Study On The Solution And Analysis To The CBL-VDL Logging Resistance Of Daqing Ajustment Well

The CBL-VDL logging resistance means that in the process of oil well logging process,the performance of the drilling fluid becomes worse,thickened and sedimentary in the casing because of the influence of the internal or the external factor, which can make the logging instrument hit an obstruction in the process of measurement.The basic reason of the CBL-VDL logging resistance is that in the casing part of the drilling fluid is thickened and sedimentary, which makes the instrument be blocked when measuring. The reasons of the thickened property of the part of drilling fluid are mainly to be as following several aspects: the first one is that the displacing drilling fluid is polluted by the residual cement adsorbing on the casing endophragm; the second one is that the density, viscosity and shearing force of the displacing drilling fluid is too small to levitate the solid phase pellet; The third one is that the density, the viscosity and shearing force of displacing drilling fluid is too big to make the instrument go downward for measurement;the last one is that the solids content in the displacement fluid is too high.In the oil well logging process of the adjustment well in Daqing oil field, the situation of the CBL-VDL logging resistance sometimes occur, which seriously affects the well cementation cycle and cementation quality and make very big economic loss.According to the analysis and the experiment about the cementation equipment of adjustment well and the the performance of displacement fluid in Daqing area, this article has determined the reasons which result in the CBL-VDL logging resistance in Daqing adjustment well: the first one is that displacement fluid is polluted by the residual cement adsorbing on the casing endophragm; the second one is that the density, viscosity and shearing force of the displacing drilling fluid is too small to levitate the solid phase pellet. And the HT has been developped to raise shearing force,at the same time the HT also has the anti-cement mortar pollution effect. Meanwhile, low harm well drilling completion fluid which has good performance is used, coordinating the shaker and the desander to control the solids content of the drilling fluid,we succeed in preventing the CBL-VDL logging resistance.for the well tighted pull, optimizing drifting installation can make that the process of drifting dosen't affect the cementation quality through.