摘要
针对海上热采用排气阀在高温高压下存在液控管线损坏导致无法正常开启关闭的问题,设计了常开式高温排气阀。常开式高温排气阀采用全金属密封,保证在常温到350℃高低温交变工况下密封可靠性,并通过高低温室内试验进行验证;通过常压开启、加压关闭的方式避免井下工具和管线长期高温承压,提高了排气阀启闭的可靠性;对开启和关闭2个状态下的阀体进行了受力分析,利用Hertz接触理论建立了阀体-下接头的球头-锥面接触力学理论模型,通过对球面半径、锥面锥角和液控端压力敏感性分析,优化了地面关闭压力和密封压力等工作性能参数,保证在应急状态下关闭的可靠性。通过理论模型优化设计,球面半径8.2 mm、锥面锥角4.6°时具备最佳的密封性能,并得到了不同环空压力下的关闭压力图版;常开式高温排气阀经过高低温试验,表明常开式高温排气阀开启关闭动作灵活可靠,在60~350℃下都具有可靠的密封性能,能够满足海上热采井长期注汽-采油需要。常开式高温排气阀适合海上热采井常开高低温交变工况下长期使用,建议在海上3轮次吞吐井及驱替井推广应用。
The vent valve for offshore thermal recovery cannot be opened or closed normally under high temperature and high pressure(HTHP)conditions due to the damage of hydraulic control pipeline.To solve this problem,a normally open high-temperature vent valve was designed.It adopts all-metal sealing to ensure its sealing reliability under the high-low temperature alternating working condition ranging from normal temperature to 350℃,which was verified by high-low temperature laboratory tests.Its opening at atmospheric pressure and closing at high pressure prevent the downhole tools and pipeline from long-term exposure to HTHP,thus improving its opening/closing reliability.The force analysis of the valve was conducted in the states of opening and closing.Based on the Hertz contact theory,a theoretical model of globe-cone contact mechanics between valve and lower joint was established.Based on the sensitivity analysis of spherical radius,cone angle and hydraulic control pressure,the working performance parameters of surface closing pressure and sealing pressure were optimized to ensure its closing liability in case of emergency.The optimization design of theoretical model shows that it has the best sealing performance at spherical radius of 8.2 mm and cone angle of 4.6°.In addition,the closing pressure charts under different annular pressures were obtained.The high-low temperature tests indicate that the normally open high-temperature vent valve can be opened and closed flexibly and reliably,and it has reliable sealing performance at 60~350℃,which meets the requirements of long-term steam injection and oil production of offshore thermal recovery wells.The normally open high-temperature vent valve is suitable for long-term use in offshore thermal recovery wells under normally open and high-low temperature alternating working conditions.It is recommended to be applied in offshore three-cycle huff-and-puff wells and displacement wells.
作者
孙永涛
胡厚猛
白健华
孙玉豹
马增华
顾启林
Sun Yongtao;Hu Houmeng;Bai Jianhua;Sun Yubao;Ma Zenghua;Gu Qilin(CNOOC(China)Limited;Tianjin Branch of CNOOC(China)Limited)
出处
《石油机械》
北大核心
2022年第12期66-72,共7页
China Petroleum Machinery
基金
天津市科技领军企业认定及重大项目“海上中深层特稠油热采关键技术研究及应用”(20YDLZCG00190)的部分研究成果。
关键词
海上热采
常开式高温排气阀
金属滑动密封
球头-锥面密封
接触应力
室内高温试验
offshore thermal recovery
normally open high-temperature vent valve
metal sliding seal
globe-cone seal
contact stress
laboratory high-temperature test
