ATING BREAKING OUT A THREADED PIPE CONNECTION

The present disclosure is related to a wrench apparatus. More particularly, the disclosure is related to a wrench apparatus and a method for facilitating finalizing making up and initiating breaking out a threaded connection between a first pipe and a second pipe.

The wrench apparatus is primarily an auxiliary tool for use when for example a common rotary tool fails in achieving a sufficient torque required to finalizing making up or initiating breaking out a threaded pipe connection. It should be noted that the intention or purpose of the wrench apparatus according to the invention is not to provide a complete make-up or a complete break-out for a threaded pipe connection. For example, a drill-string in the petroleum industry is made up of a plurality of pipe sections screwed together by means of an iron roughneck connected to a top-drive drilling machine of a drilling rig.

When a top-drive drilling machine is used, for example in exploration and production drilling for oil and gas, one or more subs with varying functions are arranged between a driveshaft of the drilling machine and the drill string. A sub may function solely as a replaceable wear part for the threads of the driveshaft not to become ruined by constantly being connected and disconnected. Such a sub may stay connected to the driveshaft until it must be replaced because of wear, or when changing a diameter of the drill pipes. Another type of sub may include safety valves for controlling the fluid pressure in the drill string, typically one or more so-called IBOPs (Internal Blowout Preventers). Such a sub must be disassembled regularly for a required valve check. Because of adjacent elements, for example frame details, ordinary pipe tongs which are used for making up and breaking out pipe sections have a reach which makes it impossible for them to be used to remove and fit said subs, as the drilling machine will hit the tongs before the jaws of the tongs encircle the sub. For the removal and fitting of subs of this kind it is therefore common to position a separate pair of rigging tongs provisionally around the sub, for instance by means of a lifting device (a winch or the like) and a stack of pallets. This work involves a significant risk of injury to personnel working in the red zone on rig floor, and the operation is time-consuming and thereby expensive, as the drilling will have to be stopped during this period.

Publication NO 333414 to the applicant discloses a tool for mounting a subs assembly on the driveshaft of a top-drive drilling machine, in which, by releasable abutment against a portion of the subs assembly, a pair of tongs arranged to hold the subs assembly fixed is arranged on an upper portion of a frame which, in a position of application, is fixed in a rotationally rigid manner to and projects from a base, the frame being provided with a through centre opening arranged to receive a substantial portion of the subs assembly, characterized by the centre opening extending, in the position of application of the main frame, through an opening in the base. The drawback of this solution is that a connected top-drive drilling machine will have to be put in operation to break out the subs assembly, which is to be replaced, from the driveshaft of the drilling machine.

Publication WO 2016/099286 to the applicant discloses an apparatus for making up and breaking out a threaded connection in a subs assembly connected to the driveshaft of a top-drive drilling machine. The apparatus comprises a main frame, which in a position of application is rotationally rigidly fixed to and projects up from a base. The main frame is provided with a centre opening arranged to receive the subs assembly. The apparatus further comprises a first clamping device arranged in an upper portion of the main frame and configured to hold the subs assembly fixed in the centre opening by releasable abutment against a portion of the subs assembly. A second clamping device is arranged at a distance from the first clamping device, rotatable over a sector around the centre axis in the centre opening of the main frame. The apparatus disclosed in WO 2016/099286 has proven to function satisfactorily for making up and breaking out a threaded connection in a subs assembly connected to the driveshaft of a top-drive drilling machine. However, there is a need for a more versatile apparatus that may for example be utilized on a rotary table of a drilling rig, over a drillpipe stickup secured by a slips, and even in a horizontal position to, for example, break over-torqued bottom hole assembly (BHA).

Publication US 2013/0255965 A1 discloses a break out wrench assembly comprising a first subassembly a first pair of opposing arms linked by a first actuator configured to extend or compress a distance between the first pair of opposing arms; and a second subassembly aligned with the first subassembly to receive a longitudinal member therebetween and rotate axially along the longitudinal member in relation to the first sub- assembly, the second subassembly comprising a second pair of opposing arms linked by a second actuator configured to extend or compress another distance between the second pair of opposing arms; and at least one axial actuator coupled to the second subassembly and configured to rotate the second subassembly axially in relation to the first subassembly along the longitudinal member.

