US1822412A - Novel packer for use with overshot - Google Patents

Description

Sqpt. 8, 1931. G. MEYER 1,822,412

NOVEL PACKER FOR USE WITH OVERSHOT Filed Oct 1. 1929 2 Sheets-Sheet l UNI 17 TTa/PNEV Sept. 8, 1931.

G. MEYER NOVEL PACKER FOR USE WITH OVERSHOT Filed Oct. 1, 1929 I F i Z- 5/ 4 2 2 i l 0 40 "Z F- 51/ i I so 40 Z I. 57 62 v I d 4 2 Sheets-Sheet 2 /s3 if J i k l /32 "44 V55 4/54 37 4' 42 i Mi //vv/\/T0P GERHAA D MEYER BY F77- TOA A/EM Patented Sept. 8, 1931 PATENT OFFICE GERHARD MEYER, OF LOS ANGELES, CALIFORNIA NOVEL PACKER FOR USE WITH OVERSHOT Application filed October 1, 1929.

My invention relates to packing devices and finds utility in many arts. One art in which it finds particular utility is the oilwell drilling art, and it is in this capacity that I will particularly describe it. I am, however, not limited to this art, for my packing device also finds marked utility in other arts where a packing'device is required to seal a moving and a stationary element, or two elements which are both stationary.

In the oil-well drilling art it is not infrequent for a drill pipe, or other member, to break off at a point some distance below the surface of the ground. When this occurs a suitable overshot is lowered into the well and engages some portion of the broken-off member. Frequently it is impossible to raise this member due to its being sanded in.

It is an object of this invention to pro- 2 vide a novel packer for use with an overshot, this packer being hydraulically operated to engage the broken-off member and allow a flow of fluid to take place around the member, thus freeing it. 4

My packer comprises a packing member carried in a packing-retaining structure with a tapered interior, this structure being rotatable relative to an element which it is desired to seal off. The fluid pressure, and in some cases friction between the tapered interior and the packing member, causes the packing member to tightly engage one of the elements being packed oif, the packing-retaining structure engaging the other element to be packed off.

It is an object of this invention to provide a packing device for packing ofi two elements in which the rotation of one element does not cause a wearing-away of the packing member.

Another object of my invention is to provide a packing member carried in a packingretaining structure which engages one of the elements to be packed off.

Still a further object of this invention is to provide a packer which may be hydraulically operated to clamp it in tight engagement with one of the elements being packed ofl.

Another object of my invention is to provide a packing device in which. the packing Serial No. 396,450.

member will not be injured in passing over i a member havin a ragged, broken edge.

Still other ob ects and advantages will be manifest to one skilled in the art from the following description of my invention.

Referring to the drawings in which two usesof my invention are illustrated,--

F1g. l is a utility view showing my packer 1n con unction with an overshot.

F 1g. 2 is a vertical sectional view of the 00 packer and overshot illustrated in Fig. 1.

F1g.' 3 is a sectional view taken on the line 3-3 of Fig. 2, and illustrating the details of one type of overshot.

Fig. 4 is a perspective view, partially broken away, of the packing member of my in vention.

Fig. 5 is a perspective view, partially broken away, of the packing-retaining structure of my invention. 1 7

Figs. 6 and 7 are vertical cross-sectional views showing my packer in different positions Fig. 8 is a view illustrating my packing device applied to a turbine. 4

It is customary to drill deep wells by means of a rotary bit 10 held in the lower end of a drill pipe 11, this drillpipe being rotated at the surface of the ground by means of a suitable rotary machine, not shown. This drill pipe is formed of sections 12 held together by tool joints 13 or other collars which are slightly larger in outside diameter than the outside of the drill pipe. Due tolarge stresses set up in a long drill pipe, it is not uncommon for the pipe to break, and it then becomes necessary to fish for the .bit 10 and that portion of the drill pipe below the break. This is ordinarily accomplished by lowering a Wash pipe 15 1n the Well, this wash pi e, having an overshot 16 secured thereto. T e lower end of the overshot is beveled so as to readily slip over the upper end of the broken drill pipe. The wash pipe is lowered until the overshot slips over a tool joint 13. At $15 this time, suitable engaging means 18 in the 4 overshot 16 spring inward and engage the lower end of the tool joint. By drawing u ward on the wash pipe 15, the broken drill .pipe may then be raised. The details of one type of overshot 16 are illustrated in Figs. 2 and 3.

Referring to these figures, the overshot 16 illustrated has a body 20 having an opening 21 therethrough of sufficient diameter to easily pass the tool joint 13. Formed in the opemng 2] is an annular channel 23 which is adapted to receive a plurality of dogs 24 whlch, in this type of overshot, comprises the engaging means 18. These (logs are equally spaced around the channel 23 and are pivoted to the body 20 by pins 25.

