CA1135994A - Self-priming centrifugal pump - Google Patents
Self-priming centrifugal pumpInfo
- Publication number
- CA1135994A CA1135994A CA000318584A CA318584A CA1135994A CA 1135994 A CA1135994 A CA 1135994A CA 000318584 A CA000318584 A CA 000318584A CA 318584 A CA318584 A CA 318584A CA 1135994 A CA1135994 A CA 1135994A
- Authority
- CA
- Canada
- Prior art keywords
- section
- priming
- region
- pump
- centrifugal pump
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D9/00—Priming; Preventing vapour lock
- F04D9/04—Priming; Preventing vapour lock using priming pumps; using booster pumps to prevent vapour-lock
- F04D9/041—Priming; Preventing vapour lock using priming pumps; using booster pumps to prevent vapour-lock the priming pump having evacuating action
Abstract
Abstract of the Disclosure A self-priming centrifugal pump comprises an impeller mounted on a shaft and forming part of a main pump section, and a priming rotor operating in the manner of a side channel of liquid-ring pump mounted rigidly on the same shaft and operating and forming part of a priming section. A suction side of the priming section communicates through a first permanently-open passageway with a first region on a suction side of the main pump section where gas to be drawn off collects. The suction side of the priming section also communicates through a second permanently-open passageway with a second region of the main pump section which, during normal operation, is at a higher pressure than the first region. Both the first and second passageways are so designed that in normal operation a stream of liquid sufficient to coo] the priming section flows from the second region pump to the suction side of the priming section and from there to the first region.
Description
~35~9~L
The inven-tion relates to a self-priming cen-trifuya:l pump comprising an impeller forming part oE a main pump sec-tion, and a rotor forming part of a priming section, which is fixed to the ; same shaft and operates in the manner of a side channel or a liquid-ring pump.
In known pumps, the priming section is so arranged .. ~
; that even during normal operation of the pump, when no gas delivery is necessary, liquid flows through it. In some pumps, the flow of liquid through the pr:iming section that discharges to the atmosphere is shut off on its pressure side by a float valve as soon as the delivery of gas is finished. In other ; known pumps the flow path through the priming section that discharges into the pressure connector of the pump is closed by a non-return valve in the pressure side of the priming section if there is a danger that the priming section will be back-loaded during normal operation because of the greater pressure head of the main pump section., In both cases delivery through the priming section is necessarily shut off during normal opera-tion, so that the friction which occurs in the priming section because of its constant motion results in an increase in temper-ature. When a temperature close to -the boiling point of the ; liquid is reached, the priming section becomes inoperative.
The same result can occur, without any forced shut-off of the ~ flow path of the priming pump, if the pressure head of the I main pump section coincides with the maximum pressure head of the priming section. The delivery flow of the priming section is .
then shut off by back pressure.
~: :
Thus this invention provides adequate cooling for the ' priming section, even if the delivery flow through the priming section is shut off either fortuitously or of necessi-ty during normal operation of the pump.
~ccording to the present invention there is provided . -- 1 --, ~
,~ .
` ~359~34 a self priming centrlfugal pump comprising an impeller mounted on a shaf-t and forming par-t of a maln pump section, a primincJ
rotor of a side channel or liquid-ring pump mounted rigidly on the same shaft and forming part oE a priming section, a suc-tion side of the prlming section communicating through a firs-t per-manently-open passageway with a first region on a suction side of the main pump sectlon where gas to be drawn off collects, the suction side of the priming section also communicating through a second permanently-open passageway with a second region of the main pump section which, during normal operation, ls at a higher pressure than the first region, both the flrst and second passageways being so designed that in normal operation a stream of liquid sufficient to cool the priming section flows from the second region to the suction side of the priming section and from there to the first region.
. ~
r~, Unlike priming sections that are situated in the main ~ delivery stream of the pump, or are constantly involved in the .i delivery stream, in the case of this invention the cooling flow , does not pass through the priming section itself. On the con-trary, the cooling current flows past to the priming section through the two passageways, thereby removing heat.
