US3269317A - Turbopump arrangement - Google Patents

Turbopump arrangement Download PDF

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Publication number
US3269317A
US3269317A US261558A US26155863A US3269317A US 3269317 A US3269317 A US 3269317A US 261558 A US261558 A US 261558A US 26155863 A US26155863 A US 26155863A US 3269317 A US3269317 A US 3269317A
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United States
Prior art keywords
shaft
pump
propellant
housing
fuel
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Expired - Lifetime
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US261558A
Inventor
Lattanzio Frank
Frank W Reichenbacher
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Raytheon Technologies Corp
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United Aircraft Corp
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Priority to US261558A priority Critical patent/US3269317A/en
Priority to BE664491D priority patent/BE664491A/xx
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Expired - Lifetime legal-status Critical Current

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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02KJET-PROPULSION PLANTS
    • F02K9/00Rocket-engine plants, i.e. plants carrying both fuel and oxidant therefor; Control thereof
    • F02K9/42Rocket-engine plants, i.e. plants carrying both fuel and oxidant therefor; Control thereof using liquid or gaseous propellants
    • F02K9/44Feeding propellants
    • F02K9/46Feeding propellants using pumps
    • F02K9/48Feeding propellants using pumps driven by a gas turbine fed by propellant combustion gases or fed by vaporized propellants or other gases
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01DNON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
    • F01D15/00Adaptations of machines or engines for special use; Combinations of engines with devices driven thereby
    • F01D15/08Adaptations for driving, or combinations with, pumps
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04DNON-POSITIVE-DISPLACEMENT PUMPS
    • F04D13/00Pumping installations or systems
    • F04D13/02Units comprising pumps and their driving means
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04DNON-POSITIVE-DISPLACEMENT PUMPS
    • F04D13/00Pumping installations or systems
    • F04D13/02Units comprising pumps and their driving means
    • F04D13/04Units comprising pumps and their driving means the pump being fluid driven

