Classifications

• • A—HUMAN NECESSITIES
  • A62—LIFE-SAVING; FIRE-FIGHTING
  • A62C—FIRE-FIGHTING
  • A62C35/00—Permanently-installed equipment
  • A62C35/02—Permanently-installed equipment with containers for delivering the extinguishing substance
  • A62C35/026—Permanently-installed equipment with containers for delivering the extinguishing substance the extinguishing material being put under pressure by means other than pressure gas, e.g. pumps
• • A—HUMAN NECESSITIES
  • A62—LIFE-SAVING; FIRE-FIGHTING
  • A62C—FIRE-FIGHTING
  • A62C35/00—Permanently-installed equipment
  • A62C35/58—Pipe-line systems
  • A62C35/60—Pipe-line systems wet, i.e. containing extinguishing material even when not in use
• • A—HUMAN NECESSITIES
  • A62—LIFE-SAVING; FIRE-FIGHTING
  • A62C—FIRE-FIGHTING
  • A62C37/00—Control of fire-fighting equipment
  • A62C37/36—Control of fire-fighting equipment an actuating signal being generated by a sensor separate from an outlet device
  • A62C37/38—Control of fire-fighting equipment an actuating signal being generated by a sensor separate from an outlet device by both sensor and actuator, e.g. valve, being in the danger zone
  • A62C37/40—Control of fire-fighting equipment an actuating signal being generated by a sensor separate from an outlet device by both sensor and actuator, e.g. valve, being in the danger zone with electric connection between sensor and actuator
• • A—HUMAN NECESSITIES
  • A62—LIFE-SAVING; FIRE-FIGHTING
  • A62C—FIRE-FIGHTING
  • A62C99/00—Subject matter not provided for in other groups of this subclass
  • A62C99/0009—Methods of extinguishing or preventing the spread of fire by cooling down or suffocating the flames
  • A62C99/0072—Methods of extinguishing or preventing the spread of fire by cooling down or suffocating the flames using sprayed or atomised water

