扬子30万 t/年乙烯工程球罐的焊接

Spherical Tank Welding of 300,000t/year Ethylene Plant in Yangzi

本文针时扬子30万t/年乙烯物料罐区32台国产或引进球罐的焊接施工,介绍了低合金高强度钢SPV36和SPV50Q球罐用材的理化性能和焊接特性;焊条选择、焊接坡口及工艺规范等方面的工艺特点;各类球罐的焊接工艺评定,焊工考试、焊接施工管理及检验。应用近年采的焊接研究成果,重点分析了材料碳当量、预热温度和扩散氢含量的关系;冷却速度和接头金相组织的关系。通过焊接一次合格率的对比,介绍了球罐施工中“散装法”、“带装法”和“大片组装法”的优缺点。

The physical and chemical properties of low alloy high strength SPV36 and SPV50Q steel sed for 32 spherical welding tanks made in China or introduced from over seas in the Yangzi 300,000t/year ethylene storage site are described. The selecting of electrod kinds and weld bcvel types, the process standerds, the process appraisal, the examination of the welders, the manage- ment of welding operation and the detecting methods of welding are all described in this article. The relationship between the carbon equivalent of material, the preheating temperature and the diffused hydrogen contents, as well as the relationship between cooling rate and micro-struc- ture of joints are mainly analysised by applying the research results got in recent years. The advan- tages and disadvantages of 'Bulk-installation'. 'Band-installation' and 'largnsegment-installa- tion' methods for spherical tanks building are also compared.