Definitions

  • This invention relates to a turbine and :pump assembly especially in use for supplying propellant to a rocket.
  • One feature of the invention is an assembly of pumps and turbine such that the pump :for one propellant is on the turbine shaft and the other pump for the other propellant is on a parallel shaft driven at reduced speed through reduction gearing. Another feature is a lubrication and cooling of the bearings and gears with one of the propellants. Another feature is an arrangement of the parts making up the assembly to require a minimum of space and to be of a minimum of weight thereby making the device more useful for rocket application. One other feature is a construction providing for relatively simple assembly and dissassembly of the parts.
  • Another feature of the present invention is controlled leakage of cryogenic fluid propellant past a seal and into the reduction gear chamber for cooling and/ or lubricating purposes.
  • the single figure is a longitudinal sectional view with some parts shown in elevation of the turbine and pump assembly.
  • the assembly is carried by a housing 2 which supports the turbine shaft 4 in spaced bearings 6 and 8 and a laterally spaced parallel shaft 10 in bearings 12 and 14.
  • This housing is made up of a main housing element 16 in the :form generally of an open box having an integral side wall 18.
  • This integral wall incorporates in surrounding relation to the shaft 4 the turbine casing 20' and the high pressure pump casing '22 and forms part of reduction gear chamber 86.
  • Attached to the pump casing 22 is a housing 24 which incorporates the discharge volutes for the low pressure or first stage pump rotor 26 and the high pressure or second stage pump rotor 28.
  • the casing 24 also includes as an integral part a bearing supporting sleeve 30. This sleeve supports the bearing 8 as will be apparent.
  • the casing 24 is attached as by a row of bolts 32 to the casing 22.
  • An inlet housing 34 for the low pressure pump is attached as by bolts 36 through a mounting flange 38 to the casing 24.
  • the casing 34 in turn supports the inducer casing 40.
  • a part of the turbine casing 20 consists of the sleeve 42 which supports the several rows of stator vanes 44, this sleeve being integral with the main housing part 16.
  • the exhaust duct 46 At the downstream end of the sleeve 42 is attached the exhaust duct 46, the latter being held in position as by bolts 48.
  • the housing 16 has within the integral casing 20 a sleeve 50 which supports the bearing 6.
  • the shaft 10 is supported, as above stated, by the bearing 12 which is positioned within a sleeve 52 integral with the main housing 16 and by the bearing 14 positioned within a partition 54 attached to the side wall 18 and to an integral projecting flange 56 on the casing 22.
  • main case 16, including side wall 18, flange 56, cases 22 and 20, and shaft 41, and partition 54 define reduction gear cavity or chamber 86.
  • the partition 54 is connected by webs 58 to the discharge housing 60 having an oxidizer pump rotor 62 carried by the shaft 10.
  • a pump inlet casing 64 surrounds the rotor and is attached as by a bolt 66 to the casing 60.
  • the arrangement is such that the discharge casing 60 for the oxidizer .pump 62 is offset longitudinally with respect to the casing 24 for the fuel pumps but overlaps the casing '24 in a lateral direction thereby permitting a reduction of the transverse dimension of the assembly.
  • the shaft 4 carries a turbine rotor 68 thereon and this turbine rotor serves to drive both the low pressure and high pressure rotors 26 and 28. Since these pump rotors are on the same shaft as the turbine there is no gear loss in the drive therebetween.
  • the inlet casing 34 may support an extension of the shaft 4 by a bearing 70. For this hearing the casing 34 has an inner wall 72 held in position as by vanes 74.
  • the housing 16 supports a jack shaft 76 carrying a gear 78 in mesh with a gear 80 on the shaft 4.
  • the jack shaft also carries a gear 82 smaller than the gear 78 and in mesh with a large diameter gear 84 on the shaft 10.
  • These gears are positioned within a chamber 86 defined between the main wall 16 of the housing and the partition 54.
  • the shaft 10 may carry a second gear 88 in mesh with a gear 90 on an accessory gear shaft 92.
  • the latter is journalled in bearings 94 and 96 carried by the housing.
  • the projecting end of the accessory shaft is surrounded by an accessory mounting ring 98 attached to the main portion of the housing.
  • a seal 100 surrounds the shaft 4 in the end of the high pressure pump casing 22 to control the leakage of fuel around the shaft 4 and into chamber or cavity 86.
  • Seal .100 may be made slightly larger than shaft 4, or longitudinal passages may be drilled thru seal 100 for this purpose.
  • seal 100 is designed to limit the amount of leakage to a predetermined amount of fuel and serves as a controlled vent for fuel from the pump into chamber 86.
  • the size of the seal-toshaft play or the area of the drilled passages will be coordinated with the pressure drop across the seal to determine the amount of fuel leakage across the seal 100 and into chamber 86.
  • the turbine and pump assembly is intended for use in a fuel system supplying both an oxidizer by the pump 62 and a fuel by the pumps 26 and 28 to the injector head of a rocket.
  • a fuel system for which this pump is adapted is described in US. Patent No., 3,028,729, although the arrangement is not limited to this particular system.
  • suitable attachment flanges may be provided for the discharge of oxidizer and for the discharge of fuel from the low pressure pump to the high pressure pump and from the high pressure pump to the first point of use of the fuel.
  • the assemblage is such that the several components may be readily removed from one another for replacement. Thus, should any part of the assemblage require replacement, disassembly of the device to permit replacement can be readily accomplished.
  • the device is arranged so that the propellant systems are separated one from another to .prevent mixing of the propellants in any way that might produce an explosive mixture. Escape of hydrogen or fuel from the chamber 86 past the bearing 96 is prevented by a suitable seal 102 and leakage of the fuel past the bearing 14 toward the oxidizer pump is prevented by a seal 104. Also at this location a seal 106 surrounds the shaft to prevent leakage of oxidizer along the shaft 10 toward the bearing 14. A vent 108 permits the escape of such small amounts of oxidizer or fuel as may pass the seals 104 and 106. This mixture is of such a low density and in such small quantities as not to be serious.
  • a turbopump assembly for a rocket including a housing, laterally spaced substantially parallel shafts journalled therein, a pump for a first propellant mounted on the first shaft, a turbine on said first shaft for driving said first propellant pump, a second propellant pump on the second shaft, reduction gearing between the shafts, a partition in said housing to define a chamber therein for the gearing, and means for controllably passing a selected quantity of said first propellant from said first propellant pump into said chamber.
  • a turbopump assembly as in claim 1 in which the housing also supports an accessory shaft and gearing within the chamber drives the accessory shaft from said other shaft.
  • a turbopump assembly as in claim 2 in which seals on said second shaft between the pump and the partition 4. limit the escape of oxidizer and fuel along said shaft and in which the fluids leaking past the seals are vented to a point outside the chamber.
  • a turbopump assembly as in claim 1 in which the pumps have axial inlets at the same end of the housing.
  • a turbopump assembly as in claim 2 in which the fuel pump is a two-stage pump with the two stages of the pump arranged in back-to-back arrangement on said shaft.
  • a turbopump assembly as in claim 2 in which the fuel and oxidizer pumps for surrounding stators and in which the volute for the pump on said one shaft overlies the stator for the pump on said other shaft in a direction at right angles to said shafts.
  • a turbopump assembly for a rocket including a supporting structure, laterally spaced shafts journalled therein in parallel relation to each other, a turbine on one of said shafts at one end thereof, a pump mounted on said one shaft in axially spaced relation to the turbine, a gear on said shaft between the pump and turbine, reduction gearing between said shafts and engaging with the first mentioned gear and a pump mounted on the other of said shafts, each of the shafts having a supporting structure positioned on opposite sides of the reduction gearing.
  • a turbopump assembly as in claim 2 in which the bearings and gears are cooled by fuel from the fuel pump.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Structures Of Non-Positive Displacement Pumps (AREA)

