EP3896288A1 - Zentrifugalpumpe zum fördern eines fluids - Google Patents

Zentrifugalpumpe zum fördern eines fluids Download PDF

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Publication number
EP3896288A1
EP3896288A1 EP21159213.4A EP21159213A EP3896288A1 EP 3896288 A1 EP3896288 A1 EP 3896288A1 EP 21159213 A EP21159213 A EP 21159213A EP 3896288 A1 EP3896288 A1 EP 3896288A1
Authority
EP
European Patent Office
Prior art keywords
sealing device
pump
branch
centrifugal pump
shaft
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.)
Withdrawn
Application number
EP21159213.4A
Other languages
English (en)
French (fr)
Inventor
Marc Widmer
Arnaldo Rodrigues
Daniele Cimmino
Thomas Welschinger
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Sulzer Management AG
Original Assignee
Sulzer Management AG
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Sulzer Management AG filed Critical Sulzer Management AG
Publication of EP3896288A1 publication Critical patent/EP3896288A1/de
Withdrawn legal-status Critical Current

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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
    • F04D15/00—Control, e.g. regulation, of pumps, pumping installations or systems
    • F04D15/0005—Control, e.g. regulation, of pumps, pumping installations or systems by using valves
    • F04D15/0022—Control, e.g. regulation, of pumps, pumping installations or systems by using valves throttling valves or valves varying the pump inlet opening or the outlet opening
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D1/00—Radial-flow pumps, e.g. centrifugal pumps; Helico-centrifugal pumps
    • F04D1/06—Multi-stage pumps
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D15/00—Control, e.g. regulation, of pumps, pumping installations or systems
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D15/00—Control, e.g. regulation, of pumps, pumping installations or systems
    • F04D15/0005—Control, e.g. regulation, of pumps, pumping installations or systems by using valves
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D29/00—Details, component parts, or accessories
    • F04D29/04—Shafts or bearings, or assemblies thereof
    • F04D29/041—Axial thrust balancing
    • F04D29/0416—Axial thrust balancing balancing pistons
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D29/00—Details, component parts, or accessories
    • F04D29/04—Shafts or bearings, or assemblies thereof
    • F04D29/043—Shafts
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D29/00—Details, component parts, or accessories
    • F04D29/08—Sealings
    • F04D29/10—Shaft sealings
    • F04D29/102—Shaft sealings especially adapted for elastic fluid pumps
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D29/00—Details, component parts, or accessories
    • F04D29/08—Sealings
    • F04D29/10—Shaft sealings
    • F04D29/106—Shaft sealings especially adapted for liquid pumps
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D29/00—Details, component parts, or accessories
    • F04D29/18—Rotors
    • F04D29/22—Rotors specially for centrifugal pumps
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D29/00—Details, component parts, or accessories
    • F04D29/40—Casings; Connections of working fluid
    • F04D29/42—Casings; Connections of working fluid for radial or helico-centrifugal pumps
    • F04D29/426—Casings; Connections of working fluid for radial or helico-centrifugal pumps especially adapted for liquid pumps
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D29/00—Details, component parts, or accessories
    • F04D29/66—Combating cavitation, whirls, noise, vibration or the like; Balancing
    • F04D29/669—Combating cavitation, whirls, noise, vibration or the like; Balancing especially adapted for liquid pumps
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D29/00—Details, component parts, or accessories
    • F04D29/70—Suction grids; Strainers; Dust separation; Cleaning
    • F04D29/708—Suction grids; Strainers; Dust separation; Cleaning specially for liquid pumps

