US2347812A - Drivehead - Google Patents

Description

l'l TI DRIVE HEAD Filed March 15, 1 941 W. J. CRITES Ill W May 2j, 1944.

INVENTOR WILBUR J. CRITES w M M Patented May 2, 1944 DRIVEHEAD Wilbur J. Crites, Bartlesville, Okla., assignor to Phillips Petroleum Company, a corporation of Delaware Application March 15, 1941, Serial No. 383,588

Claims.

This invention relates to well equipment, and in one of its more specic aspects pertains to apparatus for use with a well lifting` device.

It has been found that deep well devices of the type disclosed by Steele in U. S. Patent No. 2,202,970, granted June 4, 1940, having a valve or cylinder operated from the. surface of the earth through rotation of a string of tubing, require the tubing string to be accurately aligned and securely supported. Due to the great weight of the tubing string, which must be supported and rotated, plus that of the fluid load when the pump is in operation and the high pressures eX- erted by the gas operating the pump, rigidly secured structure must be employed. This structure must not only be pressure tight but also permit rotation of the tubing, allow ingress of high pressure gas into the well, and the discharge of well uid therefrom. Y

An important object of this invention is to furnish a drive head which will safely permit the entrance of gas under high pressure to operate a deep well lifting means while a string of tubing is being rotated and iiuid from the well is being discharged.

A further object of the invention is to provide a head in which the bearing structure is rigidly secured therein and accurate alignment of the rotatably suspended tubing string is obtained without necessity for frequent adjustments.

Another object is to provide a pump head so made that the well may be read-ily equipped to flow or be torn down for servicing and which permits removal of the inner tubing without simultaneous removal of the outer string of tubing.

Additional objects and vadvantages of this invention reside in its simplicity of design allowing an easily accessible lubricating means for the bearing of the bearing structure, a small num ber of working-parts, and economy of operation.

These and other objects not at this time more particularly enumerated will be apparent during the course ofthe following-description.

In the accompanying drawing, forming a part of this specification and in which like numerals are used to designate like parts throughout, there is illustrated a preferred embodiment of this invention.

Figure 1 is an elevation view, partly in central cross section, of the drivehead of this invention and showing the wall tubing strings.

Figure 2 is an elevationview of the apparatus of this invention operativelyV connected to a well lifting device, such as a known form of gas lift pump generally represented in the drawing.

Referring now more particularly to the drawing, the numeral I represents one or more gas inlets which conduct gas under pressure from a source outside the well to an annular space-2 between the inner tubing string 3 and the outer tubing string li. Inner tubing string 3 is the means for transmission of rotation or oscillation from the driving mechanism on the surface to the gas lift pump depicted in Figure 2. Well tubing 3 is connected to the lower shaft tubing 5 by a threaded coupling E; Shaft tubey 5 is threaded at its upper end and by this means attached to bearing flange plate 1. This bearing flange plate l is attached rigidly to the upper flange part 8 by bolts 9. Inside of this upper flange part 8 is a threaded connection to the lower threaded portion of upper tubing shaft lll. At the upper end of this tubing shaft it is a threaded connection to coupling member i l, and this latter is keyed to the speed reducer l2 which in turn is driven by the motor i3 and belt and pulley system l. These parts just mentioned are the rotating parts of the drive head and serve to operate the gas lift pump Vwhich is suspended in the well on the lower end of tubing string 3;

In operation gas under pressure enters through gas inlet I and passes down the annular spaceZ between tubings 3 and 4 to the pumping mechanism. The fluid from the pumping mechanism flows upwardly in the rotating tubing 3, through lower shaft tubing 5 into the upper tubing shaft It), then through openings lin' whence it is discharged from the drive head through oil outlet l into transfer lines and thence to storage or processing, not shown.

To prevent leakage of the fluid around the upper tubing shaft Il), upper oil packing gland l? and lower oil packing gland t8 are required. These two packing glands are of similar construc-v tion and for convenience, the construction of gland El will be described in detail. This gland is composed of a sleeve member I9, the lower end of which is welded to the upper oil plate 2t', said sleeve member carrying right handed threads on its outer surface. The diameter of this'sleeve member l 9 is suiiiciently larger than the rotating upper tubing shaft lli to accommodate conventional packing, as shown at 2l. The packing is forced into piace by the combined action of the upper follower ring 22 and the upper collar member 23 which is threaded to fit the exterior threads on the sleeve member i9, for packing take up purposes.` Collar member 23 carries slots 24 on the upper shoulder portion spaced at approximately thirty-six degree intervals for the use of a spanner wrench for packing gland tightening or loosening purposes.

Lower oil packing gland I8 is identical in construction and assembly to the upper oil packing gland with one exception, that the correspending lower collar member 25 and lower sleeve member 26 carry left handed threads so that the said lower collar member will not become loosened during normal rotation of the inner tubing assembly. Lower collar member 25 is also equipped with slots at approximately thirty-six degree intervals, similar to upper collar member 23, for tightening or loosening purposes.