The invention has for its object to remedy or to reduce at least one of the drawbacks of the prior art, or at least provide a useful alternative to prior art.

The object is achieved through features, which are specified in the description below and in the claims that follow.

The apparatus according to the present invention is a versatile tool that can be configured for various operations and adapted to initiate breaking out and finalize making up threaded connections.

The invention is defined by the independent patent claims. The dependent claims define advantageous embodiments of the invention.

In a first aspect the invention there is provided there is provided a torque wrench apparatus for facilitating finalizing making up and initiating breaking out a threaded connection between a first pipe and a second pipe, the apparatus comprises:

- a first wrench portion comprising:

- a body having a through-bore for extending between a first surface and a second surface, the through-bore configured for, in a position of use, enclosing a portion of the first pipe,

- an engagement means for preventing relative rotation between the first wrench portion and the first pipe;

- at least one actuator secured to and tangentially movable with respect to a periphery portion of the first wrench portion between a retracted first position and an extended second position, wherein an end portion of the actuator comprises an actuator connection device.

The wrench apparatus further comprises a second wrench portion comprising:

- a through-bore extending between a first surface and a second surface opposite the first surface, the through-bore configured for, in a position of use, enclosing a portion of the second pipe; and,

- an engagement means for preventing relative rotation between the second wrench portion and the second pipe, wherein the second surface of the second wrench portion faces the first surface of the first wrench portion, and wherein the second wrench portion is detachably secured to the first wrench portion (3) via connecting means securing the second wrench portion to the actuator connection device of the actuator of the first wrench portion, so that, when activating the actuator, the second wrench portion is rotated a sector with respect to the first wrench portion to allow finalizing making up or initiating breaking out threadedly connected first and second pipes being in engagement with the first wrench portion and the second wrench portion, respectively.

Preferably, the wrench apparatus is operatively connected to a control system known per se, for controlling the at least one torque actuator and any engagement means.

The at least one torque actuator may typically be hydraulically operated. In a prototype of the wrench apparatus according to the invention, the first wrench portion was provided with two hydraulically operated actuators for providing relative rotation between the first and second wrench portions. A maximum break-out torque was about 300.000 Nm (221.000 lbs/ft.), and a maximum make-up torque was about 170.000 Nm (125.400 Ibs/ft.)

By securing the at least one actuator to the first wrench portion and operatively connecting the second wrench portion to the actuator, the second wrench portion may be regarded as a “passive” portion that is controlled by the first wrench portion carrying the at least one actuator for effecting the relative rotation between the first- and second wrench portions. One effect of providing a “passive” second wrench portion is that the second wrench portion may be provided as a replaceable portion of the apparatus to allow a variety of configurations of the apparatus using the same at least one actuator. A requirement to provide the desired relative rotation between the first- and second wrench portions is that the second wrench portion connecting means fits with the actuator connection device of the actuator.

The actuators for operating the dices may be selected from the group consisting of fluid operated actuators, such a pneumatically or hydraulically operated actuators, or actuators comprising an electric motor; or a combination thereof.

A pipe portion to be engaged by the second wrench portion, may typically be provided with a smooth surface. To hold the second pipe portion against rotation, the engagement means of the second wrench portion may comprise at least two dices being radially mov- able from an inactive, non-gripping position to an active, gripping position wherein, in operation, the dices abut against a surface of the second pipe to prevent relative rotation between the second wrench portion and the second pipe. In one embodiment are the dices provided with a serrated gripping surface.

However, instead of smooth surface as discussed above, a pipe portion to be engaged by the second wrench portion, may be provided with a spline portion. A spline portion may be vulnerable to damages. To at least reduce such damages to a spline portion of a pipe to be held against rotation by the second wrench portion, the engagement means of the second wrench portion may be provided with splines configured for mating splines of the second pipe to prevent relative rotation between the second wrench portion and the second pipe.

In one embodiment of the invention, is the engagement means of the second wrench portion formed by splines forming part of the through-bore, wherein the splines are configured for mating splines of the second pipe to prevent relative rotation between the second wrench portion and the second pipe. This has the effect that the second wrench portion may be configured without any movable parts, while at the same time providing a secure engagement with the splines of the second pipe without damaging the splines of the second pipe.

