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Publication numberUS2556435 A
Publication typeGrant
Publication dateJun 12, 1951
Filing dateApr 27, 1950
Priority dateApr 27, 1950
Publication numberUS 2556435 A, US 2556435A, US-A-2556435, US2556435 A, US2556435A
InventorsMoehrl Kenneth E, Porter Jr Charles B
Original AssigneeLayne & Bowler Inc
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Means for cooling lubricating oil in submerged motors
US 2556435 A
Abstract  available in
Images(2)
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Claims  available in
Description  (OCR text may contain errors)

June 12, 1951 MQEHRL HAL 2,556,435

MEANS FOR COOLING LUBRICATING OIL IN SUBMERGED MOTORS Filed April 27, 1950 2 Sheets-Sheet 1 SUCTION NOZZLE 12% Z. 1 J //vm=ro e/5 tam 5r .e'. hoe/m4 65442158 8 P0 TER JR}.

June 12, 1951 K. E. MOEi-IRL ETAL 2,556,435

MEANS FOR COOLING LUBRICATING OIL IN SUBMERGED MOTORS Filed April 27, 1950 2 Sheets-Sheet 2 m rwrwP twwera 5, 8A1 61/44465 6. 752 J2 Patented June l2, 1951 MEANS FOR COOLIN G LUBRICATING OIL IN SUBMERGED MOTORS Kenneth E. Moehrl and Charles B. Porter, Jr., Memphis, Tenn., assignors to Layne & Bowler, Incorporated, Memphis, Tenn., a corporation of Delaware Application April 27, 1950, Serial No. 158,394

10 Claims.

This invention relates to means for cooling the lubricating oil used with submerged electric motors such as drive the centrifugal pumps largely used in deep well pumping.

In this type of pumping the motor is enclosed in a casing as nearly hermetically sealed as possible against inflow of water, and the casing around the motor is substantially filled with lubrieating oil, and is disposed below the pump with the motor shaft extending through a stufiing box or seal for connection to the pump, or if not so filled, every endeavor is used to divert the oil used in lubrication to the motor bearings, and away from the rotor and stator coils and away from the gap therebetween. The oil within the casing is often stagnant and becomes overheated, and even if circulated, provision is not made for cooling the oil and little or no provision is made for using the oil to cool the rotor and stator coils.

The objects of the present invention are to provide in an enclosed submergible motor, a motor casing substantially filled with lubricating oil, and to provide:

Means for circulating the oil within the motor casing;

Means for circulating the oil in the motor casing through the gap between the rotor and stator coils of the motor;

Means for withdrawing the oil from a sump below the motor and through the gap between the coils and for returning the oil to the sump;

Means for circulating the oil within the motor casing and cooling the oil; and

Means for circulating the oil within the motor casing, and from a sump below the coils, through the gap between the motor coils, cooling the oil and returning the oil to the sump by-passing the gap.

The means by which the foregoing and other objects of the invention are accomplished and the manner of their accomplishment will readily be understood from the following specification upon reference to the accompanying drawings, in which:

Fig. 1 is a sectional elevational view of an electric motor in accordance with our invention showing means for effecting oil circulation and cooling.

Fig. 2 is an elevational view on a smaller scale showing the motor casing and its relation to a tandem type deep well pump.

Fig. 3 is a sectional elevational view of a motor similar to that shown in Fig. 1 with a modified means for effecting the cooling of the oil; and

Fig. 4 is a sectional elevational view of a stuffing box and seal for the motor, showing the oil passage returning from the cooling means passing through the seal.

Fig. 5 is a sectional plan view taken as on the line VV of Fig. 3.

Referring now to the drawings in which the various parts are indicated by numerals: I2 are pump bowls connected in tandem, to form a multistage water pump used in deep well pumping. The bowls enclose pump impellers (not shown) which are driven by a shaft I I. The shaft i4 is a continuation of the shaft of a motor it, which motor is disposed below the pump bowls and connected to and supported from the lower of the bowls by an interposed strainer I8 and a suction nozzle I9, the strainer having wall slots or other openings 20 through which the water which is pumped enters the suction end of the bowls I2.

