US3516757A - Labyrinth seal for a hydraulic rotary machine - Google Patents

Labyrinth seal for a hydraulic rotary machine Download PDF

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Publication number
US3516757A
US3516757A US739335A US3516757DA US3516757A US 3516757 A US3516757 A US 3516757A US 739335 A US739335 A US 739335A US 3516757D A US3516757D A US 3516757DA US 3516757 A US3516757 A US 3516757A
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United States
Prior art keywords
machine
parts
water
runner
gap
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Expired - Lifetime
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US739335A
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English (en)
Inventor
Kurt Baumann
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Sulzer Escher Wyss AG
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Escher Wyss AG
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F03—MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
    • F03B—MACHINES OR ENGINES FOR LIQUIDS
    • F03B11/00—Parts or details not provided for in, or of interest apart from, the preceding groups, e.g. wear-protection couplings, between turbine and generator
    • F03B11/006—Sealing arrangements
    • 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
    • F04D29/16—Sealings between pressure and suction sides
    • F04D29/165—Sealings between pressure and suction sides especially adapted for liquid pumps
    • F04D29/167—Sealings between pressure and suction sides especially adapted for liquid pumps of a centrifugal flow wheel
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E10/00—Energy generation through renewable energy sources
    • Y02E10/20—Hydro energy