Independently of the configuration of the second wrench portion, the engagement means of the first wrench portion may comprise at least two dices being radially movable from an inactive non-gripping position to an active, gripping position wherein, in operation, the dices are configured to abut against a surface of the first pipe to prevent relative rotation between the first wrench portion and the first pipe. The at least two dices may be provided with a splined gripping surface. A splined gripping surface of the dices will prevent damage to a first piping provided with a splined surface.

As discussed above, the threaded engagement between the first pipe portion and the second pipe portion may be provided by a rotating machine such as for example, but not limited to a top drive drilling machine. In such a situation, when the wrench apparatus is in the position of application, the second wrench portion may be arranged closer to a drilling machine than the first wrench portion. Thus, the second wrench portion may form a top portion of the wrench apparatus according to the invention. Providing the second wrench portion as a top portion may facilitate adaption of the apparatus to desired need even after the apparatus is in a position of application. However, as will be discussed below, the wrench apparatus may also be configured for operation in a substantially horizontal position, or in an inclined position.

The first wrench portion of the wrench apparatus has, as stated above, a first surface facing the second wrench portion, and a second surface opposite the first surface, the apparatus may further comprise a transition element having a top portion abutting against the second surface, and a bottom portion secured to a base. The transition element may be a sub stem configured for supporting the wrench apparatus in a rotationally rigid engagement with a portion at an opening in the base, typically around the centre opening of a rotary table arranged in a drill floor of a drilling rig. Preferably, such a sub stem is detachable from the wrench apparatus. Thus, a transition element for example in the form of a sub stem may be an adapter plate for being placed with a clearance on top of slips. The first wrench portion and the second wrench portion of the apparatus are provided with a through-bore, as mentioned above. By providing a transition element also having through- bore, the wrench apparatus may be arranged to enclose a so-called stick up of for example a drill pipe, and break out for example an over-torque connection that cannot be disconnected by for example so-called rig tongs or IRN (Iron Roughneck) which are known to a person skilled in the art.

In a position of use, the wrench apparatus may be arranged so that a longitudinal axis of the through-bore of the first wrench portion and the through-bore of the second wrench portion is one of: vertical, horizontal, or inclined. When the apparatus is used in connection with for example a drill-string in the petroleum industry wherein a plurality of pipe sections are screwed together by means of a top-drive drilling machine of a drilling rig, the longitudinal axis of the through-bore of the first wrench portion and the through-bore of the second wrench portion of the apparatus is substantially vertical. However, when the apparatus is used for example for breaking an over-torqued bottom hole assembly, the apparatus is typically arranged with the longitudinal axis of the through-bore of the first wrench portion and the through-bore of the second wrench portion being substantially in parallel with a rig floor. A rig floor may be horizontal or, for a floating rig, periodically inclined.

The apparatus may be supported by a cradle movable on a track. Supporting the apparatus by a cradle movable on a track makes the apparatus flexible with respect to an operation position of the apparatus. The pipes to be finalized made up or break out by the apparatus, may be kept stationary in the meaning that the apparatus itself is moved to the relevant pipe joint, and not the other way round. In one embodiment, the cradle is further configured for carrying a rotating machine. Since the first wrench portion and the second wrench portion are each configured for preventing relative rotation with respect to gripped first pipe and the second pipe respectively, the apparatus does not have to be rotationally secured to the cradle.

In the embodiment wherein the apparatus is operatively connected to a cradle movable on a track, the track may be secured to a base of a transport container. The transport container may for example be a so-called basket commonly used in the petroleum industry for transporting pipes to and from for example a drilling rig. By arranging the apparatus in a transport container, a transport of the apparatus between various locations, such as various locations on a rig, or between rigs, is facilitated.

Preferably, the transport container may be provided with pivotable wall portions that are hingedly connected to a periphery portion of a base of the container. An effect of providing the transport container with pivotable wall portions is that access for an operator to and from the apparatus is facilitated. Easy access represents an important safety aspect.

In a second aspect the invention there is provided a method for facilitating finalizing making up or initiating breaking out a threaded connection between a first pipe and a second pipe, the method comprising: a) providing a wrench apparatus according to the first aspect of the invention; b) bringing the first wrench portion into engagement with a portion of the first pipe, and the second wrench portion into engagement with a portion of the second pipe threadedly connected the first pipe; c) activating the at least one actuator to provide a relative rotation between the first wrench portion and the second wrench portion over a sector to finalize making up or initiating breaking out the threaded connection between the first pipe and the second pipe.

