水下局部干法焊接中的预热技术研究  

Research on Preheating Technology in Underwater Local Dry Welding

作　　者：李志刚[1] 杨炳发[1] 曹军[1] 许威[1] 黄江中[1] 刘阳[2] 

机构地区：[1]海洋石油工程股份有限公司,天津300452 [2]天津大学材料科学与工程学院,天津300072

出　　处：《热加工工艺》2016年第15期200-202,207,共4页Hot Working Technology

摘　　要：针对目前水下局部干法焊接接头淬硬组织多、硬度偏高等问题,本文研究了水下局部干法焊接预热以及后热缓冷的方法,并且针对于各种方法进行了预热温度的计算机仿真模拟。结果表明:电磁感应预热与电弧预热是水下局部干法焊接可以选择的预热方法。Ansys模拟结果表明:在最苛刻的冷却条件下(被焊管道外壁没有任何保温层,且管道内部为水),对于电磁感应预热来说,加热功率为10 k W时,预热温度可以达到89.9℃,完全满足我们的预热要求。并且在工件外表面加一层保温层对减缓焊接热量流失的效果是很好的。对于电弧预热来说,电弧燃烧4 min可以使预热温度达到60℃左右,加保温层后可以达到70℃左右。完全可以将排水罩内的环境烘干,并且将焊枪头部的水烘干。而针对于水下用中频高压电带来的安全问题,本文提出了一种"人电分离"的电磁感应预热模式,后续可以深入研究。Aimed at the problem of hardened tissue, high hardness in the underwater local dry welding joint, the preheating and slow cooling after heating in underwater local dry welding process were studied, and the computer simulation of preheating temperature under the condition of different preheating methods was carried out. The results show that electromagnetic induction preheating and arc preheating can be used for preheating in underwater local dry welding. The results of Ansys simulation show that preheating temperature can reach 89.9℃ with electromagnetic induction preheating utilizing 10 kW preheating power under the severest cooling condition that outer wall of welded pipe has no insulating layer and the internal pipeline is full of water, which fully meets the preheating requirements. And adding a heat insulating layer on the outer surface of the workpiece to slow down the welding heat loss is very good. For arc preheating, four minutes of arc burning can make the preheating temperature reach about 60℃, and the preheating temperature can reach about 70℃ after adding insulating layer, which can completely dry the environment in the drainage cover and the torch head. For the safety problem caused by using the medium frequency, high voltage electric underwater, this paper puts forward a kind of electromagnetic induction preheating mode of human-electricity separation, which can be further studied in the future.

关 键 词：水下局部干法焊接 预热与后热缓冷 ANSYS数值模拟 野人电分离冶 

分 类 号：TG456.5[金属学及工艺—焊接]