US2722892A - Submerged liquid pump - Google Patents

Description

1955 H. c. FRENCH SUBMERGED LIQUID PUMP INVENTOR. $46M BY $2M/&&MW 2/ A TTOEA/EYS- Filed July 9, 1952 United States Patent Ofi ice SUBMERGED LIQUID BUMP Henryl'C. French, Elm Grove, Wis assignor to'The Morrison Company, Milwaukee, Wis a corporation of Wisconsin Application- July 9, 1952, Serial N 0. 297,854

2' Claims. "(CL .Ill3---87) The present =invention relatesrin general to improvemeats in the construction and-.operation ofrsubmersible .rot-ar y liquid pumps, and is-a continuation tin ,part-nf any copending application Serial No. 190,709, filed @ctober 18, 1950, now abandoned.

The :mainrobject -:of :my invention \is ato provide various improvements -in submerged :rotary .liquid.p1unps, wherebytheconstruction andvinstallati'on thereof .is facilitated, while the operating efficiency is enhanced to a-maximum.

'An :important object of wthe :invention :is to; provide :a simple, durable and" compact electricrnrotor driven liquid pumping unit especially adapted =to be submerged within the source of liquid supply.

Another important object of this invention is \to provide an'efiicient motor -..driven pump assembly .iIYWhlGh the "various parts are well protected against rexcessi-ve wear or other damage during normal operation; and wherein these part-s may -.be readily ..manufactured, .as- .sembled, or dismantled.

A :further :important .object '.of any gpresent zinvention is .to provide an improved rotary .liquid pumping device comprising relatively few simple parts which \can be .easily machined .and .united :to produce a -.well .balanced structure.

.Still .anotherimportant object \of the invention is to ,provide. a thighrspeed trotary, motor .drivempump .of limited dimensions and .free from external projections, thus adapting .it .for convenient insertion or removal with :respect to wells of. small diameterandof-varying .depths.

.An .additional important object of the present .inven- .tionds :to provide. a :self .cooled .motor .driven :pump unit ihaving ample and well protected bearings, .and which is operablelforlong periodsof time with minimum attention and atmoderate cost.

Another important .objectof thisinvention .is to .pro- -vide various improvements in pumps :of .t'hetype .shown and described inmy copending-application.above referred to, whereby the motor parts and bearings vof such .units are more thoroughly protected and obstruction to ffiow o'f't'he liquid is minimized.

"These and other more specific objects and advantages -of the invention will be :apparent .from theafollowing description.

A clear conception of the presentimprovements and of the construction and operation of a typical -motor propelled pumping unit embodying the invention, .may 'be had by referring to-the .drawing accompanying ,and forming a part of this specification in which like reference characters designate the .same .or similar .parts "in the various views.

Fig. '1 'is an outside view of one .offthe irnprovedlec- "tric motor driven-two. stage "rotarypumps with 'thenpper portion of the tube forcon'fining the .motor-tenergizing wires omitted; i I

Fig. 2 is a central vertioalllongitu'c'linalsection through the same-unit, taken-at. r'ightanglesrelative (dim view of'Fig. '1;

Fig. 3 is a top view of the same assemblage, a transof thetbearings .11, 12 .13, 14 and .19 are-normally entering the pump,

meme sectionrhavingcbeen takenithrough1the*upper liquid :disch'argeqaipe;

4 is a :transverse .Jsection through the pumping zunit,italcenalong thedine 4"4 o'f Fig. 2; and

:5 is a stop ViCW 0f itheiself-cleaning thrust 'bearing :forthemainsshaftandiwhichis located inthe pump in- .takesspace.

While .the [invention :has ibeen illustrated and described :herein :as beingzadvantageously applicable to a submerfisible "two :stage rotary electric imotor f'driven -water pump of a speeific type, it is not my desire or intention to unnecessarily restricttheiuseiof all of theimproved'features :by virtueiof this limitedsshowingpandit is also contemrp'late'd Lthat specific descriptive (terms remployed herein be given ithe broadest possible interpretation. consistent with .the disclosure.

Referring *to rthe fdrawing, the improved submersible electricrmotor propelled liquid pump illustrated therein icomprises :in genera'l, :a main frame including a lower Phase section 7, an upper :composite section 8, and an iinterrne'diatesbearingisection=9g a singletcontinuous shaft 1 6; zanda pair :of rotary pump impellers 1 7, 18 also se- :eurerl tOf thevunitarysshaft i10 withintlre upper frame sec- .tioni8rnntopposite sidesrof the'upp'crmost bearing 12.

