Serviceable gripping systems for top drives

Abstract

A top drive system comprises a top drive and a tubular gripping system connected to the top drive. A compression assembly is provided which applies a compressive force to a tubular. The main body of the tubular gripping system defines a cavity that is shaped to receive an actuator of the compression assembly. The actuator can be removed from the cavity while the tubular gripping system is connected to the top drive, thereby facilitating maintenance of the actuator and reducing downtime of the top drive.

Description

1 Serviceable Gripping Systems for Top Drives Technical Field

[0001] This invention relates to subsurface drilling. In particular, this invention relates to top drives for subsurface drilling, and tubular gripping systems thereof. 5 Background

[0002] There is a general desire to drill subsurface wells.

[0003] One type of subsurface well is an oil and / or gas well. Oil and / or gas wells may be drilled using drilling rigs. Drilling rigs can comprise top drives that provide torque to the drill string to facilitate the creation of a borehole. 10

[0004] Top drives may require maintenance. One portion of top drives requiring maintenance includes the tubular gripping system. The tubular gripping system is connected to the top drive and grips tubulars (e.g. drill pipe).

[0005] The tubular gripping system facilitates making and / or breaking connections (e.g. between individual pipe tubulars) on the drill string near the top drive. 15

[0006] Over the course of operation, tubular gripping systems may need maintenance and / or replacement. Maintenance and / or replacement of parts can be particularly important for hydraulic tubular gripping systems, as components of hydraulic tubular gripping systems (e.g. seals, pistons, and lock rings) can be prone to wearing down over time. Maintenance and / or replacement of parts can also become necessary because of acute damage events. 20

[0007] Extended downtime of a tubular gripping system for maintenance or repair may cause the gripping system and / or the top drive to be taken offline, which may be expensive and result in lost revenue.

[0008] There remains a need for tubular gripping systems that are simple and cost-effective to maintain. 25

[0009] The foregoing examples of the related art and limitations related thereto are intended to be illustrative and not exclusive. Other limitations of the related art will become apparent to those of skill in the art upon a reading of the specification and a study of the drawings. CA 3301044 Date reçue / Received date 2026-02-05 2 Summary

[0010] The following embodiments and aspects thereof are described and illustrated in conjunction with systems, tools and methods which are meant to be exemplary and illustrative, not limiting in scope. In various embodiments, one or more of the abovedescribed problems have been reduced or eliminated, while other 5 embodiments are directed to other improvements.

[0011] One aspect of the invention provides an apparatus for a top drive system, the apparatus comprising: a tubular gripping system comprising a main body, and a compression assembly comprising an actuator; wherein the main body is shaped to define 10 a cavity for receiving the actuator and the actuator is removably mountable to the main body inside the cavity for generation of compressive force applicable to a tubular.

[0012] In some embodiments, the apparatus further comprises a top drive wherein the tubular gripping system is connected to the top drive and wherein the actuator is detachable from the main body and removable from the cavity while tubular gripping system is 15 connected to the top drive.

[0013] In some embodiments, the top drive comprises a post which projects through a postreceiving opening defined in the main body and wherein a connection between the tubular gripping system and the top drive comprises a connection of the main body to the post; the cavity is shaped to provide a cavity opening through which the actuator is insertable into, 20 and removable from, the cavity; and the cavity opening is spaced apart from the postreceiving opening on the main body to facilitate insertion of the actuator into the cavity, and removal of the actuator from the cavity, through the cavity opening while the tubular gripping system is connected to the top drive.

[0014] The cavity opening may be oriented such that a direction of insertion of the actuator 25 into the cavity and a direction of removal of the actuator from the cavity are generally aligned with (e.g. parallel to) a direction through which the post projects through the postreceiving opening.

[0015] The actuator may be a hydraulic actuator comprising: a cylinder-defining member shaped to define a bore-defining surface that defines a cylinder bore; a piston shaped for 30 reciprocal movement in an axial direction within the cylinder bore; and one or more seals CA 3301044 Date reçue / Received date 2026-02-05 3 located for slidable engagement between an outer surface of the piston and the boredefining surface.

[0016] In some embodiments, an exterior surface of the cylinder-defining member comprises one or more shoulders shaped to provide corresponding shoulder surfaces; the actuator is removably mountable to the main body inside the cavity by 5 one or more plates which are couplable to the main body such that each of the one or more plates abuts against the exterior surface and against a corresponding one of the shoulder surfaces to retain the actuator within the cavity.

[0017] Each of the one or more plates may be located in the cavity when coupled to the 10 main body to abut against the exterior surface and against the corresponding one of the shoulder surfaces. Each of the one or more plates may abut against a portion of the exterior surface that provides a generally vertical face. Each of the one or more plates may abut against a generally horizontally oriented shoulder face.

[0018] In some embodiments, the cavity is enclosable by a panel. 15

[0019] Another aspect of the invention provides a top drive drilling system, the system comprising: a tubular gripping system comprising a main body, and a compression assembly comprising an actuator; wherein the actuator is removably mountable to the main body for generation of compressive force applicable to a tubular.

[0020] In some embodiments, the system further comprises a top drive, wherein the tubular 20 gripping system is connected to the top drive and wherein the actuator is removable from the main body while tubular gripping system is connected to the top drive.

[0021] In some embodiments, the top drive comprises a post which projects through a postreceiving opening defined in the main body and wherein a connection between the tubular gripping system and the top drive comprises a connection of the main body to the post; and 25 the actuator is removably mountable to the main body at a location that is spaced apart from the post to facilitate removably mounting the actuator to the main body without interference from the post.

