天湖水电站压力钢管环口现场焊接与热处理

Pipe Orifice Welding and Heat Treatment of Steel Penstock on the Spot of the Tianhu Hydropower Station

天湖水电站压力钢管内径1m。壁厚28～46mm,钢材主要为16Mn钢,工厂制作每节长度约10m,环口加工为U,V型组合坡口,运至现场采用焊前预热,手工氩气弧焊封底与手工电弧焊填充盖面、焊后热处理的组合工艺组装焊接,环口焊接的工艺和质量是钢管安装工程的关键之一。

The material of the steel penstock of the Tianhu hydropower station is mainly 16 Mn steel, it's 1 m of inner diameter and 28～46mm of thickness. Each length of penstock made by factory is about 10m long. The pipe orifice is processed into U or V type of chamfer. The penstocks were carried to main work spots, assembled and welded which adopted a series of complicate techniques shch as pre—heat before welding, argon welding and sealing bottom by hand, are welding and back filling surface by hand, and heat treatment after welding. The techniques and quality of pipe orifice welding are one of the keys for installation of penstock.