C71500铜镍合金再沸器管子管板焊接  

Tube-to-tubesheet Welding for Reboiler of C71500 Cu-Ni Alloy

作　　者：刘玉祥 齐淑改 商健 Liu Yuxiang;Qi Shugai;Shang Jian

机构地区：[1]森松(江苏)重工有限公司上海分公司,上海201323

出　　处：《中国重型装备》2022年第4期80-84,共5页CHINA HEAVY EQUIPMENT

摘　　要：介绍了铜镍合金 C71500 的物理特性、化学成分及力学性能,通过对 C71500 材料的焊接性进行分析,表明 C71500 合金具有较高的热裂纹敏感性和气孔倾向。再沸器管子管板焊接接头采用 GTAW 方法焊接,焊材选择合金成分与母材成分相当,并含有 Ti、Mn 脱氧元素,S、P 等杂质含量低的焊丝进行焊接试验,焊前及焊接过程中采取了严格的清理等措施,为了保证管子管板根部焊透,采取了φ0. 9 mm 规格细丝打底的工艺,最终结果显示焊缝无裂纹和气孔等缺陷,管子管板接头宏观检验根部及焊缝尺寸满足标准及图纸要求,管子管板拉脱力试验断于管子,拉脱力强度大于换热管标准下限值。此工艺成功应用在产品的焊接中,管子管板接头一次合格率达到了 99% ,取得了良好的效果。The physical properties,chemical composition and mechanical properties of C71500 Cu-Ni alloy are introduced,the weldability of C71500 material is analyzed,the results show that C71500 alloy has high sensitivity to hot crack and porosity tendency. GTAW process is adopted for the tube-to-tubesheet welding joint of reboiler. As to the welding materials,the welding wires with equivalent alloy composition and base matal composition,containing the deoxidation elements such as Ti and Mn and low content of other impurities such as S and P,are selected. Strict cleaning measures have been taken before and during welding. Backing process with fine wire of φ0. 9 mm is adopted in order to ensure the complete penetration of root of tube-to-tubesheet weld. The final results show that there are no cracks and porosity defects in the welds. After macroscopic inspection,the sizes of root and weld of tube-to-tubesheet joint meet the requirements of the standards and drawings. During the pull-out force test for the tube-to-tubesheet joint,the breakage is at the tube side,and the pull-out strength is greater than the lower limit of the heat exchange tube standard. This process has been successfully applied in the welding of products,and the one-time pass rate of tube-to-tubesheet joints reaches 99% ,which shows the good results have been achieved in the practical application.

关 键 词：C71500铜镍合金 合金元素 焊接性 热裂纹 气孔 焊前清理 

分 类 号：TG24[金属学及工艺—铸造]