US2211881A - Kelly bar bushing - Google Patents

Description

20, 1940. c. H. COLLETT ET AL 2,211,881

KELLY BAR BUSHING Filed April 5, 1939 2 Sheets-Sheet l Hm my f a N M MN MW [m 4 WM g- 1940- c H. COLLETT ET AL 11,881

KELLY BAR BUSHING Filed April 5, 1939 2 Sheets-Sheet 2 Armk/vfy Patented Aug. 20, 1940 KELLY BAR. BUsH NG Collett, Walnut Park, and Millman M.

Ayres, Los Angeles, Calif.

Application April 5, 1939, Serial No. 266,126

Charles H.

7 Claims.

This invention relates to oil well tools and particularly pertains to a Kelly bar bushing for rotary well drilling equipment.

In the drilling of oil wells by the rotary method The invention is illustrated by way of example in the accompanying drawings, in which:

I Figure 1' is a view in side elevation showing the assembled Kelly bar structure as mounted within a rotary table.

Fig. 2 is an enlarged view in central vertical section through one wall of. the bushing as seen on the line 2-2 of Fig. 1. f Fig. 3 is an enlarged view in vertical section side walls, thus making it possible to raise and lower theplates for purposes of adjustment. 4

The anti-friction bearingstructures '20 are in the form of endless chains- These chains com & it is common practice to use a string of drill pipe through one of the endless anti-friction bearing at the lower end of which a drill bit is positioned, members as seen on the line 33 of Fig. 2. and at the .upper end of which a Kelly bar is at- Fig. 4 is a View in-plan showing the structure tached. The Kelly. baris usually square in secin elevation. v tion and passes throu'gha Kelly bar bushing in Fig. 5 is a view in transverse section through the rotary tab1e,jwher eby it may be free to slide the side wall showing the endless bearing struc- 10 vertically during drilling operation while being ture as being housed. I Y positively driven and rotated by the table. Under Fig. 6 is a perspective view of one of the roller such conditions it isobvious that there is a tendmembers 28. ency for a great amount. of friction to beset up Fig. '7 is a perspective view ofone of the disc between the Kelly bar and the bushing .through members 29. v 1 15 which it extends whendriving power is applied Referring more particularly to the drawings, and when the Kelly bar is movedup and down l0 indicates the body of the Kelly bar bushing through the ,bushing. Various expedients have with which the present invention is concerned. .been provided for eliminating this friction. In This bQdy'iS- Substantially Square in horizontal 29 most instances, however, the wear has been imarrangement, having vertical side walls |:l 'l2, 2o posed at..points of relatively small ,area which l3 and M. Disposed below the square portion has caused thepartsto berapidly worn out and of the body is an enlarged squared shoulder I5 v.to require repair. j. V below which a'tapere'd portion l6 isformed. .The It is the principal objector" the presentinventapered portion l6 fits. within the usual seat l] F tion to provide a Kelly bar bushing in which a .formed within' a bushing or directly within ,a 25 relatively large surface area is exposed to the rotary table l8. jFormed' through the side walls Kelly bar and, .alsov a relatively large surface II to M and above the shoulder I5 are openings area is provided upen the bushing, while a minil9. These openings are substantially rectangular mum amount of friction occurs between the varin shapeand serve as passageways through which {39 ions movingparts .of the structure, thus insuring endless friction bearing members 20 may move.- 30 that the ,Kellybar may move freely through the Mounted uponlthe inner faces of each of the bushing without binding or excessive friction, and fwallsfl l .t0 l4, inclusive, are wear plates 2|. that at the same time the moving parts of the These plates, as shown in vertical section in Kelly bar are not liable to be worn and require .Fig. 2 of the drawings, are indicated as having repair. Another object of thepresent invention an upper overhanging flange 22 .and a downward- 35 is to provide an endless anti-friction bearing 1y extending plate portionformed with a central chain, particularly adapted for use in connection ,groov'e23 therein. The central groove 23 extends with the present invention but also having feavertically and serves as a guide for the endless tures rendering it of considerable advantage in anti-friction bearing member 20. The lower end various other mechanicalstructures. of each of the guide plates 2| has a curved sur- 40 The present invention contemplates the proface. 24 leading into'the lower end of the groove vision of a Kelly bar bushing having a main while the upper end of the bearing plates have a housing adapted to properly seat within the 'rocurved surface 25, thus making it possible for tary table of a drill rig, and through which a the endless anti-frictionbearing member to travel Kelly bar may reciprocate, the bushing carrying freely. around the upper and lower edges of the endless anti-friction bearing elements interposed 'plates 2i and around theouter sides of the porbetween the Kelly bar and the body of the bushtions of the vertical walls embraced by the antiing whereby free movement of the Kelly bar may friction members. The plates are held in posibe attached with a minimum amount of friction tion by counter-sunk cap screws 26. These cap and wear. screws extend through slotted openings 21 in'the 50 prise roller members ZB and disc members '29 The roller members 28 are formed with a pair of spaced rollers and 3| connected by an inter-- mediate pin portion 32. The pin is of relatively small diameter and spaces the rollers a distance apart to receive the discs 29. The roller portions 30 and 3| and the discs are of the same diameter and may be of any desired width although they are here shown as being the same Width. This provides an adequate transverse bearing surface as well as a continuous one. The roller structures 28 are preferably made with the pins 32 and. the roller elements 30 and 3| integral. However, at the end of the roller chain it is desirable to provide a roller structure in which the roller portions 30 and iii are separable. Such a structure is indicated in Fig. 3 of the drawings, where it will be seen that the pin 32 has a threaded extension 33 which fits within the threaded bore of the roller 30. The roller structures and the discs are not pinned together but are connected by novel anti-friction means comprising bearing balls 34 which run in complementary semi-circular ball races 35 and .36 formed in the contiguous faces of the roller sections 39 and 3| and the discs 29. The bearing balls are placed within the races by the removal of a threaded plug 3! which is normally positioned within a transverse bore 38 of a diameter slightly greater than the diameter of the bearing balls. Thus, the balls may be placed within this bore and then moved until they assume the interlocking positions shown in Fig. 3 of the drawings, after which the plug 3? is placed in position and will close the ball races so that the balls will stay in place and will hold the roller structures 28 and the discs 29 in interlocked engagement While permitting relative rotation between the roller structures and the discs.

