Abstract
A fall arrest safety system for overhead rotating tools includes a tether ring assembly having an inner ring and an outer ring. The inner ring clamps onto the rotating tubular and the outer ring is tethered to the top drive unit. In the event of a disconnect, the tethered assembly holds the load.
Claims
1. A fall arrest system for overhead tools comprising: a main assembly positioned between a rotary unit and a rotating tool, said assembly including a first member and a second member; said first member coupled to said rotary unit; said second member having a first position and a second position whereby said second position couples said second member to said tool; and a bearing assembly positioned between said members whereby said second member rotates with said tool when said second member is in said second position.
2. The system as defined by claim 1 including at least one anchor for coupling said first member to said rotary unit.
3. The system as defined by claim 2 wherein said anchor includes a shock absorber.
4. The system as defined by claim 1 wherein said second member includes a clamping assembly for coupling said second member to said tool.
5. The system as defined by claim 4 wherein said second clamping assembly includes an inner rim, at least one insert and a clamping member whereby said insert traverses said rim and engages said tool when said clamping member is tightened.
6. The system as defined in claim 5 wherein said insert includes a back wedged portion for engaging said rim and a front teeth portion for engaging said tool.
7. A tool fall arrest device comprising: a ring assembly positioned between a rotary unit and a rotating tool, said assembly including an outer ring and an inner ring; said outer ring tethered to said rotary unit; said inner ring having an unengaged position and an engaged position whereby said engaged position clamps said inner ring to said tool; and a bearing positioned between said rings whereby said inner ring rotates with said tool when said inner ring is clamped to said tool.
8. The device as defined by claim 7 including at least one anchor for coupling said outer ring to said rotary unit.
9. The device as defined by claim 8 wherein said anchor includes a shock absorber.
10. The device as defined by claim 7 wherein said second inner ring includes a clamping assembly for clamping said inner ring to said tool.
11. The device as defined by claim 10 wherein said clamping assembly includes an inner rim, at least one insert and a clamping member whereby said insert traverses said rim and engages said tool when said clamping member is tightened.
12. The device as defined in claim 11 wherein said insert includes a back wedged portion for engaging said rim and a front teeth portion for engaging said tool.
13. A method for positioning a safety system for overhead tools, the method consisting of: positioning an assembly between a rotary unit and a rotating tool whereby said assembly includes a bearing between a first member and second member; tethering said first member of said assembly to said rotary unit; and clamping said second member of said assembly to said rotating tool.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] The present disclosure will be more fully understood by reference to the following detailed description of one or more preferred embodiments when read in conjunction with the accompanying drawings, in which like reference characters refer to like parts throughout the views and in which:
[0019] FIG. 1 is a top right perspective view of a tether ring assembly according to the principles of an embodiment of the present disclosure.
[0020] FIG. 2 is a top right perspective view of the tether ring assembly of FIG. 1 with an engaged tubular.
[0021] FIG. 3 is a top plan view of the tether ring assembly of FIG. 2.
[0022] FIG. 4A is a cross-sectional view taken along lines 4-4 of the tether ring assembly of FIG. 3 with the ring assembly in the open position.
[0023] FIG. 4B is a cross-sectional view taken along lines 4-4 of the tether ring assembly of FIG. 3 with the ring assembly in the closed position.
[0024] FIG. 5 is a perspective view of the die/insert of the tether ring assembly of FIG. 1.
[0025] FIG. 6 is a perspective view of the die engagement assembly of the tether ring assembly of FIG. 1 in the retracted position.
[0026] FIG. 7 is a perspective view of a die engagement assembly of the tether ring assembly of FIG. 1 in the activated position.
[0027] FIG. 8 is a frontal view of the tether assembly of FIG. 1.
[0028] FIG. 9 is a cross-sectional view taken along lines 10-10 of the tether ring assembly of FIG. 8.
[0029] FIG. 10 is an exploded view of the tether ring assembly of FIG. 1.
[0030] FIG. 11 is a side view of the tether ring assembly according to the principles of an embodiment of the present disclosure coupled to a tubular and tethered to a top drive unit.
[0031] FIG. 12 is an enlarged view of the circle 12 of the tether ring assembly of FIG. 11.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0032] One or more embodiments of the subject disclosure will now be described with the aid of numerous drawings. Unless otherwise indicated, use of specific terms will be understood to include multiple versions and forms thereof.
[0033] Generally, the bearing ring device of the present disclosure is designed to hold the load of an overhead tool if the rotary unit connection becomes disconnected. While it has been designed to catch a load of approximately three thousand pounds at two feet, it will be appreciated that minor modifications would enable a larger load and a greater falling distance. In any event, the tether is secured to the top drive using a clevis/shackle and a cable sling/chain or any other suitable securement method dependent upon the applicable load. A bearing assembly within the ring allows for the attached assembly to freely rotate as the CRT or drill pipe rotates. Specifically, the ring attaches to the outer diameter (OD) of the tool using an adjustable clamping system. The preferred embodiment can accommodate a tubular OD range of approximately one inch, but it will be appreciated that it can be scaled to any size and range of tool OD. As such, the present disclosure provides for a rotating safety tether ring positioned between the rotary unit on the top drive and a tool, such as a CRT. Essentially, the subject device bites, using a wedge and teeth, onto the OD of a tubular (e.g. CRT) and is then secured (or tethered) to the top drive.
[0034] Turning now to the Figures to better illustrate the device, and in particular FIG. 1, a rotating safety tether assembly ring 10 is shown in a perspective view. This assembly includes a first member comprising an outer ring 12 and a second member comprising an inner ring 14. The outer ring 12 including a grease port 16 to enable the lubrication of the bearings positioned within and between the outer ring 12 and the inner ring 14. These bearings allow the rings to rotate relative one another. More specifically, the inner ring 14 rotates when it is engaged with a rotating tubular via the clamps or dies 18 clamping the tubular OD by tightening the clamping member ring 20 down with the clamp ring bolts 22.
