US2491751A - Vertical deep well pump - Google Patents

Description

Um. 2 11), M49 E. n. McGEE VERTICAL DEEP WELL PUMP 5 Sheets-Sheet 1 Filed Nov. 25, 1947 \NVENTOR.

HIS ATTORN EYS.

mm, 2%, W499 E. l. M GEE VERTICAL DEEP WELL PUMPv 5 Sheets-Sheet 2 Filed Nov. 25, 1947 INVENTOR. Edgar?" 11 N66@ X) I" (IV/J I Hi5 ATTORN EY S.,

mm, m, ww E. B. MOGEE m mm VERTICAL DEEP WELL PUMP Filed Nov. 25, 1947 5 Sheets-Sheet 3 HIS ATTORN EYs.

2Q, 1949 E. 1. McGEE 2,491,75l

VERTICAL DEEP WELL PUMP Filed Nov. 25, 1947 5 Sheets-Sheet 5 INVENTOR.

fogczr L MCWK HIS ATTORNEYS.

Patented Dec. 20, 1949 VERTICAL DEEP WELL PUMP Edgar I. McGee, Uniontown, Pa., assignor to H. C.

Frick Coke Company, a corporation of Pennsylvania Application November 25, 1947, Serial No. 787,928

3 Claims. (or. 103-402) This invention relates to improvements in vertical deep well pumps and more particularly to means for tensioning the shaft tubes thereof.

It is an object of the present invention to compensate for temperature differentials between-the shaft tube and outer column of deep well pumps.

It is a further object to provide a tensioning device for the shaft tube of deep well pumps.

It is another object of the present invention to provide an automatic tensioning device for the shaft tube of deep well pumps which though simple in design is rugged and durable in operation.

The foregoing and further objects will be apparent from the following description when read in conjunction with the attached drawings, wherein:

Figure 1 is a vertical section showing the general arrangement of a vertical deep well pump;

Figure 2 is an enlarged section showing the connection of the shaft tube to the pump;

Figure 3 is a plan of my improved tensioning device;

Figure 4 is a section on line IV-IV of Figure 3;

Figure 5 is a plan of a modification; and

Figure 6 is a section on line VI-VI of Figure 5.

In Figure l of the drawings, there is illustrated a type of vertical deep well turbine or centrifugal pump having as a driving medium between the source of power 2 at the top and a rotary pump t at the bottom, a series of shafts Ii coupled togather to transmit rotary power at high speeds and at high torque. The shafts 6 must resi t a high longitudinal tension created by the weight of the shaft and the pump impellers 8 carried thereby and also by the hydraulic thrust of the impellers or other pumping mechanism. The shafts b are conventionally driven by the motor 2 and carried by a thrust bearing H), which are disposed on a housing l2, resting on supports Hi. In order to prevent violent vibration of the shaft due to the combination of high rotative speed, torsion and tension, a plurality of bearings it are provided. These bearings are disposed within a. nonrotating shaft tube It), which encloses and protects the shaft and bearings from corrosive liquids being pumped and provides oil or other lubricant for the bearings. It is usually made up of extra heavy pipe of as small a size as is practical and in convenient lengths for the required spacing of the bearings and is coupled in such manner that will be liquid tight and withstand high longitudinal tension to support its own weight from the top together with an additional tension 2 at the bottom to dampen vibration set up by the rotating shaft.

A plurality of shaft tube stabilizers 20 that allow free vertical movement but prevent horizontal movement of the tube are used to prevent weaving action of the tube. These are supported by spiders 22 in a large tubular column 24 and may be spaced at 50 to ft. intervals but in addition to these hearings, the tube also requires tensioning to avoid building up to a damaging vibration.

The large tubular column 26 is welded or otherwise suitably secured to the supports Id and carries pump bowl 26 attached to its lower end. The column 2t conducts liquid bein pumped to its top outlet 28 comprising an L coupling 30 mount ed on the upper side of support it and disposed in the housing It. This column is in tension, and in deep settings (often 500 or 600 ft.) this tension becomes very great due to weight of the column and the weight of the pump plus the weight of the column of liquid being pumped. Thus, this column, even in the larger pipe sizes, becomes responsive to the vibration set up by the rotating shaft.

