1.One set of machine can production round pipe,square &rectangular pipe and parts ... method,this method can make:better shape of angles for cross section,smaller semidiamer of inner arcis ,flatter ... brim,regular outlook. 2)Low load for the whole line, especially in the sizing part 3)2.4 ... roll cost,fast the bandroll turnover,shorten developing time for new lines. 3. Produce parts of abroch cold ...