GB2516879A

GB2516879A - Fire suppression system

Info

Publication number: GB2516879A
Application number: GB1313890.4A
Authority: GB
Inventors: Bernard Cain
Original assignee: PROJECT FIRE PRODUCTS Ltd
Current assignee: PROJECT FIRE PRODUCTS Ltd
Priority date: 2013-08-02
Filing date: 2013-08-02
Publication date: 2015-02-11
Anticipated expiration: 2033-08-02
Also published as: GB2516879B; WO2015015227A1; EP3027284A1; GB201313890D0

Abstract

A system and method for identifying a leak in a wet fire suppression system is disclosed. The fire suppression system includes a fluid distribution device such as a sprinkler head, (16, figure 1), a fluid flow path 31 for connecting the fluid distribution device to a fluid source, a non-return, or check, valve 51 positioned in the fluid flow path, a pressure sensing device 61, 71 positioned in the fluid flow path for sensing the pressure of fluid in the flow path and for generating a signal indicative of the sensed pressure at the location, and a controller 80 for receiving the signal and for providing an indication to a user as to the location of a potential fluid leak in the flow path. The system may further comprise additional fluid flow paths connecting a fluid source with a fluid distribution device having a further non-return valve and pressure sensors. The non-return valve and pressure sensors may be integrally formed. Also disclosed is a fire suppression system including an isolation valve, discharge valve, pressure sensor and a controller operable identify a fluid leak associated with the isolation valve.

Description

Title: Fire suppression system Descrirtion of Invention This invention relates to a fire suppression system. In particular, this invention relates to a system for providing an indication to a user as to the location or likely location of a potential fluid leak in the system.

Fire suppression systems for supplying fluids (e.g. liquids, such as water) to sprinklers or hose reels typically are installed in industrial and commercial premises and in buildings of residential accommodation. The purpose of such systems is to suppress and/or contain a fire in the building, in the event that one is detected. Systems for detecting fires in buildings are well known, including temperature sensors and smoke sensor devices, and the aim of such systems is to detect the presence of a fire as early as possible, in order to activate the sprinklers or hose reels to suppress and/or contain the fire before it has a chance to spread and cause wide scale damage.

Fire suppression systems may be installed in multiple storeys of a building.

Each storey may have a large floor area, and therefore the length, and volume, of pipe work required to supply water to the plurality of sprinklers, or hose attachment point(s), may be significant. Operation of these fire suppression systems is such that the pipe work always carries pressurised water, so that in the event of a fire water can be instantly discharged from the pipe work. A problem with having pressurised water in the pipe work is that the pipe work is prone to leakages, either due to corrosion of the pipe work or components attached thereto, such as a valve, a sprinkler or a hose attachment point. In the event of a leakage, a pressure maintenance pump (commonly known as a jockey pump) is activated which pumps water into the system to restore and maintain a specified pressure. This enables the system to be operable if required. However, it does not provide any indication to a user as the likely location of a leak. This is problematic because if the leak goes undetected it has the potential to worsen and may result in false alarms or indeed the entire system having to be shutdown in order locate and fix the leak or to execute any necessary inspections tests, servicing and maintenance. It is also problematic because water is being continuously discharged from the system, which is costly.

It is an object of the invention to seek to provide an improved a fire suppression system.

It is a further object of the invention to seek to provide proactive service and maintenance data on a fire suppression system.

In one aspect of the invention, we provide a fire suppression system, including: a fluid distribution device; a fluid flow path for connecting the fluid distribution device to a fluid source; a non-return valve positioned in the fluid flow path; a pressure sensing device positioned in the fluid flow path for sensing the pressure of fluid in the flow path at a location and for generating a signal indicative of the sensed pressure at the location; and a controller for receiving the signal from the pressure sensing device and for providing an indication to a user as to the location or likely location of a potential fluid leak in the flow path.

