US 2537084 A
Description (OCR text may contain errors)
Jan. 9, 1951 w. H. PFARRER FABRICATED CENTRIFUGAL PUMP 3 Sheets-Sheet 1 Filed Sept. 4, 1948 ATTORNEY5 Jan. 9, 1951 w. H. PFARRER FABRICATED CENTRIFUGAL PUMP 3 Sheets -Sheet' 2 Filed Sept. 4, 1948 INVENTOR BY WW ATTORNEYJ.
W. H. PFARRER FABRICATED CEN'I'RIFUGAL PUMP Jan. 9, 1951 3 Sheets-Sheet 5 Filed Sept. 4, 1948 i innlinn==s nNvEN-roR W BY *5? ATTORNEYS Patented Jan. 9, 1951 UNIT E D STATES PATENT O F Fl CE FABRICATED OENTRIFUGAL PUMP William H, Pfarrer, Baldwinsville, N. Y assig'nor" to MorrisMachine Works, Baldwinsville, N. Y.,. a; corporation of New York Application; September 4, 1948, Serial No. 47,932-
1 Claim. 1.
This invention relates toa' centrifugal pump and more particularly, to a pumpof this type which is constructed mainly of members which arefabricated of flat sheet or rolled metal and areconnectediwith one another" by, welding, such members being generally, known in the industry as Weldments.
Heretofore the main members of such pumps have-been made of cast metalwhich necessitated makingpatterns foruse'in producing the molds in which these members were cast, which operation involves considerableexpense: The'production of 'the" pumps in this manner. also requires considerable machining for the" purpose of fin ishing the parts before they can" be "used.
One of'the objectsof thisinvention' is toprovide-a centrifugal pump; the principal members of which are constructed from metal sheets or 'the like which have been rolled'and from which these'members-can he cut by means of a flame orthe like and'connected with each other partly by welding and partly by means of bolts or similar means, thereby enabling the pump tobe manufactured and assembled with a minimum of machining and a so permittingthe'several parts of the pump to be easily and conveniently assembled" and" d sassembled" forinspection, ad'- justment and repairing;
A. further object of this? invention" is" to so organize a pump 'of. this character that the interior of-the samemaybe readily provided with a protecting lining, such: as rubber, metal or thedike; foruse in pu-mping'liquidscontaining abrasives and also liquids: of -acorrosive charac-;- ter, some of. thesehning; members-also: serving as" gaskets forproducing leakfetight jointsbe tween the members of the pump-casing;
In the-accompanying drawings:
Fig. Lis aside elevat on? of a centrifugal pump embodying these improvements.
Fig; 2 is. an elevationof thesamei viewed from the front end thereof.
Fig.1 3 is a fragmentary vertical longitudinal section,. on an enlarged scale;..taken .on line'3-3, Fig. 2;
Figs; 4 anda5:areverticalicrossusections; on a reduced scale; taken on the correspondingly numbered-lines ofFig.. 3." 1 Fig; 6 is a horizontal section taken on'line.-6--6,- Fig. 4.
In-thefollowing: description similar characters .ofLreference indicate likepartsin the sev-. eral figures of; the drawings I The numeral l8 represents. thebase; of the mainframe J01": the;. pump which-may; be a of any 2i suitable constructionrand which is provided on the upper side of. its front and rear ends-with front and rear standards ll, [2. The tops of these standards are" provided; respectively, with frontand rear bearings l3, [4 in which is journaled a horizontallongitudinal driving'sh'aft l5 which forms part of the means foroperatin'g the pump; This shaft may be driven by. power derived from any suitable source.