Definitions

  • the relative position of the parts bounding the sealing gap on either side is variable from a position intended for rotation of the runner in water, in which the width of the sealing gap is comparatively small, to a position with increased gap width intended for rotation of the runner in air.
  • This may be eifected by the non-rotating part bounding the sealing gap being displaceable in the machine housing and being connected to one or more servomotors by intermediate members, for example shift rods. It is possible in this way to advance this part to the working position for rotation of the runner in water "ice and to form the necessary narrow gap in this way. If the machine is to be operated in air, the displaceable part is moved by means of the servomotors until the sealing gap is sufficiently wide.
  • the servomotors necessary for actuating the slidable part of the labyrinth seal may be of any desired and known form.
  • hydraulically or pneumatically operated servomotors or even simple lever mechanisms or spindles driven by electric motor may be used.
  • the labyrinth seal With the construction of the labyrinth seal according to the invention, it is possible substantially to reduce the power losses of the hydraulic machine during operation in the emptied condition, that is to say, therefore, during rotation of the runner in air. This is attributable to the fact that the said power losses mainly occur owing to the hitherto necessary supply of water to the gaps, as well as to rotor disc friction. In the application of the concept according to the invention, the only power loss remaining, apart from friction losses in the bearings, is the driving power necessary to overcome windage losses.
  • Machine sets of usual type of storage pump installations comprise, as a rule, an electrical machine, which may be operated as generator and as motor, as well as a turbine and storage pump.
  • the storage pump is as a rule uncoupled, because the power losses of the storage pump rotating in air with labyrinth seals supplied with water are so high that economic operation is frequently doubtful.
  • cases are known in which obviously for the same reason the turbine is uncoupled during operation of the pump.
  • the machine set of the storage pump installation may thus be limited to the three "principal machines, namely the electrical machine, turbine and storage pump. If the most rational arrangement is considered, a common shaft and two bearings suffice for three machine units. As a further consequence of the simplification, compared with the conventional construction, the substantially small space requirement must be mentioned, accompanied by correspondingly lower building costs.
  • a storage pump installation in which the rotary hydraulic machine or machines are provided with the labyrinth seals constructed according to the invention furthermore permits shorter change-over times between the individual methods of operation than can be realised with the conventional construction.
  • both hydraulic machines are empty.
  • the storage pump may be accelerated directly from stoppage in the water-filled condition or in the empty condition by putting the turbine into operation.
  • the subject of the invention may also be used advantageously in the case in which the machine set comprises a reversible pump turbine.
  • Acceleration to pump operation is eifected as a rule in known manner by means of a separate rigidly coupled electric starting motor with the pump turbine empty, the runner rotating in air.
  • the size or design of the starting motor depends, among other things, also on the power loss of the runner rotating in air.
  • these losses may be substantially reduced, so that the starting motor may be designed for a lower power. This is particularly important if suflicient time is available for acceleration in pump operation, so that starting motor torque to be applied may be relatively small.
  • the losses occurring during phase-shifter operation which occur as is known in the empty pump turbine, are also substantially reduced.
  • FIG. 1 shows a diagrammatic longitudinal section through the rotary machine in the region of the labyrinth seals, the parts bounding the sealing gaps being in the position intended for rotation of the runner in water, and
  • FIG. 2 shows the same longitudinal section, in which, however, the parts bounding the sealing gaps are in the position intended for rotation of the runner in air.
  • the rotary machine shown only partly in the drawings, may be a Francis turbine, a centrifugal pump or a reversible pump turbine.
  • the runner 1 On the hub side, the runner 1 is sealed by means of a comb-like labyrinth seal 2, and on the rim side by means of a stepped labyrinth seal 3 relative to the stationary parts 4, 5 and 6, 7, respectively, of the housing.
  • the comb-like seal 2 has a sealing gap 8 on one side only of the combs, while a larger gap 8' is provided on the other side.
  • the sealing gap of the labyrinth seal 3 At 9 is shown the sealing gap of the labyrinth seal 3.
  • the sealing gaps 8 and 9 are bounded by nonrotating annular parts 10 and 11, axially displaceable in the housing parts 5 and 7, respectively, and connected by intermediate members 12 to one or more hydraulic or pneumatic servomotors 13.
  • bounda- .ries of the sealing gaps 8 and 9 are formed directly by corresponding coaxial annular parts 15 of the runner hub and runner rim, respectively.”
  • Each of the servomotors 13 consists of a housing 17 and a piston 18 slidable therein and rigidly connected to the corresponding intermediate member 12.
  • chambers 19 and 20 are provided on either side of the piston 18 and are adapted to be connected by ducts 21 and 22 via control valves, not shown, to a pressure fluid source.
  • the parts 10 and 11 may be moved by means of the servomotors 13 in the axial direction of the machine between two end positions, one of which is shown in FIG. 1 and the other in FIG.
  • each of these parts is equipped with a centering stop, provided with a conical surface 24, which in the position according to FIG. 1 bears on a corresponding conical surface 23 of the housing parts 4 and 6, respectively, thus ensuring non-play connection with the machine housing.
  • the parts 10 and 11 are constructed as annular pistons, and in the position according to FIG. 1 bound with the housing 4, 5 and 6, 7, respectively, an annular chamber 25 communicating via one or more ducts 26 with the pressure water space 27 of the machine.
  • the effect of this step is that during operation with water in the position according to FIG. 1, the parts 10 and 11 are forced automatically by the water pressure in the annular chambers 25 against the stop surfaces 23 of the housing.
  • the servomotors 13 have then only to be designed for producing the forces necessary for the displacement of the parts 10 and 11.
  • the parts 10 and 11 are brought into the position shown in FIG. 2 by means of the servomotors 13.
  • the sealing gaps 8 and 9 are bounded by stepped cylindrical surfaces.
  • the parts 10 and 11, with reference to the position according to FIG. 1 have been moved in the axial direction away from the runner 1 by an amount corresponding substantially to the axial length of a step.
  • the gap width has thus been increased in each case by the amount of one step height.
  • ducts 28 leading respectively to the sealing gaps 8 and 9 are provided, these ducts being in communication with a longitudinal bore passing through the intermediate member 12.
  • the longitudinal bore of the member 12 in turn is connected to a chamber 29, recessed in the servomotor housing 17 and adapted to be charged from outside with pressure water.
  • the pressure water supplied passes through the bore in the intermediate member 12 and the duct 28 as coolant to the sealing gaps 8 and 9, respectively.
  • the water supply should continue until the position shown in FIG. 2 is reached, that is to say, until the gap has been increased.
  • the pressure'water supply should be interrupted only when the hydraulic rotary machine has been filled with water for actualoperation.
  • a variation in the width of the sealing gaps 8 and 9 on displacement of the parts 10 and 11 would also be obtained if the sealing gaps 8 and 9 were to be bounded by conical surfaces instead of stepped cylindrical surfaces.
  • a width of sealing gap, sufiicient for operation of the runner in air, would then possibly be obtained even for a smaller variation in position of the displaceable part than in the case of the stepped boundary surfaces.
  • Labyrinth seals with sealing gaps bounded by conical surfaces have been found to be particularly disadvantagous in practice, especially in the case of large hydraulic machines, because their sealing efrect varies appreciably even with slight axial displacement of the runner. Continuous variation of the width of the sealing gap and therefore also of the efiiciency of the machine and of the axial thrust may occur in operation. For this reason, in a labyrinth seal according to the invention, stepped cylindrical boundary surfaces are to be preferred for the sealing gap.
  • a hydraulic rotary machine operable in either of two conditions, namely a water-filled condition and an air-filled condition, said machine comprising a housing; a runner arranged for rotation in said housing; means defining a water fiow path leading through said housing and said runner; at least one labyrinth, seal formed by a annular part of said runner and a coaxial non-rotating annular part of said housing arranged to bound a gap between one another; said annular parts of the runner and the housing being shiftable axially relatively to one another; and stop means preventing axial movement of said annular parts into contact with each other and effective in the water-filled condition of the machine to establish a predetermined minimum sealing gap between said annular parts, and effective in the air-filled condition of the machine to establish a predetermined larger gap.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Hydraulic Turbines (AREA)
  • Ignition Installations For Internal Combustion Engines (AREA)
US739335A 1967-07-03 1968-06-24 Labyrinth seal for a hydraulic rotary machine Expired - Lifetime US3516757A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CH943567A CH467941A (de) 1967-07-03 1967-07-03 Labyrinthdichtung an einer hydraulischen Kreiselmaschine, deren Läufer zeitweise in Wasser und zeitweise in Luft umläuft.

