Single Radius Forming Process of Welded Steel Pipe

Single Radius Forming Process of welded steel pipe

This is a kind of common forming process, our country most small and medium-sized tube pass using the process of the unit. As shown in figure 4, each of groove for deformation are composed of a radius, from 6 ~ 7 horizontal roll forming process with the appropriate auxiliary deformation vertical roll in, some is flat vertical and white, some three flat roller is arranged in the last, the second three vertical roll, have distinguishing feature each, this technology has the advantage of roll processing is convenient, coarse forming part of the roll have certain common sex; Defect is inadequate deformation of steel strip edges, formed just after the end, into a welded pipe welding/peach shape 0, can guarantee welding quality of steel pipe. Steel strip after 2 ~ 3 layers forming the pass system, into the empty curved edge of the stage, as shown in figure 5, the curvature of edge is hard to change, even if again after a few mouths groove processing could not make edge to achieve the requirement of the squeezing roller. Although this forming process, the common rough shaping pass to a certain extent, but when changing the thickness of the steel tube, is not conducive to the edge shape. Coarse molding groove roller as consisting of a concentric circular arc, and the difference is steel pipe wall thickness, when changing the thickness of the steel tube is not concentric circles, thickness increases, the roller is raised, the middle section changes with different on both sides, on both sides of the roll gap increase is small, excessive pressure of edge, edge wave may be produced and affect the welding quality. When thinner welded pipe production, top roller pressure, on both sides of the roll gap reduction is also small, edge is not fully processed, have just end, also affect the welding quality. And rough forming roll the roller due to roll speed difference, slitting steel strip edge edge factors such as easy to wear and also can produce enough just side affect welding quality.

In the production of large diameter welded pipe, the thick forming roll diameter difference between middle and edge is big, roll the speed difference of the conference on steel pipe surface scratch, affect the quality of welded pipe's surface.