When the method is related to breaking out a threaded connection, the method further may comprise after step c): d) disengaging the wrench apparatus from engagement with the first pipe and the second pipe and thereafter removing the wrench apparatus from the first pipe and the second pipe; and e) providing relative rotation between the first pipe and the second pipe by means of a rotating machine to disengage the threaded connection between the first pipe and the second pipe.

When the method is for finalizing making up of a threaded connection, the method may comprise prior to step b): f) bringing a rotating machine into engagement with one of the first pipe and the second pipe while the other one of the second pipe and the first pipe is prevented from rotation; g) activating the rotating machine to provide the threaded connection between the first pipe and the second pipe, and; h) when a predetermined torque is achieved, deactivating the rotating machine.

From the above it should be clear that the wrench apparatus and the method according to the present invention is for finalizing making up and initiating breaking out a threaded connection between a first pipe and a second pipe, and the apparatus is an auxiliary tool for use in special situations wherein a rotating machine commonly used for making up or braking out a threaded connection between a first pipe and a second pipe cannot be used, or when it is desired to avoid using such a common rotating machine due to a torque required.

In the following is described examples of preferred embodiments illustrated in the accompanying drawings, wherein:

Figs. 1 a-1 e show a first embodiment of a wrench apparatus according to the present invention;

Figs. 2a-2e show a second embodiment of a wrench apparatus according to the present invention;

Fig. 3a shows in a smaller scale a basket comprising the apparatus according the first aspect of the invention, for facilitating finalizing making up and initiating breaking out a threaded connection for pipes being in a substantially horizontal position;

Fig. 3b shows in a larger scale a detail of the apparatus shown in fig. 3a;

Fig. 4a shows a detail of a cradle configured for carrying i.a. the apparatus shown in fig. 3b; and

Fig. 4b shows in a larger scale a detail of a pipe support apparatus arranged at an end portion of the basket shown in fig. 3a.

Any positional indications refer to the position shown in the figures. In the figures, same or corresponding elements are indicated by same reference numerals. For clarity reasons some elements may in some of the figures be without reference numerals.

A person skilled in the art will understand that the figures are just principle drawings. The relative proportions of individual elements may be distorted.

In the figures reference numeral 1 denotes a wrench apparatus according to the invention. The wrench apparatus 1 will hereinafter also be denoted torque wrench 1 , or simply apparatus 1 . The apparatus 1 is configured for facilitating finalizing making up and initiating breaking out a threaded connection between a first pipe P1 and a second pipe P2 being in engagement each other.

The apparatus 1 comprises a first wrench portion 3, and a second wrench portion 5 operatively connected to the first wrench portion 3. The apparatus 1 is operatively connected to a control system (not shown) known to a person skilled in the art.

The first wrench portion 3 comprises a through-bore 31 for, in a position of use, enclosing a portion of the first pipe P1 (shown in fig. 2e only), and an engagement means 33 for preventing relative rotation between the first wrench portion 3 and the first pipe P1 . In the embodiments shown, the engagement means is in the form of dices 33 radially displaceable with respect to a center axis of the through-bore 31 of the first wrench portion 3.

Each dice 33 is radially moveable by means of a corresponding dice actuator 45 (four shown) between a passive, non-gripping position wherein a gripping surface 33’ of each dice 33 does not protrude beyond the surface of the bore 31 , and an active, gripping position wherein the gripping surface of each dice 33 protrudes beyond the surface of the bore 31 , i.e., towards a center of the bore 31 . Even if the dices 33 are shown fully retracted in a dice housing 331 of the first wrench portion 3 when in the passive, non-gripping position, it should be emphasized that a minor portion of the dices 33 may alternatively protrude from said dice housing 331 when in the passive, non-gripping position.

In the embodiments shown, the first wrench portion 3 comprises two torque actuators 4 secured to a respective frame 35 extending radially outwards from a body 37 of the first wrench portion 3. As best seen in figures 1d and 2d, the two frames 35 extend diametrically with respect to a longitudinal axis L of the through-bore 31 of the first wrench portion 3.

