US 3324922 A
Description (OCR text may contain errors)
'Fue! lnpm From June 1957 J. HARGREAVES EITAL 3,324,922
LIQUID FUEL FLOW CONTROL AND METERING APPARATUS Filed June 10, 1964 2 Sheets-Sheet l Fuel Flow To Boiiea' Pressurized Mains Fig.7
PAT EMT ATTORNEY June 13,, 1957 J HARGREAVES ETAL LIQUID FUEL FLOW (jONTROL AND METERING APPARATUS Filed June 10, 1964 BUILDING UNITS EUELDENG UNITS CONTROL UNET 2 Sheets-$heet 2 JOHN HARGREAVES GOQDON INKER ROYSTON GEORGE SAVER BY "Ema T QJZW PATENT ATTORNEY INVENTORS United States Patent 3,324,922 LIQUED FUEL FLOW (IONTROL AND METERING APPARATUS John Hargreaves, Eversley Centre, Gordon Inker, Church Qrookham, and Royston George Sayer, Wilmslow, England, assignors to Essa Research and Engineering Comparty, a corporation of Delaware Filed June 10, 1964, Ser. No. 374,206 6 Claims. (Cl. 15836.3)
This invention relates to a means, whereby liquid fuel from a central supply may be piped as required to a number of separate burners situated at varying distances from the central supply, in a safe and effective manner, and also whereby the fuel consumed by each particular burner is recorded on a meter.
Heretofore the piping of liquid fuel from an external source to burners in separate dwellings has presented a number of problems including those of accurate metering, the maintenance of adequate fuel pressure and the provision of satisfactory safety precautions.
It has been proposed to pipe liquid fuel, for heating, to separate units from a central location at which a central storage supply tank would be sited in an elevated position so that the fuel would flow by gravity to each of the separate units. Not only would it be costly to locate these tanks in an elevated position but they would be unsightly and detract from the appearance of the area particularly Where the units to be supplied are in residences. Furthermore, the safe and eflective supply of liquid fuel, by this method, would not always be satisfactory. In addition, this method would be limited by the contour of the area since a sufliciently elevatedposition would have to be found for the central storage supply tank and all the units supplied by it would need to be at a lower level than the storage tank. A further objection would be the fact that the available elevated site could entail problems of access by tankers for the replenishment of the fuel tank or of pumping fuel from tankers to the storage tank.
It has now been found that liquid fuel may be piped under pressure from a central supply to a number of burners situated at varying distances from it, in a safe and effective manner, and that the central supply may be located at any convenient position, irrespective of the geographical contour of the area.
According to the present invention liquid fuel is piped under superatmospheric pressure from a central fuel supply to burners installed in separate buildings in an area. The fuel arrives at each separate site under pressure and its pressure is reduced at the site to the operating pressure of the burner when it flows to the burner tank. The burner tank is provided with liquid flow control means, suitably a float operated valve, so that fuel is delivered to it only in replenishment of the fuel used by the burner, the amount of fuel used being recorded on a meter. In preferred forms of the invention safety means are provided to cut off the supply of fuel should a hazard arise such as breakage of a fuel pipe. It is preferred to select essential operating equipment, such as a liquid fuel consumption recording meter, a pressure reducing valve and, desirably, a small header tank, that can be assembled in a compact control box and to attach such equipment to a readily removable plate or panel of the control box whereby this equipment may be readily removed for servicing or repair and quickly replaced with a substitute unit. This involves a minimum of delay in restoring an interrupted service to the user. The control box may be conveniently located on or in an external wall of the site and may be provided with a viewing window for reading the meter. This enables the control box to be serviced, and the meter to be read, Without disturbing the occupants "ice of the building. It will be apparent that a feed shut-o1 device should be placed in the fuel line in advance 6 the control box so that the fuel supply may be shut-o1 from the site when required.
The invention provides a safe, effective and flexibl method of supplying liquid fuel which is readily applica ble to a wide range of conditions and installations. l is not restricted by the geographical contour of the area as in the gravity system, and is adapted to supply burner sited both above and below the central supply tank Furthermore, the system permits a much wider area tr be supplied than, for example, in a gravity feed system The invention thus provides a means of piping liquir fuels for heating purposes, as a community service, tr burners located in a number of separate buildings and t( separate burners in units, such as flats or apartments Within one or more buildings. An example of the applica tion of the invention is for the supply of fuel oil, tr
' provide hot water and central heating, to a number 01 houses located in an area such as a housing estate.