A further difference from conventional pumps lies in the fact that during normal operation the cooling current flows ~` in the reverse direction through the first passageway, which during the priming phase carries gas from the suction side of the main pump section to the suction side of the priming section.
When several main pump stages are available it is always the last stage which is meant when reference is made to the main pump section in the foregoing.
Extremely efficient cooling of the priming section is achieved if the first and second passageways are connected to ; each other in the immediate vicinity of the suction port of the 13~35~9~L
priming section, so -that -the cooling current flows past -the suction por-t. This results in good fluid exchang~ -through the suction port of the priming section. In additi,on to, or instead of this, it can also be that the walls of -the first and/or of the second port are arranged in close, thermally conductive connection with the priming section. This means that even during normal operation the ~temperature of the priming section remains at a suitably low level so that it remains con-stantly operable and can immediately function once again as a priming section in -the event of aeration occuring on the suction side of the main pump.
It is desirable that a space axially adjacent to the impeller of the main pump section and connected on its pressure side be selected as the region from which the second passageway leads to the suction side of the priming section. However, it is not essential that this space be at the full pressure of the pressure side of the pump section providing it is sufficient-ly high to produce the desired cooling current.
I't is desirable that a chamber that is axially adjacent to the impeller and connected to the suction side hub region of the impeller be selected as the aforementioned first region.
This region is usually separated from the pressure side of the rotor by a sealing ring slot and is connected to the suction side hub area of the impeller through bores. This selection of the first and second regions is accompanied by the advantage of short passageway to the priming section. This selection of ~, I the regions thereby permits a short and direct connection to the suction side of the pump, where gases which are to be removed collect, and to the pressure side of the impeller. Finally, '~ 30 this selection of the aforementioned regions makes it possible to satisfy the requirement that the passageways discharge into , regions that are at different pressures, so as to ensure the ~' ~L135~
creation of a cooling current -through the aforementloned passaye-ways during normal operation of -the pump.
The invention is independent of whether or not the priming section has a suction chamber that is large in compari-son with the cross section of the passageways. If s~ch a suc-tion port is provided it is desirable that its axial extent be kept small, which is to say, not much greater than the half width of the impeller of the priming section in order that, on the one hand, fluid that is drawn from the main pump section during the priming phase enters the priming section quickly and as completely as possible, and, on the other hand, in order that during normal operation, i.e., during the delivery of liquid, the liquid that flows through the suction chamber passes as directly as possible to the suction side control plate of !
; the priming section. The suction chamber may extend a consid-erable amount in the radial direction for the purpose of pro-~;
viding large-area heat exchange.
It is desirable that a channel be provided which extends from a low region of the main pump section in order that when the priming phase begins, the liquid remaining in the pump is passed to the priming section as operating liquid. How-ever, even in the priming phase itself, considerable pressure can occur at the low point which accordingly is also at a con- ;
siderable distance off the axis. In order that this does not lead to overfilling of the priming section, to which the liquid is passed through the same port as the gas, it is frequently desirable to design the channel with a cross section that will restrict the passage of liquid to the priming section. This also restricts the strength of the cooling stream during normal operation of the pump. In addition, it can lead to the fact that if the first passageway is wide the pressure at the suction opening of the priming section may be very low during normal . , ~L~L3S~
:
opera-tion, an~ thereby promote cavitation. rrhis disadvanta(l~?
can be eliminated if the second passageway, in addition to the channel, also has an opening that discharyes in the main pump section next to the impeller and closer to the shaft than the . channel, that is to say, in a reyion where, because of greater - proximity to the axis, in the priming phase there is yas and not liquid. The passage of liquid to the priming section will :. thereby be restricted, on the one hand, whereas on the other, during normal operation there will be an adequate flow of cool-ing liquid as well as an increase in pressure at -the suction ; port of the priming stage.
The invention will now be described in more detail, ~ by way of example only, with reference to the accompanying draw-.. ings, in which the single Figure is a vertical cross section . through one embodiment of a pump according to the invention.
. The centrifugal pump housing 1 has a suction inlet ,.,~, .
