US2056553A - Pump - Google Patents

Description

Oct. 6, 1936. E. L. ABRAMSON 2,056,553v

PUMP

Filed June 11, 1954 4 Sheets-She et 1 INVENTOR E. L. Abramson ATTORNEYS Oct. 6, 1936. E. L. ABRAMSON PUMP Filed June 11, 1934 4 Sheets-Sheet 2 F1 4- INVENTOR E. L Abrarmsnn BY w ATTORNEYS E. L. ABRAMSO N PUMP Filed June 11, 1934 4 Sheets-Sheet 4 NW; \w M My 5 INVENTOR E.L.Abramson ATTORNEYS Patented Oct. 6, 1936 UNITED STATES PATENT OFFICE PUMP ration of Delaware Application June 11, 1934, Serial No. 729,982

4 Claims.

This invention relates to rotary pumps and more particularly to rotary pumps of the multistage type.

One of the objects of the present invention is to provide a new and improved multistage rotary pump in which the high pressure stage is intermediate the low pressure stages, so as to minimize the stufling box pressures.

Another object is to provide a multistage pump having peripheral inlets with suction passages at each side of each impeller in order to balance the pressures exerted against the impellers.

Another object is to provide a multistage rotary pump in which the maximum pressures in the final stage act in substantially direct opposition to the maximum pressures in the first and second stages to relieve the impeller shaft of excessive bending stresses.

Another object is to provide a multistage rotary pump in which the impeller shaft and several impellers may be assembled as a unit to the pump structure, whereby such assembly may be properly balanced prior to assembly to the pump casing.

A further object is to provide a multistage rotary pump of. such construction that different performance can be obtained by changing the internal parts only.

A further object is to provide a multiple stage rotary pump which may be easily assembled and disassembled.

With the above and other objects in view, the present invention consists of certain features of construction and combinations of parts to be hereinafter described with reference to the accompanying drawings, and then claimed.

In the drawings, which illustrate a suitable embodiment of the invention,

Figure 1 is a plan View of the complete pump;

Fig. 2 is a side elevation of the pump shown in Fig. 1;

Fig. 3 is an enlarged vertical section taken approximately on the line 3-3 of. Fig. 1;

Fig. 4 is a transverse section taken approximately on the line 44 of Fig. 3;

Fig. 5 is an enlarged horizontal section taken approximately on the line 5-5 of Fig. 3, the upper portion of the pump casing being removed;

Fig. 6 is a section taken approximately on the line 6--6 of Fig. 3;

Figs. 7, 8 and 9 are vertical sections taken approximately on the lines 1-1, 8-43, and 9-9, respectively, of Fig. 3; and

Fig. 10 is a section taken approximately on the line Ill-I0 of Fig. '7.

.mounted upon the impeller shaft I4.

Referring to the accompanying drawings, in which like numerals refer to like parts throughout the several views, the pump casing is preferably comprised of three parts, namely, a lower half I, an upper half 2, and an end portion 5 which closes in one end of the casing, the opposite end being closed in by radial portions 3 and 4 formed on the upper and lower casing halves 21 and l respectively. The casing halves I and 2 are securely bolted together along their sides and the closed ends by bolts 6 and the end portion 5 is formed with a flange I that securely fits within the halves l and 2, the end portion 5 being rigidly secured to the halves l and 2 by suitable bolts 8. Preferably a flexible sealing ring 9 of suitable compressible material is interposed between the end portion 5 and the casing halves l and 2.

The lower half I is provided with suitable legs or standards It] for supporting the pump structure. Atone end the standard l0 carries a projectingarm II which terminates in an annular journal box l3. The end portion 5 is also provided with a projecting arm H terminating in an annular journal box l3. The journal boxes l3 receive the bearings I3a which support the impeller shaft 14. The bearings l3a are preferably of an antifriction type securely held within the journal boxes l3 and the ends of the shaft are reduced in diameter to provide shoulders 15 which seat against the inner races of the bearings I3a.

Threaded annular rings l6 are mounted within the journal boxes l3 at each side of the bearings |3a and at one end of the shaft the rings iii are engaged with the outer race of the bearing I3a. to provide for endwise movement of the shaft and bearing assembly, so that endwise adjustment ofv the shaft 14 can be obtained.

The pump here shown is of the three-stage type and embodies three spaced rotors I'l each having a hub l8 slidably and non-rotatably A shaft sleeve I9 is interposed between each pair of impeller hubs IB and acts as a spacer for the impellers and also protects the shaft I4 from the liquid being pumped. A threaded shaft sleeve 20 is also disposed on the shaft at each end to abut the endmost impellers ll. The shaft is threaded adjacent the ends of the shaft sleeves 20 to receive annular locking nuts 2! which abut the shaft sleeves 20. Shaft sleeves 20 protect the shaft M from the liquid being pumped and from being cut or scored by the packing and can be quickly and inexpensively replaced when necessary. Suitable keys 23 are also provided to lock the impellers I! and sleeves against rotation on the shaft M.

