipe, and then submerged arc welding is used for internal and external final welding, and finally the segmented mechanical expanding process is used for cold expanding the whole pipe body.
3. Cost and adaptability: JCOE process cost is relatively low, process adaptability is strong, forming mold wear is small, and forming mold light.
4. Processing efficiency: Due to multiple molding, compared with the UOE process, the processing efficiency is low, but the mold is less and the equipment investment is low.
5. Dimensional accuracy: Due to the multi-step pressing of JCO, the dimensional accuracy of the steel pipe is lower than that of UOE, so UOE steel pipe is used in the ocean pipeline.

UOE process
1. Forming process: The UOE forming process first needs to process the edge of the steel plate bevel, flatten and bend the edge, and then press into U shape by the forming machine, and then bend into O shape.
2. Welding and expanding: After the joint of the steel pipe, the gas shielded welding is used for pre-welding, and then the submerged arc welding is used for internal and external final welding. Finally, the segmented mechanical expanding process is used for cold expanding of the whole pipe body.
3. Production characteristics: UOE molding technology is mature, reliable, good product quality, variety specifications, high output.
4. Equipment and investment: UOE equipment is larger than spiral welded pipe unit, and the investment cost is high.
5. Weld length: The weld length of the steel pipe under the same length is only half of the spiral weld, and the probability of defects in the weld is less.