In a typical method of operation of the invention fueI oil is pumped from a central supply tank under a sufficient pressure to supply the respective burners in the system irrespective of whether, by reason of the geographical contour of the area, they are sited above or below the central supply; for example, the fuel oil may be pumped from the supply source at a pressure of 25 p.s.i.g. and may arrive at the highest sites at a pressure of, e.g., 10 p.s.i.g. and at the lowest sites at, e.g., 40 p.s.i.g. The individual pressure reducing valves at each site will be adjusted to reduce the pressure suitably and the fuel will be delivered to the burner at the appropriate burner operating pressure. A suitable operating pressure is 1 /2 p.s.i.g. which may be obtained by providing a vertical fall of, for example, 5 feet between a header tank and the burner tank or, in the absence of a header tank, between the flow line from the pressure reducing valve and the burner tank.
Apparatus suitable for carrying out the method of the invention comprises, adapted to be interposed between the central fuel supply and each burner unit, in the liquid fuel flow line, in combination, a flowmeter capable of recording and visibly registering the amount of fuel flow through the apparatus, and hence the amount of fuel consumed by the associated burner, pressure reducing means adapted to reduce the incoming fuel pressure to that required for correct operation of the burner controls, and a pressure cut-off valve adapted to isolate the fuel supply if the pressure reducingmeans fails to control the oil pressure within the specified limits. The apparatus preferably includes, additionally, a fuel flow restriction device calibrated to restrict the flow of fuel through the apparatus to a quantity that need by only slightly in excess of the maximum burner consumption, and one or more air bleeding valves in the fuel line. It also desirably includes a fuel filter and a fuel head breaker. This latter may be a fuel delivery controlled, e.g. float controlled, gravity feed fuel tank interposed between the pressure cut-off means and the burner; the employment of this integer prevents fuel pump pressure being applied directly to the burner should the pressure reducing means and fuel cut-off means both fail and thus acts as an additional safeguard. It will be understood that the burner itself is provided with a fuel tank adapted to hold a small amount of liquid fuel; a suitable and conventional fuel flow control means for this tank is a float control, e.g. a ball, valve. The pressure reducing and metering apparatus of the invention is preferably selected to be conveniently assembled in a single compact control box with a readily removable plate upon which the revelant control integers may be mounted; this allows ready installation and servicing. For example, for servicing, the entire unit attached to its backing plate may )e removed and a replacement unit installed on the spot vithin a shorttime.
Referring now to the drawings, FIGURE 1 illustrates ipparatus assembled on the removable panel of the conrol box suitable for use in a building unit, and FIGURE 2 illustrates a fuel system serving a plurality of such buildn g units.
In the drawing 1 is an air bleed valve which allows purging of the incoming fuel line. 2 is a fuel filter. 3 is a fuel restriction orifice; this is an optional safety device which may be calibrated to restrict the flow of fuel through :he apparatus to a quantity only slightly in excess of the maximum burner consumption so that, if failure, for example by fracture, occurs in any component in the fuel line, fuel spillage is reduced to a minimum. 4 is a meter to record fuel fiow. 5 is a pressure reducing valve to reduce the pressure under which the incoming fuel is supplied to that required for correct operation of the burner controls. Typically the pressure would be reduced to about atmospheric and eventually fed to the burner under a head of from about two to ten feet. 6 is a pressure cutoff valve. This is a safety device adapted to isolate the fuel supply if the reducing valve 5 fails to control within specified limits. The cut-off valve 6 may be arranged to function only if re-set manually.
7 is an air-bleed valve with which may be combined a pressure gauge. 8 is a fuel head breaker; this may be a small float controlled tank that permits gravity feed to the burner and ensures that pump pressure is not applied directly to the burner. The units 2, 4, 5, 6 and 8 are, in themselves, separately of known character, and, in a preferred form of the invention, they are mounted on a plate 9 which forms part of, and is removable from, an enclosing box 10. An isolating valve 11 is placed in the fuel supply line 12 in advance on the control box 10.
