GB2135022A - Improvements in or relating to impeller pumps particularly for fire fighting - Google Patents

Improvements in or relating to impeller pumps particularly for fire fighting Download PDF

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Publication number
GB2135022A
GB2135022A GB08303966A GB8303966A GB2135022A GB 2135022 A GB2135022 A GB 2135022A GB 08303966 A GB08303966 A GB 08303966A GB 8303966 A GB8303966 A GB 8303966A GB 2135022 A GB2135022 A GB 2135022A
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GB
United Kingdom
Prior art keywords
unloading valve
high pressure
valve
stage
automatic unloading
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.)
Granted
Application number
GB08303966A
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GB2135022B (en
GB8303966D0 (en
Inventor
Stephen Walker Tebby
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.)
Individual
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Individual
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 Individual filed Critical Individual
Priority to GB08303966A priority Critical patent/GB2135022B/en
Publication of GB8303966D0 publication Critical patent/GB8303966D0/en
Publication of GB2135022A publication Critical patent/GB2135022A/en
Application granted granted Critical
Publication of GB2135022B publication Critical patent/GB2135022B/en
Expired 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
    • F04D15/0016—Control, e.g. regulation, of pumps, pumping installations or systems by using valves mixing-reversing- or deviation 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
    • F04D1/00—Radial-flow pumps, e.g. centrifugal pumps; Helico-centrifugal pumps
    • F04D1/06—Multi-stage pumps
    • F04D1/10—Multi-stage pumps with means for changing the flow-path through the stages, e.g. series-parallel, e.g. side loads
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
    • F16K31/00—Actuating devices; Operating means; Releasing devices
    • F16K31/12—Actuating devices; Operating means; Releasing devices actuated by fluid
    • F16K31/36—Actuating devices; Operating means; Releasing devices actuated by fluid in which fluid from the circuit is constantly supplied to the fluid motor
    • F16K31/363—Actuating devices; Operating means; Releasing devices actuated by fluid in which fluid from the circuit is constantly supplied to the fluid motor the fluid acting on a piston

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  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Fire-Extinguishing By Fire Departments, And Fire-Extinguishing Equipment And Control Thereof (AREA)
  • Control Of Non-Positive-Displacement Pumps (AREA)

Abstract

An automatic unloading valve 3 is provided whereby the fluid contained in a high pressure stage 2 of an impeller pump may be unloaded when only a low pressure stage is being used. The unloading valve 5 comprises a closure member 7 resiliently urged to an open position. When high pressure flow is required, shut-off valve 10 is opened and pump outlet pressure rises. The unloading valve maintains a communication path between the high pressure outlet stage and the low pressure inlet stage until such time as the quantity of fluid transported through it reaches a predetermined rate at which point the thrust provided by spring 9 is exceeded and the unloading valve closes. <IMAGE>

