Patent Application
20090188567
The present invention relates generally to testing fire suppression fluid sprinkler systems, and in particular the testing of flow switches in fire suppression fluid sprinkler systems.
In a typical fire suppression water sprinkler system as installed in many buildings, an array of individual fire sprinklers is supplied with water through a main conduit and various branch conduits. The individual fire sprinklers are generally provided with a member that melts when the ambient temperature reaches a predetermined level indicative of a fire. The melting of the member opens a fire sprinkler to spray water in order to suppress the fire. The individual fire sprinklers are provided with meltable members so that the spray of water will hopefully be limited to the region of the building where the fire is present. In this way, the extent of water damage may be minimized.
Such fire suppression systems also oftentimes have a switch or sensor that detects the flow of water in the conduits to indicate that even only one of the individual water sprinklers has opened. Since the flow of water in the conduits generally means that a fire is present in the building, the switch or sensor typically triggers a fire alarm or sends an appropriate signal directly to a fire department. Therefore, many codes require, and it is generally otherwise desirable, that the switch or sensor which detects the flow of water in the conduits be periodically tested. Accordingly, it has also become conventional in the art to provide a valve which enables the system to be tested by permitting a flow of water corresponding to the flow through only one individual water sprinkler that has been opened.
Various testing valves and arrangements for testing and also for draining fire suppression systems are known in the art such as are shown and described in U.S. Pat. Nos. 6,302,146, 5,103,862, 4,971,109, 4,995,423, 4,852,610, 4,741,361 all of AGF Manufacturing, Inc. These patents are each incorporated herein by reference.
The main water conduit typically has a plurality of branch conduits including a number of sprinkler heads. Typically, a supply valve either for the entire fire suppression system or for a particular floor or for a portion of the system, is provided in the main water conduit. Downstream of the supply valve is the fire suppression fluid flow sensor which is configured to detect a flow through the conduit corresponding at least to the flow through a single sprinkler head. A testing valve may be provided to provide a flow of fire suppression fluid corresponding to the flow through a sprinkler head.
The water flows through the valves and various arrangement for testing fire suppression systems and is then directed to a drain and into the local waste water system. Although an individual test of a fire suppression fluid flow sensor may require 10 to 12 gallons, in a large multi-story building the testing procedure results in the use of a large quantity of water that is ultimately released into the waste water system.
The construction industry has increasingly recognized the environmental, economic and health and community benefits of providing so-called green buildings. The establishment of the leadership in energy and environmental design (LEED) Green Building Rating System™ recognizes that reducing water consumption provides environmental, economic and health and community benefits. These benefits include conserving natural resources, reducing operating costs, enhancing asset value and profits and minimizing the strain on local infrastructure.
In view of the above background information, it is an object of the preferred embodiments of the present invention to provide a circulation system by which a fire suppression system may be tested, and fire suppression fluid used during testing is circulated to be reused.
It is another object of the preferred embodiments of the present invention to provide a circulation valve and tank arrangement whereby fluid used when a fire suppression system is tested is not discarded as waste.
It is another object of the preferred embodiments of the present invention to provide a fluid tank to hold fluid used when a fire suppression system is tested for eventual reintroduction into the fluid supply.
It is another object of the preferred embodiments of the present invention to provide methods whereby fluid used when a fire suppression system is tested is not discarded as waste.
The above objects as well as other objects not specifically mentioned are accomplished by a valve arrangement for testing a fire suppression sprinkler system, in accordance with the present invention, in which a conduit supplies a fire suppression fluid to a plurality of sprinklers. In the arrangement, a circulation valve is provided downstream of a valve arrangement for testing a fire suppression sprinkler system to direct fire suppression fluid used during testing to a fluid holding tank and then to a circulation conduit to be reintroduced to the fluid supply whereby said fire suppression sprinkler system may be tested without waste of fire suppression fluid.
