TOOL OF SCREW FACE MOTOR FOR BOREHOLE DRILLING Russian patent published in 1994 - IPC

FIELD: drilling equipment. SUBSTANCE: sections of tool are interconnected with the aid of joining member which has screw teeth 4. Pitch and direction of teeth of joining member are equal to pitch and direction of teeth 3 of sections. Profile of teeth 4 of joining member id equidistant to profile of teeth 3 of sections. As a result teeth 4 fit snugly to inner screw surfaces 5 of two adjacent sections. For reduction of weight and cost joining member can be manufactured in the form of profiled tubular part with wall of permanent thickness Δ. With feed of flushing fluid inside working pair tool is set in rotation under pressure of unbalanced pressure forces. Moment of force created on sections 1 is transmitted to output shaft of thrust unit of screw motor with the aid of turning joint. EFFECT: increased efficiency and accuracy of orientation of screw teeth of section of tool placed in series when it has wall of permanent thickness. 2 cl, 7 dwg