汽车发电机定子焊接变形的矫正技术研究
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摘要
随着汽车工业的发展,汽车上的电子控制装置和用电设备相应增加,用电量也随着提高。体积小而输出功率大的汽车交流发电机己成为一个重要的发展趋势。传统发电机定子铁芯制造存在的问题是采用冲压工艺制造钢片时废料多,焊接时定位麻烦,经济性较差。将汽车发电机定子铁芯改进为由带有齿的钢带卷绕结构,取代冲压钢片叠加式结构,焊接后定子铁芯的椭圆度较大,需要进行矫形等后续处理。研究定子铁芯焊接变形和焊后矫形具有重要的意义。
首先,本文使用非线性有限元模拟了定子铁芯钢圈受挤压作用的变形情况,为铁芯钢圈的尺寸选择提供了有益的指导。其次,选取焊缝成形优良、焊接变形小、熔宽较窄、熔深较大的等离子弧焊接方法,焊接时使用六把焊枪同时施焊,通过实验探索出发电机定子铁芯钢圈焊接的最佳焊接工艺。铁芯钢圈采用多层钢带叠加后进行焊接,由于钢带经卷绕后会发生塑性变形,产生一定的内应力,会发生层层分离。因此,需要进行有效约束后才能进行焊接。同时,为了保证焊接过程中钢圈内侧小槽不发生较大的变形,在每个槽孔内要使用凸起的刚性约束;而钢圈外部也不能发生较大变形,又研制了适用于钢圈层叠后焊接的特殊焊接夹具。试验结果表明,此焊接夹具有效控制了焊接后变形。最后,焊接时近缝区金属由于加热不均匀,导致横向收缩沿钢圈厚度上分布不均匀而产生角变形,从而使圆度发生变化。本文首次提出采用过盈的刚性模具内撑钢圈来实施焊后矫形,使用有限元模拟分析和设计了最佳矫圆模具尺寸,通过矫形处理后,焊接变形从0.32mm左右减小到0.09mm范围内,满足定子铁芯设计尺寸要求。
As the development of motor vehicle industry, the demand for the electrical controlling installation and electro-equipment is increasing, leading to the increment of electric sources consumption. Thus it is significant to use the motor vehicle alternating generator which has small volume but large output horsepower. There are many problems existing in traditional production of generator stator iron core. For example, there is much scrap during the production of sheet steel by the press technology, and it is hard to fix during the welding process, also the economical efficiency is bad. There is a new technique that makes the stator iron core of the motor vehicle generator by the curled the steel strip with groove, instead of the punch structure with punched steel strip. The ellipticity of the stator iron core is large after welding, so it’s necessary to rectify after the welding. Thus it is meaningful to study the welding distortion and post-welding rectification of the stator iron core.
First of all, using the nonlinear finite element method to simulate the distortion of the stator iron core steel ring during the pressing, which gives helpful guidance to select the size of the steel core steel ring. On the other hand, The plasma arc welding method has been used due to its excellent appearance of weld bead, small welding distortion, narrow molten pool width, large penetration. Six welding guns are used simultaneously and the parameters are optimized during the welding process. The iron core steel ring is made up of multilayer steel strips before welding, there are new problems after steel strips wrapping around, such as the occurring of plastic distortion and the interior stress, and the separation of steel strip from each other. Thus it is necessary to give effective restriction before welding. At the same time, rigid project restriction is used inside the every slot to limit the large distortion of the small slots of the steel ring during the welding process. Meanwhile, special welding clamp for tiering steel ring which is fit for welding are also designed to restrict the large distortion of the outside of the steel ring. And the experimental results show that the welding clamp can control the slot distortion after welding effectively. At last, as the heat in the metal around weld bead is nonhomogeneous during the welding process, it causes the unhomogeneous transverse contraction along the thickness of the steel ring, which may lead to the angular distortion and the distortion of the roundness. The excessive rigid moulds to rectify steel ring is designed to realize distortion rectification after welding. The best roundness rectification size of mould is obtained by finite element simulation and it is used to rectify the welding distortion. After the distortion rectification, the welding distortion is reduced from 0.32mm to 0.09mm which meets the design demand of stator iron core.