[0022] The main body may be shaped to define a cavity for receiving the actuator and the actuator may be removably mountable to the main body inside the cavity. CA 3301044 Date reçue / Received date 2026-02-05 4

[0023] In some embodiments, the cavity is shaped to provide a cavity opening through which the actuator is insertable into, and removable from, the cavity; and the cavity opening is spaced apart from the post-receiving opening on the main body to facilitate insertion of the actuator into the cavity, and removal of the actuator from the cavity, through the cavity opening while the tubular gripping system is connected 5 to the top drive.

[0024] In some embodiments, the cavity opening is oriented such that a direction of insertion of the actuator into the cavity and a direction of removal of the actuator from the cavity are generally aligned with (e.g. parallel to) a direction through which the post projects through the post-receiving opening. 10

[0025] The actuator may comprise a hydraulic actuator comprising: a cylinder-defining member shaped to define a bore-defining surface that defines a cylinder bore; a piston shaped for reciprocal movement in an axial direction within the cylinder bore; and one or more seals located for slidable engagement between an outer surface of the piston and the bore-defining surface. 15

[0026] In some embodiments, an exterior surface of the cylinder-defining member comprises one or more shoulders shaped to provide corresponding shoulder surfaces; the actuator is removably mountable to the main body inside the cavity by one or more plates which are couplable to the main body such that each of the one or more plates abuts against the exterior surface and against a corresponding one of the shoulder surfaces to 20 thereby retain the actuator in the cavity.

[0027] Another aspect of the invention provides a method of servicing a tubular gripping system for a top-drive drilling system, the method comprising: detaching an actuator from a main body of the tubular gripping system while the main body is connected to a top drive of the top-drive drilling system; and removably mounting a second actuator to the main body 25 while the main body is connected to the top drive.

[0028] In some embodiments, detaching the actuator from the main body comprises removing the actuator from inside of a cavity defined in the main body; and removably mounting the second actuator to the main body comprises inserting the second actuator into the cavity and removably mounting the second actuator to the main body while the 30 second actuator is located in the cavity. CA 3301044 Date reçue / Received date 2026-02-05 5

[0029] In some embodiments, the top drive comprises a post which projects through a postreceiving opening defined in the main body and wherein a connection between the tubular gripping system and the top drive comprises a connection of the main body to the post; detaching the actuator from the main body comprises detaching the actuator from a location that is spaced apart from the post to facilitate detaching the actuator 5 from the main body without interference from the post; and removably mounting the second actuator to the main body comprises removably mounting the second actuator to the main body at the location so spaced apart from the post to facilitate removably mounting the actuator to the main body without interference from the post. 10

[0030] In some embodiments, the top drive comprises a post which projects through a postreceiving opening defined in the main body and wherein a connection between the tubular gripping system and the top drive comprises a connection of the main body to the post; removing the actuator from the inside of the cavity comprises removing the actuator in a removal direction that is generally aligned with (e.g. parallel to) a direction through which 15 the post projects through the post-receiving opening; and inserting the second actuator into the cavity comprises inserting the actuator in an insertion direction that is generally aligned with (e.g. parallel to) the direction through which the post projects through the postreceiving opening.

[0031] In some embodiments, the second actuator comprises a hydraulic actuator 20 comprising: a cylinder-defining member shaped to define a bore-defining surface that defines a cylinder bore; a piston shaped for reciprocal movement in an axial direction within the cylinder bore; and one or more seals located for slidable engagement between an outer surface of the piston and the bore-defining surface; and an exterior surface of the cylinderdefining member comprises one or more shoulders shaped to provide corresponding 25 shoulder surfaces; and removably mounting the second actuator to the main body comprises: coupling one or more plates to the main body such that each of the one or more plates abuts against the exterior surface and against a corresponding one of the shoulder surfaces to thereby mount the second actuator to the main body.

[0032] In addition to the exemplary aspects and embodiments described above, further 30 aspects and embodiments will become apparent by reference to the drawings and by study of the following detailed descriptions. CA 3301044 Date reçue / Received date 2026-02-05 6 Brief Description of the Drawings

[0033] Exemplary embodiments are illustrated in referenced figures of the drawings. It is intended that the embodiments and figures disclosed herein are to be considered illustrative rather than restrictive.

[0034] Figure 1A is a side view of a prior 5 art top drive.

[0035] Figure 1B is a side view of a prior art tubular gripping system mounted (e.g. connected or otherwise affixed) to a top drive.

[0036] Figure 1C is a perspective view of a prior art tubular gripping system mounted to a top drive. 10

[0037] Figure 2A is a top view of a prior art tubular gripping system detached from its top drive and shown without its gate.

[0038] Figure 2B is a side view of the Figure 2A prior art tubular gripping system.

[0039] Figure 2C is a cutaway view of the Figure 2A prior art tubular gripping system shown without the piston and piston holder of its compression assembly. 15

[0040] Figure 2D is a perspective view of the Figure 2A prior art tubular gripping system including its gate.

[0041] Figure 2E is a cutaway view of the Figure 2A prior art tubular gripping system with its compression assembly shown therewithin.

[0042] Figure 3A is a top view of a tubular gripping system detached from its top drive, 20 shown without its gate and shown without a compression assembly according to an example embodiment.

[0043] Figure 3B is a side view of the Figure 3A tubular gripping system.

[0044] Figure 3C is a cutaway view of the Figure 3A tubular gripping system.

[0045] Figure 3D is a top view of the Figure 3A tubular gripping system with a compression 25 assembly removably received therein.

[0046] Figure 3E is a cutaway view of the Figure 3A tubular gripping system with a compression assembly removably received therein. CA 3301044 Date reçue / Received date 2026-02-05 7

[0047] Figure 3F is a side view of the Figure 3A tubular gripping system with a compression assembly removably received therein.

[0048] Figure 3G is a perspective view of the Figure 3A tubular gripping system including its gate with a compression assembly removably received therein.