Description

g- 30, 1965 F. LATTANZIO ETAL 3, 6 ,317
TURBOPUMP ARRANGEMENT Filed Feb.
INVENTORS FRANK LATTA/VZ/O FRANK WREIGHENBACHER ATTORNEY United States Patent 3,269,317 TURBOPUMP ARRANGEMENT Frank Lattanzio, West Hartford, Conn., and Frank W. Reichenbacher, Scottsdale, Ariz., assignors to United Aircraft Corporation, East Hartford, Conn., a corporation of Delaware Filed Feb. 21, 1963, Ser. No. 261,558 9 Claims. (Cl. 103-6) This is a continuation-in-part application of US. patent application Serial No. 21,829, filed April 12, 1960, now abandoned on improvements in Turbopump Arrangement by Frank Lattanzio and Frank W. Reichenbacher.
This invention relates to a turbine and :pump assembly especially in use for supplying propellant to a rocket.
One feature of the invention is an assembly of pumps and turbine such that the pump :for one propellant is on the turbine shaft and the other pump for the other propellant is on a parallel shaft driven at reduced speed through reduction gearing. Another feature is a lubrication and cooling of the bearings and gears with one of the propellants. Another feature is an arrangement of the parts making up the assembly to require a minimum of space and to be of a minimum of weight thereby making the device more useful for rocket application. One other feature is a construction providing for relatively simple assembly and dissassembly of the parts.
Another feature of the present invention is controlled leakage of cryogenic fluid propellant past a seal and into the reduction gear chamber for cooling and/ or lubricating purposes.
Other features and advantages will be apparent from the specification and claims, and from the accompanying drawing which illustrates an embodiment of the invention.
The single figure is a longitudinal sectional view with some parts shown in elevation of the turbine and pump assembly.
The assembly is carried by a housing 2 which supports the turbine shaft 4 in spaced bearings 6 and 8 and a laterally spaced parallel shaft 10 in bearings 12 and 14. This housing is made up of a main housing element 16 in the :form generally of an open box having an integral side wall 18. This integral wall incorporates in surrounding relation to the shaft 4 the turbine casing 20' and the high pressure pump casing '22 and forms part of reduction gear chamber 86. Attached to the pump casing 22 is a housing 24 which incorporates the discharge volutes for the low pressure or first stage pump rotor 26 and the high pressure or second stage pump rotor 28. The casing 24 also includes as an integral part a bearing supporting sleeve 30. This sleeve supports the bearing 8 as will be apparent. The casing 24 is attached as by a row of bolts 32 to the casing 22.
An inlet housing 34 for the low pressure pump is attached as by bolts 36 through a mounting flange 38 to the casing 24. The casing 34 in turn supports the inducer casing 40. These several casing elements described all become essentially a part of the housing for the assembly.
A part of the turbine casing 20 consists of the sleeve 42 which supports the several rows of stator vanes 44, this sleeve being integral with the main housing part 16. At the downstream end of the sleeve 42 is attached the exhaust duct 46, the latter being held in position as by bolts 48. The housing 16 has within the integral casing 20 a sleeve 50 which supports the bearing 6.
The shaft 10 is supported, as above stated, by the bearing 12 which is positioned within a sleeve 52 integral with the main housing 16 and by the bearing 14 positioned within a partition 54 attached to the side wall 18 and to an integral projecting flange 56 on the casing 22. It will be seen that main case 16, including side wall 18, flange 56, cases 22 and 20, and shaft 41, and partition 54 define reduction gear cavity or chamber 86. The partition 54 is connected by webs 58 to the discharge housing 60 having an oxidizer pump rotor 62 carried by the shaft 10. A pump inlet casing 64 surrounds the rotor and is attached as by a bolt 66 to the casing 60. The arrangement is such that the discharge casing 60 for the oxidizer .pump 62 is offset longitudinally with respect to the casing 24 for the fuel pumps but overlaps the casing '24 in a lateral direction thereby permitting a reduction of the transverse dimension of the assembly.
The shaft 4 carries a turbine rotor 68 thereon and this turbine rotor serves to drive both the low pressure and high pressure rotors 26 and 28. Since these pump rotors are on the same shaft as the turbine there is no gear loss in the drive therebetween. The inlet casing 34 may support an extension of the shaft 4 by a bearing 70. For this hearing the casing 34 has an inner wall 72 held in position as by vanes 74.
Between the shafts 4 and 10 the housing 16 supports a jack shaft 76 carrying a gear 78 in mesh with a gear 80 on the shaft 4. The jack shaft also carries a gear 82 smaller than the gear 78 and in mesh with a large diameter gear 84 on the shaft 10. These gears are positioned within a chamber 86 defined between the main wall 16 of the housing and the partition 54.
The shaft 10 may carry a second gear 88 in mesh with a gear 90 on an accessory gear shaft 92. The latter is journalled in bearings 94 and 96 carried by the housing. The projecting end of the accessory shaft is surrounded by an accessory mounting ring 98 attached to the main portion of the housing.
