反极性弱等离子弧堆焊设备及电弧特性研究
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摘要
本文对反极性弱等离子弧基本特性、堆焊焊枪、控制系统的PLC应用进行了研究和设计。反极性弱等离子弧堆焊焊枪是由上枪体、下枪体及中间绝缘体三大部分组成,其中用双金属极取代正极性等离子枪的柱状实心钨极作上电极,用球面压缩喷嘴代替常规的锥形压缩喷嘴是反极性弱等离子弧堆焊焊枪的关键问题。该枪体的这两个特征是由反极性弱等离子弧的两个相应的稳定燃烧条件所决定的。经过实践证明,焊枪在实验过程中使用正常,焊件达到了工艺的要求。电极与焊枪烧损明显减少。
反极性弱等离子弧堆焊设备存在自动化水平低,精度差,效率低的问题,因此本文针对焊接技术自动化发展趋势,研制了一种PLC自动控制技术用于反极性弱等离子弧堆焊焊接设备,利用PLC控制焊枪、转胎、小车的运动,从而实现焊接过程的自动化。系统运行表明焊机具有控制精度高、安全性好、响应速度快、自动化程度高的特点,从而达到降低工人劳动强度、提高堆焊层金属质量和生产效率、降低废品率、操作方便、易维修的目的,特别对改善劳动条件和提高生产效率具有明显的实用意义。
分析了反极性弱等离子电弧的能量密度在不同气流量和气体含量的变化规律、电弧压力径向分布特性、电弧的热特性、反极性弱等离子弧的燃烧稳定性及静特性等特点。结果表明:反极性弱等离子弧具有较均匀的电弧压力,弧底部的电压径向分布、电流径向分布和阴极斑点的分布三者一致,均呈凹形分布,阴极斑点能量约占电弧有效能量50%,有90%以上的电流分布在内圆直径10mm的圆环区,通过保护气流可以控制能量密度。
The thesis had researched and designed the negative polarity weak plasma arc overlaying welding, overlaying welding gun and the control system of PLC. The negative polarity weak plasma arc overlaying welding composes top gun, under gun and isolator in the middle. The double metal electrode replaces full core tungsten electrode as the top gun of straight polarity plasma arc overlaying welding gun and sphere constricting nozzle replaces taper constricting nozzle are the key points of the negative polarity weak plasma arc overlaying welding gun. The two characters of gun are decided by the condition of negative polarity weak plasma arc's burning. It has been found that the gun was fine in the experiment and the welding piece achieved the request of technology. The overburning of electrode and welding gun reduce obviously.
There are some problems in negative polarity weak plasma arc overlaying welding equipment, such as low robotization, imprecision and low efficiency. Aiming at the trend of automatic welding development, one kind of PLC automatic control technology has been developed for specialized use of the negative polarity weak plasma arc overlaying welding in this paper. Automatic welding process was realized through PLC control of the welding torch movement. It was proved by systems operation that the welder has advantages of high control precision, high reliability, fast response speed, high automatic level. Consequently, it brings merits of reduced labor intensity, increased welding quality and productivity, lower rejection rate, convenient operation and maintenance.
Analyzed the influence of protection air current and content to energy density, the distribution graph of negative polarity weak plasma arc radial pressure, the heat distribution of plasma arc, the combustion stability and static characteristic graph of negative polarity plasma arc. The result indicate: negative polarity weak plasma arc has the same distribution of homogeneity arc pressure, the distribution graph of arc voltage, the distribution graph of arc current and distribution area of cathode spot, they all have saucer shape, cathode spot takes up 50% of the effective energy, 90% of the current distributes in an area of annulus that the internal is 10mm, energy density can be controlled by protection air current.
