内六方通孔圆柱螺栓精密冷挤压成形工艺研究
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摘要
针对内六方通孔圆柱螺栓的几何特点,借助于有限元模拟分析与冷挤压成形实验,对圆管坯料采用六棱柱芯棒冷镦挤成形与冷正挤压成形两种成形工艺在金属流动、成形缺陷以及成形载荷方面进行了比较分析。结果表明:采用冷镦挤工艺成形方法,内六方通孔充填不饱满、法兰部分容易出现折叠缺陷,成形载荷大。相较而言,正挤压工艺成形载荷小,法兰部分金属过渡流畅,没有形成裂纹、褶皱等缺陷,所得成形工件满足几何形状及尺寸要求,成形效果好。研究表明正挤压成形工艺是适用于内六方通孔圆柱螺栓大批量生产的一种成形工艺。
According to geometry feature of internal hexagon hollow bolt,two forming technologies,the cold upsetting-extrusion and the forward extrusion with hexagon mandrel,were adopted by using tubular billets,respectively. The metal flow,forming defect and forming load during the two forming processes were investigated based on the finite element simulation analysis and cold extrusion experiments.The results show that,in the cold upsetting-extrusion process,the underfilling defect occurs,the folding defects are induced easily on the flange parts of bolts and the value of deformation load is high. In contrast,in forward extrusion forming process,the deformation load is lower and the metal flow in the transition region of flange parts is smooth. The workpieces with satisfied shape and dimension are obtained,and the cracks,folds and other defects are not found. The research shows that the forward extrusion forming technology is a feasible process for mass production of hexagon hollow bolts.
According to geometry feature of internal hexagon hollow bolt,two forming technologies,the cold upsetting-extrusion and the forward extrusion with hexagon mandrel,were adopted by using tubular billets,respectively. The metal flow,forming defect and forming load during the two forming processes were investigated based on the finite element simulation analysis and cold extrusion experiments.The results show that,in the cold upsetting-extrusion process,the underfilling defect occurs,the folding defects are induced easily on the flange parts of bolts and the value of deformation load is high. In contrast,in forward extrusion forming process,the deformation load is lower and the metal flow in the transition region of flange parts is smooth. The workpieces with satisfied shape and dimension are obtained,and the cracks,folds and other defects are not found. The research shows that the forward extrusion forming technology is a feasible process for mass production of hexagon hollow bolts.
引文
[1]燕来荣.我国紧固件行业发展现状[J].金属制品,2011,37(1):7-10.YAN Lairong.Present situation of China fastener industry development[J].Steel Wire Productions,2011,37(1):7-10.
[2]祝其高,张先鸣.我国紧固件行业技术发展[J].金属制品,2010,36(1):11-13.ZHU Qigao,ZHANG Xianming.Technology development of domestic fastener industry[J].Steel Wire Productions,2010,36(1):11-13.
[3]肖海峰,张治民.温成形技术在镁合金汽车零件生产中的应用[J].科技情报开发与经济,2005,15(17):128-129.XIAO Haifeng,ZHANG Zhimin.The application of the warm forming technology in the production of magnesium alloy automobile parts[J].Sci-Tech Information Development&Economy,2005,15(17):128-129.
[4]洪慎章.冷挤压实用技术[M].北京:机械工业出版社,2014.HONG Shenzhang.Cold extrusion technology[M].Beijing:China Machine Press,2014.
[5]KUDO H.An upper-bound approach to plane-strain forging and extrusion—II[J].International Journal of Mechanical Sciences,1960,1(4):229-252.
[6]WANG Z J,LU J,WANG Z R.Numerical and experimental research of the cold upsetting-extruding of tube flanges[J].Journal of Materials Processing Technology,2001,110(1):28-35.
[7]HU X L,WANG Z R.Numerical simulation and experimental study on the multi-step upsetting of a thick and wide flange on the end of a pipe[J].Journal of Materials Processing Technology,2004,151(1):321-327.
[8]黄早文,徐开东,张志坤,等.管坯镦锻工艺仿真及优化[J].锻压技术,2006,31(6):9-12.HUANG Zaowen,XU Kaidong,ZHANG Zhikun,et al.Simulation and optimization of the upset forging process of tube parts[J].Forging&Stamping Technology,2006,31(6):9-12.
[9]张治民,董妍兰.轴套镦挤成形过程的计算机模拟与工艺优化[J].材料科学与工艺,1998,17(3):41-44.ZHANG Zhimin,DONG Yanlan.Computer simulation and process optimization of upsetting extrusion process of sleeve[J].Materials Science and Technology,1998,17(3):41-44.