In general the pump proper of this invention comprises a casing which contains a pressure chamber l 6' havingvthe form of a volute, an inlet eye I! arranged centrally on the front side of this chamber and axially in line with the driving shaft, andan outlet spout lilextending tangen tially from a peripheral part of the pressure chamber, and a rotary impeller or runner arranged within the pressurechamberand mounted on the-front end of the driving shait'and adapted to draw the fluid'to be pumped axially inward through the inlet eye lT'into the pressure cham her It, rotatethe'same circumferentially within the latter and then discharge it tangentially therefrom through the peripheral outlet l8. v
The main members which form the enclosure or housing of the ca'singinclude a circumferenti'al wall; a front transverse sidewall and'a rear transverse sidewall. The circumferential wall of the pressure chamber is preferably made from a bar or stripof weldable metal which is rolled. so thatit: is channel shape-or U-shape'in cross section" and bent so as to form a peripheral wall I 9 which isof'substantially"cylindrical shape but is open or'split'at'on'e part thereof and terminates at itsendson opposite sides ofithis split'in two tangentialwingszll; 21 which are spaced: apart transversely and formi twolongitudinal wall sections of the enclosure constituting the tubular outletspout I8 oithescasing, as shown iniFig'; 4. At its front'and'rear edges this periph eral wall of'the'pressurechamber is provided with outwardly projecting 'fianges 22; 23' and" at their front and rear edges the outlet'spout walls 20', 2 l are provided with outwardly projecting coupling fiangesizll; 2.5, respectively.
The front wall of the pump". casing comprises a flat main section zowhich is -g'enerallyfof disk formtand secured at itsedge to the front" coupling flange '22 of the peripheral wall of the :pres sure:- chamber and is'provi'dedat one part of its. peripheral edge with'a tangentiallcheek 21 of 'flat' form extending: across thespace between: the*outer: and inner wings or spout walls 20, 21 and secured to the frontflanges'fliof these wings. The'main dislr section :265of: the-front casingswall and its tangential cheek 21 are preferably formed integrally from a Single plate or sheet of weldable metal.
The edge of the front casing wall is detachably connected with the front coupling flanges 22 of the peripheral wall by means of bolts 28, and the opposite edges of the cheek 21 are likewise connected with the corresponding coupling flanges 24, 24 at the front edges of the longitudinal wings or walls 28, 2| of the discharge spout I8 by means of bolts 29.
Axially in line with the driving shaft the disk section 25 of the front casing wall is provided with an opening 30 in which the rear end of a metal tube 3| is secured by welding 32, this tube forming the main part of the eye or inlet I! through which the fluid to be pumped is conducted into the pressure chamber of the pump. At its front or outer end this metal inlet tube has secured to its periphery by welding 33 a coupling flange 34 of metal whereby the inlet tube of the casing is coupled with suitable piping through which the liquid to be pumped is supplied to the casing.
For the purpose of maintaining the front wall of the casing in a flat condition and preventing the same from being distorted by pressure within the casing, means are provided for strengthening the same, this being preferably accomplished by a plurality of radial stiffening or reinforcing ribs 35 which are secured to the outer side of the front casing wall 26 and to the adjacent external surfaces of the inlet tube 3| and its coupling flange 34 by means of welding. These stiffening ribs are also constructed of strips of flat metal which have been rolled and cut into the required shape.
The rear side wall of the casing of the pressure chamber and its discharge spout are also constructed from a single sheet of plate metal which has been rolled and cut into shape so as to form a main disk section 36 which is arranged transversely in rear of the peripheral wall IQ of the casing and a tangential cheek or section 3'! which extends transversely across the rear edges of the longitudinal walls or wings 20, 2i of the discharge spout !8. The driving shaft extends through the central part of this disk of the rear wall and is operatively connected at its front end with the impeller which is arranged within the pressure chamber of the casing. The edge of the disk of 'the rear wall is connected by bolts 38 with the rear coupling flange 23 on the peripheral wall of the casing and the transverse cheek 31 of this rear wall is also connected by means of bolts 39 with the flanges 25, 25 on the rear edges of the longitudinal walls or wings 20, 2! of the discharge spout or outlet, as shown in Figs. 2, 4 and 6. 1 The numeral 40 represents tie bolts passing through the edges of the disks 25, 36 of the front and 'rear' casing walls and the flanges 22, 23 of the peripheral or circumferential wall l9 of the case and having the heads and nuts at opposite ends of the bodies of these bolts bearing, respectively, against the outer sides of these walls for the purpose of tying the several walls of the casing firmly'together, as shown in Fig. 3.
