【 Weak current College 】 sprinkler system components set of problems---Power By 【 China power house network 】

Summary: with the automatic sprinkler system design code (GB50084-2001) [1] (hereinafter referred to as "the regulation of injection) and engineering practice on sprinkler system design and construction of nozzles, alarm valves, fire water tank and pump adapter issues analysis and discussion.
Keywords: automatic sprinkler nozzles;; alarm valve group; fire; fire water tank; pump adapter
1 nozzles
1.1 sprinkler layout principles and requirements
(1) meet the role of water in the area of strength, sprinkling of uniformity and nozzle opening time (head heating conditions and opening hours);
(2) Nozzles spray RADIUS in flexible layout, there is no white space is not overwritten, it does not appear excessive duplication of coverage;
(3) ensure Jet wet wall and a range of wall;
(4) nozzle should not influence each other between;
(5) according to the specifications and the actual processing of the obstacles blocking, and positive and relevant professional coordination, to leave room for other professional adjustment;
(6) considering the fire plume flow on effect of nozzle movement;
(7) in connection with reality, a comprehensive analysis of the relevant specification.
1.2 Nozzles spray RADIUS and
Water spray RADIUS is the main basis of nozzles, which represents an economic value, while working in the nozzle does not appear blank is not overwritten, it does not appear excessive important coverage. It and set the location of the water hazard class strength, nozzle and work pressure. Engineering design of nozzles depending on the architectural plan, in spray RADIUS range, often using square, rectangular or square shape. Water spray RADIUS is different from the head of the RADIUS, which is calculated on the basis of the RADIUS, consider sprinkling strength, water heating uniformity and sprinkler condition and timely open, according to the norms and values. Specific see table 1. Because the layout is protected by sprinkler other factors impact is large, in fact often occur nozzle is not a fixed distance to the layout, in addition, as a civil engineering design, you need to leave room for the second decoration.
1.3 nozzles of special provisions


In addition to table 1 the General requirements, it should also be combined with site functionality, and purpose of special nozzles. In order to prevent the nozzle for hot air does not over or upper nozzle spray cooling but cannot start, the spray regulation law 7.1.7 stipulates that shelf above are within the nozzle, crevice, holes should be set at the top of nozzle collector retaining plate. Collector retaining plate should be square or circular metal plate, it should not be less than the plane area, bending around 0.12m2 edge along, to splash with the nozzle plate. Also, the garage, garage, parking design fire protection standard "[2] in section 7.2.3, garage, garage fire sprinkler system design in addition to the existing national standards should be the automatic sprinkler system design code of regulations, its nozzles should meet the following requirements: 7.2.3.1 should be set in the garage parking above; 7.2.3.2 mechanical garages, double garage and nozzle except in roof or floor press parking above the layout, you should press parking pallet location hierarchy layout and should set the nozzle plate above the collector. 7.2.3.3 error layer type, inclined floor plate in the garage of the lane, ramp should be set above the head. Set collector retaining plates with purpose and effect is hot and retaining water, but in practice, the collector retaining plates are used more than that, on certain occasions been interpreted, in particular in some places is not suspended ceiling in order to address the nozzle splash plate and the distance between the roof is too large, expanding the collector retaining plate using range nozzle over installation collector retaining plate. But this expansion set heat retaining plate application scope of practice, is not normative. Fire sprinkler head action in the early days, the heat is mainly thermal convection. For being a fire point of nozzle set heat retaining plate can play a very good collection, but if a fire point not being on the nozzle, the collector retaining plate area only 0.12m2, only nozzle protection area 0.6-1.33%, increase in heat convection in the collector retaining plate service aggregation, collector retaining plate has no effect. Thus, the collector retaining plate set, should be carefully considered, and should be based on existing specifications, combining the actual conditions of argumentation.
2 alarm valve group settings
2.1 alarm valve group number
Number of alarm valve group shall be based on two principles to determine, first, the spray control "section 6.2.3, an alarm valve group control number of the nozzle should be consistent with the wet system, preaction system should not be more than 800 only; dry system should not be more than 500 only. Second, the spray regulation law 6.2.4 stipulates that each alarm valve set of water supply of the highest and lowest elevation difference nozzles, which should not be greater than 50m instead.