In a second aspect of the invention, we provide a method of providing an indication to a user as to the location of a potential fluid leak in a fire suppression system, the fire suppression system including: a fluid distribution device; a fluid flow path for connecting the fluid distribution device to a fluid source; wherein the method includes: sensing the pressure of a fluid at a location in the fluid flow path; generating a signal indicative of the sensed pressure at the location; and providing an indication to a user as to the location or likely location of a potential fluid leak.

In a third aspect of the invention, we provide a building having a fire suppression system, wherein the fire suppression system includes: a fluid distribution device; a fluid flow path for connecting the fluid distribution device to a fluid source; a non-return valve positioned in the fluid flow path; a pressure sensing device positioned in the fluid flow path for sensing the pressure of fluid in the flow path at a location and for generating a signal indicative of the sensed pressure at the location; and a controller for receiving the signal from the pressure sensing device and for providing an indication to a user as to the specific location of a fluid leak in the flow path.

Preferably, the fire suppression system includes a further fluid flow path, the further fluid flow path connecting a respective fluid distribution device to the fluid source and having a non-return valve positioned therein.

Preferably, a pressure sensing device is positioned in the further fluid flow path for sensing the pressure of fluid in the further fluid flow path at a location and for generating a signal indicative of the sensed pressure at the location.

Preferably, the controller receives the signal from the pressure sensing device of the further fluid flow path and provides an indication to a user as to which fluid flow path is the likely location of the potential fluid leak.

Preferably, the pressure sensing device is positioned in a portion of the fluid flow path connecting the non-return valve to the fluid distribution device.

Preferably, the pressure sensing device is positioned in a portion of the fluid flow path connecting the fluid source to the non-return valve.

Preferably, the fire suppression includes an isolation valve positioned in the fluid flow path between the non-return valve and the fluid source.

Preferably, the indication to a user is provided in the form of a visual display or an audible alarm or a lookup table.

Preferably, the pressure sensing device and the non-return valve are formed integrally.

Alternatively, the pressure sensing device and the non-return valve are separate components.

Preferably, the fire suppression system is a wet fire suppression system.

The non-return valve may be any one of a swing check valve, a ball check valve, a diaphragm check valve, a swing check valve or any other suitable one-way valve.

The pressure sensing device may be a pressure transducer.

The method may include the step of providing an indication to a user in the form of a visual display and/or an audible alarm and/or a lookup table.

The method may include the step of providing an indication to a user in the form of a map showing the location or likely location of the potential fluid leak.

Embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, of which: Figure 1 illustrates diagrammatically part of a typical fire suppression system for a building; Figure 2 illustrates diagrammatically the layout of part of a fire suppression system in accordance with the present invention; and Figure 3 illustrates diagrammatically a one-way valve used in the system of figure 2.

Referring firstly to Figure 1 of the drawings, this shows a typical layout of part of a fire suppression system. The system includes a flow path 10 leading to five main outlet pipes 11 to 15, each of which has six fluid distribution devices connected thereto, in the form of sprinkler heads as indicated at 16 to 21 of the outlet pipe 11. It will be appreciated that a fire suppression system may in fact have more or less pipe work and/or distribution devices than those illustrated depending on the nature and size of the premises in which the system is installed.

Figure 2 shows diagrammatically part of a fire sprinkler system at which several storeys of a multi-storey building are supplied. A riser pipe 30 supplies fluid to respective flow paths 31 to 35 which, in turn, provide fluid to distribution devices (not shown) on respective storeys of the building. The fluid is typically water but other fluids may be used including gases, such as carbon dioxide.

Isolation valves 41 to 45 and one-way valves 51 to 55 are provided in respective flow paths 31 to 35. It is to be understood that each one-way valve 51 to 55 permits fluid to flow from the riser pipe 30 towards a respective distribution device but prevents fluid at a higher pressure from flowing in the opposite direction. The isolation valves 41 to 45 are open during normal operation of the system but are capable of being closed to stop fluid from flowing to a respective one-way valve 51 to 55.

