US1874324A - Centrifugal pump - Google Patents

Description

Aug. 30, 1932. J. w. MACMEEKEN CENTRIFUGAL PUMP Filed Sept. 29, 1927 4 Sheets-Sheet l JZWMAcMEEKEN.

l TOR ATTORNEY Aug. 30, 1932. J. w. MACMEEKEN CENTRIFUGAL PUMP Fil'ed Sept. 29 1927 4 Sheets-Sheet 4 ATTORNEY W JWMAQMIIREN.

Patented Aug. 30, 1932 UNITED STA-ms PATENWT OFFICE JOHN WEST IACHEEKEN, OI GLEN RIDGE, NEW JERSEY, ASS IGNOR TO WORTHINGTON PUMP 1ND MCHINEBY CORPORATION, OF NEW YORK, N'. Y., A CORPORATION OF VIRGINIA I OENTRIFUGAL rm Application fled September 29, 1027. Serial No. 222,757.

In centrifugal ump construction, a pump which must deliver a quantity of liquid against a specified head may be much simpler and' consequently less expensive to manufacture, if the speed of rotation can be made high enough to enable the generation of head to be accom lished in a single stage pump. When the ead delivered against by the pump is relatively high, high rotative speed of the impeller is required and at such speeds it is of great importance that alignment of the shaft and rotative elements be maintained true in the bearings, clearance rings of the impeller and in the stuffing box.

It is also of im ortance for hi h speeds that the pump sha t remain in a gnment with,

the shaft of the prime mover or driving motor when the latter is directly connected to the pump shaft.

Variations in tem eratur'e of the fluid pumped, especially w en very high temperatures are reached, will result in expansion or contraction of the pum parts, which would in ordinary approve constructions of centrifugal pumps, seriously affect the alignment of the rotative elements of the pump, and its operation, and it is an object of the present invention to provide a pump structure which will ensure proper alignment of the shaft and rotating elements during temperature variations from the lowest possible degree to the perature at which the liquid is to be pumped.

More specifically, the present invention comprises a centrifugal pump, constructed and designed throng mum dissipation of heat and minimum transferring "of heat, from the liquid being pumped, to the bearings and bearing suports and also embodies provision for coolmg the bearings and permitting only movement of the pump casing axially or parallel to the shaft, thereby preventin misalignment of the bearings, pump sha and shaft highest operating temout to permit maxi-- P advantages and dangers of'impairment of operation of the pump.

Another object of the invention is to pro.

vide a centrifugal pum for pumping hot liquids in which the num er of joints in contact with high temperature liquid are reduced -to a minimum, thereby reducing dangers contingent with leaka e of fluid being pumped and one in which the one joint, necessary for assembly of the pum so subject-1 ed is located, where there is no ifierences in temperature at its sides.

In the preferred form of the invention, the above objectsare attained by rotating the shaft in bearinfgs which are centred in a cool pedestal or ,rame, unaffected, or affected only to a slight degree, by the heatof the fluid, and the pump casing, due to the fact that the frame or pedestal has an air cooled joint and the minimum necessary contact with the pump casing, therefore only the minimum passage of heat from the casing to the frame will take place. The joint between the pump casing and the frame vor pedestal is also so designed that radial movement under heat expansion may be prevented and only axial movement, or movement sistance to expansion or contraction of the casing, under temperature variances, in an axial direction, they resist any transverse movement from strains in external plpmg and resist any turning movement which might result fromstrains from the discharge ipe.

With these objects in view, the invention consists in various features of'oonstruction and combination of parts, which will be first described in connection with the accompany- ,ing drawings, showing a centrifugal pump of the preferred form embodying the invention, and the features forming the invention will be specifically pointed out in the claims.

in the drawings Figure 1 is a side elevation of the improved pump showing it coupled to a motor which serves as prime mover for the pump.

Figure 2 is an end elevation of the pump.

Figure 3 is a longitudinal section through the pump.

Figure 4 is a cross section through the pump, taken on the line 44 of Figure 3.

Figure 5 is a top plan of the base plate of the pump.

Figure 6 is an enlarged view, partly-in section, showing the connection of the pump casing with the base plate. igure 7 is a longitudinal section through a modified form of the pump.

