X90螺旋埋弧焊管抗硫化氢性能的研究

Study on The Performance of Anti Hydrogen Sulfide of X90 SSAW Pipe

对X90螺旋埋弧焊管进行氢致开裂(HIC)和硫化氢应力腐蚀开裂(SSCC)实验研究,结果表明:X90螺旋埋弧焊管管母比焊缝抗HIC的能力差,高位错密度的组织和高硬度是导致发生HIC开裂的主要原因。在72%最下规定屈服强度应力下进行SSCC实验,其中两个试样断裂失效,主要是由于断裂部位存在夹杂物或高的残余应力,以及粒状贝氏体(B粒)组织的存在引起硬度波动偏高而导致应力腐蚀断裂。电化学极化实验和交流阻抗测试也进一步证实了管母比焊缝更容易被腐蚀。

The Hydrogen Induced Cracking （HIC） test and Sulfide Stress Corrosion Cracking （SSCC） test of the X90 spiral submerged arc welded pipe was studied. The test results show that the tube＇s anti HIC capability are much lower than weld seam. The tube＇ s hydrogen induced cracking is mainly caused by the high structure of dislocation density and high hardness. Under 72% SMYS stress （SSCC） test, two specimen are failed with fracture, mainly due to the presence of inclusions and high residual stress in HAZ or tube, and the Bainite organization＇s existence caused high hardness fluctuation, which leads to stress corrosion cracking. Electrochemical polarization test and impedance detection test also confirmed that the welded joint＇ s anti corrosion performance is better than tube.