摘要
制管坯是P91钢质厚壁管热挤压生产的主要变形工序。以某规格外径为Φ535 mm、内径为Φ250 mm、长度为1900 mm的P91钢质厚壁管坯为对象,利用Forge软件平台对其反挤压制管坯过程进行了数值模拟,得到了随凸模行程变化的温度场分布和挤压力大小,确定了温度场存在两处局部高温区域,即凸模头部正下方和管坯出流口处;挤压力随凸模行程存在缓慢、线性、逐渐和急剧增大的阶段性特征。通过坯料初始温度和挤压速度对制管坯过程的影响研究,确定了坯料初始温度能够显著降低最大挤压力,而增大挤压速度也对降低最大挤压力有一定作用。实际生产推荐坯料初始温度选用区间为1100-1200℃,挤压速度为200 mm·s-1,设备吨位为36 MN。
Making tube billet is the main deformation procedure of hot extrusion production for thick wall P91 steel tube.For thick wall P91 steel tube billet,with an outer diameter of Φ535 mm,an inner diameter of Φ250 mm and a length of 1900 mm,the numerical simulation of backward extrusion process was carried out by Forge software.The temperature field distribution and extrusion force with the changes of punch stroke were obtained.The two local high temperature zones in the temperature field were confirmed,namely the area vertically below the punch head and the outflow location of tube billet.Moreover,the extrusion force had the stage characteristic of slow,linear,gradual and rapid increasing with the increase of punch stroke.Through studying on effects of both the initial temperature and the extrusion speed on making tube billet process,it is showed that the increases of billet initial temperature and extrusion speed can decrease the max extrusion force obviously.Thereforce,the billet initial temperature of 1100-1200 ℃,extrusion speed of 200 mm·s-1and equipment tonnage of 36 MN have been recommended in the practical production.
出处
《锻压技术》
CAS
CSCD
北大核心
2014年第11期145-149,共5页
Forging & Stamping Technology
基金
山西省科技创新项目(2013101012)
关键词
P91钢
管坯
反挤压
数值模拟
P91 steel
tube billet
backward extrusion
mumerical simulation
