薄壁内肋片铜管热型连铸控制系统研究
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摘要
薄壁内肋片铜管传热面积可达到相同规格普通光滑铜管的2到3倍,在制冷和空调等行业中有广泛的应用和巨大的使用量。传统内肋片铜管的加工分为铜管管坯加工和内肋片加工两部分,不仅工艺复杂,而且设备投资大、能源消耗高、成品率低,表面质量也难以得到保证。
热型连铸作为一种全新的近终形加工方法,只要一道工序就可以从铜液中直接连铸出所需形状和尺寸参数的内肋片铜管,是传统加工工艺的革命性变革。
控制固-液界面的位置是热型连铸成功的关键。热型连铸中冷却距离、铸型温度、连铸速度共同决定了固-液界面的位置。计算结果表明从固-液界面到冷却点,铸件温度呈线性分布,可以通过测量铸型外铸件某一点的温度,调节冷却距离控制固-液界面的位置。热电偶测量铸型温度和手动调节冷却距离反应速度慢,效率低,不能满足工业化生产的需要。铜导热系数高,采用红外辐射温度计直接测量铸件温度,实际记录结果证明比热电偶响应速度快,对温度变化趋势反应及时。
引锭管与铜液的连接是顺利连铸出内肋片铜管的重要环节。在铸型设定温度为1080℃时,铸型内实际温度将高于此温度,引锭管管壁很薄,插入部分在连铸之前已经熔化在铸型内,必须保证熔化后的铜液仍能充满内外模之间的空隙,并在内模倒角以上,使上面下来的铜液能顺利进入内模槽内,必须从铸型和引锭管两方面考虑进行改进。
红外辐射温度计输出的电信号,通过A/D模块转化为数字量再输入可编程控制器中进行运算,数据经过处理后作为可编程控制器脉冲输出指令的参数来控制脉冲输出,进而控制步进电机的角位移和转向,从而调节冷却距离。通过冷却距离的调整使测量点的温度达到设定值,实现系统的自动控制。
驱动铜管拉拔辊的直流电机采用调压调速,为了实现调速的稳定性,可使用拨档开关按级调速。调压过程同样可以用可编程控制器实现自动控制,使连铸速度与铸型设定温度和冷却水距离实现联动,使整个系统在较宽的调速范围内实现自动控制。
采用红外辐射温度计、A/D转换器、可编程控制器、步进电机、直流电机
The heat transfer area of thin-walled inner-ribbed copper tube is two to three times of that of common tube which has no inner ribs, so it is widely used in the industries of refrigeration, air-condition etc. The traditional process of inner-ribbed copper tube includes the formations of tube and inner ribs which have the disadvantages of complicated process, huge investment in equipments, high consumption of energy, low finished product rate and difficulty to guarantee surface quality.Heated-mold continuous casting (O.C.C, Ohno continuous casting) is a new near-net-shape processing method and a revolution to traditional machining process. Inner-ribbed copper tube that has the ideal shape and dimensions can be casted directly from copper liquid through only one step.Success of casting thin-walled inner-ribbed copper tube by the vertical O.C.C equipment depends on whether the S+L interface can be kept in position. The location of S+L interface in the mold is determined by cooling distance, mold temperature, casting speed. Calculating results show that the temperature field of casting is linear from S+L interface to cooling point. It is reasonable to control the location of S+L interface by measuring the temperature of one point outside casting mold and adjusting cooling distance. The reaction speed is slow by measuring mold temperature with thermocouple and adjusting cooling distance by hand, so it can not meet the need of industrialization. Copper transfers heat well. The temperature records through computer serial communication show that it has a more rapid reaction speed to measure temperature by infrared thermometer than by thermocouple.It is very important to confirm the dummy ingot tube joint copper liquid very well before casting. When the setting value of mold temperature is 1080℃, the temperature inside mold is higher than it, the thin dummy ingot tube has melted before casting. So the melted copper liquid must fill the slot between outside mold
