井口装置材料抗应力腐蚀的可靠性评价

The Evaluation on the Reliability of Wellhead Equipment Materials in Resisting Stress Corrosion

对井口装置材料抗应力腐蚀的发生条件及腐蚀机理进行了分析,并依据应力-强度干涉理论对材料的抗应力腐蚀性能进行可靠性评价。运用应力与强度呈正态分布时的可靠度计算公式,计算了不同应力状态下材料的可靠度,进而求得可靠性意义下的安全系数,从而提高井口装置材料的可靠性,可保证设备的安全运行。试验研究证明了此方法的可行性。

This paper first analyzes the occurrence conditions and corrosion mechanism of stress corrosion about wellhead equipment materials. Meanwhile, the material properties for resisting stress corrosion are evaluated from the perspective of reliability according to the stress and strength interference theory. The reliability calculation formula in the normal distribution of the stress and strength has bee used to calculate the material reliability under the different stress, together with the safety factor under the reliability. Then the reliability of wellhead equipment material can be promoted so as to guarantee the safe operation of equipments. At last, experimental study has proved its flexibility.