首先,本文使用非线性有限元模拟了定子铁芯钢圈受挤压作用的变形情况,为铁芯钢圈的尺寸选择提供了有益的指导。其次,选取焊缝成形优良、焊接变形小、熔宽较窄、熔深较大的等离子弧焊接方法,焊接时使用六把焊枪同时施焊,通过实验探索出发电机定子铁芯钢圈焊接的最佳焊接工艺。铁芯钢圈采用多层钢带叠加后进行焊接,由于钢带经卷绕后会发生塑性变形,产生一定的内应力,会发生层层分离。因此,需要进行有效约束后才能进行焊接。同时,为了保证焊接过程中钢圈内侧小槽不发生较大的变形,在每个槽孔内要使用凸起的刚性约束;而钢圈外部也不能发生较大变形,又研制了适用于钢圈层叠后焊接的特殊焊接夹具。试验结果表明,此焊接夹具有效控制了焊接后变形。最后,焊接时近缝区金属由于加热不均匀,导致横向收缩沿钢圈厚度上分布不均匀而产生角变形,从而使圆度发生变化。本文首次提出采用过盈的刚性模具内撑钢圈来实施焊后矫形,使用有限元模拟分析和设计了最佳矫圆模具尺寸,通过矫形处理后,焊接变形从0.32mm左右减小到0.09mm范围内,满足定子铁芯设计尺寸要求。
As the development of motor vehicle industry, the demand for the electrical controlling installation and electro-equipment is increasing, leading to the increment of electric sources consumption. Thus it is significant to use the motor vehicle alternating generator which has small volume but large output horsepower. There are many problems existing in traditional production of generator stator iron core. For example, there is much scrap during the production of sheet steel by the press technology, and it is hard to fix during the welding process, also the economical efficiency is bad. There is a new technique that makes the stator iron core of the motor vehicle generator by the curled the steel strip with groove, instead of the punch structure with punched steel strip. The ellipticity of the stator iron core is large after welding, so it’s necessary to rectify after the welding. Thus it is meaningful to study the welding distortion and post-welding rectification of the stator iron core.
First of all, using the nonlinear finite element method to simulate the distortion of the stator iron core steel ring during the pressing, which gives helpful guidance to select the size of the steel core steel ring. On the other hand, The plasma arc welding method has been used due to its excellent appearance of weld bead, small welding distortion, narrow molten pool width, large penetration. Six welding guns are used simultaneously and the parameters are optimized during the welding process. The iron core steel ring is made up of multilayer steel strips before welding, there are new problems after steel strips wrapping around, such as the occurring of plastic distortion and the interior stress, and the separation of steel strip from each other. Thus it is necessary to give effective restriction before welding. At the same time, rigid project restriction is used inside the every slot to limit the large distortion of the small slots of the steel ring during the welding process. Meanwhile, special welding clamp for tiering steel ring which is fit for welding are also designed to restrict the large distortion of the outside of the steel ring. And the experimental results show that the welding clamp can control the slot distortion after welding effectively. At last, as the heat in the metal around weld bead is nonhomogeneous during the welding process, it causes the unhomogeneous transverse contraction along the thickness of the steel ring, which may lead to the angular distortion and the distortion of the roundness. The excessive rigid moulds to rectify steel ring is designed to realize distortion rectification after welding. The best roundness rectification size of mould is obtained by finite element simulation and it is used to rectify the welding distortion. After the distortion rectification, the welding distortion is reduced from 0.32mm to 0.09mm which meets the design demand of stator iron core.
