US2363420A

US2363420A - Submersible pump

Info

Publication number: US2363420A
Application number: US441844A
Authority: US
Inventors: Howard Giles Philip Eliot
Original assignee: Individual
Current assignee: Individual
Priority date: 1941-05-05
Filing date: 1942-05-05
Publication date: 1944-11-21
Anticipated expiration: 1961-11-21

Description

Nov, 21, 1944. Gf P. E. .HOWARD SUBMERSIBLE PUMP Filed My 5'.v 1942 3' Sheets-Sheet l G. P. E. HOWARD SUBMERSIBLE PUMP Nov. 21, -1944.

Filed May 5, 1942 3 Sheets-Sheet 3 According to the invention, in a submersible system.

` with ud outside the bottom-pump bearings f ring which is pressed axially, by the inherent resilience o! the bellows, against aflange mounted Patented Nev'. 21,1944 f UNITED STATES PATENT oFEicE suminsmLE rum,

Giles Philip Eliot Howard, Coleshlll, Amersham, England Application my s. 1942, serial No. 441,344 s In Great Britain May 5, 19 41 11 claims. (ci. sass-zaga) concerned with the problem of ensuring long lite 5 ofthe bearings of the unit in working conditions which do not admit of normal lubrication and attention.

In my co-pending application I have described an arrangementv whereby the bearings both of the pump and of-the motor are lubricated with liquid is essential for satisfactory operation under the liquid (usually water) in which the pump full illm conditions. of a Journal bearing, parunit is submerged, said arrangement comprisingv ticularly if the liquid is water which has, even means for maintaining the-liquid nlm 1n' the at normal temperatures, a very low viscosity. It bearings at a suiiiciently low temperature to en# 15 is common knowledge that the load capacity oi sureadequateviscosity for the Purpose in view. a bearing is proportional to the viscosity oi the with the arrangement disclosed in the said aplubricant. and it follows that in therr'esent oase plication there is inevitably some uid interif the liquid-in the bearing is allowed to become change between the cavities in which the bearstagnant-it'will become hot owing to shearing of ings are enclosed, on the one hand, and the the illm during operation, and the viscosity will cavities in the pump which are traversed by the pumped liquid. on the other hand, so that even though the bearing chambers 'may `be initially fined with clean liquid, this liquid is bound to become replaced i'n the course ot time by pumped liquid which in the case of water almost invarf lably contains solid matter in'suspension. 'I'hls circumstance is of little or no consequence if the pump is used for instance in water coming from chalky or clayey strata. However, in many cases', as for instance when the pump is to be used in water which contains destructive abrasive matter, it is desirable toprevent the'access ofthe surrounding liquid in its raw stateto the bearings, and more particularly to the bearings of the motor and the'main or 'bottom bearing ol the pump, and itis the purpose oi the present invention to achieve this result.

pump unit of theklnd described.. the upper motor bearing, the chamber containing the coupling between the motor and pump shafts, and the lower pump bearing, constitute a sealed water 'circulating system. Accordingly, means are provided to prevent the entry' of the pumped fluid 4 surrounding said bearing into said water chamber through the bearing, whereby said chamber and bearing constitute a sealed water circulating To this end, we may provide concentrically sheet metal bellows cax'ryingat"c'ix'ie end a carbon on the'pump spindle and rotating with it,'whlle the other end of the bellows is sealed against a flange on the bearing shell which in its turn is v.sealed inthe end of a chamber in the admission piece separating the pump from the motor. This form oi sealing is not novel, per se. Its use ,in

the normal manner would. however, prevent the.

movement or circulation of` cool liquid past the outside oi the bearing and through the bearing clearance. f

Such movement or circulation of relatively cool fall. Ii thiscondition is allowed to continue unmechanical losses of the motor will add to the i heating eiIect ofthe bearing losses.

- In order to overcome this diillculty, according to a further feature of the invention, the sealed chamber enclosing a pump bearing is in circu- 3 lating communication with an adjoining sealed cooling chamber containing means for setting up forced movement of the liquid enclosed therein.

Thebearing enclosing chamber thus constitutes .an annex of an externally cooled chamber, and

the circulation of liquid between these two chambers is utilised to induce a subsidiary lubricating ilow of liquid through the bearing clearance.