Publications (1)

Publication Number Publication Date
US3516757A true US3516757A (en) 1970-06-23

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ID=4351955

Family Applications (1)

Application Number Title Priority Date Filing Date
US739335A Expired - Lifetime US3516757A (en) 1967-07-03 1968-06-24 Labyrinth seal for a hydraulic rotary machine

Country Status (9)

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US (1) US3516757A (en:Method)
AT (1) AT288285B (en:Method)
CH (1) CH467941A (en:Method)
DE (1) DE1750937A1 (en:Method)
ES (1) ES355708A1 (en:Method)
FR (1) FR1570899A (en:Method)
GB (1) GB1226772A (en:Method)
IE (1) IE32178B1 (en:Method)
NO (1) NO123276B (en:Method)

Cited By (24)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4126360A (en) * 1975-12-02 1978-11-21 Escher Wyss Limited Francis-type hydraulic machine
US4131386A (en) * 1977-05-05 1978-12-26 Sundstrand Corporation Sealing system for centrifugal pump
US4286919A (en) * 1979-12-13 1981-09-01 Hitachi, Ltd. Apparatus for pumping operation of a hydraulic machine having Francis type runner
US4405283A (en) * 1980-06-19 1983-09-20 M.A.N. Maschinenfabrik Augsburg-Nurnberg Aktiengesellschaft Gas turbine construction and method of controlling the labyrinth seal clearance automatically and continuously
US4459082A (en) * 1981-09-30 1984-07-10 Sundstrand Corporation Self-acting automatic clearance control apparatus for a turbine
US4465284A (en) * 1983-09-19 1984-08-14 General Electric Company Scalloped cooling of gas turbine transition piece frame
US4588352A (en) * 1984-04-12 1986-05-13 Kabushiki Kaisha Toshiba Multistage hydraulic machine
US4909706A (en) * 1987-01-28 1990-03-20 Union Carbide Corporation Controlled clearance labyrinth seal
US5975537A (en) * 1997-07-01 1999-11-02 General Electric Company Rotor and stator assembly configured as an aspirating face seal
US6739829B2 (en) * 2002-07-08 2004-05-25 Giw Industries, Inc. Self-compensating clearance seal for centrifugal pumps
US20050123395A1 (en) * 2003-12-03 2005-06-09 Addie Graeme R. Self-compensating clearance seal for centrifugal pumps
US20060008348A1 (en) * 2004-07-07 2006-01-12 Hitachi Industries Co., Ltd. Turbo-type fluid machine and a stepped seal apparatus to be used therein
US20070160465A1 (en) * 2006-01-10 2007-07-12 Roudnev Aleksander S Flexible floating ring seal arrangement for rotodynamic pumps
CN101813101A (zh) * 2010-03-19 2010-08-25 江苏大学 一种固液两相流离心泵密封口环防磨损装置
US20100303615A1 (en) * 2007-12-28 2010-12-02 Alstom Hydro France Hydraulic machine, an energy conversion installation including such a machine, and a method of adjusting such a machine
WO2013004321A1 (de) * 2011-07-01 2013-01-10 Voith Patent Gmbh Pumpturbinenanlage
US20130330169A1 (en) * 2011-01-18 2013-12-12 Voith Patent Gmbh Water Turbine
US20140030086A1 (en) * 2012-07-26 2014-01-30 GM Global Technology Operations LLC Centrifugal pump
US20170321713A1 (en) * 2014-11-27 2017-11-09 Robert Bosch Gmbh Compressor having a sealing channel
US20180030986A1 (en) * 2016-07-28 2018-02-01 General Electric Company Engine with face seal
CN107762569A (zh) * 2016-08-19 2018-03-06 中国航发商用航空发动机有限责任公司 非接触式篦齿封严结构及航空发动机、燃气轮机
US10161411B1 (en) * 2017-10-20 2018-12-25 Halliburton Energy Services, Inc. Centrifugal pump sealing surfaces
US20190211699A1 (en) * 2018-01-09 2019-07-11 General Electric Company Turbine engine with a seal
CN114033706A (zh) * 2021-11-17 2022-02-11 嘉利特荏原泵业有限公司 一种离心泵