The lower-r'orl base section '7 "of the=frame within which the :guide bearing '11 "i'scon'fined, may be provided with supporting pads 2-21 and with a central "removable plug 22 for permitting free-access "to the "bearing 11 and to ttheflowerfenfl:iof the shaft 10,. and the section 7 is pre'f- -:erably 'embrac'edI by-a protective-guardring 23, as shown :in Eigs. '1 a'n'dfiQ. Thewpper-composite frame section 8 comprises a pair-'iof pump'impeller housing rings' 24, '25 each ha vingi-thereon :an inwardlyeXtending radial progjectionllzfi; zan aiijoining' pair (Sf- casings 27, 28, located between the rings 24, 25 and coacting with-=eaeh=other to Eform an annular vman'ifold chamber '29 communicable 'withtthe impellers T17, 18;:an upper discharge *head 30 rfor the high pressure pump impller 1B; and a lower zinlet head-31 for the low pressure pump impeller 17. The guideabearing l il is mounted in the manifold casring st27, 28, while the guide bearing'13 is likewise mount- :intthezpump inlet head 31, and all of these pump ihousing :"elem'ents constituting the "upper frame section 8 ofithe-univare normally'firmly but detachably and adrjnstably Funited iby cap screws 32 or the like.

The intermediate or -thrust bearing section 9 of the main frame, 'and within which-the guide bearing 14 and rthethrust bearing 19'are mounted, is also normally firmly =but'detachably-secured to'ithe lower endhead 31 of the :pump by other capscrews'ifi, and 'both the' end head 31 and the frame 5section9 are *surrounded'by an annular liquid inlet screen 35 of approximately the same external :diameter'as that .of the pump casing, see Figs. 1 and 2. .The fthrust bearing 219 which is exposed to the liquid is formed of special wear resisting material an'd wi'th radial-indentations 36 as illustrated in 'Fig.:-5, andcoacts with a-thrust'collar 37 secured to the shaft 10 by screws 38 'as shown in Fig. 2. This special formation "ofthe thrust bearing 19 acts as a spinner and tends to prevent sand and other gritty substances from lodging thereon. The peripheral skirt depending from .collar 37 also-serves to prevent deposit of silt and the .like'on the thrust ebearing. "Since-:no 'efiort is made to seal the. bearings leakage willttakmplace and, as aresult,

exposed to and are lubricated by the fresh liquid within which the unit is submerged. The thrust bearing shown serves as a shaft seal also and prevents constant changing of the water around the rotor and therefore prevents silt from accumulating on the rotor.

While the rotor 15' of the propelling motor is also exposed to the submerging liquid, the motor stator or field 16 is not thus exposed and must be protected against exposure to water which may have objectionable particles therein. The stator field 16 is therefore sealed within an annular space 40 which may be filled with pure insulating material such as oil, and which is formed by inner and outer concentric thin- walled tubes 41, 42 welded or otherwise sealingly secured to lower and upper rings 43, 44 having threaded lugs 45, 46 respectively, firmly secured thereto, see Fig. 2. These tubes 41, 42 are preferably formed of thin non-magnetic and noncorrosive sheet metal such as stainless steel, and the inner tube 41 loosely embraces the motor rotor 15, while the outer tube 42 has approximately the same external diameter as that of the screen 35 and of the guard ring 23 of the lower frame section 7. The frame section 7 is normally rigidly attached to the lower lugs 45 by cap screws 47 while the cap screws 34 which fasten the pump casing to the intermediate frame section 9 also firmly secure this section 9 to the upper lugs 46, thus firmly uniting the successive parts of the unit all of which have substantially like external diameters.

Since the material within the space 40 is subject to some expansion and contraction, or breathing, and current conductors 49 for energizing the electric motor must also be connected to the field windings, it is necessary to provide means for permitting such breathing and for leading the conductors into the space 40 without permitting water to enter the latter. This important feature of the present invention is accomplished by providing an elongated flexible water-proof tube or conduit 50 the lower end of which is sealingly attached to the upper seal ring 44 by a water-tight fitting 51 and the upper end of which is sealed by a plug 52, and through which the conductors 49 extend. The lower portions of this tubular conduit 50 may be held close to the frame section 8 and protected by a U-shaped guard plate 53, and the conduit 50 should be of sufficient length to extend well above the level of the liquid within which the pump is submerged.

In order to complete the assemblage and to permit the assembled motor propelled pump unit to be readily installed and submerged within a source of liquid supply such as a well of limited diameter, the vertical pump outlet or discharge pipe 55 is secured to and is communicable past a non-return check valve 56, with a liquid outlet cap 57 which is also firmly secured to the pump housing frame section 8 by the clamping screws 32. This cap 57 is dome shaped as shown in Figs. 2 and 3, and also has an external diameter approximately equal to that of the pump housing; and the conductor conduit guard plate 53 may be attached to the cap 57 by screws 58. The rigid liquid discharge pipe 55 thus serves as an effective means for installing or removing the unit and for normally suspending it in a source of liquid supply, and this pipe may be of any suitable length and diameter.