热型连铸作为一种全新的近终形加工方法,只要一道工序就可以从铜液中直接连铸出所需形状和尺寸参数的内肋片铜管,是传统加工工艺的革命性变革。
控制固-液界面的位置是热型连铸成功的关键。热型连铸中冷却距离、铸型温度、连铸速度共同决定了固-液界面的位置。计算结果表明从固-液界面到冷却点,铸件温度呈线性分布,可以通过测量铸型外铸件某一点的温度,调节冷却距离控制固-液界面的位置。热电偶测量铸型温度和手动调节冷却距离反应速度慢,效率低,不能满足工业化生产的需要。铜导热系数高,采用红外辐射温度计直接测量铸件温度,实际记录结果证明比热电偶响应速度快,对温度变化趋势反应及时。
引锭管与铜液的连接是顺利连铸出内肋片铜管的重要环节。在铸型设定温度为1080℃时,铸型内实际温度将高于此温度,引锭管管壁很薄,插入部分在连铸之前已经熔化在铸型内,必须保证熔化后的铜液仍能充满内外模之间的空隙,并在内模倒角以上,使上面下来的铜液能顺利进入内模槽内,必须从铸型和引锭管两方面考虑进行改进。
红外辐射温度计输出的电信号,通过A/D模块转化为数字量再输入可编程控制器中进行运算,数据经过处理后作为可编程控制器脉冲输出指令的参数来控制脉冲输出,进而控制步进电机的角位移和转向,从而调节冷却距离。通过冷却距离的调整使测量点的温度达到设定值,实现系统的自动控制。
驱动铜管拉拔辊的直流电机采用调压调速,为了实现调速的稳定性,可使用拨档开关按级调速。调压过程同样可以用可编程控制器实现自动控制,使连铸速度与铸型设定温度和冷却水距离实现联动,使整个系统在较宽的调速范围内实现自动控制。
采用红外辐射温度计、A/D转换器、可编程控制器、步进电机、直流电机
The heat transfer area of thin-walled inner-ribbed copper tube is two to three times of that of common tube which has no inner ribs, so it is widely used in the industries of refrigeration, air-condition etc. The traditional process of inner-ribbed copper tube includes the formations of tube and inner ribs which have the disadvantages of complicated process, huge investment in equipments, high consumption of energy, low finished product rate and difficulty to guarantee surface quality.Heated-mold continuous casting (O.C.C, Ohno continuous casting) is a new near-net-shape processing method and a revolution to traditional machining process. Inner-ribbed copper tube that has the ideal shape and dimensions can be casted directly from copper liquid through only one step.Success of casting thin-walled inner-ribbed copper tube by the vertical O.C.C equipment depends on whether the S+L interface can be kept in position. The location of S+L interface in the mold is determined by cooling distance, mold temperature, casting speed. Calculating results show that the temperature field of casting is linear from S+L interface to cooling point. It is reasonable to control the location of S+L interface by measuring the temperature of one point outside casting mold and adjusting cooling distance. The reaction speed is slow by measuring mold temperature with thermocouple and adjusting cooling distance by hand, so it can not meet the need of industrialization. Copper transfers heat well. The temperature records through computer serial communication show that it has a more rapid reaction speed to measure temperature by infrared thermometer than by thermocouple.It is very important to confirm the dummy ingot tube joint copper liquid very well before casting. When the setting value of mold temperature is 1080℃, the temperature inside mold is higher than it, the thin dummy ingot tube has melted before casting. So the melted copper liquid must fill the slot between outside mold
