Proposed is a method of longitudinal rolling of tubes in which wall thickness and diameter are reduced before the roll center line, and diameter expansion and wall thickness reduction are carried out after the roll center line. The mathematical model of the proposed method has been developed based on its idealization as a process of flat rolling of a strip in flat rolls, with a simultaneous forcing of a wedge into the strip body. Realization of the mathematical model, analysis of the calculation results and their interpretation in relation with longitudinal tube rolling process have made it possible to presume a possibility of increasing the shell wall thickness reduction while escaping axial shell feed breakdown with the use of the proposed method. Experimental testing of the proposed method in production conditions has proved a possibility for the increase in wall thickness reduction. It also corresponds to more than a 1.2 times increase in elongation using this method.
展开▼
