水平井压后关井扩散压力时间优化

Time Optimization by Diffusion Pressure after Fracture for Horizontal Well

水平井多级压裂对于提高油层产能和解决低渗透油层难动用储量的开采具有重要意义。根据W35区块7口井和WT43区块6口井进行压后关井扩散压力分析和总结发现,关井时间与压力下降速率、见油时间和产量有关。利用地层径向流开始时间的理论公式对垣平1区块资料进行计算认为,当压后流动时间达到3倍的地层径向流开始时间后,为最佳的压后关井恢复时间。渗透率越高,需要关井时间越短;渗透率越低,需要关井时间越长。通过计算地层径向流开始时间,可以得出其他区块的最佳压后关井恢复时间,从而节省关井时间、提高油产量。

The multi-stage fracturing of horizontal well is of great significance to improve the production capacity of the reservoir and to solve the exploitation of low permeability reservoir.According to diffusion shut-in pressure analysis to 7 Wells at W35 block and 6 Wells at WT43 block and its conclusion,it is found that shut-in time is relevant to pressure drop rate,time of producing oil and production.Using a theoretical formula of the start time of formation radial flow to calculate data of Yuanping 1 block,it is thought that the pressure flow time is 3 times to the formation of radial flow after the start time is the best after shut-in pressure recovery time.The higher the permeability,the shorter the need to close the well;the lower the permeability,the longer it takes to close the well.By calculating the starting time of the formation radial flow,the best pressure of other blocks can be obtained,which will save the time of shut-in and increase the production of oil.