Research And Application Of Water-based Film Forming Drilling Fluid System

At the present time, with popularization of the diamond wire-line coring drilling technology in geology core drilling filed, the match problem of drilling fluid and diamond wire-line coring drilling technology has exposed now, such as rheology behavior of drilling fluid isn't satisfaction the requirement of diamond wire-line coring drilling technology to drilling fluid, when drilling complex strata especially the water-sensitive strata, the traditional drilling fluid system can't achieve a good effect of wall protection, thus lead to an hole collapsing accident and other issues.Water-based film-forming drilling fluid technology is based on the film-forming theory of water-based drilling fluid, which proposed in recent years. According to this theory, by adding one or several kinds of film former into water-based drilling fluid, so enable it can form a kind of high quality film on the hole wall of strong water sensitivity formation such as shale etc. Thus weaken or prevent filtrate invasion the formation, maintenance the stability of hole wall, and avoid the occurrence of hole accident. Therefore, it's very necessary to introduce the film-forming theory to geology core drilling filed and study it, give it a match system for wire-line coring drilling technology, finally solve these problems.This article from the basic requirements of diamond wire-line coring drilling technology to drilling fluid, use the film-forming theory of water-based drilling fluid, and through a mass of orthogonal tests, research and develop three water-based film- forming drilling fluid systems: the film forming drilling fluid system of gum, the film forming drilling fluid system of silicate and polymer film forming drilling fluid system. These three drilling fluid system have a good film performance and strong restrain ability to the water-sensitive strata. Meanwhile, by using the Regression Analysis Method, finding out the relationship between expansion amount of the standard-core and the time.For research the film forming drilling fluid system of gum, adopting the design and analysis method of orthogonal tests, using the KL gum as the main filming agent, through complex formulation tests of the additive filming agent PAM, PVA and Na2SiO3, selected the better performance complex formulation plan. Form film forming drilling fluid system of gum which has a strong restrain ability to water-sensitive and broken strata.Research of the the film forming drilling fluid system of silicate also adopting the design and analysis method of orthogonal tests, using the Sodium Silicate as the main filming agent, through complex formulation tests of the additive filming agent PAM and inhibitor KCl, selected the better performance complex formulation plan. Form film forming drilling fluid system of gum which has a strong restrain ability to water-sensitive strata.Polymer film forming drilling fluid system including two parts, which are the XY series of polymer film forming drilling fluid system and DP polymer film forming drilling fluid system. XY series of polymer film forming drilling fluid system, using the acrylic polymer as the main filming agent, through complex formulation tests of the additive filming agent WST-100 and S-1. Selected the better performance complex formulation plan DP polymer film forming drilling fluid system using the polyalcohol polymer as the main filming agent, through complex formulation tests of the additive filming agent P and additive C. selected the better performance complex formulation plan. This two kinds of polymer film forming drilling fluid system have a good synthetic wall protected effects to the water-sensitive strata.By practical application with film forming drilling fluid system of gum in ZK003 and ZK6403 of Gu-Xu Coalfield Shi-Bao Ore Section, which belong to the Geological Prospecting Bureau of 113 Team. And also in BZK2 and BZK 19 of landslide Investigation Project, which are in the Erlang Temple of Chongqing Wushan. Solved the problem of wall protection and the rate of core recovery in complex strata.The polymer film forming drilling fluid system applied in ZK0409 and ZK0807 of Copper Investigation Project, which are in Muli Mao-nv-ping of Sichuan. And also applied in ZK11-1 and ZK9-1 of Tangba Coalfield, which is in Junlian of Sichuan. Solved the problem of wall protection in water-sensitive strata and match problem between drilling fluid and diamond wire-line coring drilling technology, good application effect is obtained.