2.2 alarm valve group settings where and how
6.2.6 the spray regulation law stipulates "alarm valve group yishe in security and ease of operation, alarm valve from ground level should 1.2m. Installation of alarm valve parts should be provided with drainage. "In its section 6.2.8, hydraulic alarm again request should set someone on duty stations nearby, and connectivity with the alarm company, its diameter is greater than the total length is not appropriate to 20mm, 20m. Alarm valve settings should meet the requirements of the role of alarm valve and the control area and the size of the system, the location is safe, easy to operate, easy to manage, near someone on duty, fully reflect its reliability, reminders of evacuation, features such as automatic restart pump.
2.3 water distribution piping material requirements
Alarm valve of water distribution pipe must be hot-dip galvanized steel pipe inside and outside the wall. Alarm valve can be adopted before the pipeline anti-corrosion of steel pipe inner wall does not, however, it must be in the end of the pipeline, which is located between the population before the alert filters, to prevent debris into one alarm valve. The connection to the system piping, alarm valve on the pipeline must use Groove connection i.e. hoop or threaded and flanged connections.
3 fire pumps, fire water tank and pump adapter
3.1 fire pump
Fire pump in the design and construction of the most neglected areas ofTwo, one is not using irrigation-water absorption and do not take other remedial measures. Buildings》 section 8.8.2, "regulations of section 7.5.4," spray regulation article 10.2.3 article have made provisions: the fire pump (including regulators pumps) should be used since irrigation-water absorption. In this way can we guarantee that in the event of a fire, the fire pump starts in a timely manner. The second is the fire pump suction pipe, water supply pipe quantity. Buildings》 section 8.8.2, "regulations of section 7.5.4," spray regulation law section 10.2.4: fire pumps should be set for a period of not less than two suction pipe and the water supply pipe. The fire pump's suction pipe outlet should be located control valves, control valves, check valves should be located, pressure gauges and diameter of not less than the test water valve 65mm.
3.2 fire water tank
Set up automatic sprinkler system is aimed at fighting the fire in the early days. In the nozzle movement time period, the fire will be a few kW per second to 10 kW at the rate of growth, this time open nozzle if not by the strength of continuous water injection, system performance will be significantly reduced, or even make the fire into the development phase, resulting in fire extinguishing the fire of harder that is beyond the capacity of fire-extinguishing system. To ensure open and continuous spray nozzles, and ensure that disadvantaged parts of the timely and effective extinguishing the fire, the spray control section 10.3.1, 10.3.2 stipulates: "the use of temporary high pressure water supply system of automatic sprinkler system, should be set to high fire water tank. Fire cistern, should satisfy the system is the most disadvantageous point minimum working pressure sprayer and spray intensity. "And" building height not exceeding 24m, and press lightly dangerous level or risk level site settings in the wet system, dry system or preaction system, such as high water do have difficulty, you should use 5L/s flow-pressure water sharing equipment supply water. "early 10min The doctrine of the provisions of article 7.4.7 also when using temporary high pressure water supply system, should be set to high fire water tank.
3.3 pump adapter
In the spray extinguishing systems, alarm valve group has integrated non-return valve, pump, located in the valve after (along the water flows) water does not flow backwards, because water fire engines arrived at the scene by pump combination for indoor spraying pipeline transporting water, fire is known, do not need to start again and hydraulic pressure relay alarm alarm or having to start again the fire pump, pump adapter can directly access after the wet alarm valve. But for a system of two or more alarm valve group, is located in the valve after other valve will not be able to the public this pump adapter, so each alarm valve after at least one pump combination. Taking into account the spray regulation law section 10.1.4, "when the automatic sprinkler system is equipped with two and more alarm valve group alarm valve group ago yishe ring water supply piping, for 2 and more alarm valve group system or supposes in valve for good, you can cross to standby. Another pump adapter location should consider the convenience of connecting fire engine water pumps, water should not be too far away.