不锈钢大罐修补工艺.doc

General 总体要求 Both of weld defects and base metal defects shall be removed by suitable method, to avoid damaging the natural oxide film, most care must be taken. Acid pickling and passivation are necessary if the natural oxide film was damaged. 焊缝和母材的缺陷均应采取适当的方法去除，去除时应尽量减少对金属表面的损伤，对于轻微损伤可进行酸洗钝化处理。 Repair of defective welds 去除和修补不合格焊缝金属 The methods of repairing defective welds shall be as follows: 对于具有缺陷的焊缝采用如下方法进行修补： The welds contour does not meet requirement: 焊缝外形尺寸和形状不符合要求： Grinding with stainless steel wheel , for deep and narrow welds, welding should be used. 用不锈钢砂轮进行修正，并打磨光顺，焊缝过窄过低时，采用手工电弧焊修补。 Undercut咬边： Undercut shall not over 0.5 mm, for undercut over 0.5 mm, welding should be used to repair，and grinding shall be forbidden. 咬边深度不得超过0.5mm，超过0.5mm的，需采用手工电弧焊修补，不允许以磨光母材方法来修补。 Crater弧坑： Repair by SMAW after removal. 未填满的弧坑，清理后用手工电弧焊修补。 Porosity and Slag inclusion 气孔和夹渣： Defects in welds shall be cleared by carbon arc air gouging and grinding , and shall be repaired according to corresponding welding procedure. The surface porosity shall be repaired by SMAW after it is removal. 经检查确认为内部缺陷的部位，应用碳弧气刨清除全部缺陷，然后将氧化物去除干净，最后进行补焊。表面气孔，经对缺陷进行清理后，以手工电弧焊修补。 Lack of penetration未焊透： Removing the defect by gouging and grinding to sound metal and weld, and then use welding to complete the weld. 经检查确认为未焊透的部位应用砂轮机或碳弧气刨清除，然后进行焊补。 Crack裂纹： Where any crack, sound metal one or two inches over both ends of the crack shall be removed. Prior to welding PT shall be carried out to verify complete removal of the defect. 裂纹及其两端各30～50mm范围内彻底铲除，补焊之前应进行渗透探伤（PT）以确保裂纹是否完全铲除。 Requirements of base metal repair 母材缺陷修补的几点要求 1．After removal of base metal defects, if the depth of grinding is less than 2mm, just acid pickle and passivate the surface; if the grinding depth over 2mm, repair by welding, and then acid pickle and passivate the weld surface. 母材缺陷去除后，打磨深度小于2mm，表面直接酸洗钝化处理即可；若打磨深度超过2mm，需进行手工