It will be understood thatl in order to achieve ,the desired sealed condition oi the motor it is 4 also necessary to seal the point of ingress oi' the leads to the motor housing, and conventional expediente may be employed for this purpose. `In the case oi the bottom pump bearing. when s the pump unit comprises a dual-purpose admise sion piece containing the aforesaid adjacent cool-- ing chamber with which the sealedbearing enclosing chamber communicates, thischamber ing heat exchange between the circulating liquid 5g and the wall of the cooling chamber swept by the sure generated by the motor rotor itself.` For this purpose the said annular space behind the bearing sleeve may be arranged to communicate with a passage leading from the cavity surrounding the top motor bearing, past the outer wall of the cooling chamber to the upper part of this chamber. I In this case the chamber enclosing the bottom pump bearing and the chamber enclosing the top motor bearing are both in communication with each other and with the cooling chamber situated between them, and all three chambers constitute a circulating system which is completely sealed ofi from the pumped liquid inwhich the unit is submerged.

Means have to be provided to allow for expansion and contraction of the enclosed liquid due to temperature changes, and for this purpose we provide a small ceramic nlter of sufcollar being located in the cavity or chamber of the socket 2 which also contains the coupling 3.

The bearing sleeve 6 is located in a bearing shell 1 mounted in and projecting from the end of the socket v2,'and the bearing shell 1 is surrounded and enclosed by a sheet metal bellows gasket 8 which is xed to the flange 9 on the bearing shell 'I at one end, and at the other end iiciently fine grain at a convenient point in an outer wall of the sealed system, through which a breathing interchange may take place between the enclosed body of liquid and the surrounding liquid.

In order to ensure satisfactory starting of the unit, it may be desirable to provide two such filters, one at 1the top and the other at the bottom of the sealed volume, so that as little air as possible may be trapped, or it may be preferred to provide filling plugs by which an initial filling of clean liquid may be inserted. In order that the invention may be clearly understood and readily carried intopractice, reference will now be had, by way of example only, to the accompanying drawings illustrating the invention, in Which- Figure l is a longitudinal section of a combined admission piece and connecting member for the motor and pump of a submersible pumping unit, disposed in a horizontal position, with the present invention applied thereto.

Figure 2 is a cross-section on the line II--II of Figure 1 vFigure is a fragmentary section of a modified construction corresponding to Figure 1.

Figure 4 illustrates a further modification of the construction shown in Figure 3.

Referring to Figures 1 and 2, the pump and motor are connected together by an admission piece I, having a cavity formed by a socket 2 which contains the coupling 3 for the pump and motor shafts 4 and 5 respectively, the cavity being maintained full of water which is kept in a state of turbulence and-circulation by the rotating coupling 3. As in the aforesaid construction the end of the socket 2 carries the pump bearing 3a, along which the water travels, for lubrication purposes, from the socket 2, but in the present case the bearing is enclosed in a sealed chamber which forms part of a closed water circulating system, including in the present case not only a chamber containing the pump bearing but also the chamber containing the top motor bearing.

The motor end of this pump construction illustrated in Figure 5.,'and asdisclosed specifically in my co-pending application Serial No. 441,843, filed of even date herewith, shows this motor bearingenclosed in a chamber 2a adjacent .the motor 2b, The shaft 5 extends through the end plate lha, and the thrust bearing 9a held by the locking collar 9b, said thrust bearing and is attached to an annular plate or ring Ill whose 'inner periphery is arcuately slotted and between the slots makes contact with the bearing sleeve l. The ring I0 carries on its outer surface a carbon ring II which is pressed by the resilience of the bellows 8 against an annular plate or fiange I2 mounted on and rotating with the shaft 4.

The flange `I2 is enclosed by a casing I3 attached to the inner wall of the admission piece I, and the mouth of the casing I3 is covered over by the sand bell I4 mounted on shaft il, which serves in the usual manner to prevent easy access of solid matter into the casing I3.

Through the bearing shell flange 9 are formed holes I5, and formed in Ithe bearing shell l are longitudinal bores I6 which provide communication between the interior cavity of socket 2 and the space -or cavity Il at the end of the bearing formed by the flange I2 and the carbon ring I I. Thearcuate slots along the inner periphery of ring Ill provide communication between the interior of the bellows B and the space I'l at the end of the bearing.

The lwater within the cavity of socket 2 is kept in a state of turbulence by the rotating coupling 3, and circulates through the cavity of socket 2 and the chamber at the top end of the motor as described in our co-pending application aforesaid.

The water in the socket 2 is induced to ow by the coupling 3 in the direction of the arrows shown in Figure 5, through the passages in the thrust bearing 9a, the end Wall Illa, around the motor bearing and into the chamber 2a, and thence through passages I9a, I9, I8, I5 into the bellows 8 and chamber l1, and then through passage I6 back to the water chamber 2a. Thus, the water in this `closed circuit effects cooling of the pump bearing and the motor bearing, the heat taken up being dissipated through the walls of the socket 2.