The preferred embodiments of the present invention will be described in greater detail with reference to the accompanying drawings, wherein like members bear like reference numerals and wherein:
With reference to
During testing of the typical fire suppression system, the fire suppression fluid is permitted to flow at least through the portion of a branch conduit 30 that includes a sensor or flow switch 33 utilizing a test and drain valve 35. The sensor 33 detects the flow through the conduits and either sends an alarm or triggers a mechanical alarm that indicates the fluid flow. Fluid that has passed through the branch conduit 30 during the testing is directed to the drain riser 37 via a drain branch conduit 36 by the test and drain valve 35 provided between the branch conduit 30 and the drain branch conduit 36. The test and drain valve 35 may be operated either locally or remotely to provide fluid communication between the branch conduit 30 and the drain conduit 36 during testing of the fire suppression system. In a non-test mode fluid communication between the branch conduit 30 and the drain conduit 36 may be blocked. In a conventional system the fluid used to test the fire suppression system is drained as waste.
According to a preferred embodiment of the invention, the fluid that has passed through the system during testing and then to the drain riser 37 via a branch conduit 36 may be diverted by a circulation valve 39 into a fluid tank 43 where it may be circulated back into the supply riser 28 to be reused as necessary. The fluid tank 43 may have a size of 50 gallons. However, it should be appreciated that the fluid tank 43 may be any suitable size depending on the system requirements. The fluid tank 43 may include a sensor 90 that detects a fluid level and/or pressure inside the fluid tank 43.
Circulation valve 39 is placed to divert fluid either to drain as waste water or to the fluid tank 43. Circulation valve 39 may be operated to divert fluid to the fluid tank when the system is in the test mode. The circulation valve 39 may be operated remotely. In the event that the fluid tank 43 is determined to be full by the sensor 90 because of a malfunction or for some other reason, the circulation valve 39 may be operated to divert fluid to the drain. The circulation valve 39 may include an alarm switch 91 that indicates to a user that the circulation valve 39 is positioned to circulate the fluid.
As shown in
Because the water provided through the water tank is circulated there may be an increased risk of microbiologically induced corrosion or MIC. MIC can lead to shorter system life by corrosion from microbial action that may result in fatigue and failure of particular conduits. In preferred embodiments of the invention, a metering pump system 50 includes a metering pump 51 which introduces measured amounts of chemicals formulated to neutralize MIC is the conduits. The chemicals are held in a chemical storage tank 52.
The fluid tank 43, the high pressure pump 41, the control components 70, the metering pump system 50 and the circulation valve 39 may be provided in a cabinet 80 suitably located, for example, in a mechanical equipment room. The control system 70 may include any suitable control system, for example, an electrical, an electronic or a pneumatic system capable of operating the components of the preferred embodiments of the invention.
A method of operation according to a preferred embodiment of the invention will now be described. One of gate valves 93,94 is closed to block the fluid from the incoming supply 22. The test and drain valve 35 is placed in a test mode which allows fluid communication between the branch conduit 30 and the drain conduit 36. The circulation valve 39 is positioned so that fluid is directed into the fluid tank 43. The fluid directed into the fluid tank 43 is circulated back into the supply riser 28 by the high pressure pump 41 or the system pump, where it is reused. It should be appreciated that the system and its constituent apparatus may be operated remotely.
A priming line 60 may be provided in fluidic connection with the fluid tank 43 for priming the flow of fluid into the fluid tank 43. A bleeder valve arrangement 61 may be provided between the fluid tank 43 and the circulation conduit 42 to adjust the fluid pressure there between. An air eliminator 63 may be provided to bleed off excess air in the system. A pressure control, pressure regulating, or check valve 62 may be provided in the circulation conduit 42 to prevent flow from reversing. An alarm valve or a “shotgun valve” may be provided in the main fire suppression fluid conduit 28.
The principles, preferred embodiments and mode of operation of the present invention have been described in the foregoing specification. However, the invention which is intended to be protected is not to be construed as limited to the particular embodiments disclosed. The embodiments are therefore to be regarded as illustrative rather than as restrictive. Variations and changes may be made without departing from the spirit of the present invention. Accordingly, it is expressly intended that all such equivalents, variations and changes which fall within the spirit and scope of the present invention as defined in the claims be embraced thereby.