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4335886A (en) * 1980-07-22 1982-06-22 Cornell Pump Company Labyrinth seal with current-forming sealing passages
GB2159895B (en) * 1984-06-04 1987-09-16 Gen Electric Stepped-tooth rotating labyrinth seal
DE19540745A1 (de) * 1995-11-02 1997-05-07 Asea Brown Boveri Verdichterrad-Wellenverbindung
DE102017007860A1 (de) 2017-08-23 2019-02-28 Wilo Se Abdichtung am Saugmund eines Pumpenlaufrades

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR599264A (en:Method) * 1926-01-08
US1823702A (en) * 1928-05-24 1931-09-15 Allis Chalmers Mfg Co Hydraulic machine
FR1074886A (fr) * 1953-02-10 1954-10-11 Neyrpic Ets Perfectionnements aux turbines
US3174719A (en) * 1962-06-12 1965-03-23 Dominion Eng Works Ltd Francis turbines and centrifugal pumps
US3226083A (en) * 1961-04-05 1965-12-28 English Electric Co Ltd Reversible pump turbines
US3330532A (en) * 1966-03-23 1967-07-11 Baldwin Lima Hamilton Corp Thrust control means for hydraulic machines

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR599264A (en:Method) * 1926-01-08
US1823702A (en) * 1928-05-24 1931-09-15 Allis Chalmers Mfg Co Hydraulic machine
FR1074886A (fr) * 1953-02-10 1954-10-11 Neyrpic Ets Perfectionnements aux turbines
US3226083A (en) * 1961-04-05 1965-12-28 English Electric Co Ltd Reversible pump turbines
US3174719A (en) * 1962-06-12 1965-03-23 Dominion Eng Works Ltd Francis turbines and centrifugal pumps
US3330532A (en) * 1966-03-23 1967-07-11 Baldwin Lima Hamilton Corp Thrust control means for hydraulic machines