反极性弱等离子弧堆焊设备存在自动化水平低,精度差,效率低的问题,因此本文针对焊接技术自动化发展趋势,研制了一种PLC自动控制技术用于反极性弱等离子弧堆焊焊接设备,利用PLC控制焊枪、转胎、小车的运动,从而实现焊接过程的自动化。系统运行表明焊机具有控制精度高、安全性好、响应速度快、自动化程度高的特点,从而达到降低工人劳动强度、提高堆焊层金属质量和生产效率、降低废品率、操作方便、易维修的目的,特别对改善劳动条件和提高生产效率具有明显的实用意义。
分析了反极性弱等离子电弧的能量密度在不同气流量和气体含量的变化规律、电弧压力径向分布特性、电弧的热特性、反极性弱等离子弧的燃烧稳定性及静特性等特点。结果表明:反极性弱等离子弧具有较均匀的电弧压力,弧底部的电压径向分布、电流径向分布和阴极斑点的分布三者一致,均呈凹形分布,阴极斑点能量约占电弧有效能量50%,有90%以上的电流分布在内圆直径10mm的圆环区,通过保护气流可以控制能量密度。
The thesis had researched and designed the negative polarity weak plasma arc overlaying welding, overlaying welding gun and the control system of PLC. The negative polarity weak plasma arc overlaying welding composes top gun, under gun and isolator in the middle. The double metal electrode replaces full core tungsten electrode as the top gun of straight polarity plasma arc overlaying welding gun and sphere constricting nozzle replaces taper constricting nozzle are the key points of the negative polarity weak plasma arc overlaying welding gun. The two characters of gun are decided by the condition of negative polarity weak plasma arc's burning. It has been found that the gun was fine in the experiment and the welding piece achieved the request of technology. The overburning of electrode and welding gun reduce obviously.
There are some problems in negative polarity weak plasma arc overlaying welding equipment, such as low robotization, imprecision and low efficiency. Aiming at the trend of automatic welding development, one kind of PLC automatic control technology has been developed for specialized use of the negative polarity weak plasma arc overlaying welding in this paper. Automatic welding process was realized through PLC control of the welding torch movement. It was proved by systems operation that the welder has advantages of high control precision, high reliability, fast response speed, high automatic level. Consequently, it brings merits of reduced labor intensity, increased welding quality and productivity, lower rejection rate, convenient operation and maintenance.
Analyzed the influence of protection air current and content to energy density, the distribution graph of negative polarity weak plasma arc radial pressure, the heat distribution of plasma arc, the combustion stability and static characteristic graph of negative polarity plasma arc. The result indicate: negative polarity weak plasma arc has the same distribution of homogeneity arc pressure, the distribution graph of arc voltage, the distribution graph of arc current and distribution area of cathode spot, they all have saucer shape, cathode spot takes up 50% of the effective energy, 90% of the current distributes in an area of annulus that the internal is 10mm, energy density can be controlled by protection air current.
引文
[1]刘家浚．材料磨损原理及其耐磨性．北京：清华大学出版社，1993：62-72．
[2] Sare I.R., Mardel J.I., Hill A. J. Wear-resistant metallic and elastomeric materials in the mining and mineral processing industries-an overview. Wear, 2001(250):1-10.
[3]材料耐磨抗蚀及其表面技术概论．北京：机械工业出版社，1986．
[4]孙家枢．金属的磨损．北京：冶金工业出版社，1992：2-4．
[5]邵荷生，张清编．金属的磨损与耐磨材料．北京：机械工业出版社，1988：62-65．
[6]崔信昌编．等离子弧焊接和切割．北京：国防工业出版社，1988：54-65．
[7]冯国昌．焊接技术．凌河汽车制造厂．1996，1：22-23．
[8]王德权，胡毅均，李杰编．阀门用钴基合金及堆焊工艺．2000，5：19
[9]陈俐，潘春旭．耐磨堆焊金属组织分析．武汉交通科技大学学报，1998，(6)：327-329．
[10]刘政军．超硬质相在高温磨损中的行为及抗磨性．焊接学报，1999，(2)：120-125．
[11]徐滨士．表面工程与维修．北京：机械工业出版社，1996：120-131．
[12]磨损失效分析案例编委会．磨损失效分析案例汇集．北京：机械工业出版社，1985：38-66．
[13]李健．等离子弧模具堆焊修复新工艺．锻压技术，1997，4：60-61．
[14]赵唯，柳林．等离子堆焊技术的研究进展．材料导报，2005，5：19．
[15] Schweissen Schneiden Innovations in Welding Technology in 2000.Welding Research Abroad, Jul/Aug,2001,47(7):8-9.
[16]彭补之．国内外热喷焊概况．北京：全国机械工业系统热喷焊，1984．
[17]刘政军．铁基高温耐磨等离子弧喷焊合金及耐磨基理的研究．天津：天津大学，1995．
[18] Gary. R. Heath, John Skora. New materials and process developments for preventative maintenane and repair in cement plants Cement World. 1998(2):360-365.
[19] Wang Xibao, Liu Hua Metal powder thermal behaviour during the plasma transferred-arc surfacing process Surface and Coating Technology 1998(106): 156-161.
[20] Robert. W, Messier Jr. Principles of Welding. John Willy&Soms, INC, 1999.