[0049] Figure 3H is a perspective view of the Figure 3A tubular gripping 5 system with a compression assembly removably received therein.

[0050] Figure 3I is an exploded view of the Figure 3A tubular gripping system and its compression assembly with its compression assembly shown as removed from the gripping system. 10 Description

[0051] Throughout the following description specific details are set forth in order to provide a more thorough understanding to persons skilled in the art. However, well known elements may not have been shown or described in detail to avoid unnecessarily obscuring the disclosure. Accordingly, the description and drawings are to be regarded in an illustrative, 15 rather than a restrictive, sense.

[0052] Figure 1A shows a prior art top drive drilling system 10. Top drive drilling system 10 comprises top drive 11. Top drive 11 comprises motor 12A and motor 12B. Motor 12A and motor 12B are coupled to shaft 14 by a gearbox (not shown). Shaft 14 is coupled to a drill string (not shown) by blow out preventer valve 16 (which can also be referred to as inside 20 blow out preventer valve 16 and / or IBOP valve 16), and saver sub 18. Shaft 14 may also be referred to as a quill 14.

[0053] Top drive 11 rotates a tubular (not shown) and / or a drill string (not shown), which may comprise a plurality of tubulars. Top drive 11 may be situated in a derrick at a wellsite and may be raised and lowered or otherwise moved during a drilling operation as tubulars 25 are added to and / or removed from a drill string.

[0054] Figure 1B and Figure 1C show side and perspective views respectively of a prior art tubular gripping system 100. During a drilling operation, connections are repeatedly made and broken between tubulars (not shown) and saver sub 18. Tubulars may repeatedly threadably attach and detach from saver sub 18. It is desirable to avoid replacement of 30 IBOP valve 16 and / or shaft 14, as replacing and / or servicing IBOP valve 16 and / or shaft 14 CA 3301044 Date reçue / Received date 2026-02-05 8 may require top drive system 10 to be taken offline for a significant amount of time. Consequently, at least one purpose of saver sub 18 is to act as a sacrificial component that can be easily replaced. When saver sub 18 wears and / or degrades (e.g. after repeated making and breaking of connections with tubulars), saver sub 18 can be replaced by unthreading saver sub 18 from IBOP valve 16 and threading a new saver 5 sub 18 onto IBOP valve 16.

[0055] Prior art tubular gripping system 100 is mounted (e.g. connected or otherwise affixed) to top drive 11 by post 20. Figures 2A-2E (collectively, Figure 2) show various views of prior art tubular gripping system 100. 10

[0056] To facilitate the making and breaking of connections between tubulars and saver sub 18, prior art tubular gripping system 100 applies a compressive force to the tubular. The compressive force applied by prior art tubular gripping system 100 generates a frictional force between prior art tubular gripping system 100 and the tubular that resists relative rotation between the tubular and gripping system 100. In this way, tubulars can be fastened 15 and / or unfastened (e.g. by threading or unthreading a threaded connection) from saver sub 18 by applying a torque to saver sub 18 with one or both of motor 12A and motor 12B, while tubular gripping system 100 resists rotation of the tubular.

[0057] Tubular gripping system 100 may require periodic maintenance. Drilling operations are also expensive. Consequently, it is desirable to minimize the complexity of maintaining 20 and / or servicing prior art tubular gripping system 100 and the corresponding time involved with same.

[0058] Figures 2A, 2B and 2C are respectively top, side and cutaway views of prior art tubular gripping system 100 without its gate and detached from top drive 11 for ease of viewing the features of prior art gripping system 100. Prior art tubular gripping system 100 25 comprises main body 101. Main body 101 is shaped to define post-receiving opening 102, which can receive a post from a top drive (e.g. post 20 on top drive 11) and to thereby mount gripping system 100 to post 20. Main body 101 further comprises a curved (e.g. arcuate or quasi-arcuate) surface 104 shaped to abut with the outer surface (e.g. outer cylindrical surface) of a tubular. 30

[0059] As shown best in Figure 2D, prior art tubular gripping system 100 further comprises a gate 112 which is affixed (e.g. removably) to main body 101 via suitable connection posts CA 3301044 Date reçue / Received date 2026-02-05 9 (not shown) that extend through mounting bores 106A, 106B, 106C, 106D (collectively, mounting bores 106) defined by main body 101 and corresponding mounting bores (not expressly enumerated) in the body of gate 112. Together, main body 101 and gate 112 define a space 108 for receiving tubulars. Stabilizers 114A, 114B, 114C, 114D (collectively, stabilizers 114) may be positioned around all or a portion of a perimeter 5 of space 108. Stabilizers 114 may be affixed to either curved surface 104 (as is the case with stabilizers 114A, 114B in the illustrated embodiment) or gate 112 (as is the case with stabilizers 114C, 114D in the illustrated embodiment). Stabilizers 114 may help to facilitate the alignment of tubulars in space 108 and with saver sub 18. 10

[0060] Tubular gripping system 100 comprises compression assembly 120 (shown best in the cut-away view of Figure 2E). Compression assembly 120 applies a compressive force to tubulars in space 108. Compression assembly 120 applies a compressive force in the direction indicated by arrow 110.

[0061] As shown in Figure 2E, compression assembly 120 of the Figure 2 embodiment 15 comprises a hydraulic actuator 122, which provides a compressive force (in direction 110) to compression assembly 120 and tubular gripping system 100. In the illustrated example of the Figure 2 prior art tubular gripping system 100, actuator 122 comprises a piston 123 which moves linearly (e.g. in direction 110 and antiparallel to direction 110) within a corresponding cylindrical bore (or cylinder) 124 to provide the compressive force. In the 20 Figure 2 prior art tubular gripping system 100, cylinder 124 is defined by bore-defining surface 124A which is a surface of main body 101 – see Figure 2C and Figure 2E. That is, a part of hydraulic actuator 122 is integral with main body 101.

