间隙对0Cr18Ni9不锈钢管大曲率无芯弯曲成形性的影响

Effect of Clearance on Formability of Large Curvature Bending without Mandrel for 0Cr18Ni9 Stainless Steel Tube

基于Abaqus有限元平台建立了0Cr18Ni9不锈钢管大曲率无芯弯曲有限元模型,分析了管材与模具间隙对管材弯曲成形性的影响,同时验证了模型可靠性。结果表明:弯管外凸侧壁厚减薄率与管-弯曲模间隙、管-压力模间隙呈正相关关系,而与管-防皱模间隙呈负相关关系;弯管内凹侧壁厚增厚率与管-弯曲模间隙、管-防皱模间隙呈正相关关系,而与管-压力模间隙呈负相关关系;弯管横截面椭圆度与管-弯曲模间隙、管-压力模间隙呈正相关关系,而与管-防皱模间隙呈负相关关系;管材与模具间隙对壁厚减薄率及横截面椭圆度影响的趋势一致。

Based on Abaqus finite element platform, the finite element model of large curvature bending without mandrel for 0Cr18Ni9 stainless steel tube was established. The influence of the gap between pipe and die on the bending formability of the pipe was analyzed, and the reliability of the model was verified. The results show that there is a positive correlation between the wall thinning rate of bent tube at the outer convex side and the tube-bending die clearance, tube-pressure die clearance, but it has a negative correlation between the wall thinning rate and tube-wiper die clearance;there is a positive correlation between the wall thickening rate of bent tube at the inner concave side and the tube-bending die clearance,tube-wiper die clearance, but it has a negative correlation between the wall thickening rate and tube-pressure die clearance;there is a positive correlation between the cross-section ovality of bent tube and the tube-bending die clearance, tube-pressure die clearance, but it has a negative correlation between the cross-section ovality and tube-wiper die clearance;the effect of tube-dies clearance on wall thinning rate and cross-section ovality is consistent.