Study on Metal Deformation of Steel Tube with Cross-rolling Elongation and Related Roll Groove Design（Part Ⅰ）

Development of the steel tube cross-rolling/elongation technology is discussed briefly. And the influence on workpiece deformation by the rolling process characteristics and the process tools is discussed on the basis of the theoretic analysis concerning the metal deformation in Accu-roll mill deformation zone and related experimental research. Simulation analysis of the deformation zone and the analysis of the steel tube main deformation are carried out by means of relevant computer technology. Basic principle concerning roll groove design for cross-rolling/elongation process is put forward. Relevant experimental research demonstrates that the three rolling modes, i.e., diameter reduction, equal-diameter and diameter expansion can be obtained by means of proper roll groove design for Accu-roll pipe mill. Furthermore, the optimized roll groove has ensured Accu-roll mill to produce light-wall tube with D/S up to 41. The development of this technology will further improve the rolling of light-wall tube in terms of operation consistence and rolling speed.