[0035] FIG. 2 illustrates the safety tether ring 10 engaged with a tubular 24, such as a CRT. The safety tether ring 10 includes anchors 26 fastened to the outer ring 12 via bolts 28 or the like. These anchors 26 support the shock absorbers 30 and U-bolts/circle bolts 32 which are tethered to the top drive or other support member. It is the tethers that will catch the disconnected tubular in the event of a disconnect.
[0036] The safety tether ring 10 of FIG. 2 is shown from the top in FIG. 3. This view better illustrates the dies 18 clamped against the OD 34 of the tubular 24. This view also may better illustrate the outer ring 12 and the inner ring 14, and more specifically the relationship therebetween, whereby the inner ring 14 is rotatable relative the outer ring 12 when the clamping bolts 22 tighten the clamping ring 20 down upon the dies and against the OD of the tubular 24.
[0037] The cross-sectional views of FIGS. 4A and 4B will illustrate an open or retracted position whereby the OD of the tubular is not engaged by the dies and a closed or extracted position whereby the OD of the tubular is engaged and locked by the dies, respectively. Referring first in FIG. 4A, the dies/inserts 18 are near the top of the sloped inner rim or ring ramp 36 and the die ring bolts 22 are not completely threaded through the bolt threads 38. When the bolts 22 are tightened against the clamping ring 20, referring now to FIG. 4B, the bolts 22 traverse the threads 38 and the ring pushes the dies 18 down the ramp 36 via the guides (supra) traversing the clamping ring guide channels 40 from the outside of the clamping ring towards the center 42 of the tubular. As such, the dies 18 bite into the OD of the tubular.
[0038] The enlarged view of the die 18 of FIG. 5 illustrates the ramp-wedge backing 44 which rides the inner ring ramp 36, and the insert guide 46 which traverses the channel 40 or die alignment groove of the inner ring from the outside of the ring towards the center 42. The guides or keepers 46 keep the dies moving straight in and out as well as keeping the dies secured at all times. More specifically, the inserts 18 are forced downward using the clamp and wedge design. The back 44 of the die engages the tapered rim 36 of the inner ring and the front have teeth 48 to engage the OD of the tubular. This forces the guide along the groove and towards the center of the tubular and the die teeth 48 bite (penetrate) into the OD of the tubular and clamp/lock the inner ring to the tubular. The load of the tubular then applies more force and the dies bites harder into the tubular. Indeed, if the tool is dropped the wedge design will bite the dies harder to secure the overhead load.
[0039] The die/insert engagement assembly 50 is illustrated in the isolated perspective views of FIGS. 6-7. This assembly 50 includes the clamping or activation ring 20, die ring bolts 22, and the clamping dies or inserts 18. FIG. 6 shows the assembly 50 in an open position whereby the dies 18 are positioned away from the center and FIG. 7 shows the assembly 50 in a closed position whereby the dies 18 are positioned closer to the center. In particular, the die guides 46 of the dies 18 traverse the clamping ring channels 40 from the outside to the inside and the ring is tightened down from FIG. 6 to FIG. 7. Essentially, as activation ring is driven downward, the dies are forced downward, the dies are forced down the inner ring ramp and inward to engage the teeth of the dies on the OD of the tubular.
[0040] The rotational feature of the present disclosure will now be more specifically described. As previously noted, the rotating safety tether assembly ring includes an outer ring, which remains relatively stationary, and an inner ring, which clamps down on the rotating tubular and rotates therewith. This is accomplished via a bearing assembly working between the outer ring and the inner ring. Turning to FIGS. 8 and 9, the rotating safety tether ring 10 is clamped onto a tubular 24. Again, the bearing assembly 52 allows the tubular to freely rotate during normal operation, while maintaining securement. More specifically the activation ring, dies 18 and inner ring 14 will be attached to the tubular 24, while the outer ring 12 stays relatively stationary when the load securement ears or U-bolts 32 are attached to the rig or top drive via an appropriately rated sling, tether or another securement device.
[0041] FIG. 10 is an exploded view of the rotating safety tether ring 10 of FIG. 1. The component parts thereof are illustrated therein. The die engagement assembly 50 includes the clamping ring 20, the dies or inserts 18 and the clamp ring bolts 22. The bearing assembly 52 includes bearings 54 that are positioned within and between the inner ring bearing channel 56 and the cooperating outer ring bearing channel 58.This bearing assembly is lubricated through the grease port 16 and the grease is contained via inner gasket 60, outer gasket 62 and the bearing insert plug 64.
[0042] As shown in FIGS. 11 and 12, shackles and overhead rated safety slings 66 are used to secure the tubular 24 to the top drive 68. In the event that the top drive 68 does not have a suitable securement point, a second tether ring can be installed onto the top drive quill or saver sub above the grabber box assembly. In any event, the rotating tether safety ring 10 assembly allows the tubular 24 to rotate, uninhibited, while it is in operation and still maintain overhead securement. Once secure, the top drive and the tubular can be used as per normal parameters. If, at any time, the tubular backs out of the quill/saver sub (connection to the top drive) it will fall and be caught by the rotating tether safety ring 10 assembly.
[0043] The foregoing detailed description has been given for clearness of understanding only and no unnecessary limitations should be understood therefrom. Accordingly, while one or more particular embodiments of the disclosure have been shown and described, it will be apparent to those skilled in the art that changes and modifications may be made therein without departing from the invention if its broader aspects, and, therefore, the aim in the appended claims is to cover all such changes and modifications as fall within the true spirit and scope of the present disclosure.
