SHOCK ABSORBER-METAL ARRESTER Russian patent published in 1994 - IPC

FIELD: drilling engineering. SUBSTANCE: shock absorber has body 1 and stepped shaft mounted in body for telescopic motion. Smaller diameter step 6 of shaft and body 1 form chamber with flexible member 9 and hydraulic relief chamber 16 communicating with external space. Larger diameter step forms splined chamber with packing for sealing of the latter and chamber with floating piston 21 communicating with splined chamber and with hydraulic relief chamber 16. Located above hydraulic relief chamber 16 and under body 1 are calibrating blades inclined in direction of rotation of body 1 and in opposite direction respectively. Upper part of hydraulic relief chamber 16 is hydraulic communicated with external space either through ports or along entire perimeter. Shaft 5 in space of hydraulic relief chamber 16 is made with stiffening ribs having direction of inclination coincident with that of shaft rotation. In process of drilling vibrations are damped by flexible members 9, sludge is removed from bottom-hole and concurrently stabilization of position of drilling frame in well is gained. EFFECT: enhanced efficiency and durability. 3 cl, 5 dwg