This application claims the benefit of priority of Canadian Patent Application No. 3,085,090 filed Jun. 29, 2020, which is incorporated herein by reference.
The invention pertains generally to oil and gas production. More specifically, the invention relates to a torque stopper device for preventing rotation of a tubing string or progressive cavity pump in the bore of a casing string.
Oil is often pumped from a subterranean reservoir using a progressive cavity (PC) pump. The stator of the PC pump is threaded onto the bottom of a long assembled string of section tubing. A rod string extends downhole and drives the PC pump rotor. Large reaction or rotator rotational forces can cause the tubing or PC pump stator to unthread, resulting in loss of the pump or tubing string.
Anti-rotation tools with a pivotable jaw (also sometimes referred to as a pivotable door) are described, for example, in Canadian Patent No. 2,264,467 entitled “DOWNHOLE ANTI-ROTATION TOOL”, Canadian Patent No. 2,373,734 entitled “DOWNHOLE ANTI-ROTATION TOOL”, and Canadian Patent No. 2,386,026 entitled “IMPROVED ANTI-ROTATION TOOL”. These tools are commonly referred to as torque stopper devices and/or torque anchor devices.
Complete details of the operation of the torque stopper device 100 and jaw 102 are found in the above-mentioned prior art patents; however, their operation can be briefly described as follows.
When the torque stopper 100 is rotated counterclockwise (as viewed from the surface looking down the wellbore), the jaw 102 is pivoted toward a stowed position where it pivots toward the housing 104 of the torque stopper body 100 and does not interfere with rotation. In this way, the sectional tubing down the wellbore can freely be rotated in the counterclockwise direction. However, when the torque stopper 100 is rotated in the clockwise direction, the jaw 102 is pivoted away from the torque stopper body 100 into a deployed position as shown in
To successfully achieve the desired goal of stopping rotation in the clockwise direction, care must be taken to ensure that the diameter of the tubular body of the torque stopper 100 combined with the length of the jaw 102 in the deployed position (which may be either a partially or fully extended) is sufficient to catch the radial tip 106 on the casing and jam (i.e., stop) the rotation. If the combined width of the torque stopper body 100 and jaw 102 in the fully extended position is less than the internal diameter of the casing, the torque stopper device 100 will be unable to prevent rotation. However, if the jaw 102 is too long such that the combined width is much greater than an ideal threshold width, the torque stopper device 100 will again be unable to prevent rotation because the jaw 102 will simply not be able to pivot enough such that the radial tip 102 can properly catch the casing wall. The tip 106 may catch partially, but the hold will not be solid and failure may later occur due to vibrations of the PC pump.
In other words, to ensure proper operation, the size of the torque stopper 100 and accompanying jaw 102 must be selected in dependence upon the casing outer diameter size and also the casing weight. Casing outer diameter directly affects the inner diameter, and higher casing weight also affects the inner diameter because larger weight equates to thicker casing walls thereby reducing the inner diameter.
The following table provides an example of an ordering document utilized to select a model of the torque stopper tool 100 (i.e., “Tool model”) given a particular casing outer diameter (“Csg O.D.”), casing weight (“Csg Wt”), and thread connection size. Each different tool model number has a different sized jaw/door with a note shown in the last column that some casing parameters require further special jaw/door changes for even a same tool model as listed in the below table.
14-19.5
45-60.7
One problem with the current prior art torque stopper devices 100 with pivotable jaws 102 is that the selection of parts is time consuming and confusing. Even for trained individuals, it is possible that wrongly sized parts may be selected and utilized in wellbore where the casing internal diameter leads to the tool 100 not working well. In this event, the torque stopper device 100 may prevent downhole tool rotation for a period of time and then fail. The reason for failure may not be apparent to people working on site and replacement parts may be installed with the same incorrectly sized components.