' Referring more particularly to the drawings, the improved pump which is shown in rawings is a single stage or single imller centrifugal pump, primarily designed or the pumping of hot fluids such as petroleum oil during its circulation through a refinery and includes the pump casing 1 which is formed of the suction or inlet section 2 and what is herein called thebearing section 3. Thesections 2 and 3 of the pump casing are I constructed so as to facilitate assembly of the pump and.the proper mounting of the imller 4 in the casing and on the impeller driving shaft 5. The sections 2 and 3 are connected in approved manner, such as by bolts 6 and their point of contact as indicated at 7 provides the only pressure joint in the entire pump construction. The suction or inlet to the pump impeller is axial, through the inlet 8, while the discharge from the pump is through the volute or difl'user 9 and discharge outlet 10, such construction being usual in centrifugal pumps. The usual impeller rings 11 are emplo ed in the pump structure and any approve means, be provided for connecting the impeller 4 to the shaft 5. In maintaining pro er perform- *metal to metal joint 21 with the section 3 of xtilglpump casing. The joint 21 is preferably ance of a centrifugal pump oft vitally necessary that the shaft 5 and impeller 4 remain in alignment, that the impeller remain in tive to the impeller rings 11 and also that'the shaft shaft 14 of the prime mover15 when the pump.

shaft Sis directly coupled to the shaft 111 as shown in Figurel of the drawings." To accomplish the above, the shaft 5 rotates in bearings .17 which arecentred in a cool pedestal 18. The

ed surfaces 19 on the bed plate 20 edthe pump structure-and has a rabbeted ed, at circumferentially spaced'points as shown at 22 and it is so designed as to provide minimum contact between t e pedestal 18 and the section 3 of the pump casing 1, thereby per;- mitting very-little transmission of heat from the casmg 1 tothe pedestal 18. The pedestal as indicated at12, may

s type, it is proper alignment and position r ela-' samelpressure as the suction of the 1" 5 remain in proper. alignment with the construction and directional flow of the cool pedestal 18 is supported upon suitculation of air between the flange 26 and the impeller enclosing part of the section 3 to allow cooling of the flange and dissipation of heat; the entire construction being designed so as to permit the maximum dissipation of heat from the flange 26 and the minimum transfer 7 of heat to the pedestal 18, so as to render the bearings unaflected in alignment by temdperature variations in the casing 1. The pe estal 18 is provided with a pluralit of air openings 28 which permit free circu ation of air to facilitate the removal of any heat which might travel along the casing and casing extension 29 into the interior of the pedestal 18.

Cooling of the bearings 17 is accomplished by the admittance of cool oil undefa pressure greater than the suction pressure of the pump to the interior of the casing extension 29 through the pipe 30. The cool oil travels along the groove 31 in the forward bearing 17 towardthe impeller 4;, lubricating the hearing and passing into the balancing chamber 32 .of the pump, from whichit passes out through the vent 1pc 33. This eakage of cooloil through t e groove 31 c ls the shaft 5 and reduces the temperature in the balancing chamber 32, providing achamber of intermediate temperature betw'een the hot and cold' elements of thepulup out through 'the pi pipe'33 is connecte or will be hydraulically balanced. This oil permits the placing of a bearing close to the impeller, thus reducing the reaction of the load on' the! bearing in accordance with the best practice. This is possible with the direction of flow of cool oil without resulting in too pump, the.

Her 4 cannot becomevapor bound Any leakage through the high a temEerature in thebearing; however,

without an cient flow of cool oil towards the impeller, the oil in the bearing would be in dan r of losingits physical and chemical qua ties due to decomposition under temperature for a duration of time.

0001 oil also travels through the roove 34 formed in the outer bearing 17 an throu h the 'stufling box 35 where itlubricates the packing 36 in the stufiing box, thereby sealshaft and packin 36.

From the foregom description, taken in connection with the rawin it will be apparent that: by the extending of the pump casing 1 in the dish shaped flange 26 continuous with the curvature of the casing 1 :the rabbeted. metal to metal joint21 between the pedestal 18 and easing 1, to ether with the. drilled openlngs 22 therein, w "ch provide the minimum necessary contact between the casing and pedestal, as well as the spacing of the flanges 24 and 26 to rmit circulation of air about the coupling olts 25: the( maximum dissipation of heat with the minimum passage of heat from the pump casing 1 to the pedestal 18, which holds the alignment .of the bearin s, will be provided.

n addition to the above features and the cooling of the bearings 17 by cool oil, the free circulation of air within the pedestal 18, which is provided by means of openings 28, will convey away such heat as may pass to the inside of the pedestal, so that the alignment of the bearings and the pedestal will remain unaffected by temperature changes of the casing 1 and of the fluid being pum ed, thereby preventing misalignment-of the s aft 5 and lmpeller 4. It will be noted by reference to the drawings that the oil introduced for cooling the bearing surfaces does not mix with the oil or fluid passin throu h the pump and therefore has no a verse e ect on i the process of refining the oil being pumped and does not affect the temperature of oil delivered by the pump.