The passage I9 has an opening fitted with a ceramic filter 20 and also has a' filling plug aperture 2|, so that the water circulating system through the bellows 8 and bearing 5, l can be filled up when required, and is maintained quite independent of the liquid being pumped, which flows through the admission piece I over the outside of the socket 2 and absorbs heat transferred to the wall of the socket from the motor bearing and the end coils of the motor ,winding by the water contained in the socket and chamber 2a, Vas well as by conduction from carbon ring I I.

surface 'of'uie bearing sneu 1, may be spireuy grooved to facil-itate'the passage of lubricating water along the bearing,

In the modification illustrated by Figure 3.

which is intended for shafts of larger diameter than Figures 1 and 2in addition to the longitudinal bores I6 for supplying cooling water for the bearing shell 1 to the cavity I1 at the end of the bearing formedby flange I2 and carbon ring c I I, the bearing shell 1 also has other longitudi- 10 nal bores 24 providing communication between the cavity I1 andthe Aspace below the bearing communicating through port I8 with passages I9: Thus the water entering space I1, through bores I8, from socket 2, leaves space' I1 through 15 bores 24 and re-enters into circulation through y portion I8 and passage I8.

Whilst in the case of vFigure 1 water ows through the bellows 8, in they case of Figure 3 therel is no circulation of water through the -bellows 8 which will merely contain stagnant i water, the bellows 8 in this case serving solely as a resilient means for holding the annular plate I8 and carbon ring II up to the flange I2 so as to form the closed cavity I1 at the end of 25 the bearing. If, however, it is desired to have the return now of water through the bellows 8 `of Figure 3 instead of through the bores 24 in.

the bearing shell 1, the bores 24 may be replaced by short longitudinal bor'es communicating by .3c

radial bores with the interior of the bellows 8, the water passing out o! the bellows through a bore in flange 8 corresponding to the bore I5 of Figure l. I I

In both of the above constructions the bellows gasket 8 is accommodated in a cavity 28 of the admission piece I, formed at the end of socket 2, vwhich communicates through a port 21 with the passage within the admission piece I through which the pumped liquid is drawn into the pump', 40

so that thev bellows 8 itself is Water cooled, and

heat transferred to it by the water circulated through the bearing s, 1 is in tum transferred to and removed by the pumped liquid.

- Figure 4 illustrates a modified construction 45 which 'dispenses with the use of the'bellows \8. This construction is somewhat similar to that of Figure 3 inasmuch as the bearing shell has the same passages I8 and 25 for the flow and return of the water between the chamber con` 50 taining the coupling 8 and the cavity I1 at the end of the bearingshell 1. In this case, however, the cavity I1 is formed by a cap 28 forming an extension on the end of the bearing shell 1,

against which the carbon ringY II is pressed by a rubber washer 28, mounted in a cavity in the said bell I4 which surrounds and encloses the The rubber washer 28 is' an undersizefit on the sleeve 30,so that it becomes deformed into the cup shape shown and it may 6c be pressed against the carbon ring II by a spring 3| mounted behind it in the cavity of the said bell Il. The rim of said bell rotates in a recess in plate 8 2 surrounding the cap 28,

The water circulation is lthe same as in the case of Figure 3, the dierence betweenf'fthe two" constructions residing in the method vof forming' the sealedv cavity I1 at the end of the It win be understood that by; virtue of the 70 described arrangement the motor is entirely sealed from the pump, so that none of .the main pump'd liquid can nd it way into the interior v of the motor. Since the casing enclosing e motor bearings and bottom pump bearing is L u tir-ely sealed from the `surrounding -liquid auerifrom the nlter and the seal around the shaft, it is not necessary to provide additional sealing means -for the top and bottom motor bearings of the form provided, as herein described,for

the bottom pump bearing. A An analogous arrangement may be provided if desired for the top pump bearing, butthe provision of -such means in connection-with this bearing it less important than in connection withthe main or bottom bearing of the pump, While it is also more diilicult to provide the requisite cooling chamber and breathing iilter. For these reasons it will generally be preferable to allow the top pump bearing to be lubricated and cooled by liquid derived from the impelle As already mentioned, submersible pumps are in the great majority of cases used for pumping water. It will however be understood that the present invention is applicable to any submersible pump irrespective of the nature of the liquid lhandled, provided such liquid has stuilicient vispump unit from the top by the delivery con;

nection in a sealed vessel to which the liquid to be pumped is supplied, it being merely necessary' to ensure that the level of this liquid in the vessel is maintained above the level o f the pump take.