Springs 26 bear against the dogs to normally hold them in an innermost. position, shown in Fig. 3. The lower surfaces of the dogs 24 are inclined as indicrted at 27 so as to press these dogs into the channel 23 when the upper end of a tool joint 13 comes into engagement therewith. As soon as the wash pipe has been lowered sufliciently to allow the dogs 24 to clear the under side of the tool joint, the springs 26 act upon the dogs to force them into a position shown in Figs. 2 and 3, where they engage the lower surfaces of the tool joints. By drawing upward on the wash pipe 15, it is often possible to raise the broken drill pipe.

Such a procedure is often complicated by the fact that sand may enter the lower portion of the well, thus enclosing the bit 10 and a portion of the drill ipe. When this occurs, it is often impossi le to move this drill pipe after the overshot has engaged the uppermost tool joint 13 of the broken drill pipe.

5 When this occurs, practically the only solution of the problem is to force mud downward through the wash pipe 15 and through the drill pipe 11, this mud then entering the lower end of the well through openings in the bit 10 and rising in the well, thus displacing the sand structure which is holding the broken drill pipe and bit in the well. It is, of course, necessary to use high pressure on this mud, and if this procedure is to be followed it is necessary to pack the wash pipe and the drill pipe in fluid-tight relationship by means of a suitable packer 30.-This packer incororates the novel features of this invention which will now be described.

Referring to Figs. 1 and 2, the packer 30 comprises a retaining member 31 which is externally threaded to engage the upper end of the overshot body 20. The upper end 0 the retaining member is internally threaded to receive a male portion 32 of a coupling member 33, this coupling member having an upper female portion 34 which is threadedly secured to the lower end of the wash pipe 15.

As best shown in Figs. 6 and 7, the retaining member 31 has an annular channel 36 formed therein, this annular channel being defined at its lower end by a shoulder 37 of the retaining member 31 and at its upper end by a lower end 38 of the male portion 32. Rotatably mounted in the annular channel 36 is a packing-retaining sleeve 40 formed of a diameter which is slightly smaller than that of the annular channel 36 and of a length which is shorter than the length of this channel. Secured in the upper end of the packing sleeve 40 is a ring 42 which is also of a slightly smaller diameter than the annular channel 3 so as to be rotatable therein. The sleeve 40 and the ring 42 cooperate to form a packingretaining structure 43 which is rotatable 1n the annular channel 36. i

The packing sleeve 40 is annular in shape and has a frusto-conical opening 44 therein, this opening being larger at the upper end of the packing sleeve than at the lower end. The opening 44 terminates at its lower end in a V groove 46, best shown in Figs. 5 and 7, the upper end of the opening being partially closed by the ring 42.

Adapted to longitudinally move in the frusto-conical opening 44 is a packing member 50, this member having upper and lower ring surfaces which are shaped to conform to the frusto-conical opening 44 when the packing sleeve is in an uppermost position, indicated in Fig. 7. At this time, an inner surface 51 of the packing member is adapted to engage the outer periphery of an element which it is desired to seal OK. In this instance the element is in the form of a tool joint 13, this tool joint being the one engaged by the overshot 16. The upper and lower ends of the surface 51 are diverging, as indicated by the numerals 53 and 54 respectively. The diverging surface 54 forms a V portion 55 on the'lower end of the packing member 50, this V portion being adapted to engage the V groove 46 when the packing member 50 is in its lowermost position indicated in Fig. 6. Similarly, the upper end of the packing member forms a V portion corresponding in taper to the lower edge of the ring 42.

This packing member 50 moves from its position indicated in Fig. 7 into its position indicated in Fig. 6, when the Wash pipe 15 is drawn upward a distance so that the engaging means 18 engages the lower surfaces of the tool joint. When moving downward in the opening 44, the packing member 50 is tightly compressed between the tool joint and the f packing sleeve 40, thus forming a tight joint therebetween.

During this movement the packing member maintains a large surface of contact with the tool joint due to a channel which allows for a compression of the packing member, this channel decreasing in size as the packing member lowers in the packing sleeve. It should be clear that when an upward stress is placed on the wash pipe 15, the packing member 50 will engage the V groove 46 and will force the packing sleeve downward in engagement with the shoulder 37.

usually in the form of a mud and is under high pressure. Due to the fact that the packing-retaining structure 43 fits loosely in the annular channel, this pressure is transmitted to the annular channel 60, formed around the packing member 50, through openings 61 formed in the sleeve 40 and acts to increase the sealing pressure on the packing member in a manner to hold it still more tightly into engagement with the tool oint. Due to the fact that the fluid pressure above the packing device is invariably higher than that below this device, another hydraulic force is set up forcing the packing member downward in the sleeve 40. Thus, the fluid pressure acts on the packing member both longitudinallyand radially in a manner to increase the sealing engagement between this packing member and the tool joint.

