The waterproof layer of the lap joint should stick (welding) firm, tight sealing, no distortion, fold, curling and blister defects.
卷材屋顶防水层的搭接缝应粘(焊)结牢固，密封精密，不得有扭曲、皱折、翘边和起泡等缺陷。
2
Welding and allied processes. resistance spot, projection and seam welded lap joints. classification of defects with explanatory comments.
焊接和有关技术。电阻点焊凸焊或缝焊搭接接头。带解释的缺陷分类。
3
Current, welding speed, and pressure are the factors which can influence the welding quality of narrow lapwelding machine during the galvanizing unit production.