What I claim and desire to secure by Letters Patent is:

1. A submersible pumping unit of the kind described, comprising in combination a pump, pump and motor shafts, said unit including a water chamber containing a coupling'between the motor and pump shafts and communicating with a p'ump shaft bearing, wherein means are provided to prevent' the entry of the pumped iiuid surrounding'said bearing into said water chamber through the bearing, whereby said chamber and bearing constitute a sealed water circulating system in which the coupling induces a iiow ofthe water in the chamber, through the motor and pump shaft bearing.

2. A pumping unit according toclaim 1, where-` in one end of the pump bearing is enclosed inv a cavity which is sealed in regard to surrounding liquid, and the other end of the'bearing communicates with the chamber containing the coupling.

3. A pumping unit according to claim 1, wherein the pump shaft bearing' is surrounded by a shell and a bellows gasket connected at one end to said shell and at its other endcoacting with a friction ring sealing the water, chamberA against entry oi the pumped fluid into said chamber and wherein the cavity `at the end of the pump shaft bearing communicates with the coupling chamber not onlyl along the bearing clearance but also through 'longitudinal bores the bearing shell. i

4. A submersible pumping unit of 'uielass described, comprising in combination a puinp,

pump and motor shafts, and a water chamber 'V'pumpfshafts and communicating with a pump i shaftbearing, wherein-means are provided to vprevent the entry o'f the pumped fluid surrounding said bearing into said water chamber through the bearing, whereby said chamber and bearing constitute a sealed water circulating system, and wherein a wall of said water circulating system over which the pumped liquid passes contains a filter' to permit the breathing interchange of liquid through the lter.

5. A submersible pumping unit of the kind set forth, having a pump shaft, a bearing and shell Itherefor located in the path of the pumped liquid, including a chamber communicating with one end of the bearing, liquid circulating means in said chamber operated by the pump shaft, a

' closed cavity communicating with the other end of said bearing, new and return passages through the bearing shell providing communication be- 'tween said chamber and said cavity, an annular extension on the bearing shell surrounding the pump shaft, a vflanged member on said shaft,

y an annular carbon member bearing on said annular extension, a rubber sealing ring between said carbon ymember and said flanged member,l

,and a spring bearing between said flanged member and said rubber sealing ring to press it againstsaid carbon member.

6. In a submersible pumping unit, the combination of a motor and shaft therefor for pumping a fluid in which the unit is submerged, a motor shaft bearing, a pump shaft driven by the motor shaft and a bearing therefor spaced from the motor bearing, a chamber in which the motor bearing is located, a separate chamber in which the pump bearing is disposed, passages establishing communication between the chambers aforesaid, said chambers and passages containing a cooling liquid and constituting a sealed liquid vcirculating system, and motor-operated means between said chambers for inducing a closed circulation in said system around the said bearings to cool the same separately from the iiuid being pumped.

7. A submersible pumping unit as claimed in claim 6, wherein he motor-operated means constitutes the coupling between the motor and pump shafts.

8. A submersible pumping unit as claimed iny f claim 6; combined with means in the chamber containing the pump bearing for sealing said bearing from the fluid pumped, including liquid receiving passages permitting the cooling liquid to circulate in the closed system over and around the pump bearing4 and back to the motor bearing chamber. i

9. In a submersible pumping unit, the combination of a motor and shaft therefor, a motor shaft bearing, a pump shaft driven by the motor shaft anda bearing therefor spaced from the motor bearing, a chamber in which the motor bearing is located, and adjustable sealing member surrounding the pump bearing for sealing off said bearing from the fluid pumped and forming liquid receiving passages communicating with the motor bearing chamber, and motor-operated impeller means between the sealing member and last-named chamber for inducing flow of liquid from the motor bearing chamber through the pump bearing chamber, said circulation constituting a closed circulation system independent of the fluid pumped.

l10. A submersible pump as claimed in claim 9, wherein the adjustable sealing member -comprises a bellows surrounding the pump bearing in spaced relation thereto and holding the liquid in the closed system from escape from the pump bearing chamber along the pump shaft.

11. In a submersible pumping unit, the combination of a motor and shaft therefor, a motor shaft bearing, a pump shaft driven by the motor shaft and a bearing therefor spaced from the motor bearing, a chamber in which the motor bearing is located, a separate chamber in which the pump bearing is disposed, la third chamber intermediate the other two chambers, through all of which chambers a cooling liquid is adapted to circulate, and a coupling for the motor and pump shafts arranged in said third chamber to induce flow of the cooling liquid in a closed cycle through said chambers and about said bearings.

GILES P. HOWARD.