多因素作用下储气库注采井油管接头气密性分析  

Air Tightness Analysis of Casing Joints in Gas Storage under the Action of Multiple Factors

作　　者：程永钦 刘硕琼 齐奉中 刘慧婷 CHENG Yongqin;LIU Shuoqiong;QI Fengzhong;LIU Huiting(Research Institute of Petroleum Exploration&Development,Beijing 100089,China;Cementing and Completion Research Institute,CNPC Engineering Technology R&D Co.,Ltd.,Beijing 102206,China)

机构地区：[1]中国石油勘探开发研究院,北京100089 [2]中国石油集团工程技术研究院有限公司,固井完井研究所,北京102206

出　　处：《润滑与密封》2022年第7期168-176,共9页Lubrication Engineering

基　　金：国家自然科学基金联合基金项目(U1762212)。

摘　　要：储气库注采井油管接头在服役期间,套管接头处会承受拉、压载荷以及交变压力等,对套管接头气密性产生影响。为研究不同工况下接头主密封面等效应力变化以及分布规律,采用SOLIDWORKS软件和ANSYS软件对特殊螺纹套管接头进行应力分析,确定井口部分为套管串气密性危险点以及主、次密封面过盈量。研究结果表明:为满足特殊螺纹接头气密性及安全性需求,在高内压工况下主、次密封面过盈量应分别为0.05、0.01mm,在低压工况下可适当增加次密封面过盈量,以提高气密性;在实际储气库运行周期中,由于交变载荷的作用,接头主密封面有效密封长度会发生变化,甚至在应力集中区域会发生塑性变形,严重损害接头气密性。因此建议在储气库中使用高屈服强度材料的特殊螺纹接头,以满足不同工况下对接头气密性、安全性要求,同时适当增加次密封面过盈量,使密封面等效应力分布更加均匀。During the service period of the casing joints of the injection-production well in the gas storage,the joints of the casing will be subjected to loads such as tensile and compressive loads and pressure in the alternating pipe,which will affect the air-tightness of the casing.To study the contact stress change and distribution law of the main sealing surface of the joint under different working conditions,SOLIDWORKS software and ANSYS software were used to analyze the stress of the special threaded joint of the casing.The wellhead was determined as the dangerous point of casing string air tightness,and the interference of the main and secondary sealing surfaces was also determined.The results show that in order to meet the air tightness and safety requirements of special threaded joints,the interference of the primary and secondary seal surfaces shall be 0.05 and 0.01 mm respectively under high internal pressure.Under low pressure condition,the interference of the secondary sealing surface can be appropriately increased to improve the air tightness.In the actual operation cycle of the gas storage,due to the alternating load,the effective sealing length of the main sealing surface of the joint is changed,even plastic deformation occurs in the stress concentration area,so as to cause seriously damaging the air tightness of the joint.Therefore,it is recommended to use special threaded joints made of high yield strength materials in the gas storage to meet the air tightness requirements of the joints under different working conditions,and appropriately increase the interference of the secondary sealing surface to make the contact stress distribution of the sealing surface more uniform.

关 键 词：储气库 特殊螺纹接头 过盈量 气密性 交变载荷 

分 类 号：TB42[一般工业技术] TH136[机械工程—机械制造及自动化]