一种Zr-4厚壁管矫直行程计算方法

A Straightening Stroke Algorithm of Zr-4 Alloys Thick Walled Pipe

摘要:

Zr-4厚壁管件是核电站燃料供给系统中重要零件，挤压成形后需要三点弯矫直工艺减少后续加工量。其矫直过程是微小弹塑性变形过程，通过分析弹性、弹塑性和回弹三阶段的应力应变变化，形成管件M-?-?方程，反映弹塑性弯曲变形和卸载间关系。基于Zr-4管材料特性，建立弹性线性强化本构模型，计算矫直挠度，提出Zr-4厚壁管矫直行程计算方法。经过对多根最大弯曲变形20mm，具有6个检测点、长5m厚壁Zr-4管进行矫直实验，矫直后弯曲量均小于0.50mm，矫直时间由手工矫直1.5h/根减少到22.5min/根，表明该矫直行程计算方法具有一定的实用性。

Abstract:

Zr-4 alloys thick walled pipes are the important parts in nuclear power station fuel supply system, its processing capacity can be reduced through three points straightening after extrusion. The micro stress and strain variation during pipe elastic deformation, elastic-plastic deformation, and rebound deformation had been analyzed based on elastic-plastic theory, and built the M-?-? equation, which can express the relation between elastic-plastic bending deformation and unloading procedure. The Zr-4 alloys thick walled pipes elastic -linear hardening constitutive model had been built based on material characteristics to computer the straitening deformation and proposed a straightening stroke algorithm of Zr-4 alloys thick walled pipe. Several 5m length pipes with the maximum deformation more than 20mm, 6 detecting points had been used straightening experiment, and all of pipe’s straightness were less than 0.50mm and the straightening time reduced from 1.5h/pcs by hand-straightening to 22.5min/pcs automation, and the results indicate that the algorithm practical is good.