Dependence of the drilling speed on the frictional forces on the cutters of the rock-cutting tool

Abstract

dePendenCe of the drillinG SPeed on the friCtionAl forCeS on the CutterS of the roCk-CuttinG tool Purpose. Forecasting the deepening in one revolution and the mechanical drilling speed, taking into account the decrease in the actual axial load due to the action of the frictional force. Methodology. The analytical model of the vertical and horizontal displacements of the indenter along the surface of the rock has been improved. It is detailed with reference to drilling of boreholes with crowns of cutting type taking into account the reduced actual axial load, acting on the cutter, on rocks with physical and mechanical properties. findings. It is established that during the drilling, the true axial load is less than the nominal load due to the fric tional force arising on the front of the tool. The oneturn and the mechanical drilling speed are predicted taking into account the decrease in the actual axial load due to the action of the vertical friction force. It has been revealed that as the width of the tool is reduced, the axial load losses increase due to friction forces, and the deepening per rotation and the drilling speed decrease more intensively. originality. For the first time, the influence of the frictional force, which appears on the front of the tool of the rock cutting tool on the true axial load, the depression in one turn and the mechanical drilling speed, is shown. New ana lytical dependencies are proposed that allow one to predict the depth per one revolution and the mechanical drilling speed taking into account the design of the rock cutting tool and the geological and technical conditions of dri lling. Practical value. The developed model of the interaction of cutting allows predicting the results of the application of various designs and technologies for the development of a rocksensing tool more reliably, as well as choosing ra tional technologies for their application to achieve maximum technical and economic indicators. keywords: drilling of wells, destruction of rocks, rock cutting tool, carbide crown, perforation in one turn, mechanical drilling speed

Determining key features of the operation of percussion downhole drilling machines

“…In the context of such a technical solution, it is possible to intensify significantly a course of destructive processes and their further development in terms of effective drilling mud removal from the well bottom [7]. Additional introduction of interaction of high-pressure jets with a rock mass of various-origin abrasive materials into a circulation chain can bring significant positive changes at almost all stages of the formation of a rock mass breaking zone [8].…”

Protection of drilling equipment against vibrations during drilling

“…Their correct selection and adjustment can increase the performance and durability of equipment, as well as reduce maintenance and repair costs. Optimal use of these devices is an important step in ensuring efficient and safe drilling [9][10][11][12][13][14].…”

Some features of drilling technology with PDC bits

“…The influence of the tool width on the mechanical drilling rate was also studied in [14]. In particular, when changing the width of the tool from 2 to 0.2 mm (i.e.…”

“…results. The model of interaction of the cutter of a rock destroying tool with a rock, proposed by V. S. Vladislavlev, was improved by us taking into account the influence of the fric tion force arising on the front edge of the cutter of a rockde stroying tool on the true axial load, the groove per revolution and the mechanical drilling speed in [14,15].…”

“…In previous studies, we found that, due to the influence of this friction force, the mechanical speed when drilling with bits with rockbreaking elements with a bluntness of 0.2 mm can be reduced by 20-25 %. In addition, the proposed new analytical dependencies allow predicting the dredging in one turn and the mechanical drilling rate [14].…”