Papers by Author: Kang Sheng Zhang

Abstract: Cross wedge rolling valve roughcast is charactered by minor diameter, long stretching and heavy section shrinkage; however, it is hard to select a set of suitable machining process parameter and prone to rolling internal defect. In order to research this problem, a whole forming process of valve roughcast by single cross wedge rolling is simulated with finite element simulation software DEFORM-3D 6.0, which focuses on the stress and strain of the center point of rolled piece under different forming angles. The rolling experiment under different forming angles was done on H500 rolling mill to calculate and analysis of the areas of the centre holes for each rolled piece. The influence of forming angle on internal defect is discovered by a method combining finite element simulation and experiments. At last, it is concluded that forming angle of 28°can improve the internal defect of valve roughcast formed by single cross wedge rolling.

Abstract: Deep study on Inside Right-angle Step (IRS) forming process was conducted to improve the precision of its (IRS) forming. According to its actual forming process, the zone, or the undeformed zone, was looked as semi-spiral declined cone and excluded the contact zone. A new algorithm was developed for calculating the size of the undeformed zone. More simple mathematical models and expressions weredeveloped for solving the shaping curve. The model was verified in terms of its simplicity and correctness based on the numerical simulation.

Abstract: . Determining axial movement displacement is a key question for designing the die which is used to form asymmetric shaft parts by CWR. FE model is established in this paper, the rule of process parameters influence on axial movement displacement is also analyzed, and then influence factors on axial movement displacement are gotten. The rule is that forming angle, spreading angle and area reduction have effect on axial movement displacement; rolling temperature and the diameter of rolled part has no effect on it. The conclusion provides the foundation for further determining axial movement displacement accurately.

Abstract: Axial force in CWR is an important force and energy parameter for stable rolling, which plays an important role in studying the forming quality of asymmetric shaft-parts, section shrinkage of rolled parts and rolling of heavy area reduction. By simplifying boundary conditions of solving axial projected area in this paper, and considering the effects of frictional force generated by contact surfaces between the tools and shaped shaft-section, the formula of the axial force has been derived by analytical method; by comparison of axial force values simulated by ANSYS/LS-DYNA FE software and measured through experiment, the formula of the axial force is verified correctly. The analyzing results provide useful reference for solving process problems caused by axial force.