一、引言随着海上石油开采发展的需要,建造我国沿海所需的各种海上石油平台的任务日益增多。海上采油平台是一座庞大而复杂的焊接建筑物,由于海上环境条件恶劣,长年累月承受低频交变应力,它比正常应力高8～12倍。平台的关键部位如桩脚支架、管架节点、厚板结构焊点等处将萌生疲劳破坏和层状撕裂破坏,因而其关键部位必须使用抗层撕裂性能好的Z向钢。我国已将Z向钢试制成功,并开展了有关的研究分析工作。我们在余宗森教授的指导下,也开展了一部分试验工作。据资料介绍,当钢材中氢含量超过2ppm时,会诱发和促进层状撕裂破坏的作用,钢 I. INTRODUCTION With the development of offshore oil exploitation, the task of building a variety of offshore oil platforms required for coastal areas in our country is increasing day by day. Offshore production platform is a large and complex welded buildings, due to harsh offshore conditions, withstand low frequency alternating stress over many years, it is 8 to 12 times higher than the normal stress. The key parts of the platform, such as pile foot support, pipe rack joints, thick plate joints and other places will initiate fatigue damage and layered tearing failure, so its key parts must use good anti-layer tear Z-steel. Z steel has been successfully trial-produced in our country and carried out relevant research and analysis work. Under the guidance of Professor Yu Zongsen, we also carried out a part of the experimental work. According to the information, when the hydrogen content in the steel exceeds 2ppm, it will induce and promote the role of lamellar tearing and cracking. Steel