INCREASE OF THE LUBRICATING PROPERTIES OF WATER-CLAY DRILLING MUDS DURING INCLINED AND HORIZONTAL DRILLING

Abstract

The paper presents the results of experimental studies of the antifracturing properties of natural oils: castor, hemp, rapeseed, soybean, mustard, sunflower, and corn. The results of the experiments are presented, which allow to evaluate the effect of the studied natural oils on the parameters of fresh, mineralized and saline-saturated water-clay drilling mud (density, rheological and structural-mechanical properties, pH level, filtration index, thickness and stickiness of the clay crust, lubrication coefficient). The experiment was conducted using the methodology of the American Petroleum Institute (according to API standards). It was established that in the fresh solution, rapeseed oil in concentrations of 1 and 3 % and sunflower oil in a concentration of 1 % showed the most effective lubricating properties, in a mineralized solution - sunflower oil with a concentration of 0.5 % and rapeseed oil with a concentration of 3 %, in a saline-saturated solution - rapeseed oil with a concentration of 1 %. Sunflower oil additives showed satisfactory test results only for fresh and mineralized water-clay drilling mud. Compared to sunflower oil, rapeseed oil showed itself when added to all the tested samples. It can be concluded that the introduction of rapeseed oil provides satisfactory anti-fracture and technological indicators for all types of solutions, therefore rapeseed oil was chosen as the basis of the lubricant additive. Technologically appropriate concentrations of oils are in the range from 1 to 3 %. At these oil concentrations, the negative side effect, in particular on the foaming of the solution, is to a lesser extent, the solutions are characterized by a stable consistency over time, and their lubricating properties are improved. The composition of a lubricating additive based on rapeseed oil was developed for the treatment of various types of water-clay drilling mud.