Definitions

  • the invention relates to a centrifugal pump for conveying a fluid in accordance with the preamble of the independent claim.
  • Centrifugal pumps for conveying a fluid for example a liquid such as water
  • a fluid for example a liquid such as water
  • Centrifugal pumps have at least one impeller and a shaft for rotating the impeller.
  • the at least one impeller may be configured for example as a radial impeller or as an axial or semi-axial impeller or as a helicoaxial impeller.
  • the impeller may be configured as an open impeller or as a closed impeller, where a shroud is provided on the impeller, said shroud at least partially covering the vanes of the impeller.
  • a centrifugal pump may be designed as a single stage pump having only one impeller mounted to the shaft or as a multistage pump comprising a plurality of impellers, wherein the impellers are arranged in series on the shaft.
  • the balancing device may comprise a balance drum for at least partially balancing the axial thrust that is generated by the rotating impellers.
  • the balance drum is fixedly connected to the shaft of the pump in a torque proof manner.
  • the balance drum is arranged at the discharge side of the pump between the last stage impeller and a shaft sealing device.
  • the balance drum defines a front side and a back side. The front side is the side facing the last stage impeller. The back side is the side facing the shaft sealing device.
  • a relief passage is provided between the balance drum and a stationary part being stationary with respect to the pump housing.
  • the back side is usually connected to the suction side of the pump by means of a balance line.
  • the pressure difference between the front side and the back side results in a axial force or an axial thrust which is directed in the opposite direction as the axial thrust generated by the rotating impeller(s).
  • the axial thrust that has to be carried by the axial or thrust bearing is at least considerably reduced.
  • the relief passage is configured such, that the leakage flow is as low as possible but still sufficient for generating the axial thrust counteracting the axial thrust generated by the impeller(s).
  • a centrifugal pump has at least one shaft seal device for sealing the shaft against a leakage of the fluid along the shaft.
  • the rotating shaft and all impellers are arranged between two shaft sealing devices, which are typically arranged next to the bearings at the drive end and at the non-drive end of the shaft, respectively.
  • the sealing devices may be configured for example as a mechanical seal.
  • a mechanical seal comprises a stator and a rotor.
  • the rotor is connected in a torque-proof manner with the shaft of the pump and the stator is fixed with respect to the pump housing such that the stator is secured against rotation.
  • a liquid e.g. the fluid conveyed by the pump or any other lubricant is supplied to the mechanical seal for generating a fluid film between the stator and the rotor.
  • a sealing device such as a mechanical seal requires cooling for removing the heat from the sealing device, as well as flushing to keep particles away from the sealing elements. Therefore a certain flow is required for cooling and flushing. It is a known measure that the flow required to flush and to cool the sealing devices is extracted either at or near the outlet of the pump or at an intermediate stage of the pump. This required flow for flushing the sealing devices causes additional losses which reduces the efficiency of the pump.
  • a centrifugal pump for conveying a fluid comprising a pump housing with an inlet at a suction side and an outlet at a discharge side, at least one impeller for conveying the fluid from the inlet to the outlet, a shaft for rotating the impeller about an axial direction, a first sealing device for sealing the shaft at the suction side, a second sealing device for sealing the shaft at the discharge side, a balance drum fixedly connected to the shaft and arranged between the at least one impeller and the second sealing device, wherein the balance drum defines a front side facing the at least one impeller and a back side facing the second sealing device, wherein a relief passage is provided between the balance drum and a stationary part configured to be stationary with respect to the pump housing, wherein the relief passage extends from the front side to the back side, wherein a balance line is provided connecting the back side with the suction side, wherein a discharge opening is arranged at the relief passage between the front side and the back side, and wherein a connecting line is
  • a pressure prevails that is at most slightly higher than the suction pressure at the suction side of the pump.
  • the pressure at the discharge opening in the relief passage is considerably higher than the suction pressure. Therefore the flow of fluid in the connecting line is directed towards the first sealing device and may be used for flushing the first sealing device.
  • the connecting line comprises at least one flow control element for controlling the flow through the connecting line.
  • the flow control element may be, for example, a valve or an orifice.
  • the connecting line comprises a first branch and a second branch, wherein the first branch is connected with the first sealing device, and the second branch is connected with the second sealing device.
  • the flow discharged from the relief passage through the discharge opening and the connecting line is additionally used to also flush the second sealing device.
  • the first branch comprises a first flow control element for controlling the flow through the first branch
  • the second branch comprises a second flow control element for controlling the flow through the second branch.
  • the connecting line comprises a third branch, wherein the third branch is connected to the suction side.
  • the third branch may be connected for example to the inlet of the pump or to the balance line or to a suction tank being in fluid communication with the inlet of the pump.
  • the flow extracted from the relief passage may be routed directly back to the suction side, i.e. without passing through one of the sealing devices, for example if the extracted flow exceeds the required flow for the sealing devices or if the pressure requires an adjustment.
  • the third branch is particularly advantageous to adjust the leakage flow through the relief passage.
  • the third branch comprises a third flow control element for controlling the flow through the third branch.
  • At least one of the flow control elements is configured as an adjustable valve.
  • each flow control element is configured as an adjustable valve.
  • the first sealing device comprises a mechanical seal.
  • the second sealing device comprises a mechanical seal.
  • the pump is configured as a multistage pump having a plurality of impellers, wherein the impellers are arranged one after another on the shaft.
  • the pump is configured as a between-bearing pump.
  • the pump may be configured as a barrel type pump comprising an outer barrel casing, in which the pump housing is arranged.
  • Fig. 1 shows a schematic cross-sectional view of an embodiment of a centrifugal pump according to the invention, which is designated in its entity with reference numeral 1.
  • the pump 1 is designed as a centrifugal pump for conveying a fluid, for example a liquid such as water.
  • the centrifugal pump 1 comprises a pump housing 2 having an inlet 3 and an outlet 4 for the fluid to be conveyed.
  • the inlet 3 is arranged at a suction side S, where a suction pressure prevails, and the outlet 4 is arranged at a discharge side D, where a discharge pressure prevails.
  • the suction pressure is also referred to as low pressure, and the discharge pressure is also referred to as high pressure.
  • the centrifugal pump 1 further comprises at least one impeller 5, 51 for conveying the fluid from the inlet 3 to the outlet 4 as indicated by the dashed arrows without reference numerals, as well as a shaft 6 for rotating each impeller 5, 51 about an axial direction A.
  • the axial direction A is defined by the axis of the shaft 6.
  • Each impeller 5, 51 is mounted to the shaft 6 in a torque proof manner.
  • the shaft 6 has a drive end 61, which may be connected to a drive unit (not shown) for driving the rotation of the shaft 6 about the axial direction.
  • the drive unit may comprise, for example, an electric motor.
  • the other end of the shaft 6 is referred to as non-drive end 62.
  • the centrifugal pump 1 is configured as a multistage pump 1 having a plurality of impellers 5, 51, wherein the impellers 5, 51 are arranged one after another on the shaft 6.
  • the reference numeral 51 designates the last stage impeller 51, which is the impeller 51 closest to the outlet 4.
  • the last stage impeller 51 pressurizes the fluid to the discharge pressure.
  • the embodiment shown in Fig. 1 has nine stages, which has to be understood exemplary.
  • the plurality of impellers 5, 51 may be arranged in an in-line configuration as shown in Fig. 1 or in a back-to-back configuration.
  • the multistage centrifugal pump 1 shown in Fig. 1 is designed as a horizontal pump, meaning that during operation the shaft 6 is extending horizontally, i.e. the axial direction A is perpendicular to the direction of gravity.
  • the centrifugal pump 1 shown in Fig. 1 may be designed as a horizontal barrel casing multistage pump 1, i.e. as a double-casing pump.
  • the multistage pump 1 may be designed, for example, as a pump 1 of the pump type BB5 according to API 610.
  • the centrifugal pump 1 comprises an outer barrel casing 100, in which the pump housing 2 is arranged.
  • the centrifugal pump may be configured without an outer barrel casing, for example as a BB4 type pump, or as an axially split multistage pump, or as a single stage pump, or as a vertical pump, meaning that during operation the shaft 6 is extending in the vertical direction, which is the direction of gravity, or as any other type of centrifugal pump.
  • the centrifugal pump 1 comprises bearings on both sides of the plurality of impellers 5, 51 (with respect to the axial direction A), i.e. the centrifugal pump 1 is designed as a between-bearing pump.
  • a first radial bearing 81, a second radial bearing 82 and an axial bearing 83 are provided for supporting the shaft 6.
  • the first radial bearing 81 is arranged adjacent to the drive end 61 of the shaft 6.
  • the second radial bearing 82 is arranged adjacent or at the non-drive end 62 of the shaft 6.
  • the axial bearing 83 is arranged between the plurality of impellers 5, 51 and the first radial bearing 81 adjacent to the first radial bearing 81.
  • the bearings 81, 82, 83 are configured to support the shaft 6 both in the axial direction A and in a radial direction, which is a direction perpendicular to the axial direction A.
  • the radial bearings 81 and 82 are supporting the shaft 6 with respect to the radial direction
  • the axial bearing 83 is supporting the shaft 6 with respect to the axial direction A.
  • the first radial bearing 81 and the axial bearing 83 are arranged such that the first radial bearing 81 is closer to the drive end 61 of the shaft 6.
  • it is also possible to exchange the position of the first radial bearing 81 and the axial bearing 83 i.e. to arrange the first radial bearing 81 between the axial bearing 83 and the plurality of impellers 5, 51, so that the axial bearing 83 is closer to the drive end 61 of the shaft 6.
  • a radial bearing such as the first or the second radial bearing 81 or 82 is also referred to as a "journal bearing” and an axial bearing, such as the axial bearing 83, is also referred to as an "thrust bearing”.
  • the first radial bearing 81 and the axial bearing 83 may be configured as separate bearings as shown in Fig. 1 , but it is also possible that the first radial bearing 81 and the axial bearing 83 are configured as a single combined radial and axial bearing supporting the shaft both in radial and in axial direction.
  • the second radial bearing 82 is supporting the shaft 6 in radial direction.
  • an axial bearing for the shaft 6 is provided at the non-drive end 62.
  • a second axial bearing may be provided at the drive end 61 or the drive end 61 may be configured without an axial bearing.
  • the centrifugal pump 1 further comprises two sealing devices, namely a first sealing device 91 for sealing the shaft 6 at the suction side S and a second sealing device 92 for sealing the shaft 6 at the discharge side D.
  • first sealing device 91 is arranged between the plurality of impellers 5 an the second radial bearing 82
  • the second sealing device 92 is arranged between the last stage impeller 51 and the axial pump bearing 83.
  • Both sealing devices 91, 92 seal the shaft 6 against a leakage of the fluid along the shaft 6 e.g. into the environment.
  • the sealing devices 91 and 92 the fluid may be prevented from entering the bearings 81, 82, 83.
  • each sealing device 91, 92 comprises a mechanical seal.
  • Mechanical seals are well-known in the art in many different embodiments and therefore require no detailed explanation.
  • a mechanical seal is a seal for a rotating shaft 6 and comprises a rotor fixed to the shaft 6 and rotating with the shaft 6, as well as a stationary stator fixed with respect to the pump housing 2.
  • the rotor and the stator are sliding along each other - usually with a liquid as lubricant there between - for providing a sealing action to prevent the fluid from escaping to the environment or entering the bearings 81, 82, 83.
  • a separate bearing isolator is provided which prevents liquids or solids to enter the bearings 81, 82, 83.
  • the sealing devices 91, 92 e.g. the mechanical seals prevent the fluid from leaking into the environment.
  • the centrifugal pump 1 further comprises a balance drum 7 for at least partially balancing the axial thrust that is generated by the impellers 5, 51 during operation of the centrifugal pump 1.
  • the balance drum 7 is fixedly connected to the shaft 6 in a torque proof manner.
  • the balance drum 7 is arranged at the discharge side D between the last stage impeller 51 and the second sealing device 92.
  • the balance drum 7 defines a front side 71 and a back side 72.
  • the front side 71 is the side facing the last stage impeller 51.
  • the back side 72 is the side facing the second sealing device 92.
  • the balance drum 7 is surrounded by a stationary part 21, so that a relief passage 73 is formed between the radially outer surface of the balance drum 7 and the stationary part 21.
  • the stationary part 21 is configured to be stationary with respect to the pump housing 2.
  • the relief passage 73 forms an annular gap between the outer surface of the balance drum 7 and the stationary part 21 and extends from the front side 71 to the back side 72.
  • the front side 71 is in fluid communication with the outlet 4, so that the axial surface of the balance drum 7 facing the front side 71 is exposed essentially to the discharge pressure prevailing at the outlet 4 during operation of the pump 1.
  • the pressure prevailing at the axial surface of the balance drum 7 facing the front side 71 may be somewhat smaller than the discharge pressure.
  • the considerably larger pressure drop takes place over the balance drum 7.
  • a chamber 74 is provided, which is connected by a balance line 10 with the suction side S, e.g. with the inlet 3.
  • the pressure in the chamber 74 at the back side 72 is somewhat larger than the suction pressure due to the pressure drop over the balance line 10 but considerably smaller than the discharge pressure.
  • the balance line 10 is provided for recirculating the fluid from the chamber 74 at the back side 72 to the suction side S. A part of the pressurized fluid passes from the front side 71 through the relief passage 73 to the back side 72, enters the balance line 10 and is recirculated to the suction side S of the centrifugal pump 1.
  • the balance line 10 constitutes a flow connection between the back side 72 and the suction side S at the pump inlet 3.
  • the balance line 10 may be arranged - as shown in Fig. 1 - outside the pump housing 2 and inside the barrel casing 100. In other embodiments the balance line 10 may be designed as internal line completely extending within the pump housing 2. In still other embodiments the balance line may be arranged outside the barrel casing 100.
  • a discharge opening 70 is arranged at the relief passage 73 between the front side 71 and the back side 72 and a connecting line 40 is provided for connecting the discharge opening 70 with the first sealing device 91.
  • a part of the flow passing through the relief passage 73 enters the connecting line 40 through the discharge opening 70 and is guided to the first sealing device 91 for flushing and cooling the first sealing device 91.
  • the pressure at the discharge opening 70 is an intermediate pressure, which is smaller than the discharge pressure at the outlet 4 of the pump 1 and larger than the pressure in the chamber 74 at the back side 72 that is a bit larger than the suction pressure at the suction side S of the centrifugal pump 1.
  • the pressure in the first sealing device 91 e.g. the pressure in the sealing chamber of the mechanical seal, is at most slightly higher than the suction pressure, so that this pressure in the first sealing device 91 is considerably lower than the intermediate pressure prevailing at the discharge opening 70.
  • the flow discharged through the connecting line 40 can be used for flushing the first sealing device 91 in order to cool the first sealing device 91 down and to keep particles away from the sealing elements of the first sealing device 91.
  • a volume of the pumped fluid is constantly extracted from the relief passage 72, guided through the connecting line 40 and injected into the first sealing device 91 for flushing. Consequently, there is no need to extract pressurized fluid at any other location e.g.
  • FIG. 2 some preferred measures and variants are explained, each of which may be realized in particular in the embodiment shown in Fig. 1 . Since it is sufficient for the understanding, in Fig. 2 only one impeller is shown, which may be for example the only impeller of a single stage pump or the last stage impeller 51 of a multistage pump.
  • Fig. 2 shows a cross-sectional view illustrating a configuration of the balance drum 7 and the connecting line 40.
  • the connecting line 40 as well as the balance line 10 are at least partially represented as single lines in Fig. 2 , wherein the direction of flow trough the particular line is indicated by the arrows without reference numeral.
  • the Fluid flowing through the pump 1 is indicated by the dashed arrows without reference numeral.
  • the connecting line 40 comprises at least one flow control element, namely a first flow control element 45, for controlling the flow through the connecting line 40 into the first sealing device 91.
  • the first flow control element 45 may be designed as a throttle or as a orifice or as a valve such as a flow control valve or any other adjustable valve. With the first flow control element 45 the flushing volumetric flow injected into the first sealing device 91 may be adjusted.
  • the connecting line 40 may comprise a first branch 41 and a second branch 42, wherein the first branch 41 is connected with the first sealing device 91, and the second branch 42 is connected with the second sealing device 92. If the first flow control element 45 is provided in this design, the first flow control element 45 is arranged in the first branch 41.
  • the second branch 42 of the connecting line 40 comprises a second flow control element 46, for controlling the flow through the second branch 42 into the second sealing device 92.
  • the second flow control element 46 may be designed as a throttle or as a orifice or as a valve such as a flow control valve or any other adjustable valve. With the second flow control element 46 the flushing volumetric flow injected into the second sealing device 92 may be adjusted.
  • the connecting line 40 comprises a third branch 43, wherein the third branch 43 is connected to the suction side S.
  • the third branch 43 may be connected for example to the inlet 3 of the centrifugal pump 1 or to a tank, from which the fluid is supplied to the inlet 3 of the centrifugal pump 1.
  • the third branch 43 leads into the balance line 10.
  • the third branch 43 of the connecting line 40 comprises a third flow control element 47, for controlling the flow through the third branch 43 leading to the suction side S.
  • the third flow control element 47 may be designed as a throttle or as a orifice or as a valve such as a flow control valve or any other adjustable valve.
  • the centrifugal pump 1 renders possible to control and to adjust the balancing flow passing through the relief passage 72 and the balance line 10, i.e. the flow that is recirculated through the balance line 10 can be adjusted. Said adjustment may be realized by regulating the flow passing through the discharge opening 70 into the connecting line 40. Thus, by controlling the flow through the connecting line 40 the balance flow recirculated to the suction side S can be adjusted. This is in particular advantageous for such embodiments of the centrifugal pump 1, that are designed for high to very high discharge pressures and a low discharge flow.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Structures Of Non-Positive Displacement Pumps (AREA)
EP21159213.4A 2020-04-16 2021-02-25 Zentrifugalpumpe zum fördern eines fluids Withdrawn EP3896288A1 (de)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP20169858 2020-04-16

Publications (1)

Publication Number Publication Date
EP3896288A1 true EP3896288A1 (de) 2021-10-20

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EP21159213.4A Withdrawn EP3896288A1 (de) 2020-04-16 2021-02-25 Zentrifugalpumpe zum fördern eines fluids

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US (1) US20210324862A1 (de)
EP (1) EP3896288A1 (de)
CN (1) CN113530835A (de)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US12006949B2 (en) * 2018-11-21 2024-06-11 Sulzer Management Ag Multiphase pump

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SG10201912904SA (en) * 2019-02-18 2020-09-29 Sulzer Management Ag Process fluid lubricated pump and seawater injection system

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1528717A1 (de) * 1965-06-30 1969-10-30 Halbergerhuette Gmbh Vorrichtung zum Ausgleich des Axialschubes bei mehrstufigen Kreiselpumpen
EP0224764A1 (de) * 1985-11-27 1987-06-10 GebràœDer Sulzer Aktiengesellschaft Axialschub-Ausgleichsvorrichtung für Flüssigkeitspumpe
EP3121450A1 (de) * 2015-07-23 2017-01-25 Sulzer Management AG Pumpe zum fördern eines fluids mit variierender viskosität

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1528717A1 (de) * 1965-06-30 1969-10-30 Halbergerhuette Gmbh Vorrichtung zum Ausgleich des Axialschubes bei mehrstufigen Kreiselpumpen
EP0224764A1 (de) * 1985-11-27 1987-06-10 GebràœDer Sulzer Aktiengesellschaft Axialschub-Ausgleichsvorrichtung für Flüssigkeitspumpe
EP3121450A1 (de) * 2015-07-23 2017-01-25 Sulzer Management AG Pumpe zum fördern eines fluids mit variierender viskosität

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US12006949B2 (en) * 2018-11-21 2024-06-11 Sulzer Management Ag Multiphase pump

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CN113530835A (zh) 2021-10-22
US20210324862A1 (en) 2021-10-21

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