SE501398C2 - Method of operating a sprinkler system and apparatus for carrying out the procedure - Google Patents

Abstract

A pump device for feeding a sprinkler system comprises a speed controlled, D.C. driven mother pump (1) which continuously maintains a stand-by pressure in the sprinkler system, and at least one slave pump (2) which is switched on when, after alarm has been given, the performance of the mother pump in maintaining the stand-by pressure has reached a predetermined part of its maximum value. The performance of the mother pump is then reduced to a predetermined lower level, and the slave pump or pumps are stopped when no more needed.

Description

501 398 2 When one or more of the sprinkler heads is triggered after the respective glass bulb has passed, the pressure in the pipeline system drops rapidly, and the sprinkler pump is started automatically to supply the entire sprinkler system with water for extinguishing. In this case, the pressure (10 bar) in the water supplied to the sprinkler heads is less important than sufficient flow, since 60-180 1 / min radiates from each sprinkler head. The pipe system must have a sufficiently large diameter for such flows.

However, the start-up of the sprinkler pump is delayed somewhat (eg by about 40-50 seconds), which is obviously a serious disadvantage. The reason for the delay is that the alarm valve acting as a non-return valve between the sprinkler holder and the sprinkler pump takes about 40 seconds to lift, ie give an alarm, and then it takes about 10 seconds for the automation (Y-D start) to achieve full pressure at the pump.

The object of the present invention is to provide a method and a device in which the pressure holding pump can be switched off, the pipe system can have a smaller diameter, and the delay at start-up is eliminated.

According to the invention, this task is solved in the manner set out in closely related claims, wherein by "high-pressure pump" is meant a pump which can give 10-20 times higher pressure than a conventional sprinkler pump, ie a pressure of the order of 100-200 bar.

According to the invention, the speed-controlled high-pressure pump delivers only the amount of water that is currently consumed, ie is taken out of the sprinkler heads, without any amount of water ever having to be returned to the pump. This is in contrast to pumps with immutable capacity, where the water that is delivered but not discharged goes back into the pump ("by-pass"), causing loss of heat to be generated.

However, a high-pressure pump has the disadvantage when starting up in a non-, or not completely, water-filled pipe system that the air present in the pipe system is then compressed when violent pressure shocks occur ("hammer blow effect") which can cause the entire pipe system to be shaken down after a sf '501 398 3 tag. Because the pipe system according to the invention is kept constantly air-free and filled with water with the emergency pressure, eg 10 bar, no pressure surges occur when the pressure is raised to the operating pressure value between 100 and 200 bar.

Thus, there is water in the sprinkler heads with the high operating pressure as soon as the alarm has gone off, but it is held back by the glass bulbs, so that sprinkling starts only when these have cracked due to the heat effect.

This means that no sprinkling takes place in the event of a false alarm, ie when an (eg triggered by smoke) alarm signal is not accompanied by the development of heat. The operating pressure or the increased speed can be reset manually.

Preferably, the measure is further programmed (programmed) that the speed of the pump and thereby also the water pressure is increased to the higher values even when the alarm system is out of order for some reason, as this may be due to a circumstance that entails a fire hazard. Even in this case, the sprinkling itself starts, of course, only if, and when, the glass bulbs have burst from the heat.

When a signal is received in the fire alarm control panel indicating that a detector has been removed or is inoperable, a signal is sent to the pump control unit ("control cabinet") to increase the pressure to the operating pressure value. If the connection (line) between the fire control panel and the pump control unit is interrupted, a signal is also given to the pump control unit by releasing an external supply (ie not from the alarm system's power supply), the drawn relay therein. This also happens with a normal fire alarm. The circuit is supplied with the relay voltage.

If all these signals should not be present, the pressure is increased to the operating pressure value as soon as a glass bulb has burst, ie as soon as a flow occurs, which is sensed via a flow monitor at the pump's output line or measured at the pump motor's armature voltage.

In a preferred embodiment of the invention, the pump device in addition to the sprinkler pump operating as a parent pump comprises one or more (eg 8) with constant speed drivable slave or auxiliary pumps which run at full speed once they have been started. The purpose of the auxiliary pumps is to increase the water capacity, while the mother pump, which is reduced to 25% performance, for example, continues to control pressure and flow as before until the auxiliary pump or pumps are no longer needed. Then the auxiliary pump or pumps are stopped and only the mother pump continues to operate, where applicable up to its full capacity.

While a high-pressure pump with adjustable speed can in principle also be used with a unit consisting of a motor rotating at an unchanged speed plus a separate speed regulator, the high-pressure pump in a preferred embodiment of the invention consists of a pump driven by a thyristor-controlled DC motor. .

The invention will now be explained in more detail with the aid of an exemplary embodiment according to the accompanying drawing, which is a diagram in which water pipes are made of double lines, and electrical lines of single lines.

A high-pressure pump 1 is driven by a thyristor-controlled, speed-controlled DC motor 20 and is fed from a main water line 18 via a water filter 6, a (pressureless) break tank 7 and an inlet line 18a.

