重载铁路75kg·m~(-1)钢轨铝热焊接头力学性能试验分析
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摘要
某重载铁路线路采用铝热焊技术实现钢轨现场焊接,为分析评价铝热焊接头的力学性能,对现场取样的焊接钢轨进行一系列室内力学试验,试验结果表明:部分试样轨头受压静弯试验不满足荷载力要求,所有试样最大挠度均低于规范限值;部分试样疲劳加载次数未达到200万次要求的;所有试样的冲击吸收功远低于规范要求。该重载铁路75 kg·m-1钢轨铝热焊接头的力学性能不满足规范要求,需要对焊剂、焊接设备以及焊接工艺进行改进,以满足重载铁路高强度钢轨对铝热焊接头力学性能的要求。
Thermit welding is applied in the heavy haul railway line to realize site welding of rails. In order to eval-uate mechanical properties of the thermit welded joint, this study carried out a series of laboratory tests for the sitesamples. The test results show as follows: Some of the samples do not meet the requirements of load in bendingtest; The maximum deflection of each testing sample is lower than limit; The number of fatigue loading cycles ofsome samples are less than the limit of 2×106; The impact absorbing energy of all samples do not meet the standardrequirements. In general, mechanical properties of thermit welded joint of 75 kg·m-1rail do not meet the currentrequirements. It is necessary to make improvements in welding flux, equipment and process to enhance the perfor-mance of thermit welded joint and to meet the requirements as well.
Thermit welding is applied in the heavy haul railway line to realize site welding of rails. In order to eval-uate mechanical properties of the thermit welded joint, this study carried out a series of laboratory tests for the sitesamples. The test results show as follows: Some of the samples do not meet the requirements of load in bendingtest; The maximum deflection of each testing sample is lower than limit; The number of fatigue loading cycles ofsome samples are less than the limit of 2×106; The impact absorbing energy of all samples do not meet the standardrequirements. In general, mechanical properties of thermit welded joint of 75 kg·m-1rail do not meet the currentrequirements. It is necessary to make improvements in welding flux, equipment and process to enhance the perfor-mance of thermit welded joint and to meet the requirements as well.
引文
[1]王元清,周晖,奚望,等.铁路钢轨铝热焊接接头的低温力学性能试验[J].焊接学报,2010,31(7):13-16,21.
[2]车军,郑韶先,苏程,等.国内钢轨焊接的现状及发展趋势[J].焊接,2011(10):33-35.
[3]刘正文,丁韦,李力,等.重载线路铝热焊接头轨头下部夹杂缺陷分析[J].焊接技术,2012,41(9):46-48.
[4]李金华,李力,丁韦,等.75 kg·m-1钢轨铝热焊接头断裂失效研究[J].铁道建筑,2011(11):102-105.
[5]KRISTAN J.Advcmces in rail welding[J].Railway Track and Structure,2004,100(2):15-17.
[6]MUTTON P J,ALVAREZ E F.Failure modes in aluminothermic rail welds under high axle load conditions[J].Engineering Fail-ure Analysis,2004,11(2):151-166.
[7]贺颂,徐伟人.LR1200焊轨车PG4焊接工艺调试[J].上海铁道科技,2013(1):38-39.
[8]王少锋,许玉德,周宇,等.基于临界平面法的钢轨裂纹萌生寿命预测模型研究[J].华东交通大学学报,2011,28(5):77-82.
[9]周清跃,张建峰,郭战伟,等.重载铁路钢轨的伤损及预防对策研究[J].中国铁道科学,2010,31(1):27-31.
[10]崔成林,高松福,迟俊杰,等.国内外钢轨铝热焊接技术研究现状和发展[J].铁道建筑,2009(6):96-100.
[11]中华人民共和国铁道部.TB/T 1632.1-2005钢轨焊接第1部分:通用技术条件[S].北京:中国铁道出版社,2005.
[12]中华人民共和国铁道部.TB/T 1632.3-2005钢轨焊接第3部分:铝热焊接[S].北京:中国铁道出版社,2005.
[2]车军,郑韶先,苏程,等.国内钢轨焊接的现状及发展趋势[J].焊接,2011(10):33-35.
[3]刘正文,丁韦,李力,等.重载线路铝热焊接头轨头下部夹杂缺陷分析[J].焊接技术,2012,41(9):46-48.
[4]李金华,李力,丁韦,等.75 kg·m-1钢轨铝热焊接头断裂失效研究[J].铁道建筑,2011(11):102-105.
[5]KRISTAN J.Advcmces in rail welding[J].Railway Track and Structure,2004,100(2):15-17.
[6]MUTTON P J,ALVAREZ E F.Failure modes in aluminothermic rail welds under high axle load conditions[J].Engineering Fail-ure Analysis,2004,11(2):151-166.
[7]贺颂,徐伟人.LR1200焊轨车PG4焊接工艺调试[J].上海铁道科技,2013(1):38-39.
[8]王少锋,许玉德,周宇,等.基于临界平面法的钢轨裂纹萌生寿命预测模型研究[J].华东交通大学学报,2011,28(5):77-82.
[9]周清跃,张建峰,郭战伟,等.重载铁路钢轨的伤损及预防对策研究[J].中国铁道科学,2010,31(1):27-31.
[10]崔成林,高松福,迟俊杰,等.国内外钢轨铝热焊接技术研究现状和发展[J].铁道建筑,2009(6):96-100.
[11]中华人民共和国铁道部.TB/T 1632.1-2005钢轨焊接第1部分:通用技术条件[S].北京:中国铁道出版社,2005.
[12]中华人民共和国铁道部.TB/T 1632.3-2005钢轨焊接第3部分:铝热焊接[S].北京:中国铁道出版社,2005.