PWZ substation foam spray fire extinguishing device

1. Foam spray fire extinguishing device

Foam spray fire extinguishing device is a new type of fire extinguishing device that uses a premix of water-film foam liquid as the fire extinguishing agent, and sprays it onto the fire extinguishing object through a special water mist nozzle under a certain pressure to quickly extinguish the fire. This fire extinguishing device absorbs the advantages of water mist fire extinguishing and foam fire extinguishing, and is a "high-efficiency, safe, economical and environmentally friendly" fire extinguishing device.

1. Composition and working principle

The foam spray fire extinguishing device is mainly composed of a liquid storage tank, foam premix, partition valve, pipe network and water mist nozzle, starting source (starting bottle group, solenoid valve), power source (power bottle group, pressure reducer), fire detector and electrical control panel (see Figure 8-4-18). Its working principle and procedure are shown in Figure 8-4-19. The device is designed, installed and used in conjunction with the fire automatic alarm and linkage control device to form an automatic fire extinguishing system. The system startup methods are divided into three types: automatic control, electrical manual control and mechanical emergency manual control. In general, electrical manual control should be used. When both automatic control and electrical manual control cannot be performed, mechanical emergency manual operation can be used.

2. Scope of application and characteristics

Foam spray fire extinguishing device can be widely used in the following places: oil-immersed power transformers; fuel oil boiler rooms; fuel oil generator rooms; small oil depots; small oil storage tanks; small car garages; small repair shops; ship cabins and engine rooms, etc. The device has the following characteristics:

① It uses highly efficient fire extinguishing agents, which can be used to extinguish Class A and B fires; it is especially suitable for extinguishing hot oil flowing fires;

② The amount of fire extinguishing agent used is small, the fire is extinguished quickly and there is no re-ignition;

③ Using gas pressure storage power source, no need for fire water tank and water supply equipment;

④The device has three starting modes: automatic, manual and mechanical emergency start, and the starting is stable and reliable.

3. Use and Maintenance

In order to ensure the reliability of the foam spray fire extinguishing device, the user should establish system operation procedures and management system, and specially trained personnel should be responsible for regular inspection, maintenance and testing of the system. Inspection records should be kept. Inspection contents include:

① Carry out appearance inspection on all system components including liquid storage tank, partition valve, supporting components (control valve, pressure gauge, safety valve), pipe network, water mist nozzle, nitrogen starting source, nitrogen power source, control panel, etc. All components should be free of mechanical damage, all pipelines should be well connected and not loose, and the lead seals and safety signs of manual operating devices should be intact;

②The pressure indication value of each power gas cylinder should be above 8MPa;

③The pressure indication value of each starting gas cylinder should be above 4MPa;

④The liquid level of the foam premix should be above the design value;

⑤ The quality of the foam premix should be sampled and inspected every year. If it is found to be ineffective, it should be replaced in time.

Main performance parameters

Device working pressure: 0.35～1.0MPa, the specific working pressure is determined by engineering design

Continuous supply time of the device: ≥10min

Fire extinguishing agent supply intensity: ≥4L/min·m2

Foam spray nozzle working pressure: ≥0.35Mpa

Storage pressure of power gas cylinder group ≤15MPa

System working power supply: AC220V 50Hz, DC24V