The motor I6 is of sealed type adapted for submergence and includes a casing which for construction, assembly, and access to the parts,

may be divided into a lower section II, an intermediate section HA, and a seal section IIB. The sections i'I, IiA and HE may be coupled together and secured to the strainer I8 by studs 22 and nuts 22A. The casing is closed at its lower end by a lower head 24, which supports the lower end of the shaft I4 through an annular bearing 26, an annular bearing retainer housing 21, and an annular bearing 28 which journal the shaft. The head 24 preferably includes a depending sump portion 24A which communicates with the casing through openings 2413.

The casing of the section I? is provided at its upper end with an inwardly extending annular flange 30, and the intermediate section IIA has an intermediate head portion 32 which seats on this flange. The head portion 32 has a downwardly extending cylindrical portion 32A which carries at its lower end an upper bearing 34 for the shaft I4. Above the bearing, openings 32B extend through the cylindrical portion 32A, and above these openings the head is chambered out concentrically around the shaft to receive and cooperate with an impeller 36 to form a pump for circulating oil. The impeller is secured to, and driven by, the shaft I4, the openings 32B communicating the section Il with the intake of the impeller.

The section I'IB includes an integral head which may comprise an inwardly extending annular flange 31, a downwardly continuing cylindrical wall portion 31A, and a central head portion 31B, terminating the cylindrical portion, the downwardly extending portion establishing with the casing wall an annular surge chamber 310. The head portion is chambered out concentrically around the shaft to receive an annular flange portion 38A of a seal 38. The flange portion 38A of the seal seats on a gasket 40 disposed in the chambered out central portion 313 of the head and is clamped against the gasket by an annular flange 42 secured by screws 42A. The shaft l4 continues through the seal 38 and upward through the strainer [8 to drive the pump impellers (not shown) in the bowls l2.

The oil pump impeller 36 discharges through a tube 44 to the upper coil 50 of a bank of coils 52 disposed in the strainer section 18 of the water pump. The oil delivered to the upper coil of the bank fiows downward through the coils and a connecting tube 54 into the seal 38 which is shown in sectional elevation in Fig. 4. The seal includes resilient annular sealing rings 56 which are disposed between annular shoes 58 and held in shaft contact by a coil spring 66 disposed between and bearing against the shoes and maintain an annular oil space 62 around the shaft, into which space the tube 54 discharges.

The shaft i l, at least from the seal level to its lower end, has a bore 64 which provides an oil passageway, and at the level of the annular space E2 of the seal has lateral openings 66 establishing communication between the annular space and the shaft passageway. At its lower end the passageway discharges through the axial opening 68 in the bearing retainer 2? into the sump 24A. The motor may be filled with oil through a filling opening Ill. The motor [6 includes an annular stator 12 which is carried by the casing section I1, and a rotor 14 which is mounted on and driven by the shaft 14, the rotor being externally cylindrical and separated from the stator by the usual gap 16, which is open both top and bottom and establishes a connecting passageway from the lower portion of the section I! to the upper portion thereof.

The coil 52 and other passageways, the sump 24A and the motor casing, to a level 31D about half the depth of the surge chamber 310, are filled with oil and the motor put in operation. During operation the oil pump impeller 36 draws oil from the motor chamber and sump 24A and discharges the oil through the tube 44 and the upper coil 50 from which it returns through the bank of tubes 52A.and the tube 54, seal 38 and bore 64 of the shaft, to the sump.

All oil drawn from below the stator-rotor level and the sump, must pass through the gap It between stator and rotor and effect cooling action on the coils. Thereafter the oil is forced through the coil 52, where it is subject to direct cooling action of the water drawn from the well through the strainer i8 into the pump. All the cooled oil returns to the sump and is drawn therefrom through the rotor-stator gap to promote cooling where most needed. Adequate bearing lubrication is also inherently provided by flooding of the bearings.