Definitions

• the invention refers to a method for operating a sprinkler installation for fighting fire and which comprises an alarm device, a plurality of spray heads provided with thermal fuse elements, a pump device comprising at least one sprinkler pump which is adapted to discharge, upon a signal from the alarm device, water in a volume and with a pressure which are needed for the function of the sprinkler device, and a tubing (piping) system connecting the the pump device with the spray heads.
• spray head is in the present specification and in the annexed claims understood a means for discharging water in the form of jets or fog.
• thermal fuse element is understood a means which triggers the respective sprinkler head when a predetermined elevated temperature is reached; it is generally a glass bulb which bursts by heat.
• the invention refers also to a device for executing the method.
• the pump device besides of the sprinkler pump a pressure stabil ⁇ izing pump having only a small capacity (discharging a smaller flow than what is necessary for a single spray head) and delivering a maximum pressure (e.g. 6 to 7 bars) which lays only slightly above the stand-by pressure.
• the pressure stabili ing pump is driven by a pressostat and is constantly switched on.
• the sprinkler pump and the tubing system with its pipe flanges etc. are designed for a maximum pressure in the order of 10 bars, which is the conventional operational pressure of the system.
• the pressure in the tubing system decreases rapidly and the sprinkler pump is automatically started to provide the whole sprinkler installation with water for extinguishing the fire.
• the pressure (10 bars) of the water delivered to the spray heads of smaller importance than what a sufficient flow is, because from each spray head are 60 to 180 litres ejected each minute.
• the tubing system must have a suf ⁇ ficiently large diameter for such a flow.
• the starting up of the sprinkler pump is however somewhat delayed (e.g. appr. 40 to 50 seconds) , which is obviously a serious drawback.
• the reason for the delay is that the alarm valve, which operates as a check valve between the holder of the sprinkler and the sprinkler pump, needs appr. 40 second to lift, i.e. to give alarm, and then it takes appr. 10 seconds for the automat..cs (Y-D start) to generate full pressure in the pump.
• high pressure pump being there understood a pump which can deliver a pressure 10 to 2 ⁇ times higher than what the pressure in a conventional sprinkler pump is, i.e. a pressure in the order of magnitude of 100 to 200 bars.
• the high pressure pump with regulated rotation speed delivers only the volume of water which is instantly consumed, i.e. discharged by the spray heads, without the necessity of ever to return any quantity of water to the pump. This is different from pumps with unvariable capacity, in which discharged water which is not consumed is recycled ("by-passed) to the pump, with the result that spill heat is generated.
• Sprinkling begins even in such a case only if and when the glass bulbs have burst hy heat.
• a signal is sent to the control member of the pump ("the control box") to increase the pressure to the operational value. If the connection (line) between the fire centre and the control member of the pump is severed, a signal is also sent to the control member of the pump by an activated relay in the control box being dropped which is fed externally (i.e. not from the source of current feeding the alarm system) . This occurs even at a normal fire alarm. The circuit is fed by the relay voltage.
• pressure is increased to the operatoional value as soon as a glass bulb bursted, i.e. as soon as a flow comes about, which is sensed by a flow sensor in the out-line of the pump, or is measured on the armature voltage of the motor of the pump.
• the pump device comprises besides of the sprinkler pump, which operates as a mother pump, one or several (e.g. 8) slave or additional pumps which are drivable with constant speed and which, once started, operate at full effect.
• the purpose of the additional pumps is to increase the water capacity while the mother pump, reduced e.g. to 25% of its performance, continues as before to control the pressure and the flow until the additional pump or pumps no longer are needed. Then the additional pump or pumps are stopped and only the mother pump continues to operate, if needed even at its full capacity.
• the high pressure pump is embodied by a pump driven by a thyristor-controlled D.C.-motor.
• a high pressure pump 1 is driven by a thyristor- controlled D.C.-motor 20 with variable speed and is fed from a mains water line 18 by way of a water filter 6, a (pressure ⁇ free) break tank 7 and in-line 18a.
• an out-line 17 which is embodied by a high pressure conduit, and in which a flow sensor 3 sensing the flow, and a transducer 4, sensing the pressure, are arranged, is pump 1 connected to a plurality of fog spray heads 13 which are provided with heat sensitive triggers known per se, such as glass bulbs.
• the pressure in the out-line 17 is indicated on a display instrument 5.
• a closing valve 11 and a run-off valve 12 for the fog sprinkling water provided in the line 17, more correctly in a branching 17 'thereof, leading to the fog spray heads 13, is a closing valve 11 and a run-off valve 12 for the fog sprinkling water provided.
• additional pumps 2 provided which are driven by A.C.motors 21 and which through a line 18b are fed with water from the main line 18, more correctly from the break tank 7.
• the out-lines of the additional pumps 17a are connected to the line 17 via the main or mother pump 1.
• the electrical motors 1 nad 2 are through electric lines 20a and 21a fed with current from a central control means (control box) 8 to which feeder current is brought via a line 15.
• the flow and pressure values, sensed by the sensors 3 and 4 are fed into the control box 8 through lines 3a and 4a, and via a line 14a is information about the water level in the reak tank 7, in which a level sensor 14 is provided to this purpose, fed into the box 8.
• the control box 8 are further provided, among other things, two rotary potentiome ⁇ ters 4", 4" for setting the two pressure values (stand-by pressur and operational pressure) , and a thyristor bridge 20b for controlling the motor 20.
• a fire alarm centre 9 is by an alarm line 16 connected with (smoke or heat sensitive) fire detectors (not shown) which are distributed in the space which shall be monitored, and by a line 9a is the fire centre 9 connected to the control box 8.
• the closing valve 11 is by a line 11a connected to a programable logical system (PLS) 10 for the control of valves, which system is in its turn via a line 10a connected the fire alarm centre 9.
• PLS programable logical system
• PLS can be programmed so as to upon a fire open a closed valve (e.g. valve 11) in the section in which the valve is located, or a closed valve which controls the flow to a large space (e.g, a restaurant) where everthing shall be fog- sprinkled at the same time (so called "deluge”) .
• a closed valve e.g. valve 11
• a closed valve which controls the flow to a large space e.g, a restaurant
• valve is then closed either manually or by the PLS 10 being programmed after some time (e.g. 4 minutes) again to close the previously opened valve.
• some time e.g. 4 minutes
• the installation operates in the following manner.
• the high pressure pump 1 is continously driven by the motor 20 with a speed which results in the line 17 in pressure of e.g. 10 bars, the stand-by pressure of the sprinkler installation, and the valve 11 is open.
• the motors 21 and the pumps 2 are at rest.
• the additional pump are thus consecutively started one after the other, the second after the mother pump after the the start of the first one again has reached the predetermined part of its maximim capacity, etc., etc.
• the mother pump regulates now the rotation speed of the whole system so that correct pressure and flow is achieved, and to the spray heads 13 flows water as well from the mother pump 1 through the line 17, as from the additional pumps 2.
• the fire alarm from the detectors may not be coupled to the mother pump 1
• this pump is activated when, and by the fact that the thermal fuse element (glass tube) in any of the spray heads is destroyed.
• the first water which then comes out from the spray head has only stand-by pressure, i.e. 10 bars for instance, but as soon as a fl >w comes about in the line 17 and is sensed by the flow sensor '. , a signal is generated to increase the rotation speed of the motor 20 so that the pressure increases to its operational value, e.g. 100 bars.
• the purpose of the at least one additional pump 2 which goes for full after having ben started is to increase the water capacity.
• the flow and the pressure in the line 17 continue to be regulated, as before, by the mother pump 1 (reduced to 25% performance) until the additional pump or pumps 2 r.o longer are needed, as mentioned before. Then it or they are stopped and only the mother pump 1 operates.
• the additional pump or pumps may also be used as spare pumps and be individually started, thus increasing the fire security.

Landscapes

• Health & Medical Sciences (AREA)
• Public Health (AREA)
• Business, Economics & Management (AREA)
• Emergency Management (AREA)
• Fire-Extinguishing By Fire Departments, And Fire-Extinguishing Equipment And Control Thereof (AREA)
• Control Of Positive-Displacement Pumps (AREA)
• Spray Control Apparatus (AREA)

Applications Claiming Priority (3)

Publications (1)

Family

ID=20389792

Family Applications (1)

Country Status (6)

Families Citing this family (12)

Family Cites Families (2)

• 1993
  • 1993-04-30 SE SE9301490A patent/SE501398C2/sv unknown
• 1994
  • 1994-04-13 JP JP07477594A patent/JP3335469B2/ja not_active Expired - Lifetime
  • 1994-04-18 TW TW083103414A patent/TW309437B/zh active
  • 1994-04-25 WO PCT/SE1994/000366 patent/WO1994025113A1/en not_active Application Discontinuation
  • 1994-04-25 AU AU65478/94A patent/AU6547894A/en not_active Abandoned
  • 1994-04-25 EP EP94913247A patent/EP0696218A1/en not_active Withdrawn

Non-Patent Citations (1)

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