Gas packing gland assembly 21 is of the same general construction as the above described oil packing glands. Follower ring member 28 and the collar member 29 in this assembly are similar to those of gland assembly I'I, while the body part or sleeve member 39 is considerably longer and of different shape than sleeve member I9. Sleeve member 30 is screwed into its supporting lower flange 3|. This type of connection between members 30 and 3| permits the diameter of the threaded hole in the upper portion of said lower flange plate 3| to be of considerably larger diameter than that of coupling 6 in order to permit the removal of the inner tubing string 3 therethrough. By inspection of the body part or sleeve member 30 of this gas packing gland, it will be seen that the member is so constructed as to furnish exterior threads for base support, a .bevelled packing ring seat 32 in the lower interior to seat packing 33, and exterior threads on the top portion of sleeve member 30 to accommodate the collar member 29. Numeral 34 indicates a lubricator fitting such as a Zerk fitting for the admission of grease to the relatively large amount of packing in this gland.

Inner tubing 3 being coupled at 6 to shaft tube 5 is rotatably mounted. By referring to the drawing it will be seen that shaft tube 5 is threaded to bearing flange plate 'I which is bolted at 9, to upper flange 8. Upper flange 8 in turn has a threaded connection to tubing shaft I0 at its lower end and as above described, is thereby connected to a'source of power I3, preferably an electric motor. Referring again to bearing flange plate 1, the drawing shows it mounted, upon a ball bearing 35 and an aligning washer 36 seated in a recess 3'I in the top of plate 38. It is this plate 38 which supports the tubing load. The actual load is transmitted from tubing 3 by way of bearing plate I to ball bearing 35, the aligning washer 36, and then to plate 38. Rotation of tubing 3 is imparted from the lower portion of the upper tubing shaft I0, to the upper flange part 8 through bolts 9, and bearing flange plate I to lower tubing shaft 5 and finally to the tubing assembly 3,

Lower flange plate 3|. supports Ythe weight of the drivehead and its load and prevents said drivehead from rotating while the apparatus is in operation. Outer tubing 4 is rigidly attached by a threaded connection into the lower portion of 3| which in turn is held in the usual manner by the well casing head as in conventional practice. 'Ihis lower flange plate 3| is equipped with a grooved ring and threaded bolt holes 39 around its upper circumference for attachment of the lower shell part 40. Said lower shell part 40 has two windows 4| on opposite sides of the shell to permit observation of the `gas packing gland assembly 2'I and to make room for servicing tools. Lower shell part 40 is attached in a similar manner to plate 38 and in turn this plate 38 is attached in like manner by grooved ring and threaded bolts 44 to the upper shell part 42. Upper shell part 42 is provided with four inspection and servicing windows 43 similar to Windows 4I in the lower shell 40. In addition said upper shell is provided with threaded bolt holes for attachment of motor part I3 and speed reducer I2.

In the design and construction of my drivehead, provision has been made for convenience and ease of assembly and servicing of the drivehead as well as for the installation and removal of the gas lift pump and well tubing. For example, the packing gland collar members 23, 25 and 29 are made with IIJ slots each for use of a Spanner wrench.

For removal of the inner rotatable tubing 3, two auxiliary parts or tools may be used for protection of members of the drivehead as well as for mechanical reasons. In the process for removing said inner tubing 3, the fluid outlet I6 and gas inlets I are first disconnected. Bolts 9 are then removed, disconnecting completely the driving mechanism from the driven portion at the interface between upper flange part 8 and the baring flange part 1. Next in the process, the set screws or bolts 44 attaching the upper shell part 42 to the plate part 38 are removed, and the upper shell part and driving mechanism are lifted from their position. A lifting nipple, not shown, is then attached to the exposed threads on the upper end of lower shaft tubing 5, and by this means, after the set screws are removed from threaded holes 39 and collar member 29 and sleeve member 38 of the gas packing gland 2'I removed, the inner tubing portion 3 may be lifted. After the removal of the sleeve member 38 of the gas packing gland from its normal position in the upper part of lower flange part 3|, a bell bushing, not shown, may be inserted therein for the protection of the female threads in the upper part of said lower flange part 3|. Following the placement of this bell bushing, the inner tubing 3 with the gas lift valve mechanism on the lower end thereof, may be removed in a normal manner.

The assembling of the drivehead mechanism with the inner tubing and gas lift pump valve is essentially the reverse of the above described disassembling procedure. Briefly, this assembling comprises lowering the inner tubing 3 with attached gas lift valve mechanism within the outer tubing 4, removal of the bell bushing, not shown, from the upper female threads in lower flange part 3 I, assembling coupling 6, lower shaft tubing 5, and the composite members of gas packing gland 21 and lower shell part 40 with plate part 38 attached. The lower shaft tubing 5, gas packing gland 21, plate part 38, alignment washer 36, ball bearing 35, bearing flange part 'I and lower shell part 40 need not be taken apart during the disassembling of the drivehead and removal of inner tubing 3 from the outer tubing 4, hence its reinstallation is relatively simple. After these aforementioned lower members are in place, the upper shell part assembly 42 is set in position on plate part 38, and the set screws or bolts 44 and bolts 9 are placed. Fluid or oil outlet I6 is connected to lines and storage, not shown, and gas inlets are also connected to the source of gas, not shown. Thedrivehead mechanism is then ready for operation.