In Fig. 3 the structure, including the oil pump 36 and parts therebelow, are identical with those previously described and carry the same identifying numbers. 1

Above the pump level a single casing section C may be used, which section is of substantially greater depth than the corresponding two sections previously shown and has associated there'- I31A of correspondingly greater depth, establishing a relatively deep surge chamber [310 which acts as a cooling chamber.

The oil pump 36 discharges directly into the casing section 110. A return tube I54 leads from the surge chamber into the seal 38, which is substantially as shown in Fig. 4 and previously described, but is inverted as regards Fig. 4 to facilitate connection of the return pipe. In this form of the device, primary reliance for cooling of the oil is placed on contact of the oil with the wall of the casing section. Preferably the oil pump 36 discharges through a short discharge tube I56 which is arcuately curved to discharge substantially circumferentially around the casing wall and may be spiralled slightly upward. The motor section is coupled to the pump bowls through a strainer section which may be identical with the strainer section l8 of Fig. 2, or be a section H8 of modified shape as indicated in Fig. 3. In the claims the surge chamber 31C of Fig. 1, or [31C of Fig. 3 will be also referred to as an expansion or cooling chamber.

It will be understood that many of the details of construction of the motor section, as evidenced by differences in detail of the sections shown in Fig. 1 and Fig. 3, may be varied without departing from the spirit of our invention, and that except where a detail is definitely set out in any claim or claims such detail may not be read into such claim or claims.

We claim:

1. In a deep well pump which includes pumping means, an intake section below and supported from said pumping means and a sealed type submersible motor substantially filled with oil supported by said intake section, said motor including a casing, a vertical shaft, a rotor, and a stator, said casing having a lower closure head including a depending sump, an upper head through which said shaft extends to driving engagement with said pumping means, and an intermediate head dividing said casing into a motor section and an expansion section; said upper head including a seal surrounding said shaft and substantially hermetically sealing said casing; oil circulatin means including a housing formed in said intermediate head around said shaft; a pump impeller secured on said shaft, disposed in and cooperating with said housing to form a centrifugal pump, said impeller having an intake facing and communicating through said intermedi ate head with said motor section, and said housing having a discharge opening in said expansion section; a tubular cooling coil disposed in said intake section, a tube communicating said discharge opening with said coil, and a return tube communicating said coil into said seal; said shaft from said seal to its lower end, having a central bore and having openings communicating the interior of said seal with said bore; said lower head having a central opening into said sump underlying said shaft bore and additional openings communicating said sump and motor section.

2. In a deep well pump which includes pumping means, an intake section below and supported from said pumping means and a sealed type submersible motor substantially filled with oil supported by said intake section, said motor including a casing, a vertical shaft, a rotor, and a stator, said casing having a lower closure head including a depending sump, an upper head through which said shaft extends to driving engagement with said pumping means, and an in- 'termediate head dividing said easing into a motor section andan expansion section; said upper head including a seal surrounding said shaft and substantially hermetically sealing said casing; oil circulating means including a housing around said shaft carried by said intermediate head; a pump impeller secured on said shaft, disposed in and cooperating with said housing to form a centrifugal pump, said impeller having an intake facing and communicating through said head with said motor section, and said housing having a discharge opening in said expansion section; a tubular cooling coil disposed in the path of water drawn into and through said intake section by said pumping means, a tube communicating said discharge opening with said coil, and a return tube communicating said coil into said seal; said shaft from said seal to its lower end,

having a central bore and having openings communicating the interior of said seal with said bore; said lower head having a central opening into said sump underlying said shaft bore and additional openings communicating said sump and motor section.