Cited By (36)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4126360A (en) * 1975-12-02 1978-11-21 Escher Wyss Limited Francis-type hydraulic machine
US4131386A (en) * 1977-05-05 1978-12-26 Sundstrand Corporation Sealing system for centrifugal pump
US4286919A (en) * 1979-12-13 1981-09-01 Hitachi, Ltd. Apparatus for pumping operation of a hydraulic machine having Francis type runner
US4405283A (en) * 1980-06-19 1983-09-20 M.A.N. Maschinenfabrik Augsburg-Nurnberg Aktiengesellschaft Gas turbine construction and method of controlling the labyrinth seal clearance automatically and continuously
US4459082A (en) * 1981-09-30 1984-07-10 Sundstrand Corporation Self-acting automatic clearance control apparatus for a turbine
US4465284A (en) * 1983-09-19 1984-08-14 General Electric Company Scalloped cooling of gas turbine transition piece frame
US4588352A (en) * 1984-04-12 1986-05-13 Kabushiki Kaisha Toshiba Multistage hydraulic machine
US4909706A (en) * 1987-01-28 1990-03-20 Union Carbide Corporation Controlled clearance labyrinth seal
US5975537A (en) * 1997-07-01 1999-11-02 General Electric Company Rotor and stator assembly configured as an aspirating face seal
US6739829B2 (en) * 2002-07-08 2004-05-25 Giw Industries, Inc. Self-compensating clearance seal for centrifugal pumps
US20050123395A1 (en) * 2003-12-03 2005-06-09 Addie Graeme R. Self-compensating clearance seal for centrifugal pumps
US7189054B2 (en) * 2003-12-03 2007-03-13 Giw Industries, Inc. Self-compensating clearance seal for centrifugal pumps
US20060008348A1 (en) * 2004-07-07 2006-01-12 Hitachi Industries Co., Ltd. Turbo-type fluid machine and a stepped seal apparatus to be used therein
US7338255B2 (en) * 2004-07-07 2008-03-04 Hitachi Industries Co., Ltd. Turbo-type fluid machine and a stepped seal apparatus to be used therein
US20070160465A1 (en) * 2006-01-10 2007-07-12 Roudnev Aleksander S Flexible floating ring seal arrangement for rotodynamic pumps
US7429160B2 (en) 2006-01-10 2008-09-30 Weir Slurry Group, Inc. Flexible floating ring seal arrangement for rotodynamic pumps
US20100303615A1 (en) * 2007-12-28 2010-12-02 Alstom Hydro France Hydraulic machine, an energy conversion installation including such a machine, and a method of adjusting such a machine
US8882445B2 (en) * 2007-12-28 2014-11-11 Alstom Renewable Technologies Hydraulic machine, an energy conversion installation including such a machine, and a method of adjusting such a machine
AU2008345485B2 (en) * 2007-12-28 2014-05-01 Alstom Renewable Technologies Hydraulic machine, energy conversion plant comprising such a machine and method of adjusting such a machine
CN101813101A (zh) * 2010-03-19 2010-08-25 江苏大学 一种固液两相流离心泵密封口环防磨损装置
US20130330169A1 (en) * 2011-01-18 2013-12-12 Voith Patent Gmbh Water Turbine
WO2013004321A1 (de) * 2011-07-01 2013-01-10 Voith Patent Gmbh Pumpturbinenanlage
CN103080534A (zh) * 2011-07-01 2013-05-01 沃依特专利有限责任公司 泵涡轮机设备
US20130045086A1 (en) * 2011-07-01 2013-02-21 Manfred Stummer Pump-Turbine Plant
RU2596411C2 (ru) * 2011-07-01 2016-09-10 Фойт Патент Гмбх Насосно-турбинная установка
US20140030086A1 (en) * 2012-07-26 2014-01-30 GM Global Technology Operations LLC Centrifugal pump
US20170321713A1 (en) * 2014-11-27 2017-11-09 Robert Bosch Gmbh Compressor having a sealing channel
WO2018022314A1 (en) * 2016-07-28 2018-02-01 General Electric Company Turbine engine with aspirating face seal
US20180030986A1 (en) * 2016-07-28 2018-02-01 General Electric Company Engine with face seal
US10823184B2 (en) * 2016-07-28 2020-11-03 General Electric Company Engine with face seal
CN107762569A (zh) * 2016-08-19 2018-03-06 中国航发商用航空发动机有限责任公司 非接触式篦齿封严结构及航空发动机、燃气轮机
CN107762569B (zh) * 2016-08-19 2020-01-14 中国航发商用航空发动机有限责任公司 非接触式篦齿封严结构及航空发动机、燃气轮机
US10161411B1 (en) * 2017-10-20 2018-12-25 Halliburton Energy Services, Inc. Centrifugal pump sealing surfaces
US20190211699A1 (en) * 2018-01-09 2019-07-11 General Electric Company Turbine engine with a seal
US10781709B2 (en) * 2018-01-09 2020-09-22 General Electric Company Turbine engine with a seal
CN114033706A (zh) * 2021-11-17 2022-02-11 嘉利特荏原泵业有限公司 一种离心泵

Also Published As

Publication number Publication date
IE32178B1 (en) 1973-05-02
ES355708A1 (es) 1970-03-01
FR1570899A (en:Method) 1969-06-13
DE1750937A1 (de) 1972-04-06
AT288285B (de) 1971-02-25
IE32178L (en) 1969-01-03
NO123276B (en:Method) 1971-10-18
CH467941A (de) 1969-01-31
GB1226772A (en:Method) 1971-03-31

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