PDC DRILL BIT WITH DAMPER AND EXPANDABLE SPRING STOPPER FOR ROTATING CUTTERS Russian patent published in 2023 - IPC E21B10/46 E21B10/573 

FIELD: oil and gas industry.

SUBSTANCE: invention relates to a tool for drilling oil and gas wells. The PDC drill bit with a damper and an expanding spring stopper for rotating cutters includes a steel body with protruding blades, flushing units located in the grooves between the blades, a nipple part with a thread for attaching to the drill string, holes on the surfaces of the blades with PDC rotating diamond cutters placed in them. A joint annular cavity is made on the walls of the holes for the cutters and on the walls of the hard-alloy substrates of the cutters. The joint annular cavity is formed by a half-groove in the form of an annular groove on the wall of the hole for the cutter and a half-groove in the form of an annular groove on the wall of the hard-alloy substrate of the cutter. An annular expandable spring stopper with a through groove on the side surface and an annular acute-angled lead-in chamfer is installed in this joint annular cavity with the possibility of squeezing the outer surface of the housing by the hole wall by reducing the width of the through groove during installation and its subsequent restoration when the spring stopper is expanded inside the joint annular cavity. In this case, the difference in the length of the maximum outer circumference of the expandable spring stopper L_exp. in the expanded state (D1) and the length of the maximum outer circumference Lcompressed. expanding spring stopper in a compressed state (D6) corresponds to the inequalities: L_exp. – L_comp. < "a"; π * (D₁ - D₆) < "a", where π is a transdental number known from mathematics, equal to the ratio of the length of any circle to its diameter, π = 3.1415, "a" - the width of the through longitudinal slot on the side surface of the split spring body stopper, between the end face of the PDC cutter and the bottom of the hole under it, a flat damper of a mechanical type is installed, thickness “e” in the expanded state, thickness “i” in the compressed state, the maximum amplitude of the possible movement of the cutter during compression and expansion of the damper is “d”. On the side surface of each carbide substrate, an annular groove is made with a depth limited by diameters D and D₂ and a length L₁, starting at a distance L from the end. On the wall of each hole for the installation of the cutter, a reciprocal annular groove is made with a depth limited by diameters D₁ and D and a length L₃, starting at a distance L₂ from the bottom of the hole. The boundaries of the location and dimensions of the damper, both annular grooves and the expanding spring stopper must be connected by the following relationships: L1 = b + d; where "b" - the height of the body of the split spring stopper, the width of the annular groove of the half-groove on the wall of the carbide substrate of the cutter; L₂ = L+ e; L₃ = L₁ + d; L₄ = L₂+ L₃; e - i = d.

EFFECT: increased durability of PDC diamond bits with rotating cutters, their penetration, mechanical drilling speed, obtaining a large economic effect.

1 cl, 6 dwg