[0062] Compression assembly 120 and in particular, but without limitation, hydraulic actuator 122, may require maintenance from time to time. For example, repeated actuation 25 of compression assembly 120 may require compression assembly 120 to undergo maintenance (e.g. due to wear).

[0063] Hydraulic actuator 122 may comprise one or more seals 125 located for slidable engagement between outer surface 123A of piston 123 and bore-defining surface 124A of cylinder 124. Seal(s) 125 may wear down over time, degrading the ability for compression 30 assembly 120 (and, in particular, hydraulic actuator 122) to apply a compressive force and, CA 3301044 Date reçue / Received date 2026-02-05 10 in turn, reducing the efficacy of gripping system 100 to grip tubulars. Consequently, there is a desire to replace seals 125 periodically.

[0064] By way of further non-limiting example, bore-defining surface 124A may have a machined, polished and / or chromed finish. Periodic re-finishing of bore-defining surface 124A may be desirable to maintain performance of compression assembly 5 120. It may also be desirable to re-finish outer surface 123A of piston 123 from time to time.

[0065] By way of further non-limiting example, piston holder 129 may have a lock ring 129A that circumscribes piston holder 129. Lock ring 129A may be received by both lock ring groove 129B (etched into the circumference of piston holder 129), and lock ring groove 10 129C (etched into bore defining surface 124A). Lock ring 129A retains piston holder 129 in place. Lock ring 129A may require replacement and / or servicing over the course of a drilling operation. This may be, for example, due to force applied to lock ring 129A as hydraulic actuator 122 actuates, and / or from tubular gripping system 100 vibrating or incurring shock loads during operation. 15

[0066] Compression assembly 120 may additionally or alternatively require maintenance due to acute damage events, which may be caused, for example, by moving tubulars, other wellhead components and / or the like.

[0067] Replacing and / or servicing compression assembly 120 or parts thereof in prior art tubular gripping system 100 may be arduous and / or expensive. For example, to replace 20 seals 125 within compression assembly 120, compression assembly 120 or parts thereof (e.g. piston 123, piston holder 129 and / or seals 125) must first be removed from gripping system 100. However, in prior art gripping system 100, parts of compression assembly 120 (e.g. piston 123, cylinder 124, seals 125 and / or lock ring 129A) are not accessible or removable or otherwise serviceable when gripping system 100 is mounted to a 25 corresponding top drive. More specifically, piston 123 is not accessible when gripping system 100 is mounted to a corresponding top drive because: piston 123 is located in a bore of cylinder 124 which is integrally formed with main body 101; the shape of the outer surface 123A of piston 123 and / or bore-defining surface 124A of cylinder 124 (e.g. having respectively radially outwardly extending and radially inwardly extending shoulders 123B, 30 124B) prevent removal of piston 123 via proximate end 126A of cylinder 124; and access to piston 123 from the distal end 126B of cylinder 124 via piston holder 129 is blocked by post CA 3301044 Date reçue / Received date 2026-02-05 11 20 that normally extends through post-receiving opening 102 when gripping system 100 is mounted to the top drive (e.g. top drive 11). Seals 125 are not accessible when gripping system 100 is mounted to a corresponding top drive because seals 125 are maintained in their positions between piston 123 and cylinder 124 by seating grooves 127 and so are not accessible unless piston 123 is first removed from cylinder 124. Lock ring 5 129A is also not accessible when gripping system 100 is mounted to a corresponding top drive because access to piston holder 129 is blocked by post 20 extending through post-receiving opening 102. Cylinder 124 is not accessible when gripping system 100 is mounted to a corresponding top drive because cylinder 124 is integrally formed with main body 101 and 10 because piston 123 must be removed from cylinder 124 before cylinder 124 can be accessed for servicing.

[0068] Consequently, to replace or service the parts of compression assembly 120 (e.g. piston 123, cylinder 124 and / or seals 125), prior art tubular gripping system 100 must first be removed from the top drive to which it is attached (for example, top drive 11). Thereafter, 15 prior art tubular gripping system 100 may need to be disassembled (for example, by removing piston holder 129 from main body 101) to thereby remove piston 123 from the distal end 126B of cylinder 124 and to provide access to piston 123, cylinder 124 and / or seals 125. Such maintenance may be costly and may result in significant downtime for the drilling operation. As previously mentioned, it is desirable to minimize downtime in a drilling 20 operation and, therefore, it is undesirable to have to remove gripping system 100 from its corresponding top drive to service the components of the gripping system.

[0069] Figures 3A-3I (collectively, Figure 3) show various views of a tubular gripping system 200 according to a particular embodiment of the invention comprising a removably mountable compression assembly 220 that is removable from the rest of tubular gripping 25 system 200 while gripping system 200 remains mounted to its top drive (e.g. top drive 11). Except where the context indicates otherwise, those elements of tubular gripping system 200 identified with reference numerals that are the same reference numerals as elements of prior art tubular gripping system 100 have the same or similar features and / or functions as described with respect to prior art tubular gripping system 100. 30

[0070] Figure 3A, Figure 3B, and Figure 3C are respectively top, side, and cutaway views of tubular gripping system 200 (without its gate and detached from its corresponding top CA 3301044 Date reçue / Received date 2026-02-05 12 drive). In the illustrated views of Figures 3A, 3B and 3C, compression assembly 220 is removed from the rest of tubular gripping system 200.