The length of the endless anti-friction bearing structure 20 is sufficient to properly encircle the portion of the side walls between the openings l9 and the upper edge thereof and the embraced portion of the wear plates 2|.

Due to some cause, the anti-friction bearing structure 28 might break, in which case the parts might pass downwardly through the rotary table and into the well. This would be objectionable and in order to overcome this a ledge 39 is formed around the central opening 40 in the body of the Kelly bar bushing and upon this ledge a bushing structure 4| is mounted. This structure has an overhanging lip 42 which rests upon the ledge 39 and a downwardly extending portion 43 which projects downwardly and along the side faces of a Kelly bar 44. The bushing members 41 do not fit tightly against the side faces of the Kelly bar but are spaced relatively close thereto to prevent parts from passing down into the well, a

In Fig. 2 of the drawings the endless bearing element 20 is shown as being exposed. It will be understood, however, that a construction might be used in which the bearing structure is closed, such for example as shown in Fig. 5, where it will be seen that a channel 45 is formed in the back of the side wall of the bushing body, and that this is covered with a plate 46, thus concealing the length of the bearing structure which passes along the outside of the bushing.

In operation of the present invention the slip structure is assembled as shown in the drawings, after which the device may be mounted suitably in a rotary table. A Kelly bar is then passed through the structure. It will be understood that the device has been so designed as to cause the surfaces of the rollers 28 and the discs 29 to contact the surface of the Kelly bar while bearing against the face of the wear plate 2!. As the Kelly bar moves up and down within the bushing the endless anti-friction bearing structure 20 is free to adapt itself to this movement as the rollers and discs roll back and forth. It will be evident that in the event the Kelley bar moves any appreciable distance the endless bearing member 2!] may pursue its path of travel one or more times. It will also be evident that as the Kelly bar moves vertically the anti-friction hearing structure 20 will move, and the rollers 28 and the discs 29 will assume different positions between the faces of the grooves 23 in the wear plates and the faces of the Kelly bar. This will prevent undue wear at any one point and will insure a long life to the anti-friction bearing member, while making it possible for the Kelly bar to be moved easily during driving operations of the rotary table.