Because of the numerous bearings in the shaft tube it, it operates at a higher temperature than the outer column 24, especially if the outer colworm is insulated by a rubber covering 25 for protection against acidulous liquids being pumped. The shaft tube may likewise be rubber covered which increases the temperature differential. In the preferred embodiment, however, the shaft tube It is formed of stainless steel which does not need protection from acid liquids.

Moreover, these pumps are often hung in the intake air shaft of mines through which passes, at high velocity, warm air in warm seasons and cold air in cold seasons while the mine water remains at practically the same temperature throughout the year. Thus in hot weather the inner tube can temporarily be at a lower temperature than the column when the pump has stopped pumping the cool mine water and the air warms the column before the tube warms up. With these changing conditions, it is obvious there is a constantly varying difierence in the temperatures of the tube and the column.

With these changing relative temperatures, there occurs a corresponding change in the relative lengths of the shaft tube and column. This difference will be A" in a 500 ft. setting with 20 F. difference in temperatures.

Since these two parts are both rigidly connected at the bottom by vanes 32, as is shown in Figure 2 of the drawings. any rise in the tube temperature above the column temperature relieves the original tube tension and allows it to stand in compression from its weight on this fastening at the bottom. This tends to magnify any vibration or weaving of the tube and also increases the tension on the column and allows the vibrations to become harmful. If this tube slack is taken up by non-flexible screw or tnread arrangement while the tube is at a higher temperature than the column, the tube is then subjected to a damaging strain when the temperatures again become equal or reversed. While it is true that the tube stretches slightly and the column can shorten slightly, an excessive tension is created in the tube because the column is more rugged than the tube and the tube is often overstressed and damaged because of unforeseen temperature changes.

To avoid this damage and/or the necessity of frequently readjusting the tube tensioning device, I have provided the hereinafter described means for automatically compensating for the changing relative lengths of the two members. As is shown more clearly in Figures 3 and 4 of the drawings, the tensioning device 34 is disposed in the housing l2 and is mounted on the L coupling 38 through which the drive shaft and shaft tube extend. A stuffing box 36 is disposed around the shaft tube at the upper end of the L member 30 in order to seal off the upper end of the L member. This stuffing box is controlled by gland 31 and stud bolts 31. A stuffing box 38 is likewise carried by the upper end of the shaft tube to seal the opening between the drive shaft 6 and the shaft tube I8. Pressure thereon is regulated by stud bolts 39 and gland 39'.

Mounted around the stuifing box 36 on an annular stud member 40 integrally formed on the L member 30 is a horizontally disposed ring member 42 having a depending annular flange 44 which fits inside of the annular stud member 40. A plurality of elongated vertically disposed studs 46 are welded or otherwise suitably secured to the ring 42 and coil springs 48 are slipped thereover. These springs form a cluster of sufficient strength to support the weight of the shaft tube and at the same time provide the desired tension at the bottom of the tube shaft. These springs must also have sufiicient range of action to avoid too much variation in tension with changes in the shaft tube length. The springs are compressed and support the tube shaft by means of bolts which extend between a compression ring member 52 slipped over the studs 46 above the springs and a flanged sleeve 54 which is screw-threadedly mounted on the end of the shaft tube and locked thereon by means of a lock nut 56. The bolts 56 are directly inside the studs 46 so as to compress the springs 48 without binding. The upper end of the shaft tube is exteriorly threaded over considerable distance to provide ample adjustment of the position of the flanged sleeve 54 to compensate for manufacturing tolerances in the shaft tube elements, etc.

The tube is tensioned by uniformly tightening the nuts on the compression bolts 50. This applies the load to the springs which are proportioned to provide the required and predetermined load necessary to properly support. and tension the tube. Because spring loads are not constant but vary in direct ratio to the amount they are compressed, the tube tension will vary as the relative lengths of the tube and column vary. The proper amount of tension can be established by knowledge of the characteristics of the springs and the springs compressed a predetermined amount when both tube and column are at the same temperature, i. e., at the time of their being installed in suspension in the mine shaft or well. This adjustment, when properly established, will allow ample extension of the springs to compensate for a relative lengthening of the tube without relieving too much of the required tension in the tube as it warms up in operation. The same adjustment will also allow a further compression of the springs to compensate for a relative shortening of the tube without overloading the springs or overstressing the tube when the tube temperature might become lower than the column temperature as previously described.