Each of the flow paths 31 to 35 are alike, so only one, flow path 31, will be described in detail. A first pressure transducer 61 is provided in the one-way valve 51 on the side that receives fluid from the riser pipe 30 (Le. upstream of the one-way valve 51) and a second pressure transducer 71 is provided in the one-way valve 51 on the opposite side (Le. downstream of the one-way valve 51). As illustrated in Figure 3, the pressure transducers 61, 71 are formed integrally with the one-way valve 51. In other examples the pressure transducers 61, 71 may be separate from the one-way valve 51, so long as a pressure transducer 61, 71 is provided to detect pressure in the flow path 31 on both sides of the one-way valve 51.

When such a system is in operation the first and second pressure transducers 61, 71 sense the pressure of the fluid in the flow path 31 on either side of the one-way valve 51 at predetermined time intervals and generate respective signals indicative of the sensed pressure. The signals are delivered from the first and second pressure transducers 61, 71 to a central controller 80 via a line 91 (there could be respective communication lines for the transducers 61, 71). Signals indicative of the sensed pressure generated in flow paths 32 to are similarly delivered to the central controller 80 via respective lines 92 to (or respective communication lines for each transducer).

The controller 80 stores data generated by signals received from the lines 91- 95. If one or more of the pressure transducers 61-65; 71-75 detects a drop in pressure in a flow path 31-35 an indicator is provided to a user as to the specific location of a potential fluid leak. For instance, the user may view a screen showing a map of the building and the map may identify the specific location of a leak. In other examples, the controller 80 may generate a table of data for a user to review periodically, say every hour or a few times a day, which table of data associates leaks in the system with their specific location.

In addition to identifying the specific location of a leak, it is to be appreciated that the data may also be used to calculate the magnitude of the leak. For instance, the user (say, an engineer) may be able to derive from the data how long it took for the pressure to drop before a jockey pump 100 activated to restore pressure in the system. It may be evident from the data that the pressure dropped over a number of days before the jockey pump 100 activated, and therefore the leak may be considered relatively small (i.e. low priority). Alternatively, it may be evident that the pressure dropped over a number of hours (or even minutes or seconds) before the jockey pump 100 activated, and therefore the leak may be considered relatively big (i.e. high priority). Moreover, where more than one leak is present in the system, the engineer may be able to categorise the leaks in order of seriousness and therefore attend to the high priority leak or leaks first. It is therefore to be appreciated that the system provides a proactive mechanism by which a fire suppression system may be maintained, for example by utilising engineers in a more sustainable and cost efficient manner.

The system also provides a mechanism for validating components of the system, such as the one-way valves 51-55. For instance, take the example that there is a pressure loss detected in flow path 31 upstream of the one-way valve 51. Pressure transducer 61 will sense a reduction in the pressure, causing the jockey pump 100 to activate once the pressure has reached a predetermined low level. Assuming the one-way valve 51 is operating correctly, the transducer 71 should not detect any loss in pressure. This is because flow downstream of the one-way valve 51 is not able to flow in reverse (due to the presence of the one-way valve 51). However, should the pressure transducer 71 also detect a pressure decrease in the flow path 31, this is an indicator that the one-way valve 51 is not operating correctly, e.g. it has become jammed, and thereby permitting reverse flow. The one-way valve 51 may then be fixed or replaced.

Advantageously, it may also be possible to utilise the system to service isolation valves 41-45. For instance, a discharge valve 81-85 may be positioned in the flow path 31-35 between the isolation valve 41-45 and the non-return valve 51-55. A service engineer may first close the isolation valve 41-45 and then open the discharge valve 81-85 to drain fluid from between the isolation valve 41-45 and the non-return valve 51-55. Pressure transducer 61-generates a signal indicative of a loss in pressure at that location as a consequence of the engineer draining opening the discharge valve 81-85.

The discharge valve 81-85 may then be closed. The service engineer then monitors the system over a period of time, say up to one hour or at predetermined time intervals. If the signals generated by pressure transducer 61-65 do not indicate an increase in pressure at that location then it is clear that the isolation valve 41-45 is fit for purpose. However, if the signals generated by pressure transducer 61-65 indicate an increase in pressure at that location then it is clear that the isolation valve 41-45 is leaking and therefore not working correctly and requires fixing or replacing.