3. In a deep well pump which includes pumping means, an intake section below and supported from said pumping means and a sealed type submersible motor substantially filled with oil supported by said intake section, said motor including a casing, a vertical shaft, a rotor, and a stator, said casing having a lower closure head ineluding a depending sump, an upper head through which said shaft extends to driving engagement with said pumping means, and an intermediate head dividing saidcasing into a motor section and an expansion section; said upper head including a seal surrounding said shaft and substantially hermetically sealing said casing; oil circulating means including a housing around said shaft carried by said intermediate head; a pump impeller secured on said shaft, disposed in and cooperating with said housing to form a centrifugal pump, said impeller having an intake facing and communicating through said head with said motor section, and said housing having a discharge opening in said expansion section; a tubular cooling coil disposed in said intake section in the path of water drawn into and through said intake section by said pumping means, a tube communicating said discharge opening with said coil, and a return tube communicating said coil into said seal; said shaft from said seal to its lower end, having a central bore and having openings communicating the interior of said seal with said bore; said lower head having a central opening into said sump underlying said shaft bore and additional openings communicating said sump and motor section.

4. In a deep well pump which includes pumping means, an intake section below and supported from said pumping means and a sealed type submersible motor substantially filled with oil supported by said intake section, said motor including a casing, a vertical shaft, a rotor, and a stator, said casing having a lower closure head, an upper head through which said shaft extends to driving engagement with said pumping means, and an intermediate head dividing said casing into a motor section and an expansion section; said upper head including a seal surrounding said shaft and substantially hermetically sealing said casing; said casing enclosing an oil pump carried by said intermediate head and driven by said shaft; said pump including an intake communieating with said motor section, and a discharge opening in said expansion section; a tubular cooling coil carried by said intake section in the path of water drawn into said intake section of said pumping means, a tube communicating said discharge opening with said coil, and a return tube communicating said coil into said seal; said shaft from said seal to its lower end, having a central bore and having openings communicating the interior of said seal with said bore; said lower head having openings communicating said shaft bore and said motor section.

5. In a deep well pump which includes pumping means, an intake section below and supported from said pumping means and a sealed type submersible motor substantially filled with oil supported by said intake section, said motor including a vertical shaft, a rotor and a stator,

and a casing having a lower closure head including a depending sump, an upper head through which said shaft extends to driving engagement with said pumping means, and an intermediate head dividing said casing into a motor section and an expansion section; said upper head including a seal including axially spaced sealing rings surrounding said shaft and substantially hermetically sealing said casing; oil circulating means which includes a housing forming part of said intermediate head; a pump impeller secured on said shaft disposed in and cooperating with said housing to form a centrifugal pump, said impeller having an intake facing and communicating with said motor section, and said housing having a discharge opening in said expansion section; a tubular cooling coil disposed in said intake section, a tube communicating said discharge opening with one end of said coil, and a return tube communicating the opposite end of said coil into said seal; said shaft from said seal to its lower end having a central bore and having a lateral opening communicating the interior of said seal with said bore; said lower head having openings communicating said sump and said motor section, and an opening into said sump underlying said shaft bore.

6. A submersible motor which includes a sealed oil filled casing and a vertical hollow shaft journalled in said casing; said casing having a closure head at its lower end, an upper head carrying a seal through which said shaft projects, and an intermediate head dividing said casing into motor and cooling chambers, a cylindrical rotor mounted on said shaft, and a casing carried annular stator around and separated from said rotor by an annular gap interconnecting upper and lower portions of said motor chamber; oil circulating means including a housing carried by said intermediate head, and having a discharge opening into said cooling chamber, an impeller mounted on said shaft and disposed in said housing, said impeller including an intake opening leading from the upper portion of said motor chamber, said seal including a shell having an opening therethrough into said cooling chamber, and said shaft having lateral openings from said seal into said hollow shaft.