In its central part the disk section of the rear casing wall is provided with an opening M in which is secured, by Welding 42, a tubular neck43 of weldable metal which is axially in line with the driving shaft and surrounds the adjacent portion of the same and forms partof the casing. .The numeral M represents an annular head secured at its periphery by welding 45 to the rear end f the casing neck 43 while its central part is provided with an opening 45! for the passage of the adjacent part of the driving shaft, as shown in Fig. 3. This casing head 44 together with the casing neck 43 form a recess or pocket 46 on the inner side of the rear casing wall which opens into the pressure chamber and is adapted to receive part of the hub 61 of the impeller.
On the outer side of the casing head a stuffing box is mounted which receives a packing and the adjacent part of the driving shaft and forms a joint therebetween for preventing leakage from the interior of the pressure chamber to the exterior of the same. This stuffing box, as best shown in Fig. 3, comprises a housing tube 41 of sheet metal surrounding the driving shaft and having its front end secured by welding 48 to the outer side of this head 44 and having its bore spaced from the periphery of the driving shaft so as to form an annular packing space therebetween, and an outwardly facing internal shoulder .9 on the outer side of the head 44, as shown in Fig. 3. The tube 41' is filledwithalubricating packing 5!! of any suitable character and this is pressed inwardly toward the shoulder 49 by a gland 5| projecting into this tube and held in place in any suitable manner.
Strengthening of the rear casingwall, for the purpose of preventing pressure within the chamber it from distorting this wall, is preferably accomplished by means of a plurality of stiffening or strengthening ribs 52 of flat metal arranged radially around the outer side of the rear casing wall 36 and secured by welding to the outer side of this rear wall and the adjacent part of the casing neck 43 and the casing head 44, as shown in Fig. 3.
Various means may be employed for mounting the casing of the pump on the main frame but those shown in the drawings are preferred and constructed as follows:
The numeral 53 represents a supporting ring of weldable metal which is arranged concentrically around the driving shaft and associated parts and is secured by welding 54 to the several ribs 52 of the rear casing wall plate. This supporting ring together with the pump casing is detachably connected with the main frame of the pump by engaging the lower edge portion of the supporting ring 53 with a semi-circular seat or shoulder 55 on theiront part of the main frame and detachably connecting this ring with the respective part of the main frame by a plurality of bolts 56, as shown in Figs. 1, 3 and 5. By these means the pump casing can be readily mounted on the main frame when originally installed and also quickly removed therefrom for inspection, adjustment and repairing whenever this is required. The supporting ring 53 is reinforced by stiffening ribs 51 of metal secured to the outer side of this ring by welding.
Means are provided which embody this invention whereby the tangential outlet or discharge spout [8 of the pressure chamber is connected with a delivery piping or conduit for carrying the liquid which has been pumped to the desired destination. The preferred means for this purpose which are shown in Figs. 1, 2 and 4 are constructed as follows:
The numeral 15 represents an annular coupling flange which has its inner side secured by Welding to the outer edges of the transverse walls 21, 3'! and the longitudinal walls 20, 21 of the delivery spout l8, this coupling ring being also connected :by welding tometai brackets 58 which are welded to the outer side of the transverse walls 21,31.
The numeral 59 represents an adaptor tube which may formzpart'of thepiping whereby the tube and the coupling flange l5whic-h is permanently connected with the discharge-spout.
- The impeller whereby-the'fluidto be pumped is drawn into the" casing through the inlet eyell of the same and discharged through-thetan- .gential outlet I8 thereof may be variously congstructed, that formshown in Figs. 2; 3=and 4 being constructed as follows:
The numeral 67 represents thehub of theimpeller which is'provided with a conical bore engaging with-the conical front end of. the" driving .shaft'and held thereon by aretaining nut 68 screwed onto the driving shaft and bearing against the inner end-of this hub-. From the'.
and rear shrouds.