[0071] Analogous to prior art gripping system 100 described above, main body 201 of tubular gripping system 200 comprises a curved surface 204 (e.g. arcuate or quasi-arcuate) shaped to accommodate the outer surface (e.g. outer cylindrical surface) 5 of tubulars to be gripped. Main body 201 of tubular gripping system 200 differs from main body 101 of tubular gripping system 100 for at least the reason that main body 201 of tubular gripping system 200 is shaped to define cavity 250 as shown in Figures 3A, 3B and 3C. Cavity 250 may receive a removable compression assembly 220 (not shown in Figures 3A, 3B or 3C). 10 Specifically, compression assembly 220 (shown in Figures 3D-3I and described in more detail below) may be removably received (e.g. mounted) in cavity 250 and, when so mounted, may apply a compression force to tubulars.

[0072] Figures 3D-3H depict various views of tubular gripping system 200 with its compression assembly 220 mounted in cavity 250 and Figure 3I is an exploded view of 15 tubular gripping system 200 and its compression assembly 220 with its compression assembly 220 shown as removed from tubular gripping system 200.

[0073] Compression assembly 220 is insertable into cavity 250. Compression assembly 220 is also removably attachable to main body 201 of tubular gripping system 200. Compression assembly 220 may be mounted to main body 201 of tubular gripping system 20 200 by a plurality of fasteners. In the particular case of the Figure 3 example embodiment, the fasteners comprise bolts 252A, 252B, 252C, 252D (collectively, bolts 252) which extend through apertures 253A, 253B, 253C, 253D (collectively, apertures 253). Bolts 252 may threadably fasten directly to compression assembly 220 (e.g. to cylinder-defining member 275 and / or to some other part of compression assembly 220). In the illustrated Figure 3 25 embodiment (as shown best in Figure 3I), bolts 252A, 252B fasten to plate 276A, and bolts 252C, 252D fasten to plate 276B. When so fastened, plates 276A, 276B may engage generally horizontally oriented shoulders 275B on the exterior surface 275A of cylinderdefining member 275 of compression assembly 220 (see Figure 3I). When so fastened, plates 276A, 276B may also abut against generally vertically oriented faces 275C on 30 exterior surface 275A of cylinder defining member 275. Although plates 276A, 276B are optional, plates 276A, 276B help to distribute the stresses experienced by the mounting of compression assembly 220 to main body 201 during operation. CA 3301044 Date reçue / Received date 2026-02-05 13

[0074] Cavity 250 of the Figure 3 embodiments is at least partially enclosable (after compression assembly 220 is removably received therein) by panel 254. As shown in Figure 3I, panel 254 may be removably fastened to cylinder-defining member 275 (e.g. by bolts 254A which may project into corresponding threaded apertures 255 on top face 275D of exterior surface 275A of cylinder-defining member 275). In some 5 embodiments, panel 254 may be additionally or alternatively attached to main body 201 using similar connection techniques. When cavity 250 is enclosed by panel 254, panel 254 may ameliorate the ingress of debris into cavity 250. Panel 254 may be removed (e.g. detached from the rest of gripping system 200) for access to cavity 250 and compression assembly 220. 10

[0075] As shown best in Figure 3E, compression assembly 220 comprises an actuator 222, which in the Figure 3 embodiment is a hydraulic actuator 222. Hydraulic actuator 222 provides a compressive force to compression assembly 220 and to tubular gripping system 200. Hydraulic actuator 222 of the Figure 3 embodiment comprises a piston 223 which reciprocates axially (e.g. in direction 210 and antiparallel to direction 210) within a 15 corresponding cylindrical bore (or cylinder) 224 to provide the compressive force. Unlike the prior art compression assembly 120 described above, cylinder 224 is not defined by main body 201 of tubular gripping system 200. Instead, in the Figure 3 tubular gripping system 200, cylinder 224 in compression assembly 220 is defined by the bore-defining surface 224A of a cylinder-defining member 275, where cylinder-defining member 275 is a discrete 20 component that is separate from (and removably attachable to) main body 201. Hydraulic actuator 222 may have other features similar to those of hydraulic actuator 122 described above. In particular, outer piston surface 223A, seals 225 and seating grooves 227 may be similar to outer piston surface 123A, seals 125 and seating grooves 127 of hydraulic actuator 122 described above. 25

[0076] Analogous to compression assembly 120 of prior art tubular gripping system 100, compression assembly 220 of tubular gripping system 200 may apply a compressive force to tubulars in the direction indicated by arrow 210 in Figure 3E.

[0077] Lock ring 228 may retain piston 223 within cylinder-defining member 275 by holding radially inwardly extending shoulder 229 in place. Radially inwardly extending shoulder 229 30 abuts with radially outwardly extending shoulder 223B of piston 223 when piston 223 is in an extended state. If necessary or desirable, piston 223 can be removed from cylinder defining member 275 by (1) removing compression assembly 220 from cavity 250, (2) CA 3301044 Date reçue / Received date 2026-02-05 14 removing lock ring 228 from cylinder defining member 275, (3) removing radially inwardly extending shoulder 229 from cylinder defining member 275, and (4) prying piston 223 from cylinder defining member 275. The provision of lock ring 228 simplifies access to components within compression assembly that may require periodic maintenance (e.g. seals 225). Lock ring 228 may require periodic maintenance as it may 5 wear down over the course of a drilling operation for at least the same reasons as described above with respect to lock ring 129A.

[0078] In some embodiments, hydraulic module 256, which may be operatively coupled to compression assembly 220 (e.g. to hydraulic actuator 222), provides a hydraulic connection 10 to compression assembly 220. Hydraulic module 256 of the illustrated embodiment comprises hydraulic connectors 256A, 256B which may be detachably connected to complementary connectors of an external hydraulic source of hydraulic fluid. In the illustrated embodiment, hydraulic module 256 extends out of (e.g. upwardly from) cavity 250 and outside of panel 254 such that hydraulic connectors 256A, 256B are accessible when 15 compression assembly 220 is mounted in, and panel 254 extends over, cavity 250.

