水基完井液静态沉降稳定性回归分析

Regression Analysis of Static Settling Stability of Water-based Completion Fluid

试油完井液在长期高温静置后易降解、固化,引起测试管柱堵塞、封隔器卡埋等井下复杂情况。本文通过研究蓬深2井、磨溪151井和龙兴1井水基完井液在不同密度、不同温度下沉降1~15 d的静态沉降稳定性SSSI值后,通过多元回归分析收敛回归方程,回归方程R^(2)为0.84,残差平方和为0.57。经回归方程计算不同沉降天数的完井液SSSI值,预测完井液未来的沉降情况,SSSI值预测误差均在0.025以下,具有由完井液已知沉降状态预测未知沉降状态的理论价值。

After standing at high temperature for a long time,the test completion fluid is easy to degrade and solidify,leading to test string blockage,packer stuck and other complex downhole conditions,After studying the static settlement stability of the water-based completion fluid in Pengshen 2 well,Moxi 151 well and Longxing 1 well under different densities and temperatures for 1~15 days,the convergence regression equation was analyzed by multiple regression.The regression equation R^(2) was 0.84 and the residual sum of squares was 0.57.SSSI value of completion fluid of different settling days was calculated by regression equation to predict the future settling situation of completion fluid.The prediction error of SSSI value was all less than 0.025,which had the theoretical value of predicting the unknown settling state from the known settling state of completion fluid.