It will be recognized that although the endless anti-friction members have been shown as used with a Kelly bar bushing that the construction of these elements and their manner of articulate connection makes them desirable for various other uses and gives them novelty exclusive of their use in the present setting. It is to be understood also that while the Kelly bar bushing is here shown as being used with a chain-like antifriction structure that the invention is not limited to this construction but includes any type of moving bearing element which has relative bodily movement with relation to the bushing as well as the Kelly bar.

It will thus be seen that the structure here disclosed, while simple in operation and arrangement, provides an effective bearing structure for reciprocating members such as the Kelly bar of a drill rig whereby rotation may be imparted readily to the Kelly bar while permitting it to have free longitudinal movement.

While we have shown the preferred form of our invention as now known to us, it will be understood that various changes may be made in combination, construction and arrangement of parts by those skilled in the art, without departing from the spirit of our invention as claimed.

Having thus described our invention, what we claim and desire to secure by Letters Patent is:

1. In combination with a rotary table and a Kelly bar adapted to be driven thereby, a Kelly bar bushing mounted on the rotary table and through which the Kelly bar extends, guide leans on the Kelly bar bushing and extending longitudinally thereof. and endless antifriction members carried by the Kelly bar bushing and interposed between said bushing and the Kelly bar, comprising a plurality of rollers having annular grooves in their opposite faces, intermediate rollers of the same diameter having annular grooves in their opposite faces and being disposed in overlapping relation with the grooves of the contiguous faces of the first mentioned rollers, and ball members positioned within the overlapping grooves of the pairs of rollers for articulately interlocking the rollers together.

An endless anti-friction member comprising pairs of rollers, other rollers intermediate said pairs of rollers, and means articulately connecting the pairs of rollers and the other rollers, said articulate means comprising ball members positioned within overlapping grooves formed on the contiguous faces of the first and second mentioned rollers.

3. An endless anti-friction structure comprising pairs of rollers laterally spaced from each other, intermediate rollers disposed with their edges between the edges of said pairs of laterally spaced rollers, and articulate means between the overlapping edges of said pairs of rollers and intermediate rollers whereby all of said rollers are free to rotate on their independent axes.

4. An endless anti-friction bearing structure comprising pairs of rollers rigidly spaced from each other, said rollers having an annular groove in their opposing faces, intermediate rollers of the same diameter as the first mentioned rollers and having annular grooves in their opposite faces and being disposed in overlapping relation with the grooves of the contiguous faces of the pair of rollers, and ball members positioned within the overlapping grooves of the pairs of rollers and the intermediate rollers for articulately interlocking the rollers together.

5. In combination with a rotary table and a Kelly bar adapted to be driven thereby, a Kelly bar bushing mounted on the rotary table and through which the Kelly bar extends, guide means on the Kelly bar bushing and extending longitudinally thereof, an endless anti-friction.

structure carried by the Kelly bar bushing and interposed between said bushing and the Kelly bar, said anti-friction structure comprising a pair of rollers laterally spaced from each other, intermediate rollers disposed with their edges between the edges of said laterally spaced rollers, and articulate means between the overlapping edges of said pair of rollers and intermediate rollers whereby all of said rollers are free to rotate on their independent axes.

6. In combination with a rotary table and a Kelly bar extending therethrough to berotated thereby, a Kelly bar bushing carried by the rotary table and through which the Kellybar' extends, an anti-friction means disposed between the Kelly bar'bushing and the rotary table comprising a pair of rollers laterally spaced from each other, other rollers intermediate said pairs of rollers, annular grooves formed in the contiguous faces of both mentioned rollers, and ball members positioned within the overlapping grooves of both mentioned rollers for articulately interlocking the rollers together.

7. In combination with a rotary table and a Kelly bar adapted to be driven thereby, a Kelly bar bushing mounted on the rotary table and through which the Kelly bar extends, guide means on the Kelly bar bushing extending longi-i t'udinally thereof, and an anti-friction means carried by the Kelly bar bushing and interposed between said bushing and the Kelly bar, said anti-friction means being free to move longitudinally of the Kelly bar while providing a bearing support between the Kelly bar bushing and the Kelly bar, said anti-friction means comprising pairs of rollers rigidly spaced from each other, said rollers having an annular groove in

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