The longitudinal or downward force exerted on the packing member by the fluid pressure forces a lowersurface 62 of the sleeve 10 into surface contact with the shoulder 37. I prefer to accurately machine and grind the surface 62 and shoulder 37 so that a very effective metal-to-metal seal is formed.

It is sometimes necessary to rotate the wash pipe 15 after the overshot is engaging a tool oint. Such a condition occurs when it is necessary to release the dogs 24 from engagement with the tool joints in order that the wash pipe may be raised without raising the broken drill pipe. The type of overshot shown in the drawings permits this to be done, there being teeth 63 formed on the upper surface of each dog, these teeth being so formed as to draw the dogs 24 into the channel 23 when the wash pipe is rotated, thus permitting the overshot to be raised relative to the tool joint 13. When this rotation of the wash pipe is necessary, it is highly desirable that the engefiing surfaces of the pack ing member 50 and the tool joint 13 be not moved relative to each other. so that the pack ing member will not become torn. This result is accomplished in my invention by having the packing sleeve 40 rotatable in the annular channel 36. The seal is not broken when the wash pipe is thus rotated due to the engagement between the surface 62 and the shoulder 37. The relative movement between the wash pipe and drill pipe is thus taken care of by the shoulder 37 and the surface 62 rather than between the packing member 50 and the tool joint as would be the case if the packing-retaining structure were not rotatable.

. .The breaking of the drill pipe 11 usually leaves a very ragged edge and I have found that if this edge comes into contact with the packing member 50, it often cuts this member, thus preventing the maintaining of a tight seal. To prevent this contact between the ragged edge of the break and the packing member, I provide a protecting member 65 of such a diameter as to be slidable in the wash pipe 15 and the opening 21, as best indicated in Figs. 1, 2, and 6. The external surface of this member is frusto-conical in shape having an opening 66 therein which is of the same shape. The upper end of this member 65 is only partially closed by a ledge 67 and the lower end of the opening 66 is flared to make the lower edge of the member 65 relatively sharp so as to guide the broken end of the drill pipe 11 into the opening 66. This lower edge of the member 65 normally rests on the dogs 24 of the overshot 16 during the lowering of the overshot, these dogs forming a very satisfactory supporting member therefor. the break the drill rod enters the openings 66 until it seats therein, as indicated in Figs. 2 and 6.

As the overshot moves downward this protecting member is retained on the upper broken end of the drill pipe and the packing member 50 comes in contact with the protecting member 65 rather than the'ragged break of the drill pipe 11, thus protecting it from damage. It should, of course, be understood that if the overshot were not utilized the protecting member could rest on any suitable supporting member placed below the packing member 50.

While I have thus far particularly described my packing device as being applicable to the oil-well drilling art, this use is notso I As the overshot is lowered over essential to the utility of my invention. For 4 example, in Fig. 8 I have illustrated my packing device as sealing a joint between a stationary element and a rotatable element 91, where the pressure inside the stationary element is greater than that outside this element. This condition is met in many arts, the steam turbine art being chosen for the purpose of illustration, and the application of my packing device thereto being diagrammatically illustrated in Fig. 8. The stationary element 90 is a portion of the turbine shell and corresponds to the retaining member 31 of the previously described embodiment, a shoulder 92 corresponding to the shoulder 37. Similarly, the rotatable element 91, usually in the form of a turbine shaft, corresponds'to the tool joints with its attached drill pipe sections.

The packing-retaining structure 43 and the packing member are identical with those ing structure rightward so that the shoulder 37 comes into surface contact with the shoulder 92, thus forming an effective seal between these members. This fluid pressure also acts radially inward on the packing member to compress this member against the rotating element, and also acts longitudinally on the left end of the packing member to move this member rightward, which in turn acts to compress this member against the rotating element 91 due to the taper on the inside of the sleeve 40.

It should thus be clear that the packingretaining structure 43 rotates with the element 91 and that there is no wear between the packing member and the element 91 due to this rotation. Furthermore, this packing device permits small movements of the rotating element 91 relative to the stationary element.

Any amount of leftward movement of the rotating element 91 is compensated for by a relative movement of the packing member and the element 91, this leftward movement tending to release the grip 'of the packing member on this element. The internal pressure of course tends to keep the shoulder 92 and shoulder 37 in sealing contact, but if the shoulder 37 were to be momentarily moved away from the shoulder 92, the flow of steam or other fluid outward therebetween would lower the pressure in this space and increase the tendency for the shoulder 37 to move into contact with the shoulder 92 under the influence of the fluid pressure inside the element 90. Slight rightward movements of the element 91 relative to the element 90 may be taken care of due to the resiliency of the packing member 50, this member being ordinarily made ofrubber or a compound thereof. Further rightward movement causes a slipping between the packin member and the rotatable element, but I ave found this slippage may take place without injury to the packing member, especially where the fluid inside the stationary element acts as a lubricant for the packing member.

