海洋钻井平台桩腿齿条板与半圆板焊接工艺试验

Research on Welding Procedure of Rack and Semicircular Plate of Offshore Drilling Platform Pile Leg

针对400ft钻井平台桩腿齿条板与半圆板焊接全熔透的新要求,通过试验和不同施焊方法相结合的方式分析了组对间隙和清根与否等因素对Q690E试板接头根部熔深的影响。结果表明,无论采用何种焊接方法,反面清根后施焊,接头熔合状况均良好,且采用实芯焊丝比药芯焊丝接头熔深大。正面气保焊打底,反面不清根采用气保焊施焊,接头熔合不良;而反面采用埋弧焊施焊,接头可实现熔透,但工艺还有待优化,以避免结晶裂纹的产生。

In order to meet the new requirements of full-penetration weld for the rack and semicircular plate of 400 ft offshore drilling platform pile legs, the influence of welding method, root gap and also back gouging or not on the joint penetration of Q690 E steel is investigated. The results indicate that after the second side back gouging, all the joint penetrated is fine regardless of what kind of welding method used, comparing with FCAW, a greater depth of fusion is obtained using GMAW. When the first side is welded by gas shield welding and the second side is welded without back gouging, a joint lack of fusion is get when the second side welded by gas shield welding. But if the second side is welded by SAW, a weld fully penetrated can be realized. But the process should to be optimized in order to avoid crystallization cracks.