球罐的硫化物应力腐蚀及预防措施

含硫化氢的液化气球罐存在着由腐性环境条件而引起的腐蚀破裂。结合球罐的具体情况，对硫化物应力腐蚀形成的特点，影响因素及其预防措施进行了分析和探讨。指出：球罐金属材料的硬度，安装或使用过程中产生的应力，液化石油气中Ｈ２Ｓ的浓度及水分含量的共同作用导致了球罐腐蚀破裂。

Sulfide Stress Cracking of Spherical Tank and its Preventive Measures

The paper analyzes and discusses the cause of sulfide stress cracking (SSC)and its preventive measures , and points out that the interactions among the hardness of tank metal, stresses arisen during installing and operating,H2S concentration and water content of LNG results in SSC of LNG spherical tank. Therefor, three counterrneasures to pvevent the LNG spherical tank from SSC should be taken: (1)selecting the metal with proper hardness to fabricate spherical tank; (2) reducing the stresses of spherical tank if possible ; and adopting heat treatment or hydrostatic test to relief stress; (3) installing sweetening and dehydrat- ing devices.