Drilling fluid plugging performance evaluation method

Abstract

The invention discloses a drilling fluid plugging performance evaluation method which comprises the following steps: step 1), utilizing a low-temperature low-pressure filter press to measure the API filter loss of drilling fluid to be measured and taking filter cake; step 2) injecting clean water into a drilling fluid cup of the low-temperature low-pressure filter press, covering the drilling fluid cup by the filter cake obtained in step 1); step 3) under the experimental condition the same as the API filter loss of the drilling fluid to be measured, measuring initial permeable time and permeable amount of the filter cake in step 2) and evaluating the strength of the plugging performance of the drilling fluid according to the size of the permeable amount of the filter cake and the initialpermeable time. The evaluation method disclosed by the invention has the advantages that an experiment process is simple, the operability is strong, an experimental period is short, the experimental conditions are closer to the real downhole conditions, and the experimental data and the experimental results have stronger guidance for on-site drilling production; thus, the evaluation method is veryworth of popularization and application.

Description

technical field [0001] The invention belongs to the technical field of oil drilling fluid performance evaluation, and in particular relates to an evaluation method for drilling fluid plugging performance. Background technique [0002] The sealing property of drilling fluid is an important performance index of drilling fluid. Drilling fluid with strong sealing property can prevent or reduce the penetration of drilling fluid filtrate into the rock of the well wall, inhibit rock hydration expansion and collapse, and ensure the stability of the well wall. Ensure the normal progress of drilling construction. [0003] At present, there are not many methods for evaluating the plugging performance of drilling fluid. Usually, the fluid loss test or the sand bed test is used to evaluate the plugging performance. The strength of the wall-building performance of the liquid cannot explain the ability of the created mud cake to prevent the liquid from penetrating into the formation throu...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to overcome above-mentioned deficiencies in prior art, provide a kind of evaluation method of plugging performance of drilling fluid, have overcome in prior art 1: filter loss is evaluated plugging performance relatively one-sided, 2: sand bed experiment The distance between the sands is large, which is quite different from the actual situation of the formation, and it cannot truly simulate the downhole situation. 3: There is a big gap between the experimental results and the field application, etc.