LSAW Welding Pipe Features and Manufacturing Processes

LSAW welding pipe manufactured by IBC (Tianjin) Industrial Co.,Ltd are in high quality with competitive price. The welded pipes are produced by three types of welding processes. Electric Resistance Welding also called ERW, Fusion Welding short for EFW and Double Submerged Arc Welding (DSAW or LSAW or SSAW). In the ERW and EFW manufacturing process welded pipes formed by hot or cold rolling plate and welding the seam. And then let’s learn what is the LSAW welding pipe.

What is LSAW Welding pipe?

LSAW welding pipe also know as Longitudinal submerge arc welding. Also called SAWL or DSAW. This carbon steel pipe is a type of SAW pipe. LSAW pipe made of steel plates that were hot rolled by JCOE or UOE forming technology. JCOE technology represents the shaping and forming processes involved during manufacturing. As well as the inner and outer welding and cold expansion carried out after welding.

When compared to UOE LSAW steel pipes, LSAW pipe manufacturers in China can produce more sizes as thus. OD 406.4 mm – 1524 mm. Thickness 6.35 mm – 100 mm. Pipe length from 1.5 m to 18 m with the LSAW pipe having superiority. IBC (Tianjin) Industrial Co.,Ltd offers LSAW steel pipe with high quality and competitive prices.

Features of LSAW Welding pipe


  • Large diameter steel pipes
  • Thick walls
  • High-Pressure resistance
  • Low-temperature resistance
LSAW welding pipes

Tests of LSAW Welding Pipe

  • -Chemical Component Analysis
  • -Mechanical Properties – Elongation, Yield Strength, Ultimate Tensile Strength
  • -Technical Properties – DWT Test, Impact Test, Blow Test, Flattening Test
  • -X-ray Test
  • -Exterior Size Inspection
  • -Hydrostatic Test
  • -UT Test

LSAW Pipe Manufacturing Process

Longitudinal Submerged Arc Welding is a specific welding technique used in pipe production where the finished product requires a particularly high wall thickness due to high internal or external pressures. The LSAW steel pipe manufacturing process explained in the steps below:

LSAW welding pipe
LSAW welding pipe Manufacturing Process
LSAW welding pipe Charming

Firstly, after LSAW pipe mill purchased raw material from plate factory. We do Plate Probe. This used for manufacturing the large diameter LSAW joints right after it enters the production line which is the initial full-board ultrasonic testing.

Secondly, after plate probe, Milling is second step. The machine used for milling does this operation through two-edged milling plate to meet the requirements of the plate width and the sides parallel to the shape and degree.

Thirdly, Pre-curved side. This side is achieved by using a pre-bending machine on the pre-bending plate edge. The plate edge needs to meet curvature requirement.

Fourthly, Forming. After the pre-bending step, in the first half of the JCO molding machine, after stamped steel, it pressed into a “J” shape while the on the other half of the same steel plate it bent and pressed into a “C” shape, then the final opening forms an “O” shape.

Fifthly, Pre-welding. This is to make a welded pipe steel a straight seam after it has been formed and then use gas welding seam (MAG) for continuous welding.

Then, inside welding and outside welding. This is done with a tandem multi-wire submerged arc welding (about four wire) on the inner part of the straight seam welded steel pipe. Outside weld the tandem multi-wire submerged arc welding on the outer part of the LSAW steel pipe welding.

Then testing step is Ultrasonic Testing. Outside and inside of the straight seam welded steel pipe and both sides of the base material welded with 100% inspection. X-ray inspection. X-ray industrial TV inspection carried out on the inside and outside. Using image processing system to make sure there is detection sensitivity. Hydraulic test carried out on the hydraulic test machine for steel after expanding by-root test. For ensuring the steel pipe meets the standard requirements with the machine having an automatic recording and storage capabilities.

Moreover, Expansion. This is for accomplishing submerged arc welding and straight seam steel pipe length hole diameter so as to improve the steel tube’s size precision. And improve the distribution of stress in the steel tube.

Finally, Chamfering. This involves the inspection carried out on the steel pipe at the end of the whole process. And then finishing step, coating or without coating and put on the iron ring to protect the pipe end. Package or not according to customers’ requirements.

Application of Pipeline LSAW Welded Pipe

The basic metal and welding metal have been tested according to the specification of the pipe API SPEC 5L, DIN, EN, ASTM, GOST standard and other standards. Also, LSAW pipe can weld with flanges, lifting eyes and other parts depending on clients’ requirements. LSAW pipe used for conveying fluids like oil, gas and water transportation. As well as used for seashore projects and ground constructions. These products manufactured in China. And exported to other countries like United States of America, Canada, India, Pakistan, Africa, etc.

application of LSAW welding pipe

IBC Metal Group experienced in manufacturing Pipeline for projects all over the world. For more information, please contact with us.