新型8MN/3MN钢管管端加厚机的开发

介绍新型8MN3 MN钢管管端加厚机的整体结构,重点分析其肘杆增力机构原理;通过与传统钢管管端加厚机的对比发现,研发的新型肘杆增力机构式钢管管端加厚机具有结构简单,生产效率高,性能稳定,节能降耗效果显著等优势。     

成形条件对大型环件径轴向轧制成形影响研究

环件径轴向轧制成形技术是生产大型高品质无缝环件的最佳加工方法。对大型环件径轴向轧制成形工艺进行了深入研究,通过对比分析不同材料和径轴向进给比条件下的环件变形状态,揭示了成形条件对大型环件径轴向轧制成形的影响规律。研究发现:动态再结晶效应好的铝合金环件材料在径轴向轧制成形时比碳钢环件变形更不均匀,成形过程截面质量更差,为了增加环件径轴向轧制的材料变形均匀性,可以适当地降低环件的成形温度,特别是环件表面的温度;对于厚度和高度尺寸相当的环件产品,在其他成形条件相同时,较大的径轴向压下比可以提高环件的变形均匀性。     

AZ31镁合金薄壁管分流挤压速度影响规律仿真研究

基于DEFORM-3D平台,以军用战地发射塔天线用AZ31镁合金薄壁管分流挤压工艺过程为研究对象,研究建立了精确、高效的AZ31镁合金薄壁管分流挤压有限元模型。模拟研究揭示了挤压速度对挤压力、焊合压力及模口坯料金属峰值温度的影响规律。基于所得规律,综合考虑挤压力、焊合质量及挤出管材表面质量要求,获得了该规格AZ31镁合金薄壁管在2000t挤压机上的合理挤压速度范围为3.5~7mm/s。     

超大型环件径向轧制设备动梁受力分析和优化

本研究建立了超大型环件径向轧制设备动梁的有限元模型,采用该模型对超大型环件径向轧制设备动梁的受力进行了分析.研究发现,前梁框架的厚度和其中筋板厚度对前梁的强度和刚度都有较大的影响,而且其整体厚度的影响更大,本文基于动梁的有限元计算结果对动梁结构进行了优化设计,获得了可以满足设备功能需求的动梁结构.     

基于虚拟正交试验的Inconel690合金大口径厚壁管挤压工艺仿真

研究挤压成形参数影响规律并确定合理的参数取值范围,是开发难变形合金大型型材挤压工艺技术和挤压过程精细化控制,以及大吨位(如2万吨)挤压机的研发、调试及应用迫切需要开展的重要内容。基于DEFORM-2D平台,以规格为Ф420mm×60mm的难变形Inconel690合金管材穿孔针挤压为研究对象,建立了适用、可靠的无缝管材穿孔针挤压过程的有限元仿真模型;选取挤压比λ、模角α、定径带长度h、坯料初始温度T、挤压速度v等重要成形参数为影响因素,以坯料温度峰值Tmax、坯料金属损伤峰值Dmax、模口坯料金属流速均方差Fsdv和挤压力峰值Lmax为衡量指标,开展了基于模拟仿真的虚拟正交试验研究。结果表明,影响Tmax、Dmax、Fsdv、Lmax的因素主次顺序分别为:T>v>λ>h>α、α>v≈λ>T>h、h>v>T>α>λ、λ>T>α>v>h;综合考虑成形管材质量、挤压力等因素,获得了2万吨难变形合金卧式挤压机上挤压该规格Inconel690合金管材的合理成形参数取值范围为:λ=5.74～6.37、α=35～45°、h=60～120mm、T=1080～1180℃、v=150～250mm/s。     

我国有色加工装备业快速发展

十一五期间,我国的有色金属加工装备业经历了快速发展,取得了重大进步,为十二五的发展奠定了良好的基础。     

Effect of frictions on cross section quality of thin-walled tube NC bending

1 Introduction Thin-walled tube bending parts have been increasingly used in many industry fields such as aviation, aerospace and automobile for their easy satisfaction in light weight, high strength and low consuming. The numerical controlled(NC) rotar…     

Forming characteristics of thin-walled tube bending process with small bending radius

Currently requirements of thin-walled tube with small bending radius cause the defects such as wrinkling, overthinning and cross-section distortion more prone to occur in bending process. Based on the analysis of the forming characteristics by analytical and experimental methods, a complete 3D elastic-plastic FEM model of the process was developed using ABAQUS/Explicit code, including bending process, balls retracting and unloading process, and thus the plastic deformation characteristics with small bending radius were investigated. The main results show that： 1） The utmost deformation feature of the NC bending process is its continuous progressive deformation. 2） The occurring conditions of the defects such as wrinkling and tension instability in the process are obtained. The wrinkling is traditional on the double compressive stresses state and the tension instability is on the double tension stresses state. 3） The enhanced non-uniform deformation in thin-walled tube with small bending radius is demonstrated by comparing the stress/strains distributions under the 1.5D and lD bending conditions. 4） For lD small bending process, a new method-＂stepped mandrel retraction＂ is proposed to improve the bending quality in experiment according to the FE simulation. The simulation results are verified by experiment.     

卧式双动锆挤压生产线

40 MN卧式双动锆挤压生产线是我国第一条核级锆管生产线上的关键设备,具有完全自主知识产权,适应于锆管特别是难变形的核级锆管的挤压加工,可以实现锆管的扩孔/不扩孔、有压余/无压余、涂层/包铜润滑挤压加工。本文简要介绍了该生产线的特点、结构、主要参数和锆合金挤压的工艺特点。