引文
[1] 倪德斌,陈大元,邓亚军.国内外螺旋肋片省煤器技术分析及应用.四川电力技术,1998(5):1～5
[2] 覃耕等.换热器实用技术问题.第1版.北京:煤炭工业出版社,1991
[3] 青岛空调器厂.从湍流管应用谈空调器节能(会议资料),1990.8
[4] 刘兴仁,李兵,杨奇辉.肋片管省煤器的应用与设计.四川电力技术,1999(4):37～41
[5] 柳大敏.国内外空调制冷铜管的技术发展.上海有色金属,1997,18(4):183～190
[6] 吴浙民.上引法生产设备的设计研究.有色金属再生与利用,2004(11):12～13
[7] 汤勇,陈澄洲,张发英.内螺纹翅片铜管高速旋压拉伸成形的研究.工具技术,1997,31:19～22
[8] 江正义,刘相华,谢春蓉等.高效传热内直筋管的开发与应用.辽宁冶金,1995,(1):55～57
[9] Ohno, H. Soda. Proceedings of F. Weinberg Int. Symposiumon Solidification Processing, The Metallurgical Society of CIM, 20, 1990:215～228
[10] A. Ohno. Casting of Near Net Shape Products. The Metallurgical Society, 1988:177～184
[11] 大野笃美,金属的凝固理论、实践及应用,机械工业出版社,1983
[12] 黎沃光.热型连续铸造法的原理及应用.铸造,1996,(12):39～44
[13] H. Soda, F. Chabchoub, et al. Experimental Study of the Horizontal Ohno Continuous Casting System, Canadian Metallurgical Quarterly, 1992, 31(3):231～239
[14] Soda H, Lchinose A, Motoyasu Getal. A New Fabrication Method for the Casting of Cored Materials. Cast Metals. 1992, 5(2):95～102
[15] A. Ohno. Continuous Casting of Single Crystal Ingots by the O. C. C Process, J. of Metals,1986, 38(1):14～16
[16] Shimizu, H. Yamazaki, et al. Proceedings of the Int. Symposiumon Development and Applications of Ceramics and New Metal Alloys. 32nd Annual Conference of Metallurgists of CIM, Quebec City, 1993:541～549
[17] G. Motoyasu, A. Ohno, et al. Proceedings of the Int. Symposium Development and Applications of Ceramics and New Metal Alloys. 33rd Annual Conference of Metallurgists of CIM, Toronto, 1994:20～25
[18] 山崎裕之,大野笃美,清水亨,加熱铸型用異型断面铸塊连殼铸造,日本金属学会志,1994,58(1):37～42
[19] 山崎裕之,大野笃美,清水亨.加熟铸型式连殼铸造法制造材性质应用,日本金属学会志,1994,58(9):1061～1066
[20] 黎沃光.热型连续铸造法包铸光学纤维.特种铸造及有色合金,1997(2):18～21
[21] Soda H, Mclean A, Shen J. Development of Net-Shape Cast Aluminum Alloy Wires and Their Solidification Structures. Jounal of Materials Science, 1997, 32:1841～ 1847
[22] Motoyasu G, Soda H, McleansA, Shimizu T. Al-CuAl_2 Eutectic Structure in Unidirectionally Solidified Rods by the Continuous Casting Process. Journal of Materials Science Letters. 1997(16):566～588
[23] 大野笃美.O.C.C Process 新素材开发.轻金属,1989,30(10):735～740
[24] 赵锋.Bfe30-1-1白铜管坯的热型连铸:[硕士学位论文].广东工业大学材料与能源学院,2002
[25] 邱阿瑞,孙旭东.实用电动机控制.第一版.北京:人民邮电出版社,1998.89～93
[26] 李铁才.电机控制技术.第一版.哈尔滨:哈尔滨工业大学出版社,2000.7～10
[27] H. Soda, G. Motoyasu, etal, Canadian metallurgical Quarterly, 1994, 33(2):89～98
[28] H. soda, F. Chabchoub, etal. Cast Metals, 1991, 4(1):16～23
[29] 黎沃光等.铅锡合金的热型连铸,铸造技术,1997.5:42～44
[30] 上海自动化仪表三厂,光导纤维红外辐射温度计使用说明书,1991
[31] 范逸之,陈立元.Visual Basic与Rs-232串行通信控制.第一版.北京:清华大学出版社,2002.54
[32] 高钦和.可编程控制器应用技术与设计实例.第一版.北京:人民邮电出版社,2004.131～137
[33] 钟肇新,彭侃.可编程控制器原理及应用.第二版.广州:华南理工大学出版社,2003.5～20
