METHOD OF BUILDING-UP BIT AXIAL LOAD AND DEVICE FOR ITS EMBODIMENT Russian patent published in 2002 - IPC

FIELD: mining industry, particularly, turbodrilling of oil and gas wells. SUBSTANCE: method consists in building-up of pressure on drilling string by drilling mud by periodic shutting off the inside pipe washing channel of drilling string. Novelty of the method consists in building-up of axial load on drilling bit by increasing fixation of drilling string bottom-hole assembly with respect to well walls at moment of reduction of pressure on drilling string that provides for prevention of reduction of bit axial load caused by action of flexibility of drilling string. The device for building-up of axial load on drilling bit has a hydraulic turbine rigidly connected with eccentric adjacent to disc shutting off the internal washing channel of drilling string and having eccentrically located hole. Novelty of the device for building-up of axial load on drilling bit is packering device on its body with supporting members. Internal space of packering device is communicated with drilling string internal cavity by means of body radial holes located along direction of flow of drilling mud behind disc shutting off the drilling string internal channel. EFFECT: higher efficiency of well drilling due to building-up of axial load on drilling bit sufficient for cutting of rocks. 2 cl, 2 dwg