Via an outlet line 17, which is designed as a high-pressure line, and in which a flow monitor 3 which senses the flow, and a transducer 4, which senses the pressure, are connected, the pump 1 is connected to a plurality of mist sprinkler heads 13 which are equipped with per se known heat-sensitive triggers such as glass bulbs. The pressure in the outlet line 17 is indicated by an indicator instrument 5.

Furthermore, in the line 17, respectively in its branch 17 'leading to the mist sprinkler heads 13, a shut-off valve 11 and a drain valve 12 for mist sprinkler water are connected.

In addition to the pump 1, there are a plurality (in practice, for example, 8) of additional pumps 2 driven by AC motors 21, which are supplied with water from the main line 18 and 18, respectively, via an input line 18b. the break tank 7. The output lines 17a of the additional pumps 2 are connected to the line 17 via the main and main pump 1. 501 398 and the main pump 1, respectively.

The electric motors 1 and 2 are supplied with current via power lines 20a and 21a from a central control unit (control cabinet) 8, where the supply current is supplied via a line 15. In the control cabinet 8 the flow and pressure values occupied by the sensors 3 and 4 are input, and via a line 14a the information on the water level in the break tank 7, for which purpose a level meter 14 is built in. Furthermore, in the control cabinet 8, among other things, two rotary potentiometers 4b ', 4b "for setting the two pressure values (standby pressure and operating pressure), and a thyristor bridge 20b for controlling the motor 20 are arranged.

A fire alarm control panel 9 is connected via an alarm line 16 to non-shown (smoke and or heat sensitive) fire detectors, which are located in the monitored space, and via a line 9a, the fire alarm control panel 9 is connected to the control cabinet 8.? The shut-off valve 11 is connected via a line 11a to a programmable logic system (PLS) 10 for valve control, which in turn is connected via a line 10a to the fire alarm control panel 9.

PLS 10 is programmed to open a closed valve (eg valve 11) in case of fire within the section where the valve is located, or a closed valve that controls the inflow to a large space (eg a restaurant) where everything is to be mist-sprinkled at the same time (so-called "deluge").

When the firefighters arrive, they take care of the extinguishing with their own tools and sprinkling is no longer needed or desired. The valve is then closed again either manually or by PLC 10 being programmed to close the valve that was opened before that after a certain time interval (eg 4 minutes). When the valve is closed, the flow is reduced and the auxiliary pump or pumps are no longer needed.

The plant works in the following way. The high-pressure pump 1 is continuously driven by the motor 20 at a speed which results in a pressure in the line 17 of, for example, 10 bar, which constitutes the emergency pressure of the sprinkler system, and the valve 11 is open. The motors 21 and the pumps 2 are at rest. 501 398 6 When a fire alarm is received via line 16, this alarm signal is received by an interface in the control cabinet 8 and by the thyristor bridge 20b the speed of the mother pump is controlled so that the pressure in the pipeline system is increased to a predetermined operating pressure value, eg 100 bar, while flow is allowed vary.

This pressure spreads rapidly all the way to the mist sprinkler heads 13, which, however, do not start working until their heat protection elements have been affected, ie the glass bulbs have cracked. Thus, when this happens, the high pressure is already "in place" in the mist sprinkler heads.

When the pressure monitor 3 continuously "reports" to the control cabinet 8 that the pressure in the line 17 has a lower value than the pre-selected operating pressure value set on one of the rotary potentiometers 4b ', 4b "(eg 100 bar), the speed of the mother pump 1 is increased until the operating pressure value again, or, if the mother pump has reached a predetermined part of its maximum performance (eg 75% thereof), a signal is generated in the control cabinet 8 that a first of the auxiliary pumps 2 is to start, and at the same time a signal is given to the motor 20 to pull down the speed to a preselected reduced value (corresponding to eg 25% of the mother pump's 1 maximum performance).

If the mother pump 1 with the first auxiliary pump 2 starts again when the first mentioned predetermined performance value (eg 75%), the auxiliary pump number two is started and at the same time a signal is given to the mother pump 1 to go down again to the reduced second preselected value (eg 25% of maximum performance).

This procedure is repeated as needed, until all additional pumps are connected, if necessary. These additional pumps are thus started in succession, the second when the mother pump, after starting the first one, has again reached the predetermined part of its maximum capacity, and so on and so forth.

The mother pump now speed regulates the entire system to the correct pressure and flow, and through the line 17 water flows to the sprinkler heads 13 both from the mother pump 1 and from the auxiliary pumps 2.

If the fire alarm from the detectors for any reason must not be connected to the mother pump 1, this is activated when v 501 398 and by the heat fuse element (glass bulb) on one of the sprinkler heads yielding. The first water, which then comes out of the sprinkler head, has only the standby pressure, i.e. for example 10 bar, but as soon as a flow is produced in the line 17 and sensed by the flow monitor 3, the signal is generated to increase the engine 20 speed so that the pressure rises to its operating value, for example 100 bar.

The purpose of the at least one additional pump 2 after the service is fully running is to increase the water capacity.

The flow and pressure in the line 17 continue to be controlled as before by the (pump reduced at, for example, 25% performance) the mother pump 1 until the auxiliary pump or pumps 2 are no longer needed, as stated above. Then the one or these are stopped and only the mother pump 1 continues to operate.