The inven-tion relates to a self-priming cen-trifuya:l pump comprising an impeller forming part oE a main pump sec-tion, and a rotor forming part of a priming section, which is fixed to the ; same shaft and operates in the manner of a side channel or a liquid-ring pump.
In known pumps, the priming section is so arranged .. ~
; that even during normal operation of the pump, when no gas delivery is necessary, liquid flows through it. In some pumps, the flow of liquid through the pr:iming section that discharges to the atmosphere is shut off on its pressure side by a float valve as soon as the delivery of gas is finished. In other ; known pumps the flow path through the priming section that discharges into the pressure connector of the pump is closed by a non-return valve in the pressure side of the priming section if there is a danger that the priming section will be back-loaded during normal operation because of the greater pressure head of the main pump section., In both cases delivery through the priming section is necessarily shut off during normal opera-tion, so that the friction which occurs in the priming section because of its constant motion results in an increase in temper-ature. When a temperature close to -the boiling point of the ; liquid is reached, the priming section becomes inoperative.
The same result can occur, without any forced shut-off of the ~ flow path of the priming pump, if the pressure head of the I main pump section coincides with the maximum pressure head of the priming section. The delivery flow of the priming section is .
then shut off by back pressure.
~: :
Thus this invention provides adequate cooling for the ' priming section, even if the delivery flow through the priming section is shut off either fortuitously or of necessi-ty during normal operation of the pump.
~ccording to the present invention there is provided . -- 1 --, ~
,~ .
` ~359~34 a self priming centrlfugal pump comprising an impeller mounted on a shaf-t and forming par-t of a maln pump section, a primincJ
rotor of a side channel or liquid-ring pump mounted rigidly on the same shaft and forming part oE a priming section, a suc-tion side of the prlming section communicating through a firs-t per-manently-open passageway with a first region on a suction side of the main pump sectlon where gas to be drawn off collects, the suction side of the priming section also communicating through a second permanently-open passageway with a second region of the main pump section which, during normal operation, ls at a higher pressure than the first region, both the flrst and second passageways being so designed that in normal operation a stream of liquid sufficient to cool the priming section flows from the second region to the suction side of the priming section and from there to the first region.
. ~
r~, Unlike priming sections that are situated in the main ~ delivery stream of the pump, or are constantly involved in the .i delivery stream, in the case of this invention the cooling flow , does not pass through the priming section itself. On the con-trary, the cooling current flows past to the priming section through the two passageways, thereby removing heat.
A further difference from conventional pumps lies in the fact that during normal operation the cooling current flows ~` in the reverse direction through the first passageway, which during the priming phase carries gas from the suction side of the main pump section to the suction side of the priming section.
When several main pump stages are available it is always the last stage which is meant when reference is made to the main pump section in the foregoing.
Extremely efficient cooling of the priming section is achieved if the first and second passageways are connected to ; each other in the immediate vicinity of the suction port of the 13~35~9~L
priming section, so -that -the cooling current flows past -the suction por-t. This results in good fluid exchang~ -through the suction port of the priming section. In additi,on to, or instead of this, it can also be that the walls of -the first and/or of the second port are arranged in close, thermally conductive connection with the priming section. This means that even during normal operation the ~temperature of the priming section remains at a suitably low level so that it remains con-stantly operable and can immediately function once again as a priming section in -the event of aeration occuring on the suction side of the main pump.
It is desirable that a space axially adjacent to the impeller of the main pump section and connected on its pressure side be selected as the region from which the second passageway leads to the suction side of the priming section. However, it is not essential that this space be at the full pressure of the pressure side of the pump section providing it is sufficient-ly high to produce the desired cooling current.
I't is desirable that a chamber that is axially adjacent to the impeller and connected to the suction side hub region of the impeller be selected as the aforementioned first region.
This region is usually separated from the pressure side of the rotor by a sealing ring slot and is connected to the suction side hub area of the impeller through bores. This selection of the first and second regions is accompanied by the advantage of short passageway to the priming section. This selection of ~, I the regions thereby permits a short and direct connection to the suction side of the pump, where gases which are to be removed collect, and to the pressure side of the impeller. Finally, '~ 30 this selection of the aforementioned regions makes it possible to satisfy the requirement that the passageways discharge into , regions that are at different pressures, so as to ensure the ~' ~L135~
creation of a cooling current -through the aforementloned passaye-ways during normal operation of -the pump.