[21]张德勤，杜则裕，屈朝霞．等离子弧粉末堆焊最佳工艺参数的研究．天津人学学报，1999，6：750-753．
[22] Wang Bibao, Zhang Wenyue. New longitudinal strengthening method for plasma arc powder surfacing coating. Transactions of Tianjin University, 2000(6), 2:157-161.
[23]王红英，程志国，赵昆等．新型等离子弧粉末堆焊机理．焊接学报，2002，4(23)：47-50．
[24] E.PFENDER. Fundamental studies associated with the plasma spray process. Surface and Coating Technology. 1988(34): 15-23.
[25] Lucas W. Arc surfacing and cladding processes. Welding and Metal Fabrication, 1994,62(2):15-20.
[26]王红英，赵昆．高效等离子堆焊实验系统的建立及工艺研究．焊接，2002，(4)：17-20．
[27] Qu X H. Numerical simulation of feed stock melt-filling in a cylindrical cavity with solidification in powder injection molding. Trans NM-SC, 1998, 8(4):544.
[28]徐滨士，刘世参，刘学蕙．等离子喷涂及堆焊．北京：中国铁道出版社．1996．
[29]韦福水,蒋伯平等.热喷涂技术.北京:机械工业出版社,1985.
[30]Konyashin I.Y.Hysroabraxive Wear Behaviour of High Velocity Oxyfuel Thermally Sprayed WC-M Coatings.Surface and Coatings Technology,1993(63):493-498.
[31]埃里希,路路塞德,阿采丁.利用硬质材料和硬质合金的复合粉末进行等离子弧等焊来提高构件的寿命.国际焊接工程与设备,1999,(1):11-15.
[32]姜焕中.电弧焊及电渣焊.北京:机械工业出版社,1988.
[33]侯清宇,高甲生.铁基合金等离子堆焊研究进展.安徽工业大学学报,2003,20:1.
[34]高荣发等.等离子弧喷焊.北京:机械工业出版社,1979.
[35]郁汉琪,郭健.可编程控制器原理及其应用.北京:中国电力出版社,2004.
[36]宋钧.等离子喷焊工艺的研究.硕士学位论文.天津:天津大学,1996:2-3.
[37]凌幸福,盖翠屏,吴忠萍等.LK-2(3)型微机控制等离子喷焊设备的技术改造以及工艺改进.江西冶金,2000,20(3):31-35.
[38]廖常初.PLC编程及应用.北京:机械工业出版社,2002.
[39]宋建成.可编程序控制器原理及应用.北京:科学出版社,2005:49-52.
[40]吴林、陈善本等.焊接智能化技术.国防工业出版社.2000.8.
[41]陈善本.焊接过程现代化技术.哈尔滨:哈尔滨工业大学出版社,200 1.
[42]张晓坤.可编程控制器原理及应用.西安:西北工业大学出版社,1998.
[43]胡春红.PLC控制等离子弧焊机的研究与等离子云信号的检测.天津大学学报,2002.
[44]SIMENES.STL编程手册.SIMENS.北京.2000.8.
[45]陈克选,李鹤岐,李春旭.铝合金变极性等离子焊阴极清理规律研究甘肃工业大学材料科学与工程学院,甘肃兰州 730050.
[46]熊慰军.碳化物增强Fe07等离子弧喷焊层耐磨粒磨损机理的研究.硕士学位论文.天津:天津大学,1997.
[2] Sare I.R., Mardel J.I., Hill A. J. Wear-resistant metallic and elastomeric materials in the mining and mineral processing industries-an overview. Wear, 2001(250):1-10.
[3]材料耐磨抗蚀及其表面技术概论．北京：机械工业出版社，1986．
[4]孙家枢．金属的磨损．北京：冶金工业出版社，1992：2-4．
[5]邵荷生，张清编．金属的磨损与耐磨材料．北京：机械工业出版社，1988：62-65．
[6]崔信昌编．等离子弧焊接和切割．北京：国防工业出版社，1988：54-65．
[7]冯国昌．焊接技术．凌河汽车制造厂．1996，1：22-23．
[8]王德权，胡毅均，李杰编．阀门用钴基合金及堆焊工艺．2000，5：19
[9]陈俐，潘春旭．耐磨堆焊金属组织分析．武汉交通科技大学学报，1998，(6)：327-329．
[10]刘政军．超硬质相在高温磨损中的行为及抗磨性．焊接学报，1999，(2)：120-125．
[11]徐滨士．表面工程与维修．北京：机械工业出版社，1996：120-131．
[12]磨损失效分析案例编委会．磨损失效分析案例汇集．北京：机械工业出版社，1985：38-66．
[13]李健．等离子弧模具堆焊修复新工艺．锻压技术，1997，4：60-61．
[14]赵唯，柳林．等离子堆焊技术的研究进展．材料导报，2005，5：19．
[15] Schweissen Schneiden Innovations in Welding Technology in 2000.Welding Research Abroad, Jul/Aug,2001,47(7):8-9.