[0079] As shown in Figure 3G, gripping system 200 comprises a gate 112 which attaches to main body 201 and, together with main body 201, defines space 108 for receiving a tubular. Gate 112 of tubular gripping system 200 and the way that it attaches to main body 201 and works with main body 201 and compression assembly 220 may be substantially similar to 20 that of gate 112 of tubular gripping system 100 and the way that gate 112 attaches to main body 101 and works with main body 101 and compression assembly 120.

[0080] As best shown in Figure 3H, grip 280 may be provided on proximate surface 223C of piston 223 to provide frictional force at the contact region / surface between gripping system 200 and tubulars. Grip 280 may be affixed to proximate surface 223C of piston 223 by 25 fasteners (not expressly shown) received in apertures 280A. Grip 280 may abut with a tubular when compression assembly 220 applies a compressive force and moves piston 223 in direction 110. Grip 280 may have a curved (e.g. concave, arcuate or quasi-arcuate) gripping surface 281 shaped to abut with, and be complementary to, the outer surface (e.g. outer cylindrical surface) of a tubular. Gripping surface 281 or portions thereof may be 30 textured (e.g. with a plurality of protrusions, indents and / or the like) which may provide frictional force between gripping surface 281 and tubulars (as compared to non-textured gripping surfaces). Grip 280 and / or gripping surface 281 may be elastically deformable or at CA 3301044 Date reçue / Received date 2026-02-05 15 least deformable relative to tubulars and relative to piston 223, although this is not necessary.

[0081] Grip 280 and / or gripping surface 281 may wear down over repeated use or may be acutely damaged during operation. Consequently, in some embodiments, grip 280 may be replaceable by removing grip 280 from tubular gripping system 200 by 5 removing fasteners via apertures 280A and mounting a replacement grip 280’ (not shown).

[0082] Tubular gripping system 200 may also comprise stabilizers 214A, 214B, 214C, 214D (collectively stabilizers 214). Stabilizers 214 may facilitate the alignment of tubulars with saver sub 18. Stabilizers 214 may be removably attachable to main body 201 and / or gate 10 112 of tubular gripping system 200 by one or more fasteners 277. As visible in Figure 3G, stabilizers 214A and 214B are removably attachable to curved surface 204 of main body 201 of tubular gripping system 200, and stabilizers 214C and 214D are removably attachable to gate 112 of tubular gripping system 200, where gate 112 may comprise a curved (e.g. concave) surface (obscured by stabilizer 214C in Figure 3G) similar to curved 15 surface 204 of main body 201.

[0083] Figure 3I is an exploded view of tubular gripping system 200. As is evident from Figure 3I, tubular gripping system 200 provides for simple replacement and / or servicing of compression assembly 220. In particular, compression assembly 220 and / or its parts (e.g. piston 223, cylinder 224, seal(s) 225 and / or the like) are removably attachable to main body 20 201 (or the rest of gripping system 200) and may be removed from main body 201 / gripping system 200 for service and / or maintenance while main body 201 (or the rest of tubular gripping system 200) remains connected to top drive 11.

[0084] By way of example, if one or more of seals 225 of hydraulic actuator 222 had worn down in compression assembly 220, seals 225 may need replacement and / or maintenance. 25 In this circumstance, compression assembly 220 could be removed from main body 201 (or the rest of tubular gripping system 200) by removing panel 254 and removing bolts 252 affixed to compression assembly 220 and / or to plates 276A / 276B. If applicable, hydraulic connections could be detached from hydraulic connectors 256A, 256B. Stabilizers 214A, 214B could also be detached from tubular gripping system 200 prior to removing 30 compression assembly 220. Compression assembly 220 could then be withdrawn from cavity 250 (in a removal direction indicated by arrow 290). The removal of compression CA 3301044 Date reçue / Received date 2026-02-05 16 assembly 220 may take place while main body 201 remains attached to its top drive (e.g. top drive 11).

[0085] After removing compression assembly 220, a new compression assembly 220 or a serviced version of compression assembly 220 could be mounted within cavity 250 (in an insertion direction indicated by arrow 291). Bolts 252 could thereafter 5 be affixed either directly to compression assembly 220 or to plates 276A, 276B. Panel 254 could also be reinstalled. External hydraulic connections could then be reattached to hydraulic connector 256A and 256B on hydraulic module 256. If previously removed, stabilizers 214A, 214B could be reattached to tubular gripping system 200. 10

[0086] The removed compression assembly 220 could be sent away for maintenance and / or the like.

[0087] The provision of cavity 250 and the ability to removably mount compression assembly 220 to main body 201 of gripping system 200 facilitates replacement of compression assembly 220 while main body 201 (or the rest of gripping system 200) 15 remains mounted to its top drive, thereby reducing downtime of tubular gripping system 200 and its top drive 11.

[0088] Unless the context clearly requires otherwise, throughout the description and the claims: • “comprise”, “comprising”, and the like are to be construed in an inclusive sense, as 20 opposed to an exclusive or exhaustive sense; that is to say, in the sense of “including, but not limited to”; • “connected”, “coupled”, or any variant thereof, means any connection or coupling, either direct or indirect, between two or more elements; the coupling or connection between the elements can be physical, logical, or a combination thereof; 25 • “herein”, “above”, “below”, and words of similar import, when used to describe this specification, shall refer to this specification as a whole, and not to any particular portions of this specification; • “or”, in reference to a list of two or more items, covers all of the following interpretations of the word: any of the items in the list, all of the items in the list, and 30 any combination of the items in the list; • the singular forms “a”, “an”, and “the” also include the meaning of any appropriate plural forms. CA 3301044 Date reçue / Received date 2026-02-05 17

[0089] Words that indicate directions such as “vertical”, “transverse”, “horizontal”, “upward”, “downward”, “forward”, “backward”, “inward”, “outward”, “left”, “right”, “front”, “back”, “top”, “bottom”, “below”, “above”, “under”, and the like, used in this description and any accompanying claims (where present), depend on the specific orientation of the apparatus described and illustrated. The subject matter described herein 5 may assume various alternative orientations. Accordingly, these directional terms are not strictly defined and should not be interpreted narrowly.

