weldite白硅铝钠石weldv.焊接；使结合n.焊接；焊缝weld metal buildup surface金属堆焊表面welder rs lifting platform焊工升降台Welding heat affected area焊接热影响区weld coarse crystal region焊接粗晶区welded stayed construction焊接的支撑结构welding technology measure焊接工艺措施welding stainless electrode不锈电焊条welding on dissimilar steel异质钢焊接weld piping branch junction焊制三通welding procedures of shell简节焊接工艺措施