A portion of the torque actuators 4 are substantially tangentially movable with respect to a periphery portion of the first wrench portion 3, between a retracted first position as shown, and an extended second position (not shown). The torque actuators 4 further comprises an actuator connection device, here in the form of an annular element 41 secured to an end portion of the torque actuator 4 being movable with respect to the frame 35 between said retracted first position and extended second position.

Like the first wrench portion 3, the second wrench portion 5 comprises a through-bore 51 for, in a position of use, enclosing a portion of a second pipe P2 (shown in figures 2a-2e) configured for being threadedly connected to the first pipe P1 , and an engagement means 53 for preventing relative rotation between the second wrench portion 5 and the second pipe P2. For the purpose of illustrating a feature of the second embodiment of the invention, the first pipe P1 is in figures 2a-2e shown axially distant from the second pipe P2. However, it should be noted that the apparatus 1 according to the invention is activated to facilitate finalizing making up or initiating breaking out a pipe connection that has already been made by means of a rotary machine as will be explained below.

The second wrench portion 5 further comprises connecting means 54 for securing the second wrench portion 5 to the actuator connection device 41 of the torque actuator 4. In the embodiments shown, the connecting means is in the form of two circular rods 54 secured to arms 58 extending radially from a body 57 of the second wrench portion 5. In a position of use of the apparatus 1 , the circular rods 54 are secured to the annular element 41 of the torque actuator 4 and detachable therefrom in a manner known per se.

When activating the torque actuator 4 from one of the retracted first position or the extended second position, the second wrench portion 5 is rotated a sector with respect to the first wrench portion 3 to allow finalizing making up or initiating breaking out already threadedly connected first and second pipes P1 , P2 being in engagement with the first wrench portion 3 and the second wrench portion 5, respectively. In the embodiments shown are the torque actuators 4 in the retracted first position, meaning that an angle between longitudinal axes of the frames 35 and the arms 58, is at a minimum.

Turning now to figures 1a - 1e showing a first embodiment of the apparatus 1 according to the invention. In the first embodiment, the second wrench portion 5 have similarities with the first wrench portion 3, in that the engagement means 53 are provided by means of dices 53 radially displaceable with respect to a center axis of the through-bore 51 of the second wrench portion 5.

Each dice 53 is radially moveable by means of a corresponding dice actuator 55 (four shown) between a passive, non-gripping position wherein a gripping surface 53’ of each dice 53 does not protrude beyond the surface of the bore 51 , as shown, and an active, gripping position wherein the gripping surface of each dice 53 protrudes beyond the surface of the bore 51 , i.e., towards a center of the bore 51 . Even if the dices 53 are shown fully retracted in a dice housing 553 of the second wrench portion 5 when in the passive, non-gripping position, it should be emphasized that a minor portion of the dices 53 may alternatively protrude from said dice housing 553 when in the passive, non-gripping position.

Turning now to figures 2a - 2e showing a second embodiment of the wrench apparatus 1 wherein a surface of the through-bore 51 of the second wrench portion 5 is provided with a spline 52 configured for mating with a splined surface 252 of the second pipe P2. Thus, in the embodiment shown, the engagement means of the second wrench portion 5 is a spline 52.

In a position of use, the second wrench portion 5 rests against a supporting disc 60 secured to and protruding from a first surface 36 of the body 37 of the first wrench portion 3. A main purpose of the supporting disc 60 is to provide a clearance between a portion of the first surface 36 of the first wrench portion 3 and a second surface 56’ of the second wrench portion 5 abutting said first surface 36.

In figures 1 a- 1 e the dices 33 of the first wrench portion 3 has a corrugated gripping surface 33’ (as indicated in fig. 2e) configured for, in a position of use, engaging a surface portion of the first pipe P1 . Similarly, the dices 53 of the second wrench portion 5 has a corrugated gripping surface 53’ configured for, in a position of use, engaging a surface portion of the second pipe P2.

The dices 33 of the first wrench portion 3, and the dices 53 of the second wrench portion 5, are replaceable to mate with the pipes P1 and P2, respectively, to be handled by means of the apparatus 1 . The dices 33, 53 may be connected to their respective dice actuators 45, 55 for example by means of dovetails (not shown). Upon replacement of the dices 33, 53, the dices 33, 53 are urged out of dice housings 331 , 553, respectively, and slid out of the dovetails.