The invention is independent of whether or not the priming section has a suction chamber that is large in compari-son with the cross section of the passageways. If s~ch a suc-tion port is provided it is desirable that its axial extent be kept small, which is to say, not much greater than the half width of the impeller of the priming section in order that, on the one hand, fluid that is drawn from the main pump section during the priming phase enters the priming section quickly and as completely as possible, and, on the other hand, in order that during normal operation, i.e., during the delivery of liquid, the liquid that flows through the suction chamber passes as directly as possible to the suction side control plate of !
; the priming section. The suction chamber may extend a consid-erable amount in the radial direction for the purpose of pro-~;
viding large-area heat exchange.
It is desirable that a channel be provided which extends from a low region of the main pump section in order that when the priming phase begins, the liquid remaining in the pump is passed to the priming section as operating liquid. How-ever, even in the priming phase itself, considerable pressure can occur at the low point which accordingly is also at a con- ;
siderable distance off the axis. In order that this does not lead to overfilling of the priming section, to which the liquid is passed through the same port as the gas, it is frequently desirable to design the channel with a cross section that will restrict the passage of liquid to the priming section. This also restricts the strength of the cooling stream during normal operation of the pump. In addition, it can lead to the fact that if the first passageway is wide the pressure at the suction opening of the priming section may be very low during normal . , ~L~L3S~
:
opera-tion, an~ thereby promote cavitation. rrhis disadvanta(l~?
can be eliminated if the second passageway, in addition to the channel, also has an opening that discharyes in the main pump section next to the impeller and closer to the shaft than the . channel, that is to say, in a reyion where, because of greater - proximity to the axis, in the priming phase there is yas and not liquid. The passage of liquid to the priming section will :. thereby be restricted, on the one hand, whereas on the other, during normal operation there will be an adequate flow of cool-ing liquid as well as an increase in pressure at -the suction ; port of the priming stage.
The invention will now be described in more detail, ~ by way of example only, with reference to the accompanying draw-.. ings, in which the single Figure is a vertical cross section . through one embodiment of a pump according to the invention.
. The centrifugal pump housing 1 has a suction inlet ,.,~, .
2 and a pressure outlet 3. An impeller 4 has a hub secured to a shaft 5, which in turn is journalled in a bearing 6 mounted ., ~ ~ ., in a plate 7 rigidly fixed to the housing 1. On the rear of ;:; the impeller 4 is a split ring 8, which is located in a groove ::~ in the plate 7 and which with a wall of the yroove forms a . sealing ring. Within the split ring 8 between the rotor 4 and q~ the plate 7 is defined a space 9, which communicates through , . .
.~ pressure equalizing bores 10 to the suction side of the pump `.. `'! in the vicinity of the impeller hub, and in which gas to be l~ : drawn off collects. Extending radially beyond the impeller 4 is ~ a spiral chamber 11, which discharges into the pressure outlet -:` 3 in a manner not shown in the drawing.
Located axially behind the plate 7 is a housing, in-./ 30 cluding a suction side control plate 12 and a pressure side . :
control plate 13, fQr a priming rotor 14. At its periphery, : the suction side control plate 12 is attached securely to the .~ - 5 .
~, . , ., .. ~ , , ~ ~3~1~
' .
plate 7 and defines therewith an annular space 15, which forms a suction chamber of the priming section of the pump. This suction chamber communicates with the priming section working chamber through suction port 25.
The pressure side control plate and a housing cover 16 together form a pressure chamber :L7 of the priming section, with which line 1~ communicates. This line carries exhaust gas either to the pressure outlet 3 of the main section of the pump or into a pressure line connected thereto. A one-way valve can be provided which the line 18 closes if, during the delivery of liquid, the delivery pressure of the impeller 4 is greater than the delivery pressure of the priming rotors. Alternative-ly, the line 18 can vent the exhaust gas to the atmosphere, in which case it is provided with a float valve that closes the line as soon as the priming phase is completed.
Liquid can be supplied from the pressure chamber 17 through a bore 19 to a slip-ring seal 20 for purposes of lubri-cation.
, .
The suction chamber 15 communicates via channel 21 with a low region of the main pump section close to the spiral ~``!` chamber. It contains a constriction 22 to limit the amount of liquid that is passed to the primlng section during the priming phase. In addition, the suction chamber 15 communicates through a passageway 23 with a space between the impeller 4 and the plate 7 that is outside the split ring 8. In the priming phase, the liquid in the main pump is thrown to the outside, where it forms a liquid ring, whereas the central area of the pump is filled with gas. The passageway 23 is then in a region in which there is gas for a considerable part of the priming 30 phase so that flow of liquid to the priming section through the -channel ~ does not occur. In normal operation, however, the region of the main pump section around the passageway 23 is ;:
~L135~19~
.
also filled with llquid so that an addit:ional cooling flow can also occur to -the priming section. For this reason the passageway 23 is arranged in the imrnediate vicinity of the suc-tion port. In addition, the presence of the passageway 23 has the effect of raising the pressure at the suction side of the priming section, which reduces the danger of cavitation.
inally, -the suction chamber 15 of -the priming section communicates with the chamber 9 through the passageway 24, so that gas collecting in the region of the hub of the impeller 4 can be drawn off through the bore 10, the chamber 9 and the passageway 24.
` In the priming phase, liquid flows to the priming .;~ .
; section through the passageway 21. During normal operation, cold ~: liquid flows constantly through the passageway 21 and the pass-, A :
ageway 23 into the suction chamber 15 of the priming section and escapes through the passageway 24. As a result intense cooling occurs in this region. Cooling takes place as a result of liquid flow and heat transfer through the suction side control ~ .~
' plate 12.
In the drawing, the passageways 23 and 24 are shown as being close to each other. It is to be understood, howe~er, that they can be displaced along the periphery, in order to form a longer flow path for the cooling liquid in the suction charnber 15.
~ s ,~
' : , :
.
.~ pressure equalizing bores 10 to the suction side of the pump `.. `'! in the vicinity of the impeller hub, and in which gas to be l~ : drawn off collects. Extending radially beyond the impeller 4 is ~ a spiral chamber 11, which discharges into the pressure outlet -:` 3 in a manner not shown in the drawing.
Located axially behind the plate 7 is a housing, in-./ 30 cluding a suction side control plate 12 and a pressure side . :
control plate 13, fQr a priming rotor 14. At its periphery, : the suction side control plate 12 is attached securely to the .~ - 5 .
~, . , ., .. ~ , , ~ ~3~1~
' .
plate 7 and defines therewith an annular space 15, which forms a suction chamber of the priming section of the pump. This suction chamber communicates with the priming section working chamber through suction port 25.
The pressure side control plate and a housing cover 16 together form a pressure chamber :L7 of the priming section, with which line 1~ communicates. This line carries exhaust gas either to the pressure outlet 3 of the main section of the pump or into a pressure line connected thereto. A one-way valve can be provided which the line 18 closes if, during the delivery of liquid, the delivery pressure of the impeller 4 is greater than the delivery pressure of the priming rotors. Alternative-ly, the line 18 can vent the exhaust gas to the atmosphere, in which case it is provided with a float valve that closes the line as soon as the priming phase is completed.
Liquid can be supplied from the pressure chamber 17 through a bore 19 to a slip-ring seal 20 for purposes of lubri-cation.
, .
The suction chamber 15 communicates via channel 21 with a low region of the main pump section close to the spiral ~``!` chamber. It contains a constriction 22 to limit the amount of liquid that is passed to the primlng section during the priming phase. In addition, the suction chamber 15 communicates through a passageway 23 with a space between the impeller 4 and the plate 7 that is outside the split ring 8. In the priming phase, the liquid in the main pump is thrown to the outside, where it forms a liquid ring, whereas the central area of the pump is filled with gas. The passageway 23 is then in a region in which there is gas for a considerable part of the priming 30 phase so that flow of liquid to the priming section through the -channel ~ does not occur. In normal operation, however, the region of the main pump section around the passageway 23 is ;:
~L135~19~
.
also filled with llquid so that an addit:ional cooling flow can also occur to -the priming section. For this reason the passageway 23 is arranged in the imrnediate vicinity of the suc-tion port. In addition, the presence of the passageway 23 has the effect of raising the pressure at the suction side of the priming section, which reduces the danger of cavitation.
inally, -the suction chamber 15 of -the priming section communicates with the chamber 9 through the passageway 24, so that gas collecting in the region of the hub of the impeller 4 can be drawn off through the bore 10, the chamber 9 and the passageway 24.
` In the priming phase, liquid flows to the priming .;~ .
; section through the passageway 21. During normal operation, cold ~: liquid flows constantly through the passageway 21 and the pass-, A :
ageway 23 into the suction chamber 15 of the priming section and escapes through the passageway 24. As a result intense cooling occurs in this region. Cooling takes place as a result of liquid flow and heat transfer through the suction side control ~ .~
' plate 12.
In the drawing, the passageways 23 and 24 are shown as being close to each other. It is to be understood, howe~er, that they can be displaced along the periphery, in order to form a longer flow path for the cooling liquid in the suction charnber 15.
~ s ,~
' : , :
.
Claims (8)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A self-priming centrifugal pump comprising an im-peller pump mounted on a shaft and forming part of a main pump section, a priming rotor of a side channel or liquid ring pump mounted rigidly on the same shaft and forming part of a priming section, a suction side of the priming section communicating through a first permanently-open passageway with a first region on a suction side of the main pump section where gas to be drawn off collects, the suction side of the priming section also com-municating through a second permanently-open passageway with a second region of the main pump section which, during normal operation, is at a higher pressure than the first region, both the first and second passageways being so designed that in normal operation a stream of liquid sufficient to cool the priming section flows from the second region to the suction side of the priming section and from there to the first region.
2. A centrifugal pump according to Claim 1, wherein the first passageway and the second passageway communicate with each other in the immediate proximity of a suction port of the priming section so that the cooling stream flows in the immediate proximity of the suction port.
3. A centrifugal pump according to Claim 1, wherein the walls of at least one of the first and the second passageways are arranged in close thermally conductive connection with the priming section.
4. A centrifugal pump according to any one of Claims 1 to 3, wherein the second region of the main section is a region at the pressure side thereof close to the impeller.
5. A centrifugal pump according to any one of the Claims 1 to 3, wherein the first region lies in an eye of the impeller.
6. A centrifugal pump according to Claim 2, wherein a suction chamber is located in front of the suction port of the priming section, the axial extent of this suction chamber being not substantially larger than half the width of a rotor of the priming section.
7. A centrifugal pump according to Claim 1, compri-sing a channel communicating with a high pressure region of the main pump section at a low point in the pump where any liquid remaining in the pump drains to.
8. A centrifugal pump according to Claim 7, wherein said second passageway communicates with the main pump section closer to the axis of the impeller than said channel.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE2757952A DE2757952C2 (en) | 1977-12-24 | 1977-12-24 | Self-priming centrifugal pump |
| DEP2757952.8 | 1977-12-24 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1135994A true CA1135994A (en) | 1982-11-23 |
Family
ID=6027237
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000318584A Expired CA1135994A (en) | 1977-12-24 | 1978-12-22 | Self-priming centrifugal pump |
Country Status (13)
| Country | Link |
|---|---|
| US (1) | US4256436A (en) |
| AT (1) | AT362235B (en) |
| BE (1) | BE873027A (en) |
| CA (1) | CA1135994A (en) |
| CH (1) | CH634130A5 (en) |
| DE (1) | DE2757952C2 (en) |
| ES (1) | ES476308A1 (en) |
| FR (1) | FR2412726A1 (en) |
| GB (1) | GB1600183A (en) |
| IN (1) | IN149405B (en) |
| IT (1) | IT1104318B (en) |
| NL (1) | NL181042C (en) |
| SE (1) | SE444210B (en) |
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| JPS56140564A (en) * | 1980-04-01 | 1981-11-02 | Toshiba Corp | Discriminating method for reference position of magnetic head |
| CH669241A5 (en) * | 1985-11-27 | 1989-02-28 | Sulzer Ag | AXIAL PUSH COMPENSATING DEVICE FOR LIQUID PUMP. |
| US4776758A (en) * | 1987-07-06 | 1988-10-11 | Kamyr Ab | Combined fluidizing and vacuum pump |
| FI86333C (en) * | 1988-04-11 | 1992-07-10 | Ahlstroem Oy | FOERFARANDE OCH ANORDNING FOER SEPARERING AV GAS MED PUMPEN UR MEDIET SOM SKALL PUMPAS. |
| DE3842349A1 (en) * | 1988-12-16 | 1990-06-28 | Andreas Szeteli | Non self-priming liquid pump having a bleeding (venting) stage |
| US4981413A (en) * | 1989-04-27 | 1991-01-01 | Ahlstrom Corporation | Pump for and method of separating gas from a fluid to be pumped |
| US4990054A (en) * | 1989-12-13 | 1991-02-05 | Westinghouse Electric Corp. | Device incorporating micro-porous membrane for venting gases from seal assembly of a reactor coolant pump |
| US5116198A (en) * | 1990-09-07 | 1992-05-26 | Ahlstrom Corporation | Centrifugal pumping apparatus |
| US5253986A (en) * | 1992-05-12 | 1993-10-19 | Milton Roy Company | Impeller-type pump system |
| CH689004A5 (en) * | 1993-07-16 | 1998-07-15 | Staehle Martin | Centrifugal pump. |
| US5599171A (en) * | 1995-05-15 | 1997-02-04 | Itt Fluid Technology Corporation | Rotary, self-priming, liquip pump, and an impellers and shaft assembly therefor, and a flexible-impeller pump assembly |
| IT1308195B1 (en) * | 1999-02-23 | 2001-12-10 | Franco Castelmani | TOOL FOR SHRUBING SHRUBS. |
| CN100392250C (en) * | 2005-05-19 | 2008-06-04 | 沈阳市耐蚀合金泵厂 | Central-mounted single-stage and multi-stage double-suction turbine synchronous suction and discharge pump |
| US20110002769A1 (en) * | 2009-07-02 | 2011-01-06 | David Douglas Dieziger | Centrifugal pump for de-watering |
| US9909593B2 (en) | 2009-07-02 | 2018-03-06 | Helen Irene Dieziger | Centrifugal pump for de-watering |
| US8714917B2 (en) * | 2011-02-15 | 2014-05-06 | Liberty Pumps Inc. | Anti-airlock pump |
| CN103352873B (en) * | 2013-07-30 | 2016-04-13 | 强胜精密机械(苏州)有限公司 | The spiral flow constant-pressure pump improved |
| US10830144B2 (en) | 2016-09-08 | 2020-11-10 | Rolls-Royce North American Technologies Inc. | Gas turbine engine compressor impeller cooling air sinks |
| EP3686434A1 (en) | 2019-01-25 | 2020-07-29 | Pentair Flow Technologies, LLC | Self-priming assembly for use in a multi-stage pump |
| DE102020103022B4 (en) | 2020-02-06 | 2022-09-29 | KSB SE & Co. KGaA | pump assembly |
| US11525393B2 (en) | 2020-03-19 | 2022-12-13 | Rolls-Royce Corporation | Turbine engine with centrifugal compressor having impeller backplate offtake |
| US11773773B1 (en) | 2022-07-26 | 2023-10-03 | Rolls-Royce North American Technologies Inc. | Gas turbine engine centrifugal compressor with impeller load and cooling control |
Family Cites Families (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE441484C (en) * | 1923-07-01 | 1927-03-05 | Fritz Neumann Dipl Ing | Centrifugal pump with a water ring pump as a ventilation pump |
| FR843360A (en) * | 1938-03-07 | 1939-07-03 | Emile Salmson Fils De | Improvements to rotary pumps, especially for liquids at high temperature |
| US2780999A (en) * | 1951-12-12 | 1957-02-12 | Borg Warner | Fuel booster pump |
| US2777395A (en) * | 1952-03-12 | 1957-01-15 | Union Steam Pump Company | Pump and packing thereof |
| US2758815A (en) * | 1953-04-17 | 1956-08-14 | Neyrpic Ets | Hydraulic reaction turbine |
| US2949321A (en) * | 1957-01-26 | 1960-08-16 | Borg Warner | Mechanical seal for liquid oxygen pump |
| US3203354A (en) * | 1962-03-26 | 1965-08-31 | Thiokol Chemical Corp | Pump |
| US3174719A (en) * | 1962-06-12 | 1965-03-23 | Dominion Eng Works Ltd | Francis turbines and centrifugal pumps |
| JPS403655B1 (en) * | 1962-11-20 | 1965-02-26 | ||
| GB995322A (en) * | 1963-02-21 | 1965-06-16 | Hamworthy Pumps & Compressors | Centrifugal pump |
| FR1446099A (en) * | 1965-09-01 | 1966-07-15 | Stork Koninklijke Maschf | Vertical pump with automatic suction |
| FR1488654A (en) * | 1966-08-03 | 1967-07-13 | Siemen & Hinsch Gmbh | Self-priming centrifugal pump |
| CH451714A (en) * | 1967-02-15 | 1968-05-15 | Bbc Brown Boveri & Cie | Self-priming centrifugal pump |
| SE7701002L (en) * | 1977-02-01 | 1978-08-02 | Skf Ab | LIQUID-FILLED PUMP MOTOR UNIT |
-
1977
- 1977-12-24 DE DE2757952A patent/DE2757952C2/en not_active Expired
-
1978
- 1978-05-23 GB GB21573/78A patent/GB1600183A/en not_active Expired
- 1978-12-07 CH CH1250678A patent/CH634130A5/en not_active IP Right Cessation
- 1978-12-11 SE SE7812702A patent/SE444210B/en not_active IP Right Cessation
- 1978-12-18 AT AT901278A patent/AT362235B/en not_active IP Right Cessation
- 1978-12-21 IT IT09673/78A patent/IT1104318B/en active
- 1978-12-21 FR FR7835901A patent/FR2412726A1/en active Granted
- 1978-12-22 CA CA000318584A patent/CA1135994A/en not_active Expired
- 1978-12-22 BE BE192524A patent/BE873027A/en not_active IP Right Cessation
- 1978-12-22 US US05/972,357 patent/US4256436A/en not_active Expired - Lifetime
- 1978-12-22 ES ES476308A patent/ES476308A1/en not_active Expired
- 1978-12-23 IN IN1370/CAL/78A patent/IN149405B/en unknown
- 1978-12-27 NL NLAANVRAGE7812562,A patent/NL181042C/en not_active IP Right Cessation
Also Published As
| Publication number | Publication date |
|---|---|
| DE2757952A1 (en) | 1979-07-05 |
| US4256436A (en) | 1981-03-17 |
| IN149405B (en) | 1981-11-28 |
| BE873027A (en) | 1979-04-17 |
| NL181042C (en) | 1991-09-16 |
| FR2412726A1 (en) | 1979-07-20 |
| IT1104318B (en) | 1985-10-21 |
| NL181042B (en) | 1987-01-02 |
| FR2412726B1 (en) | 1985-02-15 |
| ES476308A1 (en) | 1979-07-16 |
| DE2757952C2 (en) | 1983-02-24 |
| AT362235B (en) | 1981-04-27 |
| CH634130A5 (en) | 1983-01-14 |
| IT7809673A0 (en) | 1978-12-21 |
| GB1600183A (en) | 1981-10-14 |
| NL7812562A (en) | 1979-06-26 |
| ATA901278A (en) | 1980-09-15 |
| SE7812702L (en) | 1979-06-25 |
| SE444210B (en) | 1986-03-24 |
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Legal Events
| Date | Code | Title | Description |
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| MKEX | Expiry |