In the rapid development of steel at the same time, some of the counterfeit steel products on the market also appeared, then how to correctly and accurately identify the quality of steel is good or bad? 1, the appearance of counterfeit steel pipes often appear papules. The surface .........
2017-7
In the submerged arc welding zone, defects such as blowhole, hot crack and undercut are easy to occur. 1, foam. The main reason is the bubble occurred in the weld hydrogen remains hidden in the formation of air bubbles in the weld metal, so the elimination of defects is the f.........
2017-7
In the process of forming the spiral welded pipe, the plate deformation is uniform, the residual stress is small, and the surface does not produce scratches. The processing of spiral steel pipe diameter and greater flexibility, the size range of wall thickness, especially in the high-end .........
2017-7