US2311805A

US2311805A - Closure for submersible pumping units

Info

Publication number: US2311805A
Application number: US384882A
Authority: US
Inventors: Yost Lloyd
Original assignee: AO Smith Corp
Current assignee: AO Smith Corp
Priority date: 1941-03-24
Filing date: 1941-03-24
Publication date: 1943-02-23
Anticipated expiration: 1960-02-23

Description

FEE). 23 @943. i (@53- CLOSURE FOR SUBMERSIBLE PUMPING UNITS Filed March 24, 1941 FIG...Z.,

24 mul Z5 5/ j; 54 15 57 z 5' 36 20 /9 w /7 1e 5 l7 7 z 4 5 Lloyd Ybsi" INVENTOR.

AT TURN E \f trio motor 0, preferably s.

Patented Feb.23,1 943- Lloyd Yost,

Lcs Angeles, Calif assignmto A 0.

Smith Corp M lwaukee, Wis., a corpora tlon 0! New York Aupllcation March 24, 194i, Serial No. 384,882 8 Shims. (Qi- 1.72-36) This invention relates to s. closure for the upper end of submersible pumping units.

Pumping units of the kind here under consid eration have an electric motor reoeivim electrical energy through e. cable and are desmrled to be submerged in the liquid to be pumped, usually in on oil or other well.

Que or the objects of the invention is to provide o closure for the upper end of such a unit with an improved seal between the cable and the unit.

Another object of the invention is to provide 9, closure which is readily assembled and which effectually protects the electric motor a other ports of the mechanism trout damage by entrees-e of the liquid being summed.

These and other objects of the invention will be clear from the following detailed description and the accompanying wiuch:

Figure l is s. vertical section through the upper end of e, pumping unit constructed in accordance with the invention; and

Fig. 2 is e similar view showing the relative positions of the before the assembly is completed.

In accordance with the invention prin cipal phase 9. separate chamber is provided icetween the end of the motor chamber end the end oi the housing for receiving the end of the electric cable and its several separate conductors, the chamber being sealed from the motor chamber and from the outside to prevent fluid from irriur' ing either the end of the cubic-or conductors.

Referring to the drawing, and at first to Fiture 1 which shows the parts assembled, the elec three phase induction motor, has a stetora in a fluid tight shell. e joined by weld d to e concentric sleeve 3. The upper bearing 6 for rotor i is held in e bearing support 8 which is secured in position by e strep ring 9 seated in a. groove iii cut in sleeve By means of mechanism which is housed in the lower part of the pumping unit, but which tor-ms no part of this invention and is not shown in the drawing, the motor forces it upward in the annular space between the outer casing or bone mg I! and the inner assembly consisting of the motor shell 1, sleeve 5, I and the other parts secured to them.

The motor leads ii are soldered to tapered conducting pins I3 secured in a blocl: H of Bakelite or other suitable material so as to form a fluid tight Joint with the extends upward from snap the lower end or a packing ring 9 to abut against ring I which may be drives a. pump which. takes. liquid from the well and block. A spacer sleeve H5 mode of neoprene or other material resistant to the action oi oil and suitable tor A shoulder it on molded bloclr it is forced against the urmer end of the packing ring it by on e Belly threaded clampim; ring SE3 which engages internal screw threads is in sleeve 5. The resultant compression of packing between sleeve 5 and molded block it efZectuell-y seals the motor compartment against entrance from the outside and prevents the sec from the motor compartment. A three 213 provided to lock the clamp 68..

A short sleeve is screwed into sleeve 8 to make an oil tight joint r upper end to head 22. The mono passes into the head through use its 25. pecking rings 2% of neoprene or ctr: s materiel, and washers A. small sessegew extends from between the packing rings outside or the head. This pessegewey porn the escape of air trapped between the 1' rings 25 when the packing" compress screwed into threads 28 to compress rings and form e. liquid tight seal between cable and head. The passage 23 may also used in testing the packing against leakage by e, lug through the passage on air pressure of s cient magnitude, usually about 5%- lies. on square inch.

After the seal has been made by compressing the packing, the passageway is plugged with plug 29 which may in addition be welded, over to insure against leakage. The seal formed moi/sud the cable prevents leakage of oil into the head along the cable. Inside the head the cable cope rates into its constituent conductors which soldered or otherwise electrics. r cormected t The annular space between the head 22 on outer casing H is sealed by means of o, rim packing rings 32, washers 3S, and packing to pressor 86. Ring 31 is secured against lougit rial movement by means of screws pass 1 through the outer casing it and welded over prevent leakage. The packing rings 33 are com pressed between the head and casing by screwing the packing compressor 34 into threads 38 in the end of the casing.

Oil that has been pumped by the unit from the well into the annular space between. the

inner assembly and outer casing ll passes into head 22 through opening 31 and then into the tueliilug 88 which conveys it upward through the w The manner in which the assembly is made will be clear from Fig. 2. When the motor assembly is complete and the parts that areto go below it are secured in place, spacer sleeve l5 and packing ringli are inserted in sleeve 5 and the motor leads l2 are brought out beyond the end of the sleeve where they can readily be soldered to pins I3. A length of tubing 38 is screwed into head 22 and additionally secured, if desired to insure against leaks at the threaded joints, by weld 39. The cable 23 is entered into the head, sealed as previously described, and the end of the cable where the conductors are separated is taped or. finished in any appropriate fashion as indicated at 40.