The advantage of using one or more (8 pieces, eg fi non-speed-controlled, alternating current and direct-starting auxiliary pumps connected to a speed-controlled mother pump is the low price of available pump capacity and simple and economical storage of spare parts.

The auxiliary pump or pumps can also be used as spare pumps and started individually, which increases fire safety.

Claims (16)

8 Patent claims A method of operating a fire-fighting sprinkler system comprising an alarm device, a plurality of heat-insulating sprinkler heads, a pump device controlled by a control means, and a piping system connecting the pump device to the sprinkler heads, the pump device comprising at least one electric motor pump and in the standby state keep the piping system filled with water with a lower standby pressure and when an alarm signal generated in the alarm device generates water in the piping system to supply water required for the sprinkler head extinguishing function and higher operating pressure, characterized in that in the pump device a sprinkler pressure is installed with adjustable speed, so that by changing the speed the amount and / or the pressure of the water discharged into the pipe system changes, that the pump device is normally operated at a first, lower speed in order to act as a pressure holding pump at a lower maintaining the pressure in the piping system maintain this pressure at its preselected value, and that at the creation of said alarm signal it is operated at a higher speed to provide the water flow in the piping system for the extinguishing function of the sprinkler system and / or the higher operating pressure, e.g. 200 bar, for this purpose. Method according to claim 1, characterized in that the sprinkler heads are made fully functional immediately after the release by raising the pressure in the pipeline system to the operating pressure value via said speed increase even before the thermal fuse elements have broken. Method according to claim 1 or 2, characterized in that in the pipe system a flow and / or pressure sensor connected to the control means of the pump device is arranged and that the pump device further comprises at least one additional pump drivable at unchanged speed which is started automatically when the mother pump of flow and / or the capacity of the pressure sensor is utilized to a preselected part of the maximum value, whereby at the same time the capacity of the mother pump is reduced by reducing the speed d to a preselected smaller part of the maximum value. Method according to claim 3, characterized in that in the presence of several auxiliary pumps these are started in a successive manner in such a way that the second is started when the mother pump, after starting the first auxiliary pump, has again reached the predetermined part of its maximum capacity, etc. etc. Method according to Claim 3 or 4, characterized in that the auxiliary pump or pumps are stopped when, as a result of reduced flow requirements, they are no longer needed and the mother pump continues to operate alone, possibly with maximum capacity. Method according to one or more of the preceding claims, characterized in that the standby pressure is in the order of 10 bar, the operating pressure is in the order of 100-200 bar, and the two predetermined parts of the parent pump's maximum capacity in question are in the order of 75% and 25%. Device for operating, according to the method according to any one or more of the preceding claims, a sprinkler system intended for fire fighting which comprises an alarm device, a plurality of sprinkler heads (13) provided with heat fuse elements, a pump device controlled by a control means (8) and a pipeline system (17, 17 ') which connects the pump device to the sprinkler heads, the pump device comprising at least one electric motor-driven sprinkler pump (1) and is arranged to constantly keep the pipeline system filled with water with a lower standby pressure and when an alarm signal generated in the alarm device is output into the pipeline system water in the amount and higher operating pressure required for the extinguishing function of the sprinkler heads, characterized in that a high-pressure pump with adjustable speed is installed in the pump device and the control means is arranged to keep this speed set at a lower value in the standby state. lower emergency pressure value of the discharged water, and upon receipt of an alarm or start signal, increase the speed to a second, higher value corresponding to a preselected second higher operating pressure value of the discharged water. Device according to claim 7, characterized in that the pump device further comprises at least one variable speed drivable slave or auxiliary pump (2) with 501 398 ,,, smaller capacity, and that the control device is arranged to start the auxiliary pump or pumps when the capacity of the the sprinkler pump operating as the parent pump has reached a predetermined part of its maximum value. Device according to claim 8, characterized in that the control device is arranged to reduce the performance of the parent pump to a predetermined smaller part of the maximum value, and to stop the auxiliary pump or pumps when they are no longer needed. Device according to claims 8 and 9, characterized by rotary potential meters (4b ', 4b') for setting said two parts of the maximum capacity of the mother pump. Device according to Claim 8 or 9, characterized in that the mother pump is driven by a DC motor (20) with a variable speed and the additional pump (s) present, if any, are driven by an AC motor (21). Device according to one or more of Claims 7 to 11, characterized in that the capacity of the auxiliary pump or pumps is of the order of half that of the mother pump. Device according to one or more of Claims 7 to 12, characterized in that a pressure sensor (4) and / or flow sensor (3) is arranged in the pipeline system, the output signals of which are supplied to the control device. Device according to one or more of Claims 7 to 13, characterized by a pointing instrument (5) for indicating the pressure in the water leaving the pump device. Device according to one or more of the claims 7-14, characterized by a sensor which is arranged to set the operating pressure value when the detector and / or alarm system is out of order. Device according to one or more of Claims 7 to 15, characterized in that the sprinkler heads are mist sprinkler heads.