Description of the main production process of LSAW steel pipe

LSAW steel pipe

Plate Ultrasonic Inspection

Each plate is first full-plate ultrasonic inspected after entering the process

Plate Edge Milling

The Plate edges are milled by Edge Milling Machine to obtain the required width, parallelism and bevel angles;

Plate Edge Crimping

The two edges of the plate are crimped at the Crimping Machine to get the required radius;

LSAW steel pipe

Forming

The first half of the plate is fed step by step into the Pipe Forming Press to form the plate into a” J “shape. Then another half of the plate is pressed step by step to form the plate into” C “shape. The last stroke is to press the plate into an open “O” shape;

Continuous Tack Welding

The two edges of the open seam pipe should be brought together by tack welding machine then welded by tack welder using metal active-gas arc welding (MAG) process;

Inside Welding

the pipe is welded from inside of the pipe by multipass tandem submerged-arc welding (max. four wires)

Outside Welding

The pipe is welded from outside of the pipe by multipass tandem submerged-arc welding;

Ultrasonic Testing I

The welded area on both sides of the weld are 100% tested by automatic ultrasonic tester .