Another problem with the current prior art torque stopper devices 100 is availability of properly sized parts. Although many countries utilize standard casing sizes and weights, the sizes are not universal. For example, seven-inch casing may have a range of weights from 17 lbs/ft all the way to 32 lbs/ft. In some cases, cheaper casing may be available with non-standard sizes. To give some examples, Canada uses 7.0″×17#−26# casings, and Colombia uses −7.0″×22#−26# and 7.0″×26#−29# casings. Colombia also has 7.0″×32# casings, but, as shown in the above chart, there is simply no available combination of tool 100 and jaw/door 102 size that will accommodate such casing OD and weight. As shown by these examples, there are many different sized doors/jaws required just for 7.0″ casings.
According to an exemplary embodiment of the invention there is disclosed a multi-tooth jaw for a torque stopper device preventing rotation of one or more downhole tools suspended in a wellbore casing. The multi-tooth jaw includes a base for positioning adjacent an outside wall of the torque stopper device and a hinge connection on the base for joining with a corresponding hinge connection on the outside wall of the torque stopper device to thereby allow the multi-tooth jaw to pivot around an axis of rotation running lengthwise through the base. The multi-tooth jaw further includes a plurality of radial tips each extending laterally from the base a different distance from the axis of rotation.
According to an exemplary embodiment of the invention there is disclosed a torque stopper device comprising a multi-tooth jaw as disclosed herein.
According to another exemplary embodiment of the invention there is disclosed a repair kit for a torque stopper device, the repair kit including a multi-tooth jaw as disclosed herein.
According to yet another exemplary embodiment of the invention there is disclosed a method of utilizing the repair kit to replace a prior art one-tooth jaw of a torque stopper device with a newer multi-tooth jaw as disclosed herein.
These and other advantages and embodiments of the present invention will no doubt become apparent to those of ordinary skill in the art after reading the following detailed description of preferred embodiments illustrated in the various figures and drawings.
The invention will be described in greater detail with reference to the accompanying drawings which represent preferred embodiments thereof:
As illustrated, the multi-tooth jaw 500 includes an elongated base 502 with hinge pin holes 504 on either side for insertion of hinge pins (not shown). An axis of rotation runs 506 lengthwise through the base 502, and the base 502 has a rounded bottom 508 with a stopper ledge 510 for impacting a corresponding stopper ledge on the body of the torque stopper device 550 to prevent over rotation of the jaw 500 past a threshold angle such as ninety degrees from the housing wall 552 (see
Where the jaw 500 of
An inner side 524 of the jaw 500 that will lie against the outside housing wall 552 of the torque stopper device 550 while the jaw 500 is pivoted to a fully stowed position has a concave shape. The concave shape helps the jaw 500 stay close to the housing wall 552 and reduce the combined width of the torque stopper device 550 with jaw 500 in the stowed position. Likewise, an outer side 526 of the jaw 500 facing the wellbore casing while the jaw is pivoted in the stowed position has a convex shape. The slight convex shape again helps the outside of the jaw 500 follow the shape of the torque device body when the jaw 500 is in the stowed position. This arcuate shape of the jaw 500 can help the jaw 500 in the stowed position from interfering with rotation of the tool string in the counterclockwise direction.
In some embodiments, a spring (not shown) within the hinge joints by the hinge pin holes 504 where the jaw joins to the torque stopper body 551 (see
As shown in
In some embodiments, a repair kit is provided to allow operators to replace the prior art jaw 102 when the tool string is removed from the wellbore for maintenance. This may be done routinely in the field whenever the torque stopper device 100 is extracted from the wellbore. The repair kit may include all the required parts such as mounting blocks 554 and a multi-tooth jaw 500 as disclosed herein. A method of utilizing the repair kit includes firstly removing the pre-existing jaw on the torque stopper device 100, which may be a single-tooth jaw 102 according to the prior art as illustrated in
Having a multi-tooth jaw 500 as disclosed herein has several advantages over the single-tooth jaw 102 of the prior art. To facilitate an understanding of advantages of certain embodiments,
The example of
As illustrated in
In many situations, multiple teeth 522 will engage the casing wall 700 providing a stronger engagement. Moreover, in the event a leading tooth 522a breaks, the following teeth 522b,c (at longer distances from the axis of rotation 506 of the jaw 500) may still catch. Failures are thus prevented at greater ranges of internal diameter casing 700 when compared to a single-tooth jaw 102. In yet another benefit of some embodiments, multi-teeth jaws 500 as disclosed herein can be fully compatible with existing torque stopper device bodies 100 and associated mounting blocks 554. Thus, existing single-tooth jaws 102 can easily be replaced with a multi-tooth jaws 500 as disclosed herein in the field. A repair kit may provide all the required parts to replace the old jaw 102 with a new multi-tooth jaw 500 thereby increasing the effectiveness and reliability of an existing torque stopper device 100.