The casing 1 o the pump will however be subjected to expansion and contraction under tem erature variations and the entire design of the pump, including the provision of'the and contraction axially or in a direction parallel to the shaft 5 and a construction is embodied in the pump structure which will offer no appreciab e resistance to expansion or contraction of the casing in an axial direc-- tion, but will resist any transverse movement of the casing from strains in the external pipe which is connected to the pump, or from any other source, and resist any turning movement which might result from strains from the discharge pipe. cludes a depending lug 40 formed on the under side of the casing 1. The lug 40 has a groove 41 cut therein, which extends parallel to the shaft 5 and slidably receives a key ,42.

a The key 42 fits in a groove 43 formed in the upstanding boss 44 and it is attached to the boss carrying member 45 in any suitable manner, such as by a'cap screw 46. The member 45 in turn rests upon a finished surface bu the bed plate 20. The bed plate 20 has upstanding pedestals 47 thereon upon which suitablesupporting lugs 48 formed on the pump This construction in casing 1 rest. The slidable supporting connection formed between the ump casing sec the shaft but will resist or prevent movement of the casing transversely of the shaft, thereby, with the other features previously described, providing maintenance of proper alignment of the rotative parts of the pump with their respective companion stationary parts, and eflicient, pro er operation of the pump will be permitte under any and all temperatures to which the pump is subjected and under the variations of such temperatures,

. In Fig. 7 of the drawin a modified form of the improved pump is s own, which ump is similar in'many'respects to the pre erred form illustrated in Figs. 1 to 6 inclusive. However, the construction shown in 7 is applicable for pumps of smaller size and capacity than the type shown in Figs. 1 to 6.

In the modified form of the invention, the shaft 50 which carries the" impeller 51 is mounted in a single bearin 52 which is carried by the sleeve 53 forme on the section 54 of the pump casing 55 and the bearing 52 and sleeve 53 are centred in the cold or cool pedestal 56, which corresponds to the pedes- As in the preferred form of the invention, a

cooling oil sup 1y pipe 57 ,passes through the sleeve 53 and elivers cooling lubricating oil to a groove 58 in the bearing 52 and said oil passes along the shaft 50 towards the impeller 51, into the balancing chamber 59 from which it is carried off by the vent pipe 60. The pedestal 56 is mounted upon a suitable supporting base in the same manner in which the pedestal 18 is mounted and' it has air circulating openings 61, to ermit circulation of air in the pedestal, and a out parts of the section 54 of the casing 55 for dissipating the heat.

The pump casing 55 is formed of the sections 54 and62 which are connected by a pressurejoint 63, the said joint being the only pressure joint in the pump structure. The section 54 has formed thereon the connecting flange 64 which is dish shaped and continues in the curvature of the casing 55 for providing maximum circulation 0 air about the flange 64 and expansion and oontraction of the casing, due to temperature variances, ina bellows-likemanner. The flan e 64 is connected by rabbeted joint 65 and be is 66 with the flange 67 on the pedestal 56. The

flanges 64 and 67 are-spaced so as to rmit circulation of air about the bolts 66. n fact,

the modified form of the pump is similar in construction and operation to the preferred form in all respects with the exception that Aim - a shaft for rotating the forms of pum s, a ball bearing structure of approved arm is illustrated, which is a bearing capable of both radial and axial load.

hese, or equivalent bearings make the pump a self-contained machine, which may be coupled by means of the coupling 71 direct to a standard commercial motor as shown at 15, or other suitable prime mover.

It will also be apparent that by the maintaining of proper alignment of the rotary parts of the pump with'the stationary parts of the pump, proper alignment between the shafts 5 and 14 will also be maintained, and while the prime-mover 15 is shown as an electric motor, it is to be understood that any suitable type of prime mover may be employed without departing from the spirit of this invention.

It will be understood that the invention is not to be limited to the specific construction or arrangement of parts shown but that these may be modified widely within'the invention defined by the claims. u

What-is claimed is: 1. In a centrifugal pump for'pumping hot liquids, a pump casing, an-impeller therein, a shaft for rotating the impeller, a supporting pedestal said casing having a dish shaped connecting flange continuous with the curvature of the casing, ed connection to the pedestal to permit air cooling of the flange and boltconnection for the dissipation of heat.

2. In a centrifugal pump for pumping hot liquids, a pump casing, an impeller therein, a shaft for rotatin the impeller, a supporting pedestal, sai I casing having a dish shaped connecting flange continuous with the curvature of the casing, and ha spaced, bolted connection to the pedestal to permit air cooling of the flange and bolt connection for the dissipation of heat, sald flange having a relatively small metal to metal contact with the pedestal to reduce to a minimum transmission of heat from the casing to the pedestal.