'7. A submersible motor which includes a sealed oil filled casing and a vertical hollow shaft journalled in said casing; said casing having a clo- Sure head at its lower end, an upper head carrying a seal through which said shaft projects, and an intermediate head dividing said easing into motor and cooling chambers, a cylindrical rotor mounted on said shaft, and a casing carried annular stator around and separated from said rotor by an annular gap interconnecting upper and lower portions of said motor chamber; oil

circulating means including a housing carried by said intermediate head, and having a discharge opening, a tube leading arcuately away from said opening and terminating in substantially tangential relation to the shell of said cooling chamber, an impeller mounted on said shaft and disposed in said housing, said impeller including an intake opening leading from the upper portion of said motor chamber, said seal including a shell having an opening therethrough into said cooling chamber, and said shaft having lateral openings from said seal into said hollow shaft.

8. A submersible motor which includes a sealed oil filled casing and a vertical hollow shaft journalled in said casing; said casing having a closure head at its lower end, an upper head carrying a seal through which said shaft projects, and an intermediate head dividing said casing into motor and cooling chambers, a cylindrical rotor mounted on said shaft, and a casing carried annular stator around and separated from said rotor by an annular gap interconnecting upper and lower portions of said motor chamber; oil circulating means including a housing carried by said intermediate head, and having a discharge opening into said cooling chamber, an impeller mounted on said shaft and disposed in said housing, said impeller including an intake opening leading from the upper portion of said motor chamber, said seal including a shell having an opening therethrough, a tube connected to said shell and leading from said opening upward to desired oil level in said cooling chamber, and said shaft having lateral openings from said seal into said hollow shaft.

9. A submersible motor which includes a sealed oil filled casing and a vertical hollow shaft journalled in said casing; said casing having a closure head at its lower end, an upper head carrying a seal through which said shaft projects, and an intermediate head dividing said casing into motor and cooling chambers, a cylindrical rotor mounted on said shaft, and a casing carried annular stator around and separated from said rotor by an annular gap interconnecting upper and lower portions of said motor chamber; oil circulating means including a housing carried by said intermediate head, and having a discharge opening, a tube leading arcuately away fromsaid opening and terminating in substantially tangential relation to the shell of said cooling chamber, an impeller mounted on said shaft and disposed in said housing, said impeller including an intake opening leading from the upper portion of said motor chamber, said seal including a. shell having an opening therethrough, a tube connected to said shell and leading from said opening upward to desired oil level in said cooling chamber, and said shaft having lateral openings from said seal into said hollow shaft.

10. A submersible motor which includes a sealed casing and a shaft journalled in said casing, said casing having a closure head at one end, an opposite head carrying a seal through which said shaft projects, and an intermediate head dividing said casing into motor and cooling chambers, a cylindrical rotor mounted on said shaft, and a casing carried annular stator around and separated from said rotor by an annular gap interconnecting opposite portions of said motor chamber; pumping means, within said casing, driven by said shaft, said means including an intake from said motor chamber adjacent said intermediate head and a discharge opening into said cooling chamher, said shaft extending from said seal carrying head to adjacency with said closure head, having a co-extensive bore and lateral openings into said bore adjacent said seal carrying head, said openings and said bore establishing return flow from said cooling chamber into said motor chamber adjacent said closure head.

KENNETH E, MOEHRL. CHARLES B. PORTER, JR.

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

UNITED STATES PATENTS Number Name Date 1,968,566 Moran July 31, 1934 2,002,916 Mendenhall May 28, 1935 2,043,236 Conant June 9, 1936 2,280,087 Hollander Apr. 21, 1942 FOREIGN PATENTS Number Country Date 544,930 Great Britain May 4, 1942

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Classifications
U.S. Classification417/367, 417/368, 310/157, 310/90, 310/54, 417/423.11, 310/87
International ClassificationH02K9/19, F04D29/06
Cooperative ClassificationF05B2240/61, H02K9/19, F04D29/061
European ClassificationH02K9/19, F04D29/06P