Referring back to Figure 2, the following scenarios are provided which explain how the system would operate in the event that a leak was present in the system at either location A, B or C. Leak at location A Pressure transducer 71 generates signals indicative of a pressure loss in the flow path 31 downstream of the non-return valve 51. Pressure transducers 72-generate signals indicative of no pressure loss downstream of the respective non-return valves 52-55. Pressure transducers 61-65 may detect slight losses in pressure due to the displacement of fluid from the riser pipe 30 to flow path 31. The controller 80 receives the signals and indicates to the user that there is a leak in the system downstream of the non-return valve 51.

Leak at location B Pressure transducers 71-75 generate signals indicative of no pressure loss downstream of the respective non-return valves 51-55. Pressure transducer 63 generates a signal indicative of a pressure loss in the flow path 33.

Pressure transducer 64 generates a signal indicative of a pressure loss in the flow path 34, the pressure loss being less than that detected in flow path 33.

Pressure transducer 65 generates a signal indicative of a pressure loss in the flow path 35, the pressure loss being less than that detected in flow path 34.

Due to the static pressure in the riser pipe 30 there is unlikely to be any loss in pressure detected at pressure transducers 61-62. The controller 80 receives the signals and indicates to the user that there is a leak in the system upstream of the non-return valves 51-55 and that the most likely location of the leak is in flow path 33.

Leak at location C Pressure transducer 74 generates signals indicative of a pressure loss in the flow path 34 downstream of the non-return valve 54. Pressure transducers 71- 73 and 75 generate signals indicative of no pressure loss downstream of the respective non-return valves 51-53 and 55. Pressure transducers 64-65 may detect slight losses in pressure due to the displacement of fluid from the riser pipe 30 to flow path 34. Due to the static pressure in the riser pipe 30 there is unlikely to be any loss in pressure detected at pressure transducers 61-63.

The controller 80 receives the signals and indicates to the user that there is a likely leak in the system downstream of the non-return valve 54.

When used in this specification and claims, the terms "comprises" and "comprising" and variations thereof mean that the specified features, steps or integers are included. The terms are not to be interpreted to exclude the presence of other features, steps or components.

The features disclosed in the foregoing description, or the following claims, or the accompanying drawings, expressed in their specific forms or in terms of a means for performing the disclosed function, or a method or process for attaining the disclosed result, as appropriate, may, separately, or in any combination of such features, be utilised for realising the invention in diverse forms thereof.

