WAYS TO INTENSIFY DOWNHOLE PROCESSES OF ROCK DESTRUCTION DURING WELL CONSTRUCTION

Abstract

Purpose. Development of structural foundations for downhole devices (hydraulic hammers) to create dynamic loads on the drilling technological tool and study of the basic physical and chemical processes occurring in their hydraulic circuit and the bottomhole zone of the well. Methodology. The study of the patterns of constructive and technological interaction of the main parts and assemblies of the hydraulic percussion mechanism was carried out when testing its physical model included in the functional diagram of a special drilling stand equipped with appropriate power and hydraulic units, as well as a control and measuring unit. Studies of the physicochemical properties of flushing fluids and their influence on the course of rock mass destruction processes, intensified by the application of generated dynamic loads, were carried out using standardized devices for monitoring the parameters of special process fluids, as well as by bench destruction of experimental rock blocks with the appropriate complex technical measurements. Findings. A basic structural diagram of a hydraulic percussion device has been developed, with its physical embodiment, in which a significantly different execution and functioning of the interacting nodes creates the prerequisites for effective control of the machine in question. The presence of mutual consistency of the circulation processes implemented in the hydraulic hammer model allows its use in various modifications of the regime and technological support of progressive methods of wellbore formation. The proposed hydraulic hammer contains in its design a fairly large number of unified parts and is practically devoid of the presence of wear elements, which ensures its significant motor resource and high maintainability. Simultaneous combination of a hydraulic hammer with the use of activated flushing fluids in the technological scheme of bottomhole assemblies allows to obtain a significant increase in the mechanical fracture rate due to reduced surface tension and acceptable rheological characteristics of the dispersion medium for rock destruction. Originality. The use of alternately different pressure chambers in the design of the hydraulic hammer makes it possible to form a single closed circulation-technical system, with the possibility of effective regulation of its energy performance and operational transition between different drilling modes. Practical value. The proposed layout of the hydraulic percussion machine makes it possible to expand the areas of its possible application in the technical and technological schemes of downhole drilling tools, as well as the implementation of measures to eliminate downhole accidents and complications. Key words: well, hydraulic hammer, drilling, surfactant, rock destruction, flushing fluid, mechanical speed, bottom hole.