In some cases, the pipes P1 and P2 to be finalized made up or initiated for break out may comprise splines in the portion to be engaged by the first wrench portion 3 and the second wrench portion of the apparatus. 1 . An example of pipes that may comprise such splines, are pipes configured for a top drive provided by the company National Oilwell Varco (NOV).

The dices 33, 53 provided with corrugated gripping surfaces 33’ shown in figures 1 e, may damage such splines. To avoid such damage, the first wrench portion 3 and the second wrench portion 5, may be provided with engagement means in the form of splines 33 as shown in figures 2a - 2e illustrating an example of the second embodiment of the invention.

In figures 2a - 2e, the first wrench portion 3 has a substantial similar configuration as illustrated in figures 1 a - 1 e. However, as best seen in fig. 2e, the dices 33 are provided with splines 33’ instead of the corrugated surface as shown in fig. 1e. The splines 33’ are configured for mating with corresponding splines (not shown) arranged on an outer surface of the first pipe P1. Further, for clarity, the threads arranged on the outer surface of the male part of the second pipe P2, and the corresponding threads on the inner surface of the first pipe P1 are neither shown.

Thus, since the only difference between the first wrench portion 3 shown in figures 1 a - 1 e, and in the figures 2a - 2e, is the surface configuration of the engagement means 33 shown as dices, the first wrench portion 3 may be adapted to desired needs simply by replacing the engagement means 33. Similarly, the engagement means 53 of the second wrench portion 5 may be provided by means of dices 53 provided with splines 53’ mating with splines 252 on an outer surface of the second pipe portion P2.

However, in situation wherein the second pipe P2 is provided with splines 252 as illustrated in figures 2a-2e, the required engagement between the second wrench portion 5 and the second pipe P2 may be provided by mating splines 52 arranged in a surface of the through-bore 51 of the second wrench portion 5 as shown in fig. 2e.

The embodiments discussed above indicates that the apparatus 1 can be adapted to a variety of applications, simply by providing a second wrench portion 5 configured for desired needs.

Turning now to figures 3a and 3b illustrating the apparatus 1 according to the invention configured for facilitating finalizing making up and initiating breaking out a threaded connection between a first pipe P1 and a second pipe P2. In the embodiment shown, the apparatus 1 corresponds to the apparatus shown in figures 1 a-1 e, but arranged so that the bores 31 , 51 of the first wrench portion 3 and the second wrench portion 5, respectively, has longitudinal axes L being substantially horizontal. The first pipe P1 and the second pipe P2 are carried in a substantially horizontal position by means of cradles 100, 105, and rotating machine R carried by the cradle 105. The cradles 100, 105 and thus the rotating machine R, are movable along a track 110. After connecting the pipes P1 , P2 by means of the rotating machine R, the apparatus 1 may be activated for finalizing making up of the connection. The apparatus 1 may also be used for initiating breaking out a threaded connection between the pipes P1 , P2, whereupon the pipes are separated by means of the rotating machine R.

In the embodiment shown, cradles 100, 105 supporting the pipes P1 , P2 and the rotating machine R, are movable along a track 110 arranged in a bottom portion of a so-called basket 150 commonly used in the petroleum industry for transporting pipes to and from for example a drilling rig. In the embodiment shown, the basket 150 is provided with pivotable wall portions 152 that are hingedly connected to a periphery portion of a base of the basket 150.

The rotating machine R and the apparatus 1 according to the invention are carried by the common cradle 105 that are shown in larger scale in fig. 4a. The common cradle 105 is operatively connected to a driving means for moving the common cradle 105 along the track 110. The driving means is in the embodiment shown a rack and pinion arrangement 112.

Fig. 4b shows in larger scale the cradle 100 to the left of the basket 150 shown in fig. 3a. The cradle 100 is provided with a pair of rollers 102 for facilitating rotation of the pipe P2 by means of the rotating machine R. The cradle 100 is moveable along the track 110.

It should be noted that the above-mentioned embodiments illustrate rather than limit the invention, and that those skilled in the art will be able to design many alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. Use of the verb "comprise" and its conjugations does not exclude the presence of elements or steps other than those stated in a claim. The article "a" or "an" preceding an element does not exclude the presence of a plurality of such elements.