[34] 钟肇新,范建东.可编程控制器原理及应用.第三版.广州:华南理工大学出版社,2003.152～157
[35] 广州旺达自动化仪表有限公司编.FX2N编程手册
[2] 覃耕等.换热器实用技术问题.第1版.北京:煤炭工业出版社,1991
[3] 青岛空调器厂.从湍流管应用谈空调器节能(会议资料),1990.8
[4] 刘兴仁,李兵,杨奇辉.肋片管省煤器的应用与设计.四川电力技术,1999(4):37～41
[5] 柳大敏.国内外空调制冷铜管的技术发展.上海有色金属,1997,18(4):183～190
[6] 吴浙民.上引法生产设备的设计研究.有色金属再生与利用,2004(11):12～13
[7] 汤勇,陈澄洲,张发英.内螺纹翅片铜管高速旋压拉伸成形的研究.工具技术,1997,31:19～22
[8] 江正义,刘相华,谢春蓉等.高效传热内直筋管的开发与应用.辽宁冶金,1995,(1):55～57
[9] Ohno, H. Soda. Proceedings of F. Weinberg Int. Symposiumon Solidification Processing, The Metallurgical Society of CIM, 20, 1990:215～228
[10] A. Ohno. Casting of Near Net Shape Products. The Metallurgical Society, 1988:177～184
[11] 大野笃美,金属的凝固理论、实践及应用,机械工业出版社,1983
[12] 黎沃光.热型连续铸造法的原理及应用.铸造,1996,(12):39～44
[13] H. Soda, F. Chabchoub, et al. Experimental Study of the Horizontal Ohno Continuous Casting System, Canadian Metallurgical Quarterly, 1992, 31(3):231～239
[14] Soda H, Lchinose A, Motoyasu Getal. A New Fabrication Method for the Casting of Cored Materials. Cast Metals. 1992, 5(2):95～102
[15] A. Ohno. Continuous Casting of Single Crystal Ingots by the O. C. C Process, J. of Metals,1986, 38(1):14～16
[16] Shimizu, H. Yamazaki, et al. Proceedings of the Int. Symposiumon Development and Applications of Ceramics and New Metal Alloys. 32nd Annual Conference of Metallurgists of CIM, Quebec City, 1993:541～549
[17] G. Motoyasu, A. Ohno, et al. Proceedings of the Int. Symposium Development and Applications of Ceramics and New Metal Alloys. 33rd Annual Conference of Metallurgists of CIM, Toronto, 1994:20～25
[18] 山崎裕之,大野笃美,清水亨,加熱铸型用異型断面铸塊连殼铸造,日本金属学会志,1994,58(1):37～42
[19] 山崎裕之,大野笃美,清水亨.加熟铸型式连殼铸造法制造材性质应用,日本金属学会志,1994,58(9):1061～1066
[20] 黎沃光.热型连续铸造法包铸光学纤维.特种铸造及有色合金,1997(2):18～21
[21] Soda H, Mclean A, Shen J. Development of Net-Shape Cast Aluminum Alloy Wires and Their Solidification Structures. Jounal of Materials Science, 1997, 32:1841～ 1847
[22] Motoyasu G, Soda H, McleansA, Shimizu T. Al-CuAl_2 Eutectic Structure in Unidirectionally Solidified Rods by the Continuous Casting Process. Journal of Materials Science Letters. 1997(16):566～588
[23] 大野笃美.O.C.C Process 新素材开发.轻金属,1989,30(10):735～740
[24] 赵锋.Bfe30-1-1白铜管坯的热型连铸:[硕士学位论文].广东工业大学材料与能源学院,2002
[25] 邱阿瑞,孙旭东.实用电动机控制.第一版.北京:人民邮电出版社,1998.89～93
[26] 李铁才.电机控制技术.第一版.哈尔滨:哈尔滨工业大学出版社,2000.7～10
[27] H. Soda, G. Motoyasu, etal, Canadian metallurgical Quarterly, 1994, 33(2):89～98
[28] H. soda, F. Chabchoub, etal. Cast Metals, 1991, 4(1):16～23
[29] 黎沃光等.铅锡合金的热型连铸,铸造技术,1997.5:42～44
[30] 上海自动化仪表三厂,光导纤维红外辐射温度计使用说明书,1991
[31] 范逸之,陈立元.Visual Basic与Rs-232串行通信控制.第一版.北京:清华大学出版社,2002.54
[32] 高钦和.可编程控制器应用技术与设计实例.第一版.北京:人民邮电出版社,2004.131～137
[33] 钟肇新,彭侃.可编程控制器原理及应用.第二版.广州:华南理工大学出版社,2003.5～20
[34] 钟肇新,范建东.可编程控制器原理及应用.第三版.广州:华南理工大学出版社,2003.152～157
[35] 广州旺达自动化仪表有限公司编.FX2N编程手册