# US 11,905,767 B2 · Mechanical connector utilizing dog-clutch teeth to transfer torque > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,905,767 B2 - Document ID: US11905767B2 - Status: Granted - Kind: B2 - Application number: 17/862,349 - Filed: 2022-07-11 - Published: 2022-11-03 - Granted: 2024-02-20 - Earliest claimed: 2015-04-16 - Applicants: Krzysztof Jan Wajnikonis - Inventors: Krzysztof Jan Wajnikonis - Web page: https://patentgrep.com/patent/US11905767B2 ## CPC - E21B 17/0423: {with plural threaded sections, e.g. with two-step threads} - E21B 17/042: Threaded - E21B 17/046: with ribs, pins, or jaws, and complementary grooves or the like, e.g. bayonet catches - F16L 15/002: {with more than one threaded section} - F16L 15/003: {with sealing rings} - F16L 15/08: with supplementary elements (F16L15/04 takes precedence) - E21B 17/00: Drilling rods or pipes; Flexible drill strings; Kellies; Drill collars; Sucker rods; {Cables;} Casings; Tubings - F16B 33/004: {Sealing; Insulation (by means of washers F16B43/001)} - F16B 33/02: Shape of thread; Special thread-forms ({F16B25/00 takes precedence; used to remove paint or dirt layers F16B35/007, F16B37/002}; used as screw-locking device F16B39/30) - F16L 25/00: Construction or details of pipe joints not provided for in, or of interest apart from, groups F16L13/00 - F16L23/00 (adjustable or allowing movement F16L27/00; with fluid cut-off means F16L29/00; quick-acting F16L37/00; for double-walled or multi-channel pipes F16L39/00; connecting arrangements or other fittings specially adapted to be made of plastics or to be used with pipes made of plastics F16L47/00; specially adapted for pipes of brittle material F16L49/00) - E21B: EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS - F16L: PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL - F16B: DEVICES FOR FASTENING OR SECURING CONSTRUCTIONAL ELEMENTS OR MACHINE PARTS TOGETHER, e.g. NAILS, BOLTS, CIRCLIPS, CLAMPS, CLIPS OR WEDGES; JOINTS OR JOINTING (couplings for transmitting rotation F16D) ## Abstract This invention builds up on technical features and on the industry experience with the use of Merlin™ family connectors. In addition to friction, structural means utilized to transfer high torsional loads include dog-clutch teeth and may also include: interlocked thread systems, shear pins, keys and splines, all used in isolation or in arbitrary combinations. Static and fatigue bending load capacities of the connectors remain high, while the axial load capacities may or may not be high, depending on the design requirements. Connectors according to this invention can be built as new, carefully optimized designs. In some cases upgrading existing Merlin™ family connector designs to increase their torque transfer capacities may be also feasible. ## Claims ### Claim 1 A mechanical connector provided with threads on substantially matching frustoconical surfaces of a box and a pin, said substantially matching frustoconical surfaces of said box and said pin extending essentially between two sets of nipple seals, whereas one said set of said nipple seals is located near an end of said box and another said set of said nipple seals is located near an end of said pin and whereas each said set of said nipple seals incorporates axially engaging, substantially cylindrical surfaces with an outside surface and an inside surface of a male substantially cylindrical segment interacting radially through a mechanism of a hoop stress with substantially matching surfaces of a substantially cylindrical cavity; whereas said threads on said substantially matching essentially frustoconical surfaces of said box and said pin include at least one of: an axisymmetric thread, a left-handed thread, a right-handed thread; whereas said mechanical connector is utilized to connect segments of pipes or tubes transporting fluids; whereas an axis of said box and an axis of said pin coincide with an axis of said mechanical connector; and wherein said mechanical connector includes a one or more set of dog-clutch teeth designed to transfer high torsional loads structurally between said pin and said box, whereas a design order of magnitude of said high torsional loads is of an order of magnitude of design bending loads of said mechanical connector; whereas a correct azimuth orientation of said box relative said pin is assured by an arrangement of said dog-clutch teeth around a circumference of said mechanical connector, including utilizing a non-uniform circumferential pitch distribution of said dog clutch-teeth around said circumference of said mechanical connector; and whereas said one or more set of said dog clutch-teeth is located near said set of said nipple seals. ### Claim 2 (depends on 1) The mechanical connector according to claim 1, whereas said mechanical connector includes an assembly/disassembly fluid remaining liquid during assembly/disassembly operations; wherein after an assembly operation said assembly/disassembly fluid is allowed to solidify in an assembled condition of said mechanical connector and remains essentially solid, thus becoming essentially a solid seal. ### Claim 3 (depends on 2) The mechanical connector according to claim 2, whereas the assembly/disassembly fluid is metallic. ### Claim 4 (depends on 2) The mechanical connector according to claim 2, whereas the assembly/disassembly fluid is non-metallic. ### Claim 5 (depends on 1) The mechanical connector according to claim 1, whereas at least one of the box or the pin utilizes friction welding. ### Claim 6 (depends on 1) The mechanical connector according to claim 1, whereas at least one of the box or the pin is manufactured involving injection molding. ### Claim 7 (depends on 1) The mechanical connector according to claim 1, whereas at least one of the box or the pin is manufactured involving 3D printing. ### Claim 8 (depends on 1) The mechanical connector according to claim 1, whereas at least one of the box or the pin utilizes traditional welding fabrication. ### Claim 9 (depends on 1) The mechanical connector according to claim 1, whereas at least one of the box or the pin is made of at least one of: a high strength steel, or a corrosion resistant alloy, or a titanium alloy, or an aluminum alloy, or a magnesium alloy, or a nickel based alloy, or a non-metallic material including a plastic material, or at least one of said box or said pin utilizes at least one of a lining or a cladding or a weld overlay. ### Claim 10 (depends on 1) The mechanical connector according to claim 1, wherein said mechanical connector includes one or more rib strengthening arranged on at least one of: an inside surface of a pin, or on an outside surface of a box. ### Claim 11 (depends on 1) The mechanical connector according to claim 1, whereas said mechanical connector includes at least one of: a plurality of shear pins, a plurality of keys, a one or more system of interlocking threads comprising at least one of: the left-handed thread interlocking with the right-handed thread, the axisymmetric thread interlocking with the left-handed thread, the axisymmetric thread interlocking with the right-handed thread, the left-handed thread interlocking with a left-handed thread having a different pitch, the right-handed thread interlocking with a right-handed thread having a different pitch. ### Claim 12 (depends on 1) The mechanical connector according to claim 1, whereas the set of the dog-clutch teeth includes one said dog-clutch tooth or more said dog-clutch teeth.