[10]YOSHIDA H,SAWAKI Y,SAKAIDA Y,et al.Shaping of internal helical gear by two-step cold extrusion[J].Journal of the JSTP,2013,54:64-68.
[11]TAKASHI O,TAKAHIRO Y,JUNICHI Z,et al.Formability improvement by die-bearing grooves in tube extrusion with spiral inner projections[J].Procedia Engineering,2014,81(10):641-646.
[12]NEGENDANK M,MULLER S,REIMERS W.Extrusion of aluminum tubes with axially graded wall thickness and mechanical characterization[J].Procedia Cirp,2014,18(18):3-8.
[13]SRINIVASAN K,VENUGOPAL P.Direct and inverted open die extrusion(ODE)of rods and tubes[J].Journal of Materials Processing Technology,2004,153-154:765-770.
[14]郭成,赵静远,庄达.平面应变复合挤压金属变形规律的研究(Ⅱ)[J].材料科学与工艺,1983,2(1):81-88.GUO Cheng,ZHAO Jingyuan,ZHUANG Da.Study on deformations of plane strain compression extrusion metal(Ⅱ)[J].Materials Science and Technology,1983,2(1):81-88.
[2]祝其高,张先鸣.我国紧固件行业技术发展[J].金属制品,2010,36(1):11-13.ZHU Qigao,ZHANG Xianming.Technology development of domestic fastener industry[J].Steel Wire Productions,2010,36(1):11-13.
[3]肖海峰,张治民.温成形技术在镁合金汽车零件生产中的应用[J].科技情报开发与经济,2005,15(17):128-129.XIAO Haifeng,ZHANG Zhimin.The application of the warm forming technology in the production of magnesium alloy automobile parts[J].Sci-Tech Information Development&Economy,2005,15(17):128-129.
[4]洪慎章.冷挤压实用技术[M].北京:机械工业出版社,2014.HONG Shenzhang.Cold extrusion technology[M].Beijing:China Machine Press,2014.
[5]KUDO H.An upper-bound approach to plane-strain forging and extrusion—II[J].International Journal of Mechanical Sciences,1960,1(4):229-252.
[6]WANG Z J,LU J,WANG Z R.Numerical and experimental research of the cold upsetting-extruding of tube flanges[J].Journal of Materials Processing Technology,2001,110(1):28-35.
[7]HU X L,WANG Z R.Numerical simulation and experimental study on the multi-step upsetting of a thick and wide flange on the end of a pipe[J].Journal of Materials Processing Technology,2004,151(1):321-327.
[8]黄早文,徐开东,张志坤,等.管坯镦锻工艺仿真及优化[J].锻压技术,2006,31(6):9-12.HUANG Zaowen,XU Kaidong,ZHANG Zhikun,et al.Simulation and optimization of the upset forging process of tube parts[J].Forging&Stamping Technology,2006,31(6):9-12.
[9]张治民,董妍兰.轴套镦挤成形过程的计算机模拟与工艺优化[J].材料科学与工艺,1998,17(3):41-44.ZHANG Zhimin,DONG Yanlan.Computer simulation and process optimization of upsetting extrusion process of sleeve[J].Materials Science and Technology,1998,17(3):41-44.
[10]YOSHIDA H,SAWAKI Y,SAKAIDA Y,et al.Shaping of internal helical gear by two-step cold extrusion[J].Journal of the JSTP,2013,54:64-68.
[11]TAKASHI O,TAKAHIRO Y,JUNICHI Z,et al.Formability improvement by die-bearing grooves in tube extrusion with spiral inner projections[J].Procedia Engineering,2014,81(10):641-646.
[12]NEGENDANK M,MULLER S,REIMERS W.Extrusion of aluminum tubes with axially graded wall thickness and mechanical characterization[J].Procedia Cirp,2014,18(18):3-8.
[13]SRINIVASAN K,VENUGOPAL P.Direct and inverted open die extrusion(ODE)of rods and tubes[J].Journal of Materials Processing Technology,2004,153-154:765-770.
[14]郭成,赵静远,庄达.平面应变复合挤压金属变形规律的研究(Ⅱ)[J].材料科学与工艺,1983,2(1):81-88.GUO Cheng,ZHAO Jingyuan,ZHUANG Da.Study on deformations of plane strain compression extrusion metal(Ⅱ)[J].Materials Science and Technology,1983,2(1):81-88.