3. In a centrifugal pump for pumping hot liquids, a pump-casing, an impeller therein, a shaft for rotating the impel er, a supporting pedestal, said casing having a dish shaped connecting flange continuous with the curvature of the casing and having spaced, bolted connection to the pedestal to permit air cooling'of the flange and bolt connection for the dissipation of heat, and having a relatively small rabbeted metalfto metal contact with the pedestal, said rabbet-.

ed contacting parts being drilled at circumferentially spaced points ,to reduce to a minimum the contact between the casing and pedestal.

4. In a centrifugal pump for pumping hot liquids, a pump casing, animpeller therein, impeller, a supporting pedestal, said casing having a and having spaced, bo1t-,

ternally by the its axis will be coincident both with the axis.

shaped connecting flange continuous with the curvature of the casing and having spaced, bolted connection to the pedestal to permit air cooling of the flange and bolt connection for the dissipation of heat, bearings for the shaft centred in said pedestal, said bearing adapted to receive cooling fluid under pressure for cooling said bearings, whereby theshaft and impeller will remain in alignment during temperature variations of the casing.

' 5. In a centrifugal pump for pumping hot liquids, a casing, an impeller therein, a shaft for rotating the impeller, a prime mover including a shaft direct coupled to the pump shaft, a supporting pedestal, said casing hav ing a dished connecting flange continuous with the curvature of the casing, a flange on the pedestal and disposed in spaced relation to said dished connecting flange and bolted thereto for connecting the casing and pedestal to permit air cooling of the flanges for dissipation of heat, said casing and pedestal having relatively small metal to metal contact, whereby transmission of heat from the casing to the pedestal will be reduced to a minimum to permit maintaining of alignment of the impeller, pump shaft and prime mover shaft.

6. In a pump for pumping hot liquids, a pump casing, an impeller, a shaft-for rotatmg the'impeller, a supporting pedestal, said casing having a dish shaped connecting flange continuous with the curvature of the casing and having spaced, bolted connection to the pedestal to permit air cooling of the flange and bolt connection, a balancing chamber in said casing,-a bearing'for the shaft centred in said pedestal, said bearing arranged to ermit circulation of cooling liquid about an through the bearing shaft into said balancing chamber.

7. In a centrifugal pump for pumping hot liquids, an impeller, a driving shaft, a casing having only one joint subjected to pressure of fluid pumped, said casing having a vented balancin chamber thercim said casing extending yond the balancing chamber, both radially in a dish shaped, air cooled flange and axially in the form of a shaft surrounding sleeve, said sleeve'being spaced from the shaft, a bushing in the space between said sleeve and shaft, a stufling box at the outer end of the sleeve, a supporting pedestal provided with air circulating openings, said sleeve being centred in said pedestal and cooled external? by air circulation and inow of cooling fluid,'whereby of the pump shaft and with the axis of the prime mover shaft irrespective of the temperature of the fluid pumped.

along the 8. In a centrifugalpump for pumping hot liquids, a prime mover shaft, an impeller, a pump shaft, .a casing'h'aving a shaft-surrounding bearing-retaining sleeve formed thereon, a supporting pedestal provided with air circulating openings, said sleeve being central in said edestal and cooled externally by air circulation and internally by the flow of cooling fluid, whereby its axis will be coincident both with the axis of the pump shaft and with the axis of the prime mover shaft irrespective of the temperature of the fluid pumped.

9. In a centrifugal pump for pumping hot liquids, an impeller, a pump shaft, a drlving shaft, a casin having a vented balancing chamber therein, said casing extending be- 5 yond the balancing chamber axially in the form of a shaft-surrounding bearing-retaining sleeve, a supporting pedestal, said sleeve being central in said pedestal and cooled externally by air circulation and internally by the flow of cooling fluid, wherebyit axis will be coincident both with the axis of the pump shaft and with the axis of the driving shaft irrespective of the temperature of the fluid pumped.

10. In a centrifugal pump for pumping hot liquids, a pump casing, an impeller within the casing, a shaft for said impeller, a bearing for the shaft, said pump casing having a balancing chamber therein sealed from the fluid channel of the pump casing, said bearing arranged to permit circulation of cooled oil about and through, the bearin along the shaft towards said impeller an into said balancing chamber.

a5 11. In a centrifugal pump for pumping hot liquids, a pump casing, an impeller rotatable therein, a shaft for the impeller, a bearing'for the shaft, said casing having a balancing chamber therein sealed from-the 4o fluid channel of the pump casing, said hearing arranged to permit circulation of cool oil, about and through the bearing along the shaft and into said balancing chamber, and a an outlet from said balancing chamber for the oil passing thereinto, whereby cooling and lubricating oil will be circulated in the bearing and balancing chamber. without entering the fluid passage of the casing.

In testimony whereof I ai'fix my signature.

JOHN W. MACMEEKEN.

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