Preparation and Performance Evaluation of Environment-friendly Anti-high Temperature Composite Anti-mud-bag Lubricant

With the development of exploration and development in the direction of deep well, ultra-deep well and ultra-long horizontal section, the formation is complex during drilling. In view of the technical difficulties such as the formation with high mud content and strong hydration easily producing bit mud pack, as well as the high frictional resistance, high torque fluctuation and frequent supporting pressure during drilling in long horizontal section, which seriously affect the construction progress, a kind of copolymer with multiple recognition sites was synthesized by micellar copolymerization, and a new type of micro-nano graphite-polymer composite anti-mud-bag lubricant and drag reducer was developed by intercalating nano-graphite, the results of contact angle and x-ray photoelectron spectroscopy show that the lubricant adsorbs on the surface of the steel sheet preferentially than water, and has a stable coordination with Fe, to improve lubrication. The temperature resistance is more than 160 ℃, the fluorescence grade is less than 2, the lubricating coefficient of base mud with 0.5% lubricant is reduced by 80.0% , and the surface tension of filtrate of drilling fluid is lower than 25 mN/m.The product has significant potential application value in the exploration and development of deep oil and gas.