Closed-loop foam-water spray system

I. Product features and scope of application

Closed foam-water spray fire extinguishing system is a type of automatic water-foam combined fire extinguishing system. It is based on the wet automatic water spray system and adds a foam liquid supply device. The entire system is usually in a state of alert. Once the protected object catches fire, the system can quickly spray foam to cover the protection area, prevent the spread of fire, control the fire, and then use fire-fighting water to extinguish the fire and prevent re-ignition.

This system is mainly suitable for indoor areas where flammable liquids or flammable solids are stacked, such as underground parking garages, aircraft maintenance warehouses, chemical dangerous goods warehouses, and production workshops.

II. System composition and system principle

The system mainly consists of water source, fire pump, wet alarm valve, water flow indicator, foam storage tank, proportioning mixer, foam control valve, closed sprinkler head, fire detector, control cabinet, end water test device, supporting control valve and piping, etc.

III. Installation diagram of closed foam-water spray system

IV. Installation and commissioning work instructions

A: Please follow the relevant regulations of the "Construction and Acceptance Specification for Foam Fire Extinguishing Systems" for installation.

B: The foam tank should be horizontally placed at the designed position on the construction drawings, and a 30-50cm reinforced concrete foundation should be made below the tank base, and fixed bolts should be embedded or fixed with expansion screws.

C: The proportioning mixer should be connected in the direction of the water flow indicator: the inlet flange should be connected to the outlet of the wet alarm valve, and the outlet flange should be connected to the corresponding protection area piping network. The inlet check valve should be connected to the foam tank outlet valve.

D: The solenoid valve should be connected to the DC24V control line in the fire control system, and the foam control valve should be opened by this control line in case of fire.

V. Maintenance and upkeep

1. Check the appearance at least once a month. There should be no leaks at each valve and connection, and each valve should be in the designated position.

2. After each use, the storage tank and piping must be flushed with clean water. If necessary, the equipment surface should be repainted and anti-corrosion treated.

3. The foam liquid should be kept away from direct sunlight and stