3003 W CASINO RD BLDG 40-87 2025-08-21

TFP1020 Page 5 of 20 Maximum System Air FLOW RATE IN LITRES PER MINUTE(LPM) Water Supply Pressure (1 GPM=3.785 LPM) Pressure Range 500 700 1000 2000 3000 5000 10000 psi psi 9.0 � 0,60 20 10 a 7.0 0,50 60 15-23 = 80 20-28 0,40 z 5.0 100 25-33 Lu 4.0 0 0,30 Z� 145 36-43 O 3'0 Q 0,20 m 165 40-48 � 185 45-53 a 2.0 O Oa Q 205 50-58 0 ^� 0,10 tr m Lo 225 55-63 Z =�O� Q 0,08 LLJ°' 250 1 60-68 a 1.0 V� O= D o TABLE B z G� 0,06 co o 2 D C 0,05 w n SYSTEM AIR PRESSURE a 0.7 N = � REQUIREMENTS � ^� (0 0,04 a a p 0.5 ti z w 0,03 Operation r[ 0.4 0 0 0.3 0,02 Z The TYCO Model DPV-1 Dry Pipe Valve a is a differential type valve that utilizes a a 0.2 substantially lower system(air or nitro- Q gen) pressure than the supply (water) 0,01 pressure, to maintain the set position o shown in Figure 2A. The differential Z 0.1 nature of the DPV-1 is based on the 100 200 300 500 700 1000 2000 3000 area difference between the air seat FLOW RATE IN GALLONS PER MINUTE(GPM) and the water seat in combination with The approximate friction losses,based on the Hazen and Williams formula and expressed in equivalent length of the ratio of the radial difference from Schedule 40 pipe with C=100 and flowing at typical flow rates,are as follows: the Hinge Pin to the center of the Water 2-1/2 in.valve at 250 GPM flow=2.2 ft 4 in.valve at 600 GPM flow=8.9 ft Seat and the Hinge Pin to the center of 3 in.valve at 350 GPM flow=4.9 ft 6 in.valve at 1500 GPM flow=22.0 ft the Air Seat.The difference is such that GRAPH A 1 psi (0,07 bar) of system air pressure MODEL DPV-1 DRY PIPE VALVES can hold approximately 5.5 psi (0,38 1 NOMINAL PRESSURE LOSS VS. FLOW bar)of water supply pressure. Table B establishes the minimum sure of 100 psi (6,9 bar). It is for this After a valve actuation and upon sub- required system air pressure that reason that the plunger of the Auto- sequent closing of a system main includes a safety factor to help prevent matic Drain Valve must be depressed control valve to stop water flow, the false operations that occur due to water during several of the resetting steps, Clapper Assembly will latch open as supply fluctuations. as well as during inspections, making shown in Figure 3D. Latching open of certain that the Automatic Drain Valve the DPV-1 will permit complete drain- The Intermediate Chamber of the is open. ing of the system (including any loose DPV-1 is formed by the area between scale)through the main drain port. the Air Seat and Water Seat as shown in When one or more automatic sprin- Figure 213. The Intermediate Chamber klers operate in response to a fire, During the valve resetting procedure normally remains at atmospheric pres- air pressure within the system piping and after the system is completely sure through the Alarm Port connection is relieved through the open sprin- drained,the external reset knob can be and the valve trim to the normally open klers. When the air pressure is suf- easily depressed to externally unlatch Automatic Drain Valve (Fig. 3, 4, or ficiently reduced, the water pressure the Clapper Assembly, as shown 5). Having the Intermediate Chamber, overcomes the differential holding in Figure 2E. As such, the Clapper Figure 26, open to atmosphere is criti- the Clapper Assembly closed and the Assembly is returned to its normal set cal to the DPV-1 Valve remaining set, Clapper Assembly swings clear of the position to facilitate setting of the dry otherwise the full resulting pressure of water seat, as shown in Figure 2C, pipe sprinkler system,without having to the system air pressure on top of the This action permits water flow into the remove the Handhole Cover. Clapper Assembly cannot be realized. system piping and subsequently to be discharged from any open sprinklers. For example, and assuming a water Also,with the Clapper Assembly open, supply pressure of 100 psi (6,9 bar), if the intermediate chamber is pressur- the system air pressure is 25 psi (1,7 ized and water flows through the alarm bar) and there was 15 psi (1,0 bar) port (Ref. Figure 26) at the rear of the pressure trapped in the Intermediate DPV-1 Valve to actuate system water Chamber,the resulting pressure across flow alarms. The flow from the alarm the top of the Clapper would only be 10 port is also sufficient to close the oth- psi (0,7 bar). This pressure would be erwise normally open Automatic Drain insufficient to hold the Clapper Assem- Valve in the valve trim. bly closed against a water supply pres-