The end portion 5 and the portions 3 and 4 are so arranged as to provide counterbored hubs 24 and 25 respectively which surround the sleeves 20, waterproof packing 26 being disposed within the counterbores and packing gland rings 21 being provided to hold the packing 26 within the counterbores. The rings 21 are held in position by means of eye bolts 21a which are carried by the end portions of the pump casing.

Each impeller I1 is provided with a plurality of radial buckets 28 at each side, which open laterally and radially outwardly, and these buckets lie within the three pressure building passageways 29, 30 and 3|, the numeral 29 indicating the first stage pressure building passageway, the numeral 3|] indicating the second stage pressure building passageway, and the numeral 3. indieating the third stage pressure building passageway.

These passageways are not formed in the casing proper but are provided in removable pump rings, there being four rings 32, 33, 34 and 35 mounted within the bore formed by the casing halves I and 2. The first stage passageway 29 is formed through mating portions of the rings 32 and 33. The third pressure building passageway 3| is formed by mating portions of the rings 33 and 34, and the second pressure building passageway is formed by mating portions of the rings 34 and 35. It will be noted that each ring is provided with a hub 36 against which the impeller has a running engagement, and a flange portion 31 which engages with the bore of the casing. Each pair of rings is also formed with stop portions 38 which abut each other and engage with the outer periphery of the impeller, the stop portions 38 having a portion 39 which extends across the passageway in running engagement with the sides of the impeller, so as to direct the flow of fluid through the outlet port 40.

The lower casing half I is provided with an inlet stub 4| and the upper casing half is provided with an outlet stub 42. Each of the pressure building passageways has a double suction inlet, there being an inlet port 43 at each side of the impeller, the ports 43 being in the flanges 31 of the pump rings. The inlet stub 4| is provided with an inlet passage 44 which is divided to provide two branches 44a which lead to the ports 43 of the first stage pressure building passageway 29 through passages 45 and 46, the passages 45 being provided by the casing half I and the flange 31 of pump ring 32 and the passage 46 being provided by the casing half I and the spaced flanges 3'! of the pump ring 33. The pressure building passageway 29 discharges into a passageway 41 formed in the casing halves which conducts the fluid being pumped as shown in Figs. 7, 8, and 9, to the opposite end of the pump where it divides and enters the inlet ports 43 of the second stage pressure building passageway 30 through passages 48 and 49. The passage 48 is formed in the pump ring 35 and the passage 49 is formed by the spaced flanges 31 of the pump ring 34.

The fluid being pumped discharges from the second stage passageway 30 through the outlet port 40 formed between the flanges 31 of the rings 34 and 35 into a passage 5| where it is conducted through spaced passages 52 and 53 to the third stage pressure building passageway 3| through the spaced inlet ports 43 thereof. The passage 52 is formed by the upper half 2 of the IS and 20 casing and the spaced flanges 3'! of the pump ring 34 and the passage 53 is formed by the casing half 2 and spaced flanges 31 of the ring 33. Inasmuch as the rings 33 and 34 are utilized for two sets of passages, the passages 46 and 53 of the ring 53 are separated by webs 54 formed in the ring outside the pressure building passageway, as shown in Fig. 6, and the passages 49 and 52 of the ring 34 are separated by similar webs. Webs 55 are provided in the ring 35 as shown in Fig. 4, for directing the flow of the fluid and similar webs are formed in the opposite end ring 32.

The rings 33 and 34, as shown in the drawings, are formed of two semi-circular parts which prior 3 to the assembly of the upper casing half 2 to the lower easing half I are bolted together by suitable cap screws 56. The outermost end rings 32 and 35 are of one-piece construction, but if desired they may be of two parts like the other rings.

With respect to the arrangement of the various stages, it is to be noted that the third or final stage is intermediate the first and second stages, and also that the inlets and outlets of the final stage are substantially opposite the inlets and outlets of the first and second stages so that the stufling boxes will be subjected to the lowest possible pressure and so that the point of maximum pressure of the final stage is in direct opposition to the points of maximum pressure in the first and second stages, with the result that the impeller shaft will be relieved of excessive pressures in one direction which tend to bend the same.

In order to relieve the packings 26 or stuffing boxes of high pressure due to leakage past the impellers, these stuffing boxes are in communication, by means of conduits 59, with the inlet passage of the inlet stub 4| so that the high pressure in the stuffing box will be reduced to the pressure in the inlet passage.

