# US 2017/0254147 A1 · Top drive for a drilling rig > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2017/0254147 A1 - Document ID: US20170254147A1 - Status: Published application - Kind: A1 - Application number: 15/444,339 - Filed: 2017-02-28 - Published: 2017-09-07 - Earliest claimed: 2016-03-02 - Assignees: Mhwirth AS - Applicants: Mhwirth AS - Inventors: STIAN LANTZ - Web page: https://patentgrep.com/patent/US20170254147A1 ## CPC - E21B 3/022: {Top drives} - E21B 19/06: Elevators, i.e. rod- or tube-gripping devices - E21B 19/161: {using a wrench or a spinner adapted to engage a circular section of pipe (E21B19/168 takes precedence)} - E21B: EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS ## Abstract A top drive for a drilling rig includes a top drive housing, a threaded element used in a drilling operation, the threaded element having a grooved surface, and a back-up wrench with a toothed surface which engages with the grooved surface of the threaded element. The back-up wrench is suspended from the top drive housing. The back-up wrench is movable in relation to the top drive housing so as to selectively engage the threaded element. ## Claims ### Claim 1 A top drive for a drilling rig, the top drive comprising: a top drive housing; a threaded element used in a drilling operation, the threaded element comprising a grooved surface; and a back-up wrench comprising a toothed surface which is configured to engage with the grooved surface of the threaded element, wherein, the back-up wrench is suspended from the top drive housing, and the back-up wrench is configured to be movable in relation to the top drive housing so as to selectively engage the threaded element. ### Claim 2 (depends on 1) The top drive as recited in claim 1, wherein the threaded element is a saver sub, a kelly valve, or an inside blow out preventer. ### Claim 3 (depends on 1) The top drive as recited in claim 1, wherein, the top drive further comprises a main drive shaft, and the threaded element is suspended from the main drive shaft. ### Claim 4 (depends on 1) The top drive as recited in claim 1, wherein the grooved surface is arranged in a lower part of the threaded element. ### Claim 5 (depends on 1) The top drive as recited in claim 1, wherein, the top drive further comprises a central longitudinal axis, the back-up wrench further comprises at least one plate, the toothed surface is provided on the at least one plate within the back-up wrench, and the at least one plate is configured to be movable along an axis which is different from the central longitudinal axis of the top drive. ### Claim 6 (depends on 5) The top drive as recited in claim 5, wherein, the back-up wrench comprises two plates, the toothed surface is provided on the two plates within the back-up rench, and the two plates are configured to be individually movable along the axis which is different from the central longitudinal axis of the top drive. ### Claim 7 (depends on 1) The top drive as recited in claim 1, wherein the toothed surface comprises a plurality of teeth which are arranged to project inwardly in relation to the central longitudinal axis of the top drive. ### Claim 8 A top drive for a drilling rig, the top drive having a central longitudinal axis and comprising: a top drive housing; a pivotable coupling; a first suspension element; a second suspension element; a back-up wrench which is suspended from the top drive housing via the first suspension element, the second suspension element, and the pivotable coupling; and a releasable coupling arranged between the first suspension element and the back-up wrench and via which the back-up wrench is fully disconnectable from the first suspension element, wherein, the pivotable coupling is configured to allow a pivoting of the back-up wrench in a plane which is substantially perpendicular to the central longitudinal axis when the back-up wrench is disconnected from the first suspension element. ### Claim 9 (depends on 8) The top drive as recited in claim 8, wherein the pivotable coupling is arranged in the second suspension element. ### Claim 10 (depends on 8) The top drive as recited in claim 8, further comprising: a connection point arranged between the second suspension element and the back-up wrench, wherein, the pivotable coupling is arranged at the connection point. ### Claim 11 (depends on 8) The top drive as recited in claim 8, wherein at least one of the first suspension element and the second suspension element are provided as telescopic cylinders. ### Claim 12 (depends on 8) The top drive as recited in claim 8, wherein the back-up wrench is pivotable around an axis which is parallel to the central longitudinal axis. ### Claim 13 (depends on 12) The top drive as recited in claim 12, wherein the back-up wrench is pivotable around a central axis of the second suspension element. ### Claim 14 (depends on 8) The top drive as recited in claim 8, further comprising: a stack comprising at least one inside blow out preventer; and a main drive shaft, wherein, the top drive comprises, (i) a first operational configuration in which the stack is carried by the main drive shaft, and (ii) a second operational configuration in which the stack is carried by the back-up wrench. ### Claim 15 (depends on 14) The top drive as recited in claim 14, wherein the stack is spaced from the central longitudinal axis of the top drive in the second operational configuration.