引文
1.田锡唐.焊接结构.机械工业出版社, 1982:5~16
2. R. A. Chihoski. Expansion and Stress around Aluminum Weld Puddles. Welding Journal. 1979, (12):263~276
3.林德超,史耀武,蔡洪能.强度和线膨胀系数匹配对焊接残余应力的影响规律.压力容器. 1996, 13(6):27~31
4.张玉凤,霍立兴,王立君.焊缝匹配对力学性能影响的综合研究.机械工程学报. 1994, 30(3):31~38
5.魏良武.固有应变法预测焊接变形的研究及其工程应用.上海交通大学博士学位论文. 2004:58~76
6.陈积光,豆志武,赖伟栋.焊接钛制压力容器中残余应力的研究.焊接技术. 2001, 30(2):40~41
7. F. W. Bornscheuer. The Effect of Residual Welding Stresses on Buckling Strength. Rivista Italiana Della Saldatura. 1990, (3):18~25
8. C. L. Tsal, S. C. Park and W. T. Cheng. Welding Distortion of a Thin-Plate Panel Structure. Welding Journal. 1999, (5):156~165
9. Lytle Johnson. Formation of Plastic Strain during Welding of Aluminum Alloy. Welding Journal. 1973, (7):298~305
10. Jonsson, B. L. Josefson. Experimentally Determined Transient and Residual Stresses in a Butt-welded Pipe. Journal of Strain Analysis. 1988, 23(1):25~31
11. J. Lu, C. Bouhelier and H. P. Lieurade. Study of Residual Welding Stress Using the Step-by-step Hole Drilling and X-ray Diffraction Method. Welding in The World. 1994, 33(8):118~128
12.兰春萍,张玉凤.管道结构环焊缝焊接残余应力的计算与测量.焊接技术. 1999, (4):5~6
13.刘伟平.控制高温铝合金焊接热裂纹与焊接变形的新方法.哈尔滨工业大学博士论文. 1989:80~95
14.任登义,魏星,王育福等.铸铁冷焊锤击力的测定及锤击效果分析.焊接. 1998, (1):12~15
15.邹增大,王新洪,曲仕尧.锤击消除焊接接头残余应力的数值模拟.中国机械工程. 2000, 21(2):466~468
16.夏丕旭,董亚辉,董增田.锤击法提高焊接接头疲劳强度新技术途径探讨.焊接. 1991, (12):2~6
17. J. E. Braid, R. Bell and D. V. Militaru. Fatigue Life of As-Welded, Repaired, and Hammer-Peened Joints in High-Strength Structural Steel. Welding in the World. 1996, 37(2):248~262
18.徐文立,黎明,刘雪松等.动态低应力小变形无热裂随焊锤击焊接技术研究.材料科学与工艺. 2001, 9(1):6~10
19.徐文立,田锡唐,刘雪松.随焊锤击对LY12CZ焊接接头力学性能的影响.材料科学与工艺. 2001, 9(3):33~35
20. Xu Wenli, Tian Xitang and Liu Xuesong. A New Method for Welding Aluminum Alloy LY12CZ Sheet with High Strength. China Welding. 2001, 10(2):121~127
21.徐文立,田锡唐,刘雪松.随焊锤击对LY12CZ焊接接头显微组织的影响.哈尔滨工业大学学报. 2001, 33(4):442~446
22. P. Michaleris, X. Sun. Finite Element Analysis of Thermal Tensioning Techniques Mitigation Weld Buckling Distortion Residual Stress in Design, Fabrication, Assessment and Repaired. R. W. Warke. ASME PVP. 1996, 32 (7):77~79
23. P. Michalaras. Prediction and Minimization of Welding Induced Distortion. International institute of Welding (IIW-X/XV-RSDP-10-97). Paris, 1997:95~99
24. U. I. Birmanetal. Welding Research Abroad. 1985, (12):33~35
25.关桥,崇显,郭德伦.动态控制的低应力无变形焊接新技术.焊接学报. 1994, 15 (1):8~15
26.孟详定.论焊接变形及防治措施.中国锅炉压力容器安全. 1998, 14(4):15~17
