A PROCESS FOR THE SHAPING OF A TUBE FROM A LONGITUDINALLY FED METAL BAND HAVING A THIN WALL-THICKNESS

摘要

Thin metal tape or strip is longitudinally folded into tubular form by means of a conical die with conical mandrel. The tape or strip is slightly bent temporarily just prior to folding so that the resulting convex side of the tape or strip becomes the inner tube surface. The tube is formed to have radial tabs which are trimmed and welded. The resulting tube is consistently impervious to fluid.