Description

SPECIFICATION Improvements in or relating to impeller pumps particularly for fire fighting This invention relates to an improved method of unloading the high pessure stage of an impeller pump when only the low pressure stage is being used, such as is required in impeller pumps for fire fighting.
The fire fighting service requires pumps for two separate pumping duties. Firstly, large powerful streams of water are needed for which a pump should deliver a comparatively large volume of say 750 gal/min at a low pressure of say 100 Ibf/in2. Secondly a low volume, high pressure delivery is needed for production of water fog. A fog nozzle will commonly pass twenty gal/min and it is customary for a fire appliance to be fitted with two of these nozzles so that the high pressure delivery should be at least 40 gal/min at a pressure of 350 to 600 Ibf/in2.
Fire fighting pumps are generally of a centrifugal type e.g. as described in Martlew, G.K., "Fire Engines", I. Mech.E. Proc., Vol.
182, Pt. 2A, No. 7, 1967-68, orofa combined centrifugal and regenerative type as specified in UK Patent 1 234587 or of a 2 stage type with interstage jet pump as spcified in GB 2012870A.
Fire fighting pumps which are capable of providing both low and high pressure extinguishant or water are frequently called on in service to provide only low pressure delivery.
On these occasions it is desirable to ensure that the high pressure stage is empty of water in order to reduce pumping and churning losses to a minimum. A shut-off valve is generally provided between the output of the low pressure stage and the input of the high pressure stage. Also, in order to ensure that any water which internally leaks through into the high pressure stage or is purposely bled to the high pressure stage for seal cooling, then a second valve can be provided which allows such water to be guided back to pump inlet.
In GB 1 234587 this valve is automatic in operation having 3 fluid passages connecting to it; the first connects to the low-to-high pressure shut-off valve, the second to the high pressure outlet and the third to the low pressure inlet. The corresponding valve in GB 201 2870A is hand operated and is embodied into the shut-off valve which connects the low pressure outlet to the jet pump inlet.
The drawback with both aforementioned systems is that fluid carrying passageways and pipework are lengthy and cumbersome and the valve arrangements complex.
In accordance with the present invention an unloading valve assembly comprises an inlet duct which is arranged to be connected to the pump delivery, an outlet duct through which liquid may be discharged back to pump suc tion, and a valve body which contains a closure member resiliently urged to an open position. The construction of the unloading valve is such that it provides a communication path between the said pump delivery and the pump suction until such time as the quantity of liquid transported through the unloading valve reaches a predetermined rate at which point it is automatically closed.
The unloading valve may be positioned on a horizontal plane through the lowest point of the pump delivery casing to which the valve is connected. In this manner, its location may be shared with a drain valve. It will be appreci ated that this is not the only location of the unloading valve in which it will function in its intending manner.
The configuration thus described is compact compared with other unloading systems cur rently available and it has the advantage of being fully automatic.
One example of an unloading valve system constructed in accordance with the invention is illustrated in accompanying drawing Fig. 1.
Passageway 1 connects the outlet side of one of the high pressure stages 2 to the unloading valve body 3. Passageway 4 connects the unloading valve body 3 to the impeller pump suction 5. Drain cock 6 may be connected to either passageways 1 or 4 or not at all. Valve piston 7 which need not necessarily be a close fit in the unloading valve body may be fitted with a seat 8. The spring 9 or any suitable resiliently urging device produces an axial load on the valve piston. The construc tion may be similar to a conventional relief or check valve except that the spring force acts in the opposite direction to the spring force normally contained in such valves and the fluid is transported through the valve in a direction opposite to the direction normally associated with such valves.
When only low pressure delivery is required the shutt off valve 10 is closed so water is no longer admitted to the high pressure stage.
With no appreciable water inlet to the high pressure stage, the pressure at the outlet to the high pressure stage drops and at a predet ermined pressure the unloading valve opens.
The spring load in the valve is sufficient to keep the valve in the open position when a small water flow rate corresponding to the internal leakage rate plus seal coolant flow is pumped through it back to suction.
When high pressure flow is required again, the shut off valve 10 is opened and pump outlet pressure rapidly rises causing an in crease in flow through the unloading valve.
The geometry of the valve is arranged such that at a predetermined flow rate through it, the forces on the valve piston are sufficient to close the valve to a position shown in Fig. 2.
The unloading valve geometry is further ar ranged so that it remains in a closed position due to all working pressures developed by the high pressure stage.

Claims (4)

1. An automatic unloading valve which allows high pressure stage or stages to be evacuated when those stages are not producing high pressure.
2. An automatic unloading valve according to Claim 1 which has an inlet and an outlet passageway with no other fluid connections except an optional drain cock facility.
3. An automatic unloading valve assembly according to Claims 1 and 2 in which a valve body contains a closure member held open by a spring.
4. An automatic unloading valve substantially as described with reference to the accompanying drawings.
GB08303966A 1983-02-14 1983-02-14 Improvements in or relating to impeller pumps particularly for fire fighting Expired GB2135022B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB08303966A GB2135022B (en) 1983-02-14 1983-02-14 Improvements in or relating to impeller pumps particularly for fire fighting

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB08303966A GB2135022B (en) 1983-02-14 1983-02-14 Improvements in or relating to impeller pumps particularly for fire fighting

Publications (3)

Publication Number Publication Date
GB8303966D0 GB8303966D0 (en) 1983-03-16
GB2135022A true GB2135022A (en) 1984-08-22
GB2135022B GB2135022B (en) 1986-05-21

Family

ID=10537926

Family Applications (1)

Application Number Title Priority Date Filing Date
GB08303966A Expired GB2135022B (en) 1983-02-14 1983-02-14 Improvements in or relating to impeller pumps particularly for fire fighting

Country Status (1)

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GB (1) GB2135022B (en)

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1996031703A1 (en) * 1995-04-03 1996-10-10 Murray William E Centrifugal process pump with booster impeller
WO1998034030A1 (en) * 1997-02-04 1998-08-06 Murray William E Centrifugal process pump with auxiliary impeller
GB2338747A (en) * 1998-06-26 1999-12-29 Godiva Limited Two stage pump with low and high pressure output, a thermal relief valve and a filter
FR2891880A1 (en) * 2005-10-11 2007-04-13 Renault Sas Cooling circuit`s pump for coolant circulation in internal combustion engine, has valve setting circulation circuit in communication with another circuit at high functioning rate, and deviating coolant from latter circuit to former circuit
FR2891879A1 (en) * 2005-10-11 2007-04-13 Renault Sas Cooling circuit`s pump for coolant circulation in internal combustion engine, has valve setting circulation circuit in communication with another circuit at high functioning rate and deviating coolant from latter circuit to former circuit
CN100462565C (en) * 2006-05-18 2009-02-18 威乐水泵有限公司 Automatic pump
FR2950941A1 (en) * 2009-10-05 2011-04-08 Arbatax DOUBLE ELECTRIC PUMP FOR THE MAINTENANCE OF SWIMMING POOLS
AT521729A3 (en) * 2018-10-11 2020-09-15 Albert Ziegler Gmbh Pump device

Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB262920A (en) * 1925-11-30 1926-12-23 James Rollo Walker Improvements in and connected with pumps
GB675701A (en) * 1950-01-18 1952-07-16 Gen Motors Corp Improvements relating to liquid fuel supply systems
GB680127A (en) * 1949-10-04 1952-10-01 Rolls Royce Improvements in or relating to gas turbine power plants
GB913483A (en) * 1960-09-02 1962-12-19 Gen Motors Corp Gas turbine engine fuel system
GB969354A (en) * 1961-11-13 1964-09-09 Jacques De Matteis Adsorbent filter apparatus
GB1229292A (en) * 1967-06-26 1971-04-21
GB1234587A (en) * 1968-09-27 1971-06-03
GB1383467A (en) * 1972-06-16 1974-02-12 Rosenbauer Kg Konrad Fire-fighting centrifugal pump
GB2007300A (en) * 1977-11-08 1979-05-16 Chandler Evans Inc Pumping systems
GB1552988A (en) * 1975-08-22 1979-09-19 Inter Ocean Nv High pressure conduit system for fluids comprising a closing member

Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB262920A (en) * 1925-11-30 1926-12-23 James Rollo Walker Improvements in and connected with pumps
GB680127A (en) * 1949-10-04 1952-10-01 Rolls Royce Improvements in or relating to gas turbine power plants
GB675701A (en) * 1950-01-18 1952-07-16 Gen Motors Corp Improvements relating to liquid fuel supply systems
GB913483A (en) * 1960-09-02 1962-12-19 Gen Motors Corp Gas turbine engine fuel system
GB969354A (en) * 1961-11-13 1964-09-09 Jacques De Matteis Adsorbent filter apparatus
GB1229292A (en) * 1967-06-26 1971-04-21
GB1234587A (en) * 1968-09-27 1971-06-03
GB1383467A (en) * 1972-06-16 1974-02-12 Rosenbauer Kg Konrad Fire-fighting centrifugal pump
GB1552988A (en) * 1975-08-22 1979-09-19 Inter Ocean Nv High pressure conduit system for fluids comprising a closing member
GB2007300A (en) * 1977-11-08 1979-05-16 Chandler Evans Inc Pumping systems

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1996031703A1 (en) * 1995-04-03 1996-10-10 Murray William E Centrifugal process pump with booster impeller
US5599164A (en) * 1995-04-03 1997-02-04 Murray; William E. Centrifugal process pump with booster impeller
WO1998034030A1 (en) * 1997-02-04 1998-08-06 Murray William E Centrifugal process pump with auxiliary impeller
GB2338747A (en) * 1998-06-26 1999-12-29 Godiva Limited Two stage pump with low and high pressure output, a thermal relief valve and a filter
GB2338747B (en) * 1998-06-26 2002-04-10 Godiva Ltd Pumps
FR2891880A1 (en) * 2005-10-11 2007-04-13 Renault Sas Cooling circuit`s pump for coolant circulation in internal combustion engine, has valve setting circulation circuit in communication with another circuit at high functioning rate, and deviating coolant from latter circuit to former circuit
FR2891879A1 (en) * 2005-10-11 2007-04-13 Renault Sas Cooling circuit`s pump for coolant circulation in internal combustion engine, has valve setting circulation circuit in communication with another circuit at high functioning rate and deviating coolant from latter circuit to former circuit
CN100462565C (en) * 2006-05-18 2009-02-18 威乐水泵有限公司 Automatic pump
FR2950941A1 (en) * 2009-10-05 2011-04-08 Arbatax DOUBLE ELECTRIC PUMP FOR THE MAINTENANCE OF SWIMMING POOLS
WO2011042646A1 (en) * 2009-10-05 2011-04-14 Arbatax Double cylinder electric pump for pool maintenance
AT521729A3 (en) * 2018-10-11 2020-09-15 Albert Ziegler Gmbh Pump device
AT521729B1 (en) * 2018-10-11 2022-01-15 Albert Ziegler Gmbh pump device

Also Published As

Publication number Publication date
GB2135022B (en) 1986-05-21
GB8303966D0 (en) 1983-03-16

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Date Code Title Description
PCNP Patent ceased through non-payment of renewal fee

Effective date: 19950214