' The numeral H represents a plurality of curved impeller vanes or blades which extend across the space'between'thefront'and rear shrouds and are preferably integrally connected therewith. As this impeller rotates in the direction of the arrow indicated in Fig. 4, the liquid in the pump isd'rawn through the inlet eye 11 into the space between the shrouds of the impeller and then this liquidis rotated inthe pressure chamber and discharged therefrom through the tangential outletthereofin a manner common to this type of pump.
In order to protect the internal surfaces or parts of the pump against wearand-corrosion when the same is utilized for pumping; liquids containing abrasive materials or chemicals which 'havea destructive effect on iron or'steel'; of which the main parts of the pump are constructed, the inner surfaces of the pump are provided with protective linings or coverings of-a character which will resist'wear or. corrosion dependingup'onthe character of the material which is being pumped.
The means for thus protecting the internal surfaces of the pump against wear or corrosion are constructed as follows:
The numeral 6! represents a protecting lining section having the form of a fiat disk which is secured to the inner side of the front casing wall 26 and provided centrally with a forwardly projecting protecting lining tube 62 which is arranged in the bore of the inlet tube 3! of the casing. At its periphery this lining disk BI is provided with a tangential protecting tab 63 which covers the inner side of the tangential cheek 21 forming the front wall of the discharge spout I8. The edges of the lining disk GI and the lining tab 63 are arranged between the flanges 22 and 24 on the front edges of the cylindrical casing wall It and its wings 20, 2| and these members are connected by bolts 28, 29, whereby these parts of the lining also form gaskets or packings and produce a tight joint between the respective parts of the casing.
The numeral 64 represents the fiat disk section '6 of a-iprotectingllming secured to the inneri'side of the rear casing 'wa1l'36and provided centrally withiarearwardlyprojecting tube 65 which'is arranged'iin' the bore of the tubular neck 43 soas to form aprotecting, lining therefor.
At one part of its peripheral'edge the rearlining disk" 64'is provided with a tangential tab 66 which extends across the flanges 25, 25 on the rear edges'cr the Wings 20; 2i of the discharge spout and form's'a protecting lining for the rear cheek 31 of the rear casingwall 36. The edge portions of the disk 64 and its tangential tab Stare arranged; respectively, between the flanges 23, 25 -011 the rearedges-of'the cylindrical wall section l-e and its wings 20, 2l'andthe edges of the rear wall disk 36 and its. cheek 3'! and clamped between the same by bolts 49, 39 so that the liningsections 64, 136 serveasa gasket between the respective parts of the pump casing whereby leakage from the interior of the pressure chamber-to the exterior of the pump is prevented.
The numeral 76 represents a protecting lining section having the form of a split cylinder and covering the inner side of theoylindrical peripheral 'wall I9 of the casing'and having its ends onopp'osite sidesof its splitpart provided with inner-and outertangential flaps .11, 18 which are arranged lengthwise and cover the inner sides of the longitudinal wings 20', 2| of the casing outletspout l8, as shown in Fig. 6; The cylindrical lining section IS-engages its front and rear edges withinner opposing sides of'the marginal parts of'the front and rear protecting disk lining-sections 61; 64, shown in Fig. 3, and the front and' rear edges ofthe innerand outer lining fiaps l'l, 18 0f this cylindrical lining-section engage Withthe vertical edge portions of the'fron't andrear lining tabs 63. 66 of the outlet'spout I8, as shownin Fig; 6.-
By these means virtually the entire inner surfaces of the casing are-covered with protecting material; I
When this pumpis used for propelling liquids of an abrasivecharacter these lining members are preferably constructed of rubber or similar resilient'material which iswear resistant and when rubberis used as a protecting lining these several members are connected with respective metal parts of the pump by vulcanization. When, however, this lining is composed of material which is intended to' render the internal surfaces of the'pump" corrosion resistant these protecting members may be constructed of lead or other metal or material best suited to the particular liquid which is being pumped. Metallic linings may be secured to the inner surfaces of the respective pump members by Welding or any other suitable method.