[16]彭补之．国内外热喷焊概况．北京：全国机械工业系统热喷焊，1984．
[17]刘政军．铁基高温耐磨等离子弧喷焊合金及耐磨基理的研究．天津：天津大学，1995．
[18] Gary. R. Heath, John Skora. New materials and process developments for preventative maintenane and repair in cement plants Cement World. 1998(2):360-365.
[19] Wang Xibao, Liu Hua Metal powder thermal behaviour during the plasma transferred-arc surfacing process Surface and Coating Technology 1998(106): 156-161.
[20] Robert. W, Messier Jr. Principles of Welding. John Willy&Soms, INC, 1999.
[21]张德勤，杜则裕，屈朝霞．等离子弧粉末堆焊最佳工艺参数的研究．天津人学学报，1999，6：750-753．
[22] Wang Bibao, Zhang Wenyue. New longitudinal strengthening method for plasma arc powder surfacing coating. Transactions of Tianjin University, 2000(6), 2:157-161.
[23]王红英，程志国，赵昆等．新型等离子弧粉末堆焊机理．焊接学报，2002，4(23)：47-50．
[24] E.PFENDER. Fundamental studies associated with the plasma spray process. Surface and Coating Technology. 1988(34): 15-23.
[25] Lucas W. Arc surfacing and cladding processes. Welding and Metal Fabrication, 1994,62(2):15-20.
[26]王红英，赵昆．高效等离子堆焊实验系统的建立及工艺研究．焊接，2002，(4)：17-20．
[27] Qu X H. Numerical simulation of feed stock melt-filling in a cylindrical cavity with solidification in powder injection molding. Trans NM-SC, 1998, 8(4):544.
[28]徐滨士，刘世参，刘学蕙．等离子喷涂及堆焊．北京：中国铁道出版社．1996．
[29]韦福水,蒋伯平等.热喷涂技术.北京:机械工业出版社,1985.
[30]Konyashin I.Y.Hysroabraxive Wear Behaviour of High Velocity Oxyfuel Thermally Sprayed WC-M Coatings.Surface and Coatings Technology,1993(63):493-498.
[31]埃里希,路路塞德,阿采丁.利用硬质材料和硬质合金的复合粉末进行等离子弧等焊来提高构件的寿命.国际焊接工程与设备,1999,(1):11-15.
[32]姜焕中.电弧焊及电渣焊.北京:机械工业出版社,1988.
[33]侯清宇,高甲生.铁基合金等离子堆焊研究进展.安徽工业大学学报,2003,20:1.
[34]高荣发等.等离子弧喷焊.北京:机械工业出版社,1979.
[35]郁汉琪,郭健.可编程控制器原理及其应用.北京:中国电力出版社,2004.
[36]宋钧.等离子喷焊工艺的研究.硕士学位论文.天津:天津大学,1996:2-3.
[37]凌幸福,盖翠屏,吴忠萍等.LK-2(3)型微机控制等离子喷焊设备的技术改造以及工艺改进.江西冶金,2000,20(3):31-35.
[38]廖常初.PLC编程及应用.北京:机械工业出版社,2002.
[39]宋建成.可编程序控制器原理及应用.北京:科学出版社,2005:49-52.
[40]吴林、陈善本等.焊接智能化技术.国防工业出版社.2000.8.
[41]陈善本.焊接过程现代化技术.哈尔滨:哈尔滨工业大学出版社,200 1.
[42]张晓坤.可编程控制器原理及应用.西安:西北工业大学出版社,1998.
[43]胡春红.PLC控制等离子弧焊机的研究与等离子云信号的检测.天津大学学报,2002.
[44]SIMENES.STL编程手册.SIMENS.北京.2000.8.
[45]陈克选,李鹤岐,李春旭.铝合金变极性等离子焊阴极清理规律研究甘肃工业大学材料科学与工程学院,甘肃兰州 730050.
[46]熊慰军.碳化物增强Fe07等离子弧喷焊层耐磨粒磨损机理的研究.硕士学位论文.天津:天津大学,1997.