According to an exemplary embodiment, a multi-tooth jaw 500 for a torque stopper device 550 prevents rotation of downhole tools suspended in a wellbore casing 700. The jaw 500 includes a base 502 for positioning adjacent an outside wall 552 of the torque stopper body 551 and a hinge connection 504 allowing the jaw 500 to pivot around an axis of rotation 506 running lengthwise through the base 502. The jaw 500 further includes a plurality of radial tips 522, i.e., teeth, each a different distance, e.g., R1, R2, R3, from the axis of rotation 506. When viewed from a side with the axis of rotation 506 being a point around which the jaw 500 pivots, the tips 522 are in ascending order of distance with a first, leading tip 522a having a shortest distance R1 from the axis of rotation 506 as the jaw 500 pivots from a stowed to a deployed position. A torque stopper device 550 with the multi-tooth jaw 500 supports a range of casing 700 internal diameters. A repair kit allows swapping a prior art, one-tooth jaw 102 with the multi-tooth jaw 550, 500.
Although the invention has been described in connection with preferred embodiments, it should be understood that various modifications, additions and alterations may be made to the invention by one skilled in the art without departing from the spirit and scope of the invention.
Although a multi-tooth jaw 500 having three radial tips 522a,b,c (i.e., three teeth) has been disclosed herein and supports a good range of casing 700 internal diameters, other embodiments are also possible. For example, a multi-tooth jaw may be formed similarly utilizing a plurality of only two radial tips 522a,b at different distances R1, R2 from the axis of rotation 506. Likewise, a multi-tooth jaw 500 in some embodiments may include four (or more) radial tips 522, each at different distances from the axis of rotation 506.
In some embodiments, regardless of the number of teeth (i.e., radial tips 522), the tips 522 may be ordered in ascending order of distance from the axis of rotation 506 such that a leading tip 522a when the jaw 500 is pivoting from stowed to deployed position has the shortest distance R1 to the axis of rotation 506. In this way, the first, leading tooth 522a can catch the casing 700 side when the casing internal diameter is small and the later teeth 522b+ are each at progressively larger distances such that they will catch the casing 700 side when the jaw 500 pivots outwards further in the event the casing 700 internal diameter is larger. However, in other embodiments, multiple radial tips 522 at a same distance from the axis of rotation 506 are provided on the jaw 500. Having multiple teeth 522 at a single level may act as a redundancy in the event one of the radial tips breaks 522 or wears down. Furthermore, having multiple teeth 522 catch the casing 700 at a same time can beneficially avoid the forces of the torque stopper disforming (i.e., “egging”) the shape of the casing 700. This benefit applies regardless of whether the multiple teeth 522 that simultaneously catch the casing 700 are at different levels on the jaw 500 or at the same level.
Single elements may be separated into multiple elements, or multiple elements may be combined into a single elements. For example, in some embodiments, the radial tips 522 and the jaw body 512 may be combined into a single, integral unit. In some embodiments, the radial tips 522 are formed by the material of the jaw body 512 rather than utilizing tungsten carbide inserts 520 soldered in valleys 516. Other types of strong materials besides tungsten carbide may be utilized to form the radial tips 522.
All combinations and permutations of the above described features and embodiments may be utilized in conjunction with the invention.
Number | Date | Country | Kind |
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3085090 | Jun 2020 | CA | national |