27.张勇军.提高大型轴类锻件横向力学性能的新工艺研究.燕山大学硕士学位论文. 1997:13~14
28. U. Chandra,S.Rachakonda,S.Chandrasekharan.Total Quality Management of Forged Products through Finite Element Simulation.In:Proceeding of the Third Internationa SAMPE Metals Conference. 1992, (32):379~393
29.胡敏,林忠钦,徐伟力.车身覆盖件冲压成形动态仿真的研究进展.力学进展. 2000, 30(2): 252~272
30.胡军峰. 10Ni5CrMoV钢耐压壳圈制造过程中应力场的有限元分析.哈尔滨工业大学博士论文. 2000:17~20
31.赵耀邦.双向预置应力控制焊接变形及防止热裂纹研究.哈尔滨工业大学硕士论文. 2007:29
32.潘华.机械拉伸控制A3钢板壳结构的变形.哈尔滨工业大学硕士论文. 2000:11~26
33.杨春利,林三宝.电弧焊基础.哈尔滨工业大学出版社, 2003:45~54
34. Kou, Y. Le. Improving Weld Quality by Low Frequency Arc Oscillation. Welding Journal. 1985, 64(3):51~55
35.冯春生.焊接冶金学.机械工业出版社, 2007:23~86
36. Pavelic V, Tanbakuchi R, Auyehara O. Experimental and Computed Temperature Histories in Gas Tungsten arc Welding of Thin Plates. Welding Journal Research Supplement. 1969, 48(7): 295~305
37. J.Goldak, A.Chakravarti, M.Bibby. A New Finite Model for Welding Heat Source Metallurgua. Transactions. 1984, 15 (2): 299~305
38.莫春立,钱百年,国旭明.焊接热源计算模式的研究进展.焊接学报. 2001, 22(3): 93~96
39.汪建华.多层焊焊接接头横向收缩和角变形的计算机预测.造船技术. 1987, (1):34~38
40. C.A.库兹米罗夫.船体结构的焊接变形.国防工业出版社, 1978, (1):37~162
41.杨冠东译.窄间隙GMA焊接时大厚度圆筒纵焊缝焊接变形的预测.国外焊接. 1987, (6):45~46
42.谭秀安.压力容器焊接角变形的控制.焊接技术. 1990, (3):33~34
43.唐超.大直径法兰焊接变形的防止.电焊机. 1991, (1):38~40
2. R. A. Chihoski. Expansion and Stress around Aluminum Weld Puddles. Welding Journal. 1979, (12):263~276
3.林德超,史耀武,蔡洪能.强度和线膨胀系数匹配对焊接残余应力的影响规律.压力容器. 1996, 13(6):27~31
4.张玉凤,霍立兴,王立君.焊缝匹配对力学性能影响的综合研究.机械工程学报. 1994, 30(3):31~38
5.魏良武.固有应变法预测焊接变形的研究及其工程应用.上海交通大学博士学位论文. 2004:58~76
6.陈积光,豆志武,赖伟栋.焊接钛制压力容器中残余应力的研究.焊接技术. 2001, 30(2):40~41
7. F. W. Bornscheuer. The Effect of Residual Welding Stresses on Buckling Strength. Rivista Italiana Della Saldatura. 1990, (3):18~25
8. C. L. Tsal, S. C. Park and W. T. Cheng. Welding Distortion of a Thin-Plate Panel Structure. Welding Journal. 1999, (5):156~165
9. Lytle Johnson. Formation of Plastic Strain during Welding of Aluminum Alloy. Welding Journal. 1973, (7):298~305
10. Jonsson, B. L. Josefson. Experimentally Determined Transient and Residual Stresses in a Butt-welded Pipe. Journal of Strain Analysis. 1988, 23(1):25~31
11. J. Lu, C. Bouhelier and H. P. Lieurade. Study of Residual Welding Stress Using the Step-by-step Hole Drilling and X-ray Diffraction Method. Welding in The World. 1994, 33(8):118~128
12.兰春萍,张玉凤.管道结构环焊缝焊接残余应力的计算与测量.焊接技术. 1999, (4):5~6
13.刘伟平.控制高温铝合金焊接热裂纹与焊接变形的新方法.哈尔滨工业大学博士论文. 1989:80~95
14.任登义,魏星,王育福等.铸铁冷焊锤击力的测定及锤击效果分析.焊接. 1998, (1):12~15