For the purpose of protecting the main surfaces of the impeller which come into immediate contact with the liquid which is being pumped and thereby save them from undue wear or corrosion the following means are provided:
The numeral 12 represents a protecting covering of rubber or equivalent material which completely covers or envelopes the opposite flat sides and edges of front shroud 10, as shown in Fig. 3.
Each of the impeller blades or vanes H is completely covered on its opposite curved sides and on its edges by a protection coverin 14 of rubber or the like, as shown in Figs. 3 and 4.
The rear shroud 69 of the impeller is protected by a covering of rubber or similar material which comprises an inner disk shaped lining section 13 secured to the inner side of the rear shroud and provided centrally with an opening 75 through which the front end of the drivingshaft projects, an outer disk shaped lining section 16 secured to the outer side of the rear shroud and connected at its peripheral edge with the corresponding edge of the inner lining section by a web 90 extending over the peripheral edge of the rear shroud, and a tubular collar 9| projecting rearwardly from the central part of the outer lining section 16 and secured to the periphery of the impeller hub 61.
At its front end the hub of the impeller is pro- 'vided with an annular shoulder or rabbet 92 and the peripheral part of this nut bears against the inner edge portion of the lining section- 13 around the central opening 15 thereof "and presses same firmly against the impeller hub, .as shown in Fig. 3. I I
As a whole the several parts of this pump are extremely light thereby permitting the same to be easily handled for transportation and for lining and relining. The interior of" the pump is readily accessible for lining or relining and also enables a beter and more reliable bond to be obtained between the lining sections and the :metal members of the pump to which they are :attached. Inasmuch as most of the several members of this pump are made of sheet metal, such as steel or an alloy, these members can be economically pie-fabricated by cutting or stamping, thereb eliminating the high costs attending the manufacture of pumps as heretofore constructed and also permitting of readily applying natural rubber or synthetic rubber to those surfaces which are engaged b the stream of liquid which is being pumped. Moreover, by making the main parts of this pump of sheetlike or rolled metal, comparatively smooth surfaces are presented on the inner side of the pump for attachment of the protecting linings thereto which can be accomplished more readily than attaching such linings to the rough surfaces of castings.
The use of sheet metal for making the major parts of this pump instead of using castings has the further advantage that it eliminates to a very large extent machine work which is required 8 when making parts of cast iron as has been the practice heretofore.
I claim as my invention:
A centrifugal pump comprising a casing containing a pressure chamber, an axial inlet on one side of said chamber and a tangential outlet on the periphery of said chamber, and an impeller rotatable in'said chamber; said casing including a split cylindrical section forming a peripheral wall of said pressure chamber and two wings at opposite ends of the cylindrical section and forming the longitudinal walls of said outlet, a front transverse wall plate having a front main disk section secured at its edge to the front edge of said cylindrical section and forming the front wall of the pressure chamber, and a tangential front cheek arranged on the edge of said front disk section and secured to the front edges of said wings and forming the front wall of said outlet, a rear transverse wall plate having a rear main disk section secured at its edge to the rear edge of said cylindrical section and forming the rear wall of the pressure chamber, a tangential rear cheek arranged on the edge of said rear disk and secured to the rear edges of said wings and forming the rear wall of said outlet, stiffening ribs secured to the outer side of said rear wall disk section, a main frame having a seat, and means for mounting said casing onsaid frame including a supporting ring secured permanently to said stiffening ribs 'and engaging said seat, and bolts detachably connecting said supporting ring with said frame.
' WILLIAM H. PFARRER.
REFERENCES CITED I The following references are of record in the file of this patent: