海上自喷油井关井井口压力预测方法

油井生产过程中紧急关井的井口压力是合理选择井口设备以及管线的重要依据,但目前缺乏该方面的理论计算方法。分析认为水击压力主要受关井瞬间流体流速、压力波传播速度和流体密度等3个因素影响,建立了水击压力及由井底压力恢复引起的井口压力变化的计算方法;综合考虑水击压力和关井压力恢复的影响,研究了生产油井紧急关井情况下井口压力的变化趋势。研究表明:中高渗地层的井口压力随着时间的增加而增大,关井时间越长,井口压力越大;低渗地层的井口压力会在短时间内突然增加。 

Wellhead Pressure Prediction Method during Well Shut-in for Offshore Flowing Oil Wells

Wellhead pressure in case of any emergency well shut-in is a very important parameter in wellhead equipment and pipeline selection,but theoretical calculation method of well head pressure is not available yet.Water hammer pressure is mainly affected by fluid rate,pressure wave propagation velocity and fluid density.The calculation method of wellhead pressure resulting from water hammer pressure and bottom pressure buildup is established.Considering the influence of water hammer pressure and shut-in pressure buildup,the change of wellhead pressure in case of emergency well shut-in is studied.The study shows that wellhead pressure in medium to high permeability reservoir would increase vs.time.The longer the well shut-in time,the higher the wellhead pressure would be.The wellhead pressure for production in low permeability reservior may increase in a sudden.