[0090] While processes or blocks are presented in a given order, alternative examples may perform routines having steps, or employ systems having blocks, in a different order, and 10 some processes or blocks may be deleted, moved, added, subdivided, combined, and / or modified to provide alternative or subcombinations. Each of these processes or blocks may be implemented in a variety of different ways. Also, while processes or blocks are at times shown as being performed in series, these processes or blocks may instead be performed in parallel, or may be performed at different times. 15

[0091] In addition, while elements are at times shown as being performed sequentially, they may instead be performed simultaneously or in different sequences. It is therefore intended that the following claims are interpreted to include all such variations as are within their intended scope.

[0092] Where a component is referred to above, unless otherwise indicated, reference to 20 that component (including a reference to a “means”) should be interpreted as including as equivalents of that component any component which performs the function of the described component (i.e. that is functionally equivalent), including components which are not structurally equivalent to the disclosed structure which performs the function in the illustrated exemplary embodiments of the invention. 25

[0093] Specific examples of systems, methods and apparatus have been described herein for purposes of illustration. These are only examples. The technology provided herein can be applied to systems other than the example systems described above. Many alterations, modifications, additions, omissions, and permutations are possible within the practice of this invention. This invention includes variations on described embodiments that would be 30 apparent to the skilled addressee, including variations obtained by: replacing features, elements and / or acts with equivalent features, elements and / or acts; mixing and matching CA 3301044 Date reçue / Received date 2026-02-05 18 of features, elements and / or acts from different embodiments; combining features, elements and / or acts from embodiments as described herein with features, elements and / or acts of other technology; and / or omitting combining features, elements and / or acts from described embodiments.

[0094] Various features are described herein as being present in “5 some embodiments”. Such features are not mandatory and may not be present in all embodiments. Embodiments of the invention may include zero, any one or any combination of two or more of such features. This is limited only to the extent that certain ones of such features are incompatible with other ones of such features in the sense that it would be impossible for a 10 person of ordinary skill in the art to construct a practical embodiment that combines such incompatible features. Consequently, the description that “some embodiments” possess feature A and “some embodiments” possess feature B should be interpreted as an express indication that the inventors also contemplate embodiments which combine features A and B (unless the description states otherwise or features A and B are fundamentally 15 incompatible).

[0095] While a number of exemplary aspects and embodiments have been discussed above, those of skill in the art will recognize certain modifications, permutations, additions and sub-combinations thereof. It is therefore intended that the following appended claims and claims hereafter introduced are interpreted to include all such modifications, 20 permutations, additions and sub-combinations as are consistent with the broadest interpretation of the specification as a whole. CA 3301044 Date reçue / Received date 2026-02-05

Claims

19 CLAIMS:

1. An apparatus for a top-drive drilling system, the apparatus comprising: a tubular gripping system comprising a main body, and a compression assembly comprising an actuator; wherein the main body is shaped to define a cavity for receiving 5 the actuator and the actuator is removably mountable to the main body inside the cavity for generation of compressive force applicable to a tubular.

2. The apparatus of claim 1 (or any other claim herein) further comprising a top drive 10 wherein the tubular gripping system is connected to the top drive and wherein the actuator is detachable from the main body and removable from the cavity while tubular gripping system is connected to the top drive.

3. The apparatus of claim 2 (or any other claim herein) wherein: 15 the top drive comprises a post which projects through a post-receiving opening defined in the main body and wherein a connection between the tubular gripping system and the top drive comprises a connection of the main body to the post; the cavity is shaped to provide a cavity opening through which the actuator is insertable into, and removable from, the cavity; and 20 the cavity opening is spaced apart from the post-receiving opening on the main body to facilitate insertion of the actuator into the cavity, and removal of the actuator from the cavity, through the cavity opening while the tubular gripping system is connected to the top drive. 25 4. The apparatus of claim 3 (or any other claim herein) wherein the cavity opening is oriented such that a direction of insertion of the actuator into the cavity and a direction of removal of the actuator from the cavity are generally aligned with (e.g. parallel to) a direction through which the post projects through the post-receiving opening. 30 5. The apparatus of any one of claims 1 to 4 (or any other claim herein) wherein the actuator comprises a hydraulic actuator comprising: CA 3301044 Date reçue / Received date 2026-02-05 20 a cylinder-defining member shaped to define a bore-defining surface that defines a cylinder bore; a piston shaped for reciprocal movement in an axial direction within the cylinder bore; and one or more seals located for slidable engagement between an 5 outer surface of the piston and the bore-defining surface.

6. The apparatus of claim 5 (or any other claim herein) wherein: an exterior surface of the cylinder-defining member comprises one or more 10 shoulders shaped to provide corresponding shoulder surfaces; the actuator is removably mountable to the main body inside the cavity by one or more plates which are couplable to the main body such that each of the one or more plates abuts against the exterior surface and against a corresponding one of the shoulder surfaces to retain the actuator within the cavity. 15 7. The apparatus of claim 6 (or any other claim herein) wherein each of the one or more plates is located in the cavity when coupled to the main body to abut against the exterior surface and against the corresponding one of the shoulder surfaces. 20 8. The apparatus of any one of claims 6 to 7 (or any other claim herein) wherein each of the one or more plates abuts against a portion of the exterior surface that provides a generally vertical face.