A seal 100 surrounds the shaft 4 in the end of the high pressure pump casing 22 to control the leakage of fuel around the shaft 4 and into chamber or cavity 86. Seal .100 may be made slightly larger than shaft 4, or longitudinal passages may be drilled thru seal 100 for this purpose. -In this or other known fashion, seal 100 is designed to limit the amount of leakage to a predetermined amount of fuel and serves as a controlled vent for fuel from the pump into chamber 86. The size of the seal-toshaft play or the area of the drilled passages will be coordinated with the pressure drop across the seal to determine the amount of fuel leakage across the seal 100 and into chamber 86. Such fuel leakage, from the inlet to the high pressure pump 28, enters chamber 86 and provides for lubrication and/or cooling of the bearings, gears and related parts therein. Since the fuel will be cryogenic, the cooling effect will be most beneficial.
The turbine and pump assembly is intended for use in a fuel system supplying both an oxidizer by the pump 62 and a fuel by the pumps 26 and 28 to the injector head of a rocket. A fuel system for which this pump is adapted is described in US. Patent No., 3,028,729, although the arrangement is not limited to this particular system. It will be understood that suitable attachment flanges may be provided for the discharge of oxidizer and for the discharge of fuel from the low pressure pump to the high pressure pump and from the high pressure pump to the first point of use of the fuel. The assemblage is such that the several components may be readily removed from one another for replacement. Thus, should any part of the assemblage require replacement, disassembly of the device to permit replacement can be readily accomplished.
The device is arranged so that the propellant systems are separated one from another to .prevent mixing of the propellants in any way that might produce an explosive mixture. Escape of hydrogen or fuel from the chamber 86 past the bearing 96 is prevented by a suitable seal 102 and leakage of the fuel past the bearing 14 toward the oxidizer pump is prevented by a seal 104. Also at this location a seal 106 surrounds the shaft to prevent leakage of oxidizer along the shaft 10 toward the bearing 14. A vent 108 permits the escape of such small amounts of oxidizer or fuel as may pass the seals 104 and 106. This mixture is of such a low density and in such small quantities as not to be serious.
It is to be understood that the invention is not limited to the specific embodiment herein illustrated and described, but may be used in other Ways without departure from its spirit as defined by the following claims.
We claim:
1. A turbopump assembly for a rocket, including a housing, laterally spaced substantially parallel shafts journalled therein, a pump for a first propellant mounted on the first shaft, a turbine on said first shaft for driving said first propellant pump, a second propellant pump on the second shaft, reduction gearing between the shafts, a partition in said housing to define a chamber therein for the gearing, and means for controllably passing a selected quantity of said first propellant from said first propellant pump into said chamber.
2. A turbopump assembly as in claim 1 wherein said first propellant is fuel and said second propellant is an oxidizer and in which the reduction gears are carried by bearings within the housing with the fuel providing coolant for the bearings and gears.
3. A turbopump assembly as in claim 1 in which the housing also supports an accessory shaft and gearing within the chamber drives the accessory shaft from said other shaft.
4. A turbopump assembly as in claim 2 in which seals on said second shaft between the pump and the partition 4. limit the escape of oxidizer and fuel along said shaft and in which the fluids leaking past the seals are vented to a point outside the chamber.
5. A turbopump assembly as in claim 1 in which the pumps have axial inlets at the same end of the housing.
6. A turbopump assembly as in claim 2 in which the fuel pump is a two-stage pump with the two stages of the pump arranged in back-to-back arrangement on said shaft.
7. A turbopump assembly as in claim 2 in which the fuel and oxidizer pumps for surrounding stators and in which the volute for the pump on said one shaft overlies the stator for the pump on said other shaft in a direction at right angles to said shafts.
8. A turbopump assembly for a rocket, including a supporting structure, laterally spaced shafts journalled therein in parallel relation to each other, a turbine on one of said shafts at one end thereof, a pump mounted on said one shaft in axially spaced relation to the turbine, a gear on said shaft between the pump and turbine, reduction gearing between said shafts and engaging with the first mentioned gear and a pump mounted on the other of said shafts, each of the shafts having a supporting structure positioned on opposite sides of the reduction gearing.
9. A turbopump assembly as in claim 2 in which the bearings and gears are cooled by fuel from the fuel pump.
No references cited.
MARK NEWMAN, Primary Examiner.
BENJAMIN A. BORCHELT, Examiner.
WILLIAM L. FREEH, Assistant Examiner.