The foregoing design is preferred for new pumps where ample headroom can be provided. However, since such headroom is limited in existing pumps, I have also provided the modification shown in Figures 5 and 6 for application to pumps already built. This design is more compact and for this reason may cost slightly more to build.

In the modified arrangement, the lower stuffing box 36' is disposed below the top of the L member 30 and is compressed between a split gland 60 and lower gland 6|. The lower gland 6| is secured to an internal annular flange 64 by a plurality of lower stuffing box studs 63. The split gland 60 has a ring 62 mounted on its outer shoulder 65 and is drawn down by two gland studs 61 also screwed into the flange 64. Springs 48 are mounted around studs 46' welded or otherwise secured to ring 42' disposed on the flange 40'. The upper ends of the studs 46' are internally screw-threaded as at 66. An annular cap member 68 having the upper inside corner cut away to form a shoulder 10 is adapted to fit over the upper ends of the springs 48'. Studs 12 threaded at both ends are adapted to be positioned through the cap member 68 and screwed into the threads 66 of the studs 46. The shaft tube I8 is interiorly threaded at the upper end thereof as at 14 and a flaring gland nut 16 is adapted to be screwed therein. The gland nut 16 is exteriorly threaded as at 18 and carries a stuffing box on its interior mid-portion. Pressure on this stuffing box is controlled by stud bolts 8| and gland 8|. An interiorly screwthreaded ring nut 82 is adapted to screw-threadedly engage the threads 18 and has an annular flange 84 which is adapted to engage the shoulder t 10 on the cap 68. Struts 86 which are quarter segments of a length of tubing are adapted to be disposed on ring 62 while ring 62 temporarily rests on flange 64 before the split gland 66 is disposed between the packing and ring 62. The struts 86 engage the gland ring 16 at shoulder 88 to limit the downward movement thereof and the attached shaft tube while releasing the pressure and gaining slack between rings 68 and 82 in order to screw ring 82 further down on threads 18. The length of the struts 86 is approximately 1 to 2 longer than the distance Y between the ring 62 while resting on flange 64, and shoulder 88 before any stretching of the shaft tube. In the particular design shown, the coil springs 48' comprise 13 coils of a pitch so that the unloaded length thereof is 9%". The gland nut 16 may be locked in position by a split ring 99 having arms 92 which engage a pair of oppositely disposed spring coils 48'.

To apply tension to the shaft tube, the shaft tube and outer column are assembled and tight- 7 ened while at the same temperature. The tubeto gland nut i6 is then screwed down tightly on a hard intermediate gasket on the shaft tube it. The struts are then cut to length as before described. The nuts on stud bolts l2 are then turned down until the coils of springs 48 are pulled into solid contact. Ring nut 82 is then screwed down so as to engage the shoulder ill. The nuts on stud bolts 12 are then evenly released whereby the springs will pick up and stretch the tube shaft about 1%". Two of the struts 86 are then inserted and the stud bolts 12 screwed down until shoulder 88 engages the struts 86 to support the tube, relieving the pressure between rings 6t and shoulder lift on ring 82 while the springs are further compressed until distance F measures 7". The ring nut '82 is again screwed down until it engages the shoulder it. The stud bolts l?! are then released and removed whereupon the springs will again stretch the tube shaft to free the struts t6 and apply the desired tension to the tube shaft. The struts 86 can then be removed and they, together with stud bolts 72, should be put away for use in releasing the spring load or dismantling the tensioner and pump. Split gland it is then positioned as shown and the gland nuts ti tightened to compress the packing in stuffing box "While I have shown and described two specific embodiments of my invention, it will be under stood that these embodiments are merely for the purpose of illustration and description and that various other forms may be devised within the scope of my invention, as defined in the appended claims.

, I claim:

1. In a vertical deep well pump having a shaft tube and an outer column fixedly secured to a pump howl suspended therefrom, the improvement comprising compression spring means for carrying said shaft tube and means above said outer column for adjusting the compression of said springs to apply a determined tension to said shaft tube.

2. In a vertical deep well pump having a shaft tube and an outer column fixedly secured to a pump bowl suspended therefrom, said outer column being suspended from a support member, said shaft tube being supported by a plurality of coil springs, said springs being disposed on a fixed support whereby said springs impart tension to said tube shaft and means for independently compressing said springs to vary the tension im parted thereby to said shaft tube.

3. In a vertical well pump having a shaft tube and an outer fluid conducting column fixedly secured to a pump bowl suspended therefrom, said outer column being attached to and carried by a support means, means above said support for conducting fluid therefrom, said shaft tube extending through said fluid conducting means, compression springs disposed on said fluid conducting means, means fixedly secured to the upper end of said shaft tube, said last named means resting on said springs, and means above said outer column for compressing said springs to vary the tension imparted thereby to said shaft tube.

l, In a vertical well pump having a shaft tube and an outer fluid conductingcolumn fixedly secured to a pump bowl suspended therefrom, the upper end of said outer column being secured to a support, an L-shaped connector mounted on said support and adapted to receive fluid from said column, said shaft tube extending upwardly through said connector, a plurality of compressive springs mounted on said connector and disposed around said shaft tube, a gland nut secured to the upper end of said shaft tube, a ring disposed on said springs and adjustable means connecting said gland nut and said ring.

5. In a vertical well pump having a shaft tube and an outer fluid conducting column fixedly secured to a pump bowl suspended therefrom, the upper end of said outer column being secured to a support, an L-shaped connector mounted on said support and adapted to receive fluid from said column, said shaft tube extending upwardly through said connector, an annular vertical flange on said connector, a horizontally disposed ring having a depending flange, said ring being disposed on said vertical flange with said depending flange fitting inside of said vertical flange, a plurality of vertically disposed studs mounted in said ring, coil springs disposed around said studs and resting on said ring, a ring member slidably mounted on said studs and resting on said springs, a gland nut secured to the upper end of said shaft tube and bolts connecting said gland nut to said slidable ring.

6. In a vertical well pump having a shaft tube and an outer fluid conducting column fixedly secured to a pump bowl suspended therefrom, the upper end of said outer column being secured to a support, an L-shaped connector mounted on said support and adapted to receive fluid from said column, said shaft tube extending upwardly through said connector, an annular vertical flange on said connector surrounding said shaft tube, a ring mounted on said flange, vertically disposed stud members secured to said ring, the upper ends of said studs being interiorly screwthreaded, coil springs around said studs resting on said ring, an apertured ring resting on said springs, a gland nut secured to the upper end of said shaft tube interiorly of said springs, said gland nut having exterior screw-threaded surface at the upper end thereof, stud bolts adapted to extend through said apertured ring and into the upper screw-threaded end of said studs to compress said springs and a ring nut having an outer flange adapted to be screwed around said i gland nut to bring said flange into engagement with said apertured ring to hold said springs in compression and transmit tension therefrom to said shaft tube.

7. In a vertical well pump having a shaft tube and an outer fluid conducting column fixedly secured to a pump bowl suspended therefrom, the upper end of said outer column being secured to a support, an L-shaped connector mounted on said support and adapted to receive fluid from said column, said shaft tube extending upwardly through said connector, an annular vertical flange on said connector, a horizontally disposed ring, said ring being disposed on said vertical flange, a plurality of vertically disposed studs mounted in said ring, coil springs disposed around said studs and resting on said ring, a ring member slidably mounted on said studs and resting on said springs, a gland nut secured to the upper end of said shaft tube and bolts connecting said gland nut to said slidable ring.

8. In a vertical well pump having a shaft tube and an outer fluid conducting column fixedly secured to a pump bowl suspended therefrom, the upper end of said outer column being secured to a support, an L-shaped connector mounted on said support and adapted to receive fluid from said column, said shaft tube extending upwardly 7. through said connector, an annular vertical flange on said connector surrounding said shaft tube, a ring mounted on said flange, vertically disposed stud members secured to said ring, the upper ends of said studs being screw-threaded, coil springs around said studs resting on said ring, an apertured ring resting on said springs, a gland nut secured to the upper end of said shaft tube interiorly of said springs, said gland nut having exterior screw-threaded surface at the upper end 10 Number tured ring to hold said springs in compression and transmit tension therefrom to said shaft tube.

EDGAR.v I. McGEE.

REFERENCES GITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Name Date 1,415,585 Layne- May 9, 1922 1,657,651 Weis Jan. 31, 1928 1,810,332 Wintroath June 16, 1931 1,814,538 Wintroath July 14, 1931 1,922,583 Hollander Aug. 15, 1933

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