LSAW steel pipes manufacturing technology process

With the development of international economy, large diameter straight seam steel pipe with good pressure resisting capability, low resistance, low temperature resistant, corrosion resistant, easy installation and maintenance is becoming more and more popular in oil and natural gas, steel structure project and pulp conveying.

LSAW Steel Pipes

Then do you know the LSAW steel pipes manufacturing technology process? Today I will enjoy my experience to you.

★ Coil inspection: The steel plates used to produce large diameter LSAW pipes enter into production line, first do ultrasonic inspection for full plate;
★ Edge milling: Through edge milling machine, the two edges of steel plates is double-side milling in order to make it meet the requirements of plate width, plate parallelism and groove shape;
★ Pre-bending: Make use of pre-bending machine do plate edge pre-bending to make it conform to the requirements of the curvature;
★ Forming: On the JCO forming machine, first put half of steel plate of pre-bending punching through many steps to form “J”, then another half of steel plates do the same bending to pressure into ”C”, eventually forming the opening “O”;
★ Pre-welding: Make the forming straight seam welded steel pipe join and use the gas shielded welding (MAG) for continuous welding;
★ Inner welding: Do inner welding inside straight seam welded steel pipe adopting tandem sequence submerged arc welding (up to four);
★ Welding: Do welding outside LSAW (Longitudinal submerged-arc welded pipe) using tandem sequence submerged arc welding;
★ Ultrasonic inspection: 100% ultrasonic check on straight seam welded steel pipe about inside and outside welding seam and both sides of welding seam;
★ X-ray check: 100% X-ray industrial check on inside and outside welding seam, using image processing system to ensure sensitivity of detection;
★ Hole enlargement: Do hole enlargement for the whole length of LSAW pipes in order to improve the size precision of tube and the distribution of stress in LSAW steel tube;
★ Hydrostatic test: Do hydrostatic test for hole enlargement steel tube to ensure LSAW pipes meet the standard requirements;
★ Chamfering: Do pipe end processing for the qualified LSAW steel pipe to meet the requirements of tube end groove size;
★ Pipe end magnetic powder inspection: This inspection is to find the pipe defect;
★ Corrosion protection and coating: According to customers’ requirements do corrosion protection and coating for qualified LSAW steel pipes.

AGICO is one of the most popular LSAW pipe manufacturers in China, we have professional manufacturing process line to meet different requirements for our customers from all over the world.