15.邹增大,王新洪,曲仕尧.锤击消除焊接接头残余应力的数值模拟.中国机械工程. 2000, 21(2):466~468
16.夏丕旭,董亚辉,董增田.锤击法提高焊接接头疲劳强度新技术途径探讨.焊接. 1991, (12):2~6
17. J. E. Braid, R. Bell and D. V. Militaru. Fatigue Life of As-Welded, Repaired, and Hammer-Peened Joints in High-Strength Structural Steel. Welding in the World. 1996, 37(2):248~262
18.徐文立,黎明,刘雪松等.动态低应力小变形无热裂随焊锤击焊接技术研究.材料科学与工艺. 2001, 9(1):6~10
19.徐文立,田锡唐,刘雪松.随焊锤击对LY12CZ焊接接头力学性能的影响.材料科学与工艺. 2001, 9(3):33~35
20. Xu Wenli, Tian Xitang and Liu Xuesong. A New Method for Welding Aluminum Alloy LY12CZ Sheet with High Strength. China Welding. 2001, 10(2):121~127
21.徐文立,田锡唐,刘雪松.随焊锤击对LY12CZ焊接接头显微组织的影响.哈尔滨工业大学学报. 2001, 33(4):442~446
22. P. Michaleris, X. Sun. Finite Element Analysis of Thermal Tensioning Techniques Mitigation Weld Buckling Distortion Residual Stress in Design, Fabrication, Assessment and Repaired. R. W. Warke. ASME PVP. 1996, 32 (7):77~79
23. P. Michalaras. Prediction and Minimization of Welding Induced Distortion. International institute of Welding (IIW-X/XV-RSDP-10-97). Paris, 1997:95~99
24. U. I. Birmanetal. Welding Research Abroad. 1985, (12):33~35
25.关桥,崇显,郭德伦.动态控制的低应力无变形焊接新技术.焊接学报. 1994, 15 (1):8~15
26.孟详定.论焊接变形及防治措施.中国锅炉压力容器安全. 1998, 14(4):15~17
27.张勇军.提高大型轴类锻件横向力学性能的新工艺研究.燕山大学硕士学位论文. 1997:13~14
28. U. Chandra,S.Rachakonda,S.Chandrasekharan.Total Quality Management of Forged Products through Finite Element Simulation.In:Proceeding of the Third Internationa SAMPE Metals Conference. 1992, (32):379~393
29.胡敏,林忠钦,徐伟力.车身覆盖件冲压成形动态仿真的研究进展.力学进展. 2000, 30(2): 252~272
30.胡军峰. 10Ni5CrMoV钢耐压壳圈制造过程中应力场的有限元分析.哈尔滨工业大学博士论文. 2000:17~20
31.赵耀邦.双向预置应力控制焊接变形及防止热裂纹研究.哈尔滨工业大学硕士论文. 2007:29
32.潘华.机械拉伸控制A3钢板壳结构的变形.哈尔滨工业大学硕士论文. 2000:11~26
33.杨春利,林三宝.电弧焊基础.哈尔滨工业大学出版社, 2003:45~54
34. Kou, Y. Le. Improving Weld Quality by Low Frequency Arc Oscillation. Welding Journal. 1985, 64(3):51~55
35.冯春生.焊接冶金学.机械工业出版社, 2007:23~86
36. Pavelic V, Tanbakuchi R, Auyehara O. Experimental and Computed Temperature Histories in Gas Tungsten arc Welding of Thin Plates. Welding Journal Research Supplement. 1969, 48(7): 295~305
37. J.Goldak, A.Chakravarti, M.Bibby. A New Finite Model for Welding Heat Source Metallurgua. Transactions. 1984, 15 (2): 299~305
38.莫春立,钱百年,国旭明.焊接热源计算模式的研究进展.焊接学报. 2001, 22(3): 93~96
39.汪建华.多层焊焊接接头横向收缩和角变形的计算机预测.造船技术. 1987, (1):34~38
40. C.A.库兹米罗夫.船体结构的焊接变形.国防工业出版社, 1978, (1):37~162
41.杨冠东译.窄间隙GMA焊接时大厚度圆筒纵焊缝焊接变形的预测.国外焊接. 1987, (6):45~46
42.谭秀安.压力容器焊接角变形的控制.焊接技术. 1990, (3):33~34
43.唐超.大直径法兰焊接变形的防止.电焊机. 1991, (1):38~40