Foam spray

Foam - water spray system

1Instructions
Closed foam water sprinkler fire extinguishing system is a type of automatic sprinkler foam combined fire extinguishing system. On the basis of the original wet automatic sprinkler system, it adds a foam liquid supply device, which can spray both water and foam. When foam meets the flame, it can produce a combination of sealing effect, cooling effect, steam effect and other fire extinguishing effects, so it has good fire extinguishing efficiency. The fire extinguishing system adopts aqueous film-forming foam extinguishing agent or film-forming fluoroprotein foam extinguishing agent. This foam extinguishing agent forms an aqueous film on the surface of flammable liquid as a barrier to isolate air and oxygen, and has the ability to inhibit the surface evaporation of flammable liquid, thus improving the fire extinguishing effect and preventing fire re ignition. The water spray system has a better fire extinguishing effect because of the addition of foam extinguishing agent, which saves fire extinguishing water and is more meaningful in water shortage areas. The closed foam water spray fire extinguishing system is a more advanced automatic water spray fire extinguishing system, which can completely replace the ordinary automatic water spray fire extinguishing system, and its fire extinguishing effect is better.
Closed foam water spray fire extinguishing system is widely used in underground garages and places with more flammable liquids. For example, docks and docks for loading and unloading petroleum products, storage warehouses for flammable liquids, horizontal oil tanks, oil pump rooms, fuel boiler rooms, aircraft maintenance garages, etc. This fire extinguishing system has the ability to quickly extinguish oil fires, with high extinguishing efficiency, water conservation, low equipment investment costs, and low maintenance and upkeep costs. Therefore, it has great development prospects.

IIworking principle

Working principle of closed foam water spray system (see figure): when the wet alarm valve is in the supply state, the whole system is full of water under working pressure. Due to the function of constant ratio pressure reducing valve, the pressure of foam liquid provided by foam liquid storage tank is lower than the water pressure in the main pipe network. At this time, foam liquid can fill the entire foam liquid transmission pipeline to the inlet of foam proportioner. Due to the isolation of one-way valve at the mixer inlet, the water in the pipe network cannot flow back into the foam liquid pipeline. When the closed nozzle in the protected area bursts due to a fire, the pressure on the wet alarm valve system side decreases, the alarm valve opens, and the water flowing out from the alarm port drives the hydraulic alarm bell to sound after passing through the delay device. At the same time, the water flow opens the dual-use control valve (foam liquid control valve) through the control pipeline, shortens the pressure reducing valve, and the pressure in the foam liquid tank rises, making the pressure of foam liquid rise to the same pressure as that in the main pipe. The foam proportional mixing device flows to the nozzle according to a certain mixing ratio, and extinguishes the fire through the blasted nozzle.

IIIProduct structure and main technical parameters
Specification and model: ZPSP32/10
Nominal diameter: DN100
Flow rate: 4~32L/s
Working pressure range: 0.6-1.2MPa
Mixing ratio: 3% or 6%
Pressure loss: ≤ 0.2MPa
Foam tank volume: 0.6, 0.8, 1.0, 3.0
Note: The volume of foam tank and the nominal diameter of inlet and outlet can be matched according to customer requirements


4maintenance

1. After the system is installed, the hydraulic test shall be carried out, and the test pressure shall be 1.1~1.5 times of the rated pressure of various components. If the foam spray test is carried out, the pipelines of various components shall be cleaned and flushed immediately after the test;
2. The connections of various components in the system should be correct and error free, especially the proportional mixer should be installed in the direction indicated by the product. Generally, it is required that the length of the upstream straight pipe section of the proportional mixer be ≥ 10 times the inner diameter of the main pipe of the proportional mixer, and the length of the downstream straight pipe section be ≥ 1 meter;
3. Each part of the system should be installed and used strictly in accordance with the instructions (such as flow rate, inlet working pressure, combination sequence, etc.);
4. The foam stock solution should be replaced regularly, and the replacement time should be determined according to the regulations of the foam manufacturer and the factory date. Generally, the validity of foam stock solution is 2-3 years, the storage temperature is 0~40 ℃, and the temperature of the mixed solution is 5~35 ℃;
5. When replacing and filling foam stock solution, be sure to pay attention to the type of foam stock solution applicable to the system and the protection object;
6. When filling foam stock solution, a pump is usually used to fill it from the lower connection port of the capsule. When filling, the exhaust valve and the ball valve of the water inlet pipe connecting the capsule should be opened until it is full (the capsule exhaust valve leaves the foam stock solution). In general, a self-priming pump is used to fill foam stock solution. When the pump fills the capsule with foam stock solution, it should be continuous. After filling, the suction pump should be immediately cleaned with clean water;
7. The pressure and flow of the water source, the water reserves and the reserves of foam stock solution must meet the conditions of the corresponding equipment and the protection objects;
8. At least check the sequential system and main components monthly, such as water pump, proportioner, foam stock solution, valves and valve opening position, to ensure the normal use of the system, and make records for each inspection;
9. All normally open and normally closed valves, as well as components of the proportioner that operate normally, should be labeled with signs to prevent operational errors;
10. Test the system once a year and keep records;
11. System maintenance and replacement of components should be carried out by professional personnel to ensure the normal operation of the system, and records should be kept;
12. Properly store the instruction manual.