Claims

Claims 1. A fire suppression system, including: a fluid distribution device; a fluid flow path for connecting the fluid distribution device to a fluid source; a non-return valve positioned in the fluid flow path; a pressure sensing device positioned in the fluid flow path for sensing the pressure of fluid in the flow path at a location and for generating a signal indicative of the sensed pressure at the location; and a controller for receiving the signal from the pressure sensing device and for providing an indication to a user as to the location or likely location of a potential fluid leak in the flow path.
2. A fire suppression system according to claim 1, including a further fluid flow path, the further fluid flow path connecting a respective fluid distribution device to the fluid source and having a non-return valve positioned therein.
3. A fire suppression system according to claim 2, wherein a pressure sensing device is positioned in the further fluid flow path for sensing the pressure of fluid in the further fluid flow path at a location and for generating a signal indicative of the sensed pressure at the location.
4. A fire suppression system according to claim 3, wherein the controller receives the signal from the pressure sensing device of the further fluid flow path and provides an indication to a user as to which fluid flow path has the potential fluid leak.
5. A fire suppression system according to any one of the preceding claims, wherein the pressure sensing device is positioned in a portion of the fluid flow path connecting the non-return valve to the fluid distribution device.
6. A fire suppression system according to any one of the preceding claims, wherein the pressure sensing device is positioned in a portion of the fluid flow path connecting the fluid source to the non-return valve.
7. A fire suppression system according to any one of the preceding claims, further including an isolation valve positioned in the fluid flow path between the non-return valve and the fluid source.
8. A fire suppression system according to any one of the preceding claims, wherein the indication to a user is provided in the form of a visual display or an audible alarm or a lookup table.
9. A fire suppression system according to any one of the preceding claims, wherein the pressure sensing device and the non-return valve are formed integrally.
10. A fire suppression system according to any one of claims 1 to 8, wherein the pressure sensing device and the non-return valve are separate components.
11. A fire suppression system according to any one of the preceding claims, wherein the fire suppression system is a wet fire suppression system.
12. A fire suppression system according to any one of the preceding claims, wherein the non-return valve is any one of a swing check valve, a ball check valve, a diaphragm check valve, a swing check valve or any other suitable one-way valve.
13. A fire suppression system according to any one of the preceding claims, wherein the pressure sensing device is a pressure transducer.
14. A method of providing an indication to a user as to the location of a potential fluid leak in a fire suppression system, the fire suppression system including: a fluid distribution device; a fluid flow path for connecting the fluid distribution device to a fluid source; wherein the method includes: sensing the pressure of a fluid at a location in the fluid flow path; generating a signal indicative of the sensed pressure at the location; and providing an indication to a user as to the location or likely location of a potential fluid leak.
15. A method according to claim 14 including the step of providing an indication to a user in the form of a visual display and/or an audible alarm and/or a lookup table.
16. A method according to claim 14 or claim 15 including the step of providing an indication to a user in the form of a map showing the location or likely location of the potential fluid leak.
17. A building having a fire suppression system, wherein the fire suppression system includes: a fluid distribution device; a fluid flow path for connecting the fluid distribution device to a fluid source; a non-return valve positioned in the fluid flow path; a pressure sensing device positioned in the fluid flow path for sensing the pressure of fluid in the flow path at a location and for generating a signal indicative of the sensed pressure at the location; and a controller for receiving the signal from the pressure sensing device and for providing an indication to a user as to the location or likely location of a potential fluid leak in the flow path.
18. Afire suppression system, including: a fluid distribution device; a fluid flow path for connecting the fluid distribution device to a fluid source; an isolation valve positioned in the fluid flow path; a discharge valve positioned in the fluid flow path between the isolation valve and the fluid distribution device; a pressure sensing device positioned in the fluid flow path for sensing the pressure of fluid in the flow path at a location and for generating a signal indicative of the sensed pressure at the location; and a controller for receiving the signal from the pressure sensing device and for providing an indication to a user of a potential fluid leak associate with the isolation valve.
19. A fire suppression system according to claim 18, wherein the pressure sensing device is positioned in the fluid flow path between the isolation valve and the fluid distribution device.
20. A method of providing an indication to a user as to a potential fluid leak associated with an isolation valve in a fire suppression system, the fire suppression system including: a fluid distribution device; a fluid flow path for connecting the fluid distribution device to a fluid source; an isolation valve; and a discharge valve positioned in the fluid flow path between the isolation valve and the fluid distribution device; wherein the method includes: closing the isolation valve; opening the discharge valve to at least partially drain the fluid flow path of fluid; closing the discharge valve; sensing the pressure of a fluid at a location in the fluid flow path; generating a signal indicative of the sensed pressure at the location; and providing an indication to a user of a potential fluid leak associated with the isolation valve.
21. A method according to claim 20, wherein the step of sensing the pressure of a fluid at a location in the fluid flow path includes sensing the pressure of fluid between the isolation valve and the fluid distribution device.
22. A method according to claim 20 or claim 21, further including sensing the pressure of a fluid at a location in the fluid flow path at predetermined time intervals.
23. A fire suppression system substantially as hereinbefore described with reference to and as shown in the accompanying drawings.
24. A method of providing an indication to a user as to the location of a potential fluid leak in a fire suppression system substantially as hereinbefore described with reference to and as shown in the accompanying drawings.
25. A building substantially as hereinbefore described with reference to and as shown in the accompanying drawings
26. Any novel feature or novel combination of features described herein and/or shown in the accompanying drawings.