高强度HY级抽油杆在含硫工况下的环境敏感断裂评价

Environment-sensitive fracture evaluation of high-strength HY-grade sucker rods under sulfur working conditions

陈昂 于会永 田刚 李皓 张海鑫 曾德智2

中国石油新疆油田公司工程技术研究院，新疆 克拉玛依 834000 西南石油大学油气藏地质及开发工程国家重点实室，四川 成都 610500 安科工程技术研究院（北京）有限公司，北京 100089

Engineering Technology Research Institute, Xinjiang Oilfield Company, PetroChina, Karamay 834000, China State Key Laboratory of Oil & Gas Reservoir Geology and Exploration, Southwest Petroleum University, Chengdu 610500, China Safetech Research Institute, Beijing 100089, China

文中对HY级抽油杆的化学成分和基本力学性能进行了测试，并采用慢应变速率拉伸（SSRT）实验评价了HY级抽油杆在不同H2S环境中的断裂敏感性。结果表明：当H2S质量浓度从0提高到3 618 mg/L（饱和）时，HY级抽油杆的抗拉强度下降了2.5%，氢脆指数达到53.3%，强塑积下降了54.3%；随着H2S质量浓度升高，抗拉强度和强塑积逐渐减小，氢脆指数逐渐增加，材料由韧性断裂向韧脆性断裂转变。研究认为，在H2S环境中，HY级抽油杆具有较强的环境断裂敏感性，SSC（硫化物应力开裂）机制是氢脆为主和阳极溶解为辅共同作用的结果。

In order to evaluate the sensitive fractures of the high-strength HY-grade sucker rod under sulfur working conditions，the chemical compositions and basic mechanical properties of sucker rod were tested, and the fracture-sensitivity of sucker rod in H2S environment was evaluated by slow strain rate tensile test (SSRT). The results show that when the concentration of H2S was changed from 0 to the saturation concentration(3,618 mg/L), the tensile strength(TS) and the product of tensile strength and elongation(TS×EL) were respectively decreased by 2.5% and 54.3% and the hydrogen embrittlement index(HEI) reached 53.3%. With the increase in the H2S concentration, the TS and the TS×EL decreased and the HEI increased. The fractures of the material were shifted from ductile fracture to ductile-brittle fracture. In an acidic H2S environment, the HY-grade sucker rod shows the high environment-fracture-sensitivity and the SSCC(sulfide stress corrosion cracking) of the sucker rod is the combined consequence of the dominant hydrogen embrittlement effect and the secondary anodic dissolution effect.

10.6056/dkyqt201806029