防止硫化氢应力腐蚀失效的EFC准则应用及验证

CRITERIA TO AVOID SULPHIDE STRESS CRACKING PROVIDED BY EFC AND ITS VERIFICATION

根据欧洲腐蚀协会 (EFC)关于防止SSC的失效准则 ,通过恒载拉伸及三点弯曲试验确定了国产低合金高强钢WH6 10D2的适用环境为含H2 S 10 0× 10 -6的酸性溶液 .同时进行了模拟压力容器现场工况条件的焊板系列试验 ,对EFC准则进行了有效性验证 .结果表明EFC准则有很好的应用价值 .

In accordance with the criteria to avoid SSC provided by European Federation of Corrosion (EFC),the constant tensile load testing and three-point bend testing for low alloy and high strength steel WH610D2 were carried out and an acceptable environment of H 2S-containing 100×10 -6 solution was identified.To verify the validity of the EFC criteria,a series of welded plate testing simulating the anticipated field conditions of pressure vessels was conducted and the results show that the EFC criteria can be used well in services.The testing plate used includes both welded state and heat-treated state.The working stresses were produced by loading with bolts.The welding residual stresses and working stresses were measured by PSM-2F X-ray analyzer.Three sets of testing plate were conducted respectively in three different H 2S content solutions:1500×10 -6 ,500×10 -6 ,100×10 -6 .Upon termination of exposure after one and two months,the testing plates were examined to determine whether cracks occurred.The examinations showed that,on the plates in the solutions of H 2S content being 1500 ×10 -6 and 500×10 -6 ,many cracks occurred; and on the plate in the solution of H 2S content being 100×10 -6 ,no crack was examined.So the results show that the EFC criteria can be used well in services.