My invention thus comprises the use of an auxiliary structure which is in sealing engagement with one of the elements to be sealed off, and which is sealed relative to the other element by means of a packing member which is stationary relative to this other element.

I claim as my invention:

1. In a packing device for sealing primar and secondary elements, the combination 0 a packing-retaining structure rotatably engaging one of said elements; and a packing member retained in said packing-retaining structure and compressed against the other of said elements.

2. In a packing device and secondary elements, the combination of: a fluid-operated packing-retaining structure rotatably engaging one of said elements; and

for sealing primary a packing member retained in said packingretaining structure and being fluid operated in a manner to hold same compressed against the other of said elements.

3. In a packing device for sealing primary and secondary elements which may be rotatable relative to each other, the combination of: a packing member around said primary element; and a packing-retaining structure holding said packing member compressed against said primary element, said structure engaging said secondary element in sealing relationship therewith.

4. A combination as defined in claim 3 in which said packing-retaining structure. is held in sealing relationship with said secondary element by fluid pressure in said secondary element.

5. A combination as defined in claim 3 in which packing-retaining structure is held in sealing relationship with said secondary element by fluid pressure in said secondary element, and in which said packing member is compressed around said primary element by said fluid pressure.

6. In a packing device for sealing primary and secondary elements which may be rotatable relative to each other, the combination of: a packing member around said primary element; and a packing-retaining structure holding said packing member compressed against said primary element, said structure rotatably engaging said secondary element in sealing relationship therewith.

7. In a packing device for sealing primary and secondary elements which may be rotatable relative to each other, the combination of: a packing member around said primary element; and asleeve having a tapered interior in which said packing member may be moved to engage said primary element, said sleeve having a surface in sealing engagement with a shoulder of said secondary element.

8. In a packing device for sealing primary and secondary elements which may be rotatable relative to each other, the combination of: a packing member around said primary element; and a sleeve having a tapered interior in which said packing member may be moved by -fiuid pressure in said secondary element to engage said primary element, said sleeve having a surface in sealing engagement with a shoulder of said secondary ele ment.

9. In a packer, the combination of a packing sleeve having a frusto-conical opening therethrough; a retaining member holding said packing sleeve; and a flexible packing member in said sleeve, said packing mem her being longitudinally movable in said opening to engage an element which it is desired to seal off.

10. In a packer, the combination of: a packing sleeve having a frusto-conical opening therethrough; a retaining member holding said packing sleeve; :1. flexible packing member in said sleeve, said packing member being longitudinally movable in said opening to engage an element which it is desired to seal off; and means for introducing hydraulic pressure adjacent said packing member to increase the force of engagement between said packing member and said element.

11. A combination as defined in claim 9 in which said packing member has an annular channel therea'round, and including mians for supplying a liquid to said channe 12. A combination as defined in claim 9 in which said packing sleeve and said packing member have complementary V-shaped surfaces at the smaller end of said frustoconical opening.

13. In a packer, the combination of: a coupling member; a retaining member threadedly received by said coupling member, said retainin member having a channel therein; a pac ing sleeve rotatabl held in said channel, said sleeve having a rustoconical opening therethrough; and a packing member longitudinally slidable in said opening to engage an element which it is desired to seal ofl'.

14. In a packer, the combination of: a.

coupling member; a retaining member threadedly received by said coupling member, said retaining member having a channel therein; a packing sleeve rotatably held in said channel, said sleeve having a frustoconical opening therethrough; a packing member longitudinallyslidable in sa1d opening to engage an element which it is desired to seal ofi, said packing member having a channel therearound; and means for forcing a liquid into said channel to increase the force of engagement between said packing member and said element.

15. In a packing device for sealing primary and secondary elements, the combination of: a fluid-operated packing-retaining structure rotatably engaging one of said elements; and a packing member retained in said packing-retaining structure and adapted for fluid operation to hold the same compressed against the other of said elements.

16. In a packing device for sealing primary and secondary elements, the combination of: a fluid-operated packing-retaining structure rotatably engaging one of said elements; and a fluid-operable packing member retained in said packing-retaining structure and being fluid-operated to compress and hold the same against the other of said elements.

In testimony whereof, I have hereunto set my hand at Los Angeles, California, this 27th day of September, I929.

GERHARD MEYER.

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