The pump described can be very easily and quickly assembled and disassembled and in the disassembly of the pump the covers |3b for the journal boxes are removed and the bolts for the end cover and for the casing halves are removed. The upper casing half may then be lifted from the lower casing half. The cap screws 56 which hold the split rings together are then taken out and the upper portions of the rings 33 and 34 removed. The entire impeller and shaft assembly may then be lifted from the lower casing half I and the end rings 32 and 35 removed. This provides a construction by means of which the shaft and impellers can be balanced prior to the assembly of the pump. Also, since the fluid pressure passageways are formed in the removable rings such rings may be easily replaced by new rings and impellers of the same capacity or of different capacities while using the same casing.

Although a single embodiment of the invention has been herein shown and described it will be understood that numerous details of the construction shown may be altered or omitted without departing from the spirit of this invention as defined in the following claims.

What I claim is:

1. In a multistage rotary pump, a casing having first, intermediate and third stage annular pressure building passageways, each having a pair of inlet passages and a peripheral outlet, the outlet being between said inlet passages, an impeller for each of said passageways, an impeller shaft extending through said casing for rotating said impellers, outlet and inlet stubs on said casing, a passage in said casing communicating with said inlet stub and the inlets of said first stage passageway, and a passage in said casing communicating with said outlet stub and the outlet of said third stage passageway, the outlet oi! said first stage passageway being in communication with the inlets of said intermediate stage passageway and the outlet of said intermediate stage passageway being in communication with said third stage passageway, said third stage passageway being disposed between said first and intermediate stage passageways, the outlets of said first and intermediate stage passageways being substantially radially opposite the outlet of said third stage passageway whereby the maximum transverse pressure on said shaft created by fluid being discharged from said third stage passageway is opposed by the maximum transverse pressures created by fluid being discharged from said first and intermediate stage passageways.

2. In a multistage rotary pump, a casing having first, intermediate and third stage annular pressure building passageways, each having a pcripheral outlet, an impeller for each of said passageways, an impeller shaft extending through said casing for rotating said impellers, outlet and inlet stubs on said casing, each of said passageways having a lateral inlet at each side of its impeller, the outlet of said first stage passageway being in communication with the inlets of said intermediate stage passageway and the outlet of said intermediate stage passageway being in communication with the inlets of said third stage passageway, a passage in said casing in communication withsaid outlet stub and with the outlet of the third stage passageway, and a. passage in said casing in communication with the inlets of said first stage passageway, said third stage passageway being disposed between the first and intermediate stage passageways, the outlets of said first and intermediate stage passageways being substantially radially opposite the outlet of said third stage passageway whereby the maximum transverse pressure on said shaft created by fluid being discharged from said third stage passageway is opposed by the maximum transverse pressures created by fluid being discharged from said first and intermediate stage passageways.

3. In a three stage rotary pump, a casing having a bore therein, means closing in the ends of said bore, a plurality of pump rings within said bore, each forming with the next adjacent ring an annular pressure building passageway,

the third stage passageway being intermediate the first and second stage passageways, an impeller for each of said passageways and an impeller shaft for rotating said impellers, each oi. said pressure building passages having two lateral inlet ports, one at each side of the impellers and formed in the adjacent rings. and a pcripheral outlet port, said casing having passages connecting the outlet ports of said first and second stage passageways with the inlet ports, respectively, of said second and third stage passageways, an outlet passage in communication with the outlet of said third stage passageway and an inlet passage in communication with the inlet ports of said first stage passageway, the outlet ports of said first and second stage passageways being substantially radially opposite the outlet port of saidthird stage passageway, whereby the maximum transverse pressure on said shaft created by fluid being discharged from said third stage passageway is opposed by the maximum transverse pressures created by fluid being discharged from said first and second stage passageways.

4. In a multistage rotary pump, a horizontally split casing having a bore therein and having inlet and outlet stubs, one end of said casing closing in one end of said'bore, an end cap for the opposite end of said bore, four annular rings within said bore, each ring forming with the next adjacent ring an annular pressure building passageway whereby to provide endmost passageways and an intermediate passageway, an impeller for each of said passageways having sealed running engagement with adjacent rings radially inwardly of the passageway, an impeller shaft for rotating said impellers, said impeller shaft having one end journalled in said end cap and its opposite end journalled in the opposite end of said casing, the rings which form the-axially innermost half of each endmost passageway, and which form said intermediate passageway being horizontally split whereby upon removal of said end cap the upper portion of said casing and the upper portions of said split rings, said impellers and shalt and the rings which form the axially outermost half of each endmost passageway may be removed as a unit from said casing, and a pair of inlet pas- ERNEST L. ABRAMSON.

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