VLEC B型舱5Ni钢免预热焊接工艺

Non-Preheating Welding Procedure of 5Ni Steel for Type B Tank of VLEC

针对原5Ni钢焊条焊前需要对钢板进行预热、生产效率相对较低的情况,在99000 m3超大型乙烷运输船(Very Large Ethane Carrier,VLEC)B型舱建造过程中采用OK 92.55焊条和NI-C70S焊条进行5Ni钢焊接。经焊条性能、抗裂性和焊接工艺等试验研究,结果表明:两种焊条性能均满足规范要求,且抗裂性良好;在焊接参数处于合理范围内时,两种焊条均可在免预热钢板的情况下满足实船建造5Ni钢焊接接头的性能要求。

In view of the situation of original 5Ni steel welding rod that the steel plate needs to be preheated before welding and the production efficiency is relatively low, OK 92.55 welding rod and NI-C70S welding rod are used for the 5Ni steel welding during the construction of 99 000 m~3 Type B tank of Very Large Ethane Carrier(VLEC). After the test research on welding rod performance, cracking resistance, and welding procedure, the results show that: the performance of two kinds of welding rod meet the requirements of the specification, and the cracking resistance is good;when the welding parameters are in a reasonable range, two kinds of welding rod can meet the performance requirements of 5Ni steel welding joints in real ship construction without preheating steel plates.