ROLLER CUTTER DRILLING TOOL Russian patent published in 2016 - IPC E21B10/28 

FIELD: mining.

SUBSTANCE: invention relates to rolling drilling tools for drilling with straight stroke of wells with stepped bottom or for expansion of previously drilled wells. Roller cutter drilling tool comprises body, to which leading rock cutting elements are connected, or it has device for connection of leading drilling tool of smaller diameter and/or drill rod, as well as attached legs with trunnions, on each of which there is rolling cutter on bearings arranged through axial orifice, capable to accommodate radial and multidirectional axial load, wherein inner ring of bearing is capable of perception of rolling cutter reverse axial load, rested against housing. Each of bearings is radial-thrust one. Inner bearing race, capable of perception of rolling cutter reverse axial load is installed on trunnion with possibility of axial movement and rested against housing by means of one or more of disk springs. There are two bearings capable to take up from rolling cutter straight axial load, inner ring of one of them, near to top of rolling cutter is installed on trunnion with possibility of axial movement and rested against collar journal through one or more of disk springs. Journal on side opposite to leg, is installed in hole of housing so that by preliminary axial pre-load is formed in radial thrust bearings as result of compression of Belleville springs.

EFFECT: technical result consists in increase of strength of pins of cutters, increasing service life of bearings and reduced labour intensiveness of manufacturing of rock drilling tool.

1 cl, 2 dwg