Essentially any standard material may be used in the construction of the disclosed drivehead, however, several points should be given consideration in the selection of materials. For example, parts in contact with the oil well fluid should be able to resist the corrosive action of sulfur and sulfur compounds, and brine solutions. Similarly, the gas inlet parts should be constructed of resistant materials in case sour gas or gas containing hydrogen sulfide is used for lifting purposes. f

It is to be understood that the form of this invention, herewith shown and described, is a preferred example of the same and that various modifications may be made therein without materially departing from the spirit of this invention or the scope of the subjoined claims.

Having thus described my invention, I claim:

1. In a drive head for use with a deep well lifting device having stationary outer tubing and rotatable inner tubing spaced therefrom to form an annular passage therewith and in which pressure fluid is admitted into the passage for lifting well fluid through the rotatable inner tubing and in which the rotation of the inner tubing controls the passage of the pressure fluid, the combination comprising a housing, a bearing struc` ture within the housing, a tubular member aligned within the bearing structure and rotatably suspended therefrom, the lower portion of the tubular member being adapted to be connected to and communicate with the upper end of the inner tubing, driving means adapted to be connected to a source of motive power for imparting rotary motion to the tubular member, means for xedly attaching the housing to the upper end of the outer tubing, an inlet passage in the housing for transmitting uid into the annular passage, a fluid outlet passage in the housing communicating with the tubular member, and sealing devices embracing the tubular member at the junctures of the tubular member and the inlet and outlet passages.

2. In a drive head for use with a deep well lifting device having stationary outer tubing and rotatable inner tubing spaced therefrom to form an annular passage therewith and in which pressure uid is admitted into the passage for lifting well fluid through the rotatable inner tubing and in which the rotation of the inner tubing controls the passage of the pressure fluid, the combination comprising a housing including a base portion and a top portion, a bearing structure within the housing and disposed intermediate the base and top portions thereof, a tubular member aligned within the bearing structure and suspended therefrom, the lower end of the tubular member being adapted to be connected to and communicate with the upper end of the inner tubing, driving means adapted to be connected to a source of motive power for imparting rotary motion to the tubular member, means for securing the housing base to the upper end of the outer conduit, an inlet passage in the housing base for transmitting fluid into the annular passage, a fluid outlet passage in the housing cornmunicating with the tubular member, and sealing devices embracing the tubular member at the junctures of the tubular member and the inlet and outlet passages.

3. In apparatus of the character described, the combination comprising a housing including a base portion, a conduit extending downwardly of the base portion, a bearing structure within the housing, a tubular member aligned within the bearing structure and rotatably suspended therefrom, said tubular member extending through the base portion and into the conduit and being spaced from the conduit to form an annular passage therewith, driving means for imparting rotary motion to the tubular member, a well lifting device connected to the tubular member and the conduit and communicating with the tubular member and the annular passage, an inlet passage in the housing for transmitting pressure uid into and through the annular passage to displace well fluid from the lifting device through the tubular member, a scharge passage in the `housing communicating with the tubular member, and sealing means embracing the tubular member at the juncture of the tubular member and the base portion of the housing to prevent the escape of fluid therethrough.

4. In apparatus of the character described, the combination comprising a housing including a base portion, a conduit extending downwardly of the base portion, a bearing structure within the housing, a tubular member aligned within the bearing structure and rotatably suspended therefrom, said tubular member extending through the base portion and into the conduit and being spaced from the conduit to form an annular passage therewith, driving means supported by the housing for imparting rotary motion to the tubular member, a well lifting device connected to the tubular member and the conduit and communicating with the tubular member and the annular passage, an inlet passage in the housing for transmitting pressure fluid into and through the annular passage to displace well fluid from the lifting device through the tubular member, a chamber within the housing communicating with the tubular member for receiving well fluid transmitted therethrough by the lifting device, a discharge passage in the chamber communicating with the exterior of the housing, and sealing means embracing the tubular member at the juncture of the tubular member and the base portion of the housing to prevent the escape of fluid therethrough.

5. In apparatus of the character described, the combination comprising a housing including a base portion, a conduit extending downwardly of the base portion, a bearing structure within the housing, a chamber within the housing, a tubular member aligned within the bearing structure and rotatably suspended therefrom, said tubular member'extending into the chamber and communicating with the interior thereof, said tubular member also extending through the base portion and into the conduit and being spaced from the conduit to form an annular passage therewith, driving means for imparting rotary motion to the tubular member, a well lifting device connected to the tubular member and the conduit and ccmmunicating with the tubular member and the annular passage, an inlet passage in the housing for transmitting pressure fluid into and through the annular passage to displace well fluid from the lifting device through the tubular member, means establishing communication between the interior of the chamber and the exterior of the housing, and sealing means at the junctures of the tubular member and the chamber and the base portion of the housing to prevent the escape of uid therethrough.

WILBUR J. CRITES.

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