The apparatus of the invention may be conveniently located externally of the building containing the burner and other heating equipment, for example upon, or in a recess of, an external wall. This, not only adds a further safety precaution but also enables the meter to be read without the necessity for the meter reader to enter the building. The control box, containing the apparatus of the invention, may be locked to permit unauthorized tampering with the apparatus and the meter dial may be made available for inspection by the provision of a suitable window formed of a transparent material.
In the operation of the invention, as shown in the drawing, liquid fuel from a central supply source (not shown) is pumped under superatmospheric pressure by pipeline to each individual building attached to the fuel supply service. The fuel arrives at the control box and, as fuel is admitted to the burned through its associated float operated tank (not shown) it flows through the control box 10 to the burner tank passing, in sequence, through the filter 2, and fuel restriction orifice 3, to the meter 4, where the amount of fuel that flows to the burner tank is recorded and then to the pressure reducing valve 5. The fuel leaves the pressure reducing valve 5 at substantially atmospheric pressure and flows through the cutoff valve 6, which is normally in the open position, by way of the air bleed valve 7 to the header tank 8 from which it passes, through a descending pipe (not shown), to the burner tank. If a fault develops in the system a change of pressure will result and this will cause the cutoff valve valve 6 to operate to stop the flow of fuel to the tank 8 and thence to the burner tank. If, for some reason, the cut-off valve 6 fails to operate, the fiow of fuel from the header tank 8 to the burner tank will be limited by the fuel control valve in the tank 8, to the amount of fuel required to replinish the burner tank. When it is desired to service the installation the flow of fuel from the central supply is stopped simply by moving the isolating valve 11 to the closed position.
What we claim is:
1. A central liquid fuel supply system under superat-mospheric pressure supplying liquid fuel from a common source to a number of burners located in separate building units comprising, in combination, a removable panel u on which panel is mounted means to record the amount of fuel that flows to the burner associated with each unit and means to reduce the pressure of the incoming fuel substantially to the fuel operating pressure of said burner, said panel being adapted to be interposed between the common supply source and the individual burners associated with the individual building units.
2. A central liquid fuel supply system according to claim 1 comprising fuel filtering means mounted on the removable panel.
3. A central liquid fuel supply system according to claim 1 comprising means to control the flow of fuel at the burner operating pressure responsive to the fuel consumption of the burner mounted on the removable panel.
4. A central liquid fuel supply system according to claim 1 comprising means to stop the fiow of fuel if the pressure reducing means fails to control the flow of fuel within specified limits mounted on the removable panel.
5. A central liquid fuel supply system under superatmospheric pressure supplying liquid fuel from a common source to a number of burners located in separate building units comprising a pipeline supply from the common supply source, a valve in such pipeline to stop and start the fuel supply from the main fuel line, an air bleed valve which allows purging of the incoming fuel line, a fuel filter, a fuel restriction orifice to restrict the flow of fuel through the apparatus to a quantity only slightly in excess of the maximum burner consumption, a fiowmeter capable of recording and visibly registering the amount of fuel flow through the apparatus, a pressure reducing valve adapted to reduce the incoming fuel pressure substantially to the operating pressure of the burner, a shut-off valve to stop the flow of fuel if the pressure reducing valve fails to control the flow of fuel within specified limits, an air bleed valve which may be combined with a pressure gage, and a float controlled, gravity feed fuel tank to control the flow of fuel at the burner operating pressure to the fuel consumption of the burner.
6. A central liquid fiiel supply system as claimed in claim 5 comprising a removable plate upon which is mounted the system consisting of the air bleed valves, filter, orifice, fuel meter, pressure reducing valve, shutoff valve and fuel tank as described in said claim 5.
References Cited UNITED STATES PATENTS 322,002 7/1885 Phillips et al 137-613 X 2,467,357 4/ 1949 Joesting. 2,717,032 9/1955 Dupin 158-132 2,731,026 1/1956 Hughes 137-461 X 3,094,162 6/ 1963 Davies. 3,156,290 11/1964 Goodall et a1.
FOREIGN PATENTS 1,119,190 4/1956 France. 1,248,200 10/ 1960 France.
FREDERICK KETTERER, Primary Examiner.