Claims (1)

1. A TURBOPUMP ASSEMBLY FOR A ROCKET, INCLUDING A HOUSING, LATERALLY SPACED SUBSTANTIALLY PARALLEL SHAFTS JOURNALLED THEREIN, A PUMP FOR A FIRST PROPELLANT MOUNTED ON THE FIRST SHAFT, A TURBINE ON SAID FIRST SHAFT FOR DRIVING SAID FIRST PROPELLANT PUMP, A SECOND PROPELLANT PUMP ON THE SECOND SHAFT, REDUCTION GEARING BETWEEN THE SHAFTS, A PARTITION IN SAID HOUSING TO DEFINE A CHAMBER THEREIN FOR THE GEARING, AND MEANS FOR CONTROLLABLY PASSING A SELECTED QUANTITY OF SAID FIRST PROPELLANT FROM SAID FIRST PROPELLANT PUMP INTO SAID CHAMBER.
US261558A 1963-02-21 1963-02-21 Turbopump arrangement Expired - Lifetime US3269317A (en)

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3761205A (en) * 1972-03-20 1973-09-25 Avco Corp Easily maintainable gas turbine engine
US4373858A (en) * 1980-12-10 1983-02-15 The Bendix Corporation Flow regulating shaft seal for an air motor
US4622818A (en) * 1984-04-24 1986-11-18 David Flaxington Bearing system for a gas turbine

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
None *

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3761205A (en) * 1972-03-20 1973-09-25 Avco Corp Easily maintainable gas turbine engine
US4373858A (en) * 1980-12-10 1983-02-15 The Bendix Corporation Flow regulating shaft seal for an air motor
US4622818A (en) * 1984-04-24 1986-11-18 David Flaxington Bearing system for a gas turbine

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Publication number Publication date
BE664491A (en) 1965-09-16

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