The details of construction and the mode of assembling and of adjusting the improved two stage pump constitute the subject of my copending application Serial No. 190,709, filed October 18, 1950, now abandoned, and therefore will not be repeated herein. However, when the improved rotary electric motor driven pumping unit has been properly constructed and assembled as hereinabove described, and the upper suspension cap 57 has been attached to a discharge pipe 55, the latter may be readily utilized to lower and to submerge the motor and pump within a well or other source of liquid supply from which water is to be pumped. The electric motor may then be operated at will by actuating a control switch associated with the conductors 49 beyond the upper end of the conduit 50, thereby causing the motor rotor 15 to rotate the shaft 10 and the pump impellers 17, 18 at high speed. Liquid will then flow through the screen 35 and will pass through the impeller 17, manifold chamber 29, and impeller 18 in succession, and will be delivered past the check valve 56 and into the outlet pipe 55 at relatively high pressure and in the form of a constant stream.

Whenever the motor is stopped, the valve 56 will close automatically and the pipe 55 will thus be maintained filled with liquid. All of the bearings 11, 12, 13, 14, 19 being constantly submerged in the liquid, are effectively lubricated and cooled, and the improved construction of the thrust bearing 19 prevents solid matter from lodging thereon or on the rotor. The formation of the pump is also such that the pressures acting upon the impellers 17, 18 are balanced thus relieving the thrust bearing 19 from excess pressure other than the weight of the rotary elements. The insulating material confined within the chamber 40 in which the motor field 16 is housed, will be cooled by the liquid surrounding the casing tube 42, but the chamber 40 will always be sealed against possible entry of water, by the tubes 40, 41, end disks 43, 44, fitting 51, and by the riser conduit 50.

The several frame and casing sections of the unit, all having approximately the same relatively small external diameter and being substantially devoid of external projections, make it possible to easily lower the unit into a well of small diameter and to likewise remove the same, without obstruction. The several parts of the pump may also be assembled or dismantled by manipulating only a few screws, and access to the lower guide bearing 11 for inspection or removal of sediment may be gained by withdrawal of the plug 22. The formation of the stator casing with rigidly attached lugs 45, 46 with which the cap screws 47, 34 coact, provides simple means for uniting the lower and intermediate frame sections 7, 9 in perfect axial alinement, and the longer cap screws 32 also serve to effectively unite the pump housing section 8 with the intermediate frame section 8 and with the discharge cap 57.

From the foregoing description of the construction and operation of the improved motor driven unit, it will be apparent that the present invention provides a submersible high speed deep well pump assembly which besides being simple and compact in structure may also be quickly and conveniently installed in liquid supply sources of limited dimensions. The improved motor and pump housing is composed of parts which may be readily machined and assembled or dismantled, and which normally elfectively conceal and protect the more delicate parts of the unit. The breathing seal for the motor stator including the riser conduit 50, is especially important and positively prevents objectionable foreign matter from entering the chamber 40, and all parts of the device are normally cooled by the liquid in the source of supply. The invention has proven highly satisfactory and successful in actual use, and the pumps while being especially adapted for deep well service may be used for other purposes as well.

It should be understood that it is not desired to limit this invention to the exact details of construction and operation of the motor driven two-stage submersible pumping unit herein specifically shown and described, for various modifications within the scope of the appended claims may occur to persons skilled in the art.

I claim:

1. A submersible pump comprising, an elongated assembly, an electric motor in the lower portion of the assembly, a pump in the upper portion of the assembly, a water intake between the pump and the motor, means sealing the motor stator against entrance of water, a shaft in said assembly, the motor rotor being mounted on the shaft, the pump impeller being mounted on the shaft, said rotor being submerged in water and lubricated by the water, a thrust bearing and seal unit between said intake and said motor to support the shaft and to prevent interchange of water in the rotor, said unit including a bearing member fixed in said assembly and having a bearing surface surrounding the shaft and an annular bearing surface facing upwardly, a bearing collar fixed on the shaft and having an annular hearing surface overlying and in contact with said annular bearing surface on said bearing member, one of said annular bearing surfaces being radially grooved to provide an outwardly diverging space between the annular bearing surfaces.

2. A submersible pump comprising, an elongated assembly, an electric motor in the lower portion of the assembly, a pump in the upper portion of the assembly, a water intake between the pump and the motor, means sealing the motor stator against entrance of water, a shaft in said assembly, the motor rotor being mounted on the shaft, the pump impeller being mounted on the shaft, said rotor being submerged in water and lubricated by the water, a thrust bearing and seal unit between said intake and said motor to support the shaft and to prevent interchange of water in the rotor, said unit including a bearing member fixed in said assembly and having a bearing surface surrounding the shaft and an annular bearing surface facing upwardly, a bearing collar fixed on the shaft and having an annular bearing surface overlying and in contact with said annular bearing surface on said bearing member, said collar being provided with a depending peripheral skirt which projects downwardly past the level of said annular bearing surface of said bearing member, and one of said annular bearing surfaces being radially grooved to provide an outwardly diverging space between the annular bearing surfaces.

References Cited in the file of this patent UNITED STATES PATENTS 1,347,732 Cooper July 27, 1920 1,974,183 Gunderson Sept. 18, 1934 2,120,914 Vogel June 14, 1938 2,255,545 Hait Sept. 9, 1941 FOREIGN PATENTS 204,956 Switzerland Dec. 16. 1939 323,658 Italy Jan. 2, 1935 885,658 France Sept. 22, 1943

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