9. The apparatus of any one of claims 6 to 8 (or any other claim herein) wherein each 25 of the one or more plates abuts against a generally horizontally oriented shoulder face.

10. The apparatus of any one of claims 1 to 9 (or any other claim herein) wherein the cavity is enclosable by a panel. 30 11. An apparatus for a top drive drilling system, the system comprising: a tubular gripping system comprising a main body, and a compression assembly comprising an actuator; CA 3301044 Date reçue / Received date 2026-02-05 21 wherein the actuator is removably mountable to the main body for generation of compressive force applicable to a tubular.

12. The apparatus of claim 11 (or any other claim herein) further comprising a top drive, wherein the tubular gripping system is connected to the top drive 5 and wherein the actuator is removable from the main body while tubular gripping system is connected to the top drive.

13. The apparatus of claim 12 (or any other claim herein) wherein: 10 the top drive comprises a post which projects through a post-receiving opening defined in the main body and wherein a connection between the tubular gripping system and the top drive comprises a connection of the main body to the post; and the actuator is removably mountable to the main body at a location that is spaced apart from the post to facilitate removably mounting the actuator to the main 15 body without interference from the post.

14. The apparatus of claim 13 (or any other claim herein) wherein the main body is shaped to define a cavity for receiving the actuator and the actuator is removably mountable to the main body inside the cavity. 20 15. The apparatus of claim 14 (or any other claim herein) wherein: the cavity is shaped to provide a cavity opening through which the actuator is insertable into, and removable from, the cavity; and the cavity opening is spaced apart from the post-receiving opening on the main 25 body to facilitate insertion of the actuator into the cavity, and removal of the actuator from the cavity, through the cavity opening while the tubular gripping system is connected to the top drive.

16. The apparatus of claim 15 (or any other claim herein) wherein the cavity opening is 30 oriented such that a direction of insertion of the actuator into the cavity and a direction of removal of the actuator from the cavity are generally aligned with (e.g. parallel to) a direction through which the post projects through the post-receiving opening. CA 3301044 Date reçue / Received date 2026-02-05 22 17. The apparatus of any one of claims 15 to 16 (or any other claim herein) wherein the actuator comprises a hydraulic actuator comprising: a cylinder-defining member shaped to define a bore-defining surface that defines 5 a cylinder bore; a piston shaped for reciprocal movement in an axial direction within the cylinder bore; and one or more seals located for slidable engagement between an outer surface of the piston and the bore-defining surface. 10 18. The apparatus of claim 17 (or any other claim herein) wherein: an exterior surface of the cylinder-defining member comprises one or more shoulders shaped to provide corresponding shoulder surfaces; the actuator is removably mountable to the main body inside the cavity by one or 15 more plates which are couplable to the main body such that each of the one or more plates abuts against the exterior surface and against a corresponding one of the shoulder surfaces to thereby retain the actuator in the cavity.

19. A method of servicing a tubular gripping system for a top-drive drilling system, the 20 method comprising: detaching an actuator from a main body of the tubular gripping system while the main body is connected to a top drive of the top-drive drilling system; and removably mounting a second actuator to the main body while the main body is connected to the top drive. 25 20. The method of claim 19 (or any other claim herein) wherein: detaching the actuator from the main body comprises removing the actuator from inside of a cavity defined in the main body; and removably mounting the second actuator to the main body comprises inserting 30 the second actuator into the cavity and removably mounting the second actuator to the main body while the second actuator is located in the cavity.

21. The method of any one of claims 19 to 20 (or any other claim herein) wherein: CA 3301044 Date reçue / Received date 2026-02-05 23 the top drive comprises a post which projects through a post-receiving opening defined in the main body and wherein a connection between the tubular gripping system and the top drive comprises a connection of the main body to the post; detaching the actuator from the main body comprises detaching the actuator from a location that is spaced apart from the post to facilitate detaching 5 the actuator from the main body without interference from the post; and removably mounting the second actuator to the main body comprises removably mounting the second actuator to the main body at the location so spaced apart from the post to facilitate removably mounting the actuator to the main body without 10 interference from the post.

22. The method of claim 20 (or any other claim herein) wherein the top drive comprises a post which projects through a post-receiving opening defined in the main body and wherein a connection between the tubular gripping 15 system and the top drive comprises a connection of the main body to the post; removing the actuator from the inside of the cavity comprises removing the actuator in a removal direction that is generally aligned with (e.g. parallel to) a direction through which the post projects through the post-receiving opening; and inserting the second actuator into the cavity comprises inserting the actuator in 20 an insertion direction that is generally aligned with (e.g. parallel to) the direction through which the post projects through the post-receiving opening.

23. The method of any one of claims 19 to 22 (or any other claim herein) wherein: the second actuator comprises a hydraulic actuator comprising: a cylinder25 defining member shaped to define a bore-defining surface that defines a cylinder bore; a piston shaped for reciprocal movement in an axial direction within the cylinder bore; and one or more seals located for slidable engagement between an outer surface of the piston and the bore-defining surface; and an exterior surface of the cylinder-defining member comprises one or more 30 shoulders shaped to provide corresponding shoulder surfaces; and removably mounting the second actuator to the main body comprises: coupling one or more plates to the main body such that each of the one or more plates abuts CA 3301044 Date reçue / Received date 2026-02-05 24 against the exterior surface and against a corresponding one of the shoulder surfaces to thereby mount the second actuator to the main body.

24. Apparatus having any new and inventive feature, combination of features, or sub combination of features as 5 described herein.

25. Methods having any new and inventive steps, act, combination of steps and / or acts or sub-combination of steps and / or acts as described herein. 10 CA 3301044 Date reçue / Received date 2026-02-05