1. The manufacturing process of SSAW steel pipe determines that the residual stress of it is greater than that of LSAW steel pipe. LSAW steel pipe uses overall expansion process, the residual stress closes to zero, and the SSAW steel pipe can not do this.
2. The weld offset of SSAW steel pipe is mainly in range 1.1 ~ 1.2mm, the standard requires that the weld offset must be less than 10% of the wall thickness. For thin-walled SSAW steel pipe, the weld offset is difficult to meet the standard requirements, but the LSAW steel pipe have no this problem.
3. Compared with the LSAW steel pipe, the welding line of SSAW steel pipe is poor, the stresses concentration phenomenon is serious.
4. The heat affected zone of the SSAW steel pipe is larger than that of the LSAW steel pipe, and the heat affected zone is the key to the quality of the welded steel pipe.
5. The geometry accuracy of SSAW steel pipe is poor, which will bring some difficult to site operation, such as counterparts and welding.
6. For the same diameter, the thickness of the pipe SSAW steel pipe may reach is much smaller than the LSAW steel pipe, such as the thickness of LSAW steel pipe is generally 6 ~ 25mm, the maximum thickness of it can up to 45mm, while the wall thickness of SSAW steel pipe can only reach 18mm.
7. The welding line of LSAW steel pipe is shorter 60% than that of SSAW steel pipe, and there is less probability to appear welding line.
8. The base material of LSAW steel pipe is the single-controlled steel plate, that can be 100% non-destructive testing, and the base material of SSAW steel pipe is the hot-rolled steel coil, that can not be 100% non-destructive testing.
9. LSAW steel pipe adopts welding after molding process, there is conditions to check the quality of forming joints before welding, weld gap, groove, wrong side, etc. can be detected. And SSAW steel pipe adopts forming and welding at the same time process, Even workers found in the wrong side, slit and other defects in the welding process, it also is difficult to stop processing at any time, so we can see the welding quality of LSAW steel pipe is better than SSAW steel pipe.
Therefore, the process quality and comprehensive performance of LSAW steel pipe are better than those of SSAW steel pipe. For the LSAW steel pipe, according to the different molding process, it includes UOE, JCOE, HME, RBE and PFP five kinds of way to form tube, the former two are most common.
Prime Steel Pipe as a leading steel products manufacturer in China, our group offers a series of steel products including high-quality LSAW steel pipe and SSAW steel pipe. If you have any requirements of those, please contact us with email of call, we will try our best to serve you. More details about price list, please visit the hyperlink.