Southwest Petroleum University

Hongbo Li

Yang Bai

Pingya Luo

Chunyan Liu

Hao Kai Zhang

Cheng Li

Yan Cheng

Guojun Li

Dezhi Liu

Gang Xie

Daoxiong Li

Danchao Huang

Chaowei Hu

A method of preparing a modified polyvinyl acetate includes subjecting a mixed liquor Lcontaining a functional monomer to a first reaction with a first vinyl acetate monomer, followed by adding a first initiator to carry out a second reaction to obtain a mixed liquor L; subjecting an acrylate monomer, a second vinyl acetate monomer, a second initiator and the mixed liquor Lto carry out a third reaction to obtain a mixed liquor L; and subjecting a third initiator and the mixed liquor Lto carry out a fourth reaction under the air-tight and ultrasonic conditions. The functional monomer is selected from acrylic acid, oleic acid or butenedioic acid. Uses of modified polyvinyl acetate obtained by the method and oil-based drilling fluid containing the modified polyvinyl acetate are also disclosed.

Modified polyvinyl acetate and preparation method and use thereof and oil-based drilling fluid

The present invention relates to a drilling fluid for enhancing stratum pressure bearing capacity, and a method of preparing and using the drilling fluid. The drilling fluid comprises water, bentonite, low adhesive aggregation anionic cellulose, lignite resin, high temperature resistant and salt resistant filtrate reducer, silanol inhibitor, inorganic micrometer-nanometer rigid particles and emulsified asphalt. The bentonite is 2-9 parts by weight, the low adhesive aggregation anionic cellulose is 0.1-1 parts by weight, the lignite resin is 1-5 parts by weight, the high temperature resistant and salt resistant filtrate reducer is 0.1-2 parts by weight, the silanol inhibitor is 0.1-2 parts by weight, the inorganic micrometer-nanometer rigid particles are 0.5-5 parts by weight, and the emulsified asphalt is 1-10 parts by weight, based on 100 parts by weight of water.

Drilling fluid for enhancing stratum pressure bearing capacity and preparation method and method of using thereof

The invention discloses a method and system for obtaining an evaluation model and an evaluation method and system for the plugging performance of drilling fluid. The method for obtaining the evaluation model comprises: applying a confining pressure to a holding device where a preset fracture model is located, wherein a displacement differential pressure of two ends of the holding device is a preset displacement differential pressure; measuring a flow of standard measuring fluid flowing through the preset fracture model under different confining pressures, wherein the different confining pressures gradually increase according to a first preset rule; and controlling to stop increasing the confining pressure when the flow of the standard measuring fluid flowing through the preset fracture model reaches a preset flow so as to compress the preset fracture model into the evaluation model at a micro-nano level.

Method and system for obtaining micro-nano level fracture model and evaluating plugging performance of drilling fluid

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Chengdu, China

Hongbo Li