Th means used to seal the annular space be tween the head and outer casing are positioned about as shown and the conductors from the cable are then passed through sleeve 2!, locking ring 20, and clamping ring l8, and soldered or otherwise electrically connected to pins l3. It will be clear from the drawing that suflicient space is available to done.

The molded block it is then seated ln'sleeve 5 with its shoulder l'l engaging packing rnig l6. Clamping ring. is and locking ring are screwed home to close the upper end of the mo-.

tor compartment and complete the-first seal designed to prevent leakage into or out of the motor chamber. Sleeve 2| is then screwed into sleeve 5 to make an oil tight joint with the tapered end of sleeve 5 seated against the correspondingly tapered surface on sleeve 2!. As the sleeve 2| has not yet been welded to head 22 it is clear that the threaded joint can be made up without twisting conductors 30.

The head 22 is then welded to sleeve 2| by. This completes the upper end of the. inner assembly. It will be seen that the cable weld H.

is packed where it passes through the head so as to prevent oil leakage along the cable, and that, in addition, the block 14 separates the space immediately below the head from the motor compartment. If either joint fails while the other remains tight, the motor compartment is eilectively protected against the entrance of oil. It is only when both fail that oil can leak into the motor or gas escape in undesirable quantitles.

The lower sections of the inner assembly that are to be connected below the motor are secured in place, if this has not previously been done;

and the entire inner assembly is slipped into buter casing ii. I The lower ends of the casing and inner assembly are joined by means which form no part of thisinvention.

The upper end of the annular space .between the casing and inner assembly is then packed. Ring 3| is slipped down and secured by screws 35 through the outer casing which may be welded over on the outside to prevent leakage of oil. Packing rings 32- and washers 33 are put in position and packing compressor 34 is screwed down to compress the packing rings and form a fluid tight seal.

The head 22 and block' it provide a sealed compartment between them and in which the end of cable 23 is broken down into the flexible leads 30. By reason of the sealing of this compartment there is no danger of the compressed gas or liquid in the motor compartment escaping and entering the end of the cable, and there is also no danger of fluid entering the compartpermit this to be readily ment from the outside and insulation on the leads 30."

I claim:

deteriorating the 1. In a device of the class described, an eiecblock closing said sleeve and substantially spaced from the end of the motor, a packing ring disposed in compression to seal the Joint between said block and sleeve, means to secure said block in place, a head spaced from said block and welded to the end oisaid sleeve to close the same and having an opening therein for receiving an electrical cable, packing means for sealing said cable in said opening-said cable having flexible leads of substantial length on its inner end, and means extending through said block for connecting the respective motor leads to the corresponding cable leads for supplying the motor with electricity, the flexibility of the I leads serving to facilitate assembly of the block and head after connection of the leads, and the several seals serving to prevent leakage of fluid either into or out of the motor compartment in said sleeve.

2. In a device of the class described, a tubular casing, a motor compartment therein, means for sealing the end of said compartment in said casing against escape of fluid therefrom, a head closing said casing and providing a second compartment between the head and the end of said motor compartment, a cable extending through said head and sealed therein to prevent leakage of fluid from the outside into said second compartment, and flexible leads at the inner end ofmotor to supply electricity thereto.

3. In a device of the class described, a motor compartment, a second compartment at the end thereof and having an electric cable extending into the same, the end of said cable being separated into its constituent leads in said second compartment, means connecting said cable leads to corresponding leads from the motor, and

means sealing said second compartment to make the same fluid tight.

4. In a submersible pumping unit, a head, an electric cable passing through the head, packing rings in an annular space between the head and cable, screw threaded means to compress the packing rings and form a fluid tight seal between the head and cable, a passageway extending from between the packing rings to the outside of the head to provide for the escape of air as said packing rings are compressed during assembly,

and means to plug the passageway after the packing rings have been compressed.

5. In a submersible pumping unit, an electric motor in a tubular container, motor leads electrically connected to, electric conductors extending through an insulating block in fluid tight contact therewith, packing means to form a fluid tight joint between the block and the tubular motor container, a sleeve, a threaded joint between the sleeve and motor container, 8; head welded to the sleeve, an electric cable extending through the head with conductors electrically connected to the conductors passing through the insulating block, packing rings in an annular space between the head and cable, and screw threaded means to compress the packing rings and form a fluid tight seal between the head and cable. 7

6.111 a submersible pumping unit, a motor chamber, an insulating block closing the end of said chamber and having an oil resistant rubber packing sealing the same, metallic electrical connectors passing through said block and secured therein, motor leads secured to said connectors on the inside of said block, and an external supply cable secured to said connectors on the outside of said block.

'7. In a submersible pumping unit, a motor chamber, an insulating block closing the end of said chamber, and a plurality of tapered pins of electrically conductive metal fitting and secured in correspondingly tapered openings in said block and extending therethrough for connecting an external supply cable to the motor leads.

8. In a submersible pumping unit, an electric motor in a tubular container, motor leads electrically connected to electric conductors extending through an insulating block in fluid tight contact therewith, packing means to form a fluid tight joint between the block and the tubular motor container, a sleeve extension for the container, a threaded joint between the sleeve and motor container, a head welded to the sleeve, an electric cable extending through the head with conductors electrically connected to the conductors passing through the insulating block, packing rings in an annular space between the head and cable, screw threaded means to compress the packing rings and form a fluid tight seal between the head and cable, a passageway extending from between the packing rings to the outside of the head to permit escape of entrapped air when the packings are compressed, and means to plug the passageway.

LLOYD YOST.