空心六角法兰面螺栓冷挤压成形工艺与同心度分析  

Cold extrusion process and concentricity analysis on hollow hexagonal flange bolts

作　　者：朱景秋 张东民 吕雷雷 周伟民 Zhu Jingqiu;Zhang Dongmin;Lyu Leilei;Zhou Weimin(Shanghai Physical Vapor Deposition(PVD)Superhard Coating and Equipment Engineering Technology Research Center,Shanghai Institute of Technology,Shanghai 201418,China;Shanghai Dongfeng Automobile Special Parts Co.,Ltd.,Shanghai 201419,China)

机构地区：[1]上海应用技术大学上海物理气相沉积(PVD)超硬涂层及装备工程技术研究中心,上海201418 [2]上海东风汽车专用件有限公司,上海201419

出　　处：《锻压技术》2020年第3期70-76,共7页Forging & Stamping Technology

基　　金：企业横向项目(J2017-184)。

摘　　要：分析了金属反挤压时内部各质点的流动规律与空心六角法兰面螺栓的结构特征,其最大特点是在保证同心度为0.2 mm的前提下,成形孔径比高达6.5的深孔,并初步设计4工位冷挤压成形工艺。运用DEFORM-3D重点研究了工序3深孔预成形过程,在刚性平移区选取4个点,利用点追踪方法,以所选点的径向偏移量为评价标准,研究了圆锥凸模、平底锥形凸模、球头凸模和平底凸模4种凸模结构对深孔同心度的影响程度。同时,对比成形初期金属流动情况、行程载荷,综合结果表明:圆锥凸模能在较低的成形载荷下得到良好的金属流线,有利于提高制件同心度。最后,通过JBF-19B-4S螺栓冷镦机进行试模,生产出成形饱满、无缺陷,且同心度达到设计要求的制件,为深孔类零件冷挤压成形提供了一种参考。The flow law of internal mass points and the structural characteristics of hollow hexagonal flange bolts during reverse extrusion were analyzed,its main feature was to form deep holes with a hole diameter ratio of 6.5 on the premise of ensuring the concentricity of 0.2 mm,and the four-station cold extrusion process was preliminarily designed.Then,the pre-forming process of deep hole in step 3 was studied by DEFORM-3D,and four points were selected in the rigid translation area to study the influences of four punch structures such as conical punch,conical punch with flat bottom,ball head and flat bottom on the concentricity of deep holes by point tracking method and on the radial offset of selected points was taken as the evaluation criterion.At the same time,compared with the metal flow and the travel load in the initial stage of forming,the comprehensive results show that the conical punch gets good metal streamline under lower forming load,which is conducive to improving the concentricity of parts.Finally,the full-formed and defect-free parts with concentricity meeting the design requirements are produced by JBF-19B-4S bolt cold heading machine,which provides a reference for cold extrusion forming of deep-hole parts.

关 键 词：空心六角法兰面螺栓 冷挤压 反挤压 凸模结构 同心度 

分 类 号：TG376[金属学及工艺—金属压力加工]