LSAW Steel Pipe Manufacturing Process

LSAW steel pipe manufacturing process is simple, its production efficiency is high and at low cost, the development of straight seam welded pipe is rapid. Therefore, the straight welding is mostly used in smaller diameter of steel pipe. Today, as an excellent steel pipe manufacturer, Prime Steel Pipe will share the LSAW steel pipe manufacturing process in details for all of you.

LSAW steel pipe Manufacturing process:

1.Plate Analyzing：After the steel plate used to manufacture large diameter LSAW steel pipe entering into the production line, steel pipe manufacturer should carry out ultrasonic testing to the whole plate;

2.Edge Milling: Through the milling machine to carry out double-sided milling on both sides of the steel plate, to make it achieve the required plate width, board parallelism and groove shape;

3.Edge Crimping: Using the pre-bending machine to preliminary rolling, so that the board has the required curvature;

4.Molding: In the JCO forming machine At the first, steel pipe manufacturer should do stamping repeatedly for half of the pre-bent steel plate in the JCO forming machine, so that the steel plate is formed "J" shape, and then bending the other half of steel plate to form "C" shape, and finally formed the opening of the "O" shape;

5.Tack Welding: Making the LSAW steel pipe after forming joint colse and using the gas shielded welding (MAG) for continuous welding;

6.Automatic Internal Welding: Using vertical multi-wire submerged arc welding (up to four silk) to weld in the inside of the LSAW steel pipe;

7.Automatic External Welding: Using vertical multi-wire submerged arc welding to weld in the outside of LSAW steel pipe;

8.Automatic UT I: Using Automatic UT to 100% test the inside and outside wleded seam of LSAW steel pipe and the base material on both sides of weld seam;

9.X-Ray Testing I: Carrying out 100% X-ray industrial television inspection on the inside and outside the weld seam, and using image processing system to ensure the sensitivity of testing;

10.Mechanical Expanding: Expanding the full length of LSAW steel pipe to improve the dimensional accuracy of steel pipe and improve the distribution of stress in steel pipe;

11.Hydrostatic Testing: Testing the steel pipe after expanding one bu one in the hydraulic test machine to ensure that the steel pipe to meet the standard requirements of the test pressure, the machine has automatic recording and storage functions;

12.Chamfering: the pipe passed the inspection will be carried out pipe end processing qualified, to achieve the required pipe end groove size;

13.Automatic UTⅡ: Testing pipe one by one again by using root ultrasonic inspection to examine if there is defect on LSAW steel pipe after expanding and hydrostatic testing;

14.X-Ray TestingⅡ: Carrying out X-ray industrial television inspection on the pipe after expanding and hydrostatic testing, and take photos of the weld seam in the end;

15.Pipe End Magnetic Particle Testing(MPT): Carry out this inspection to find pipe end defects;

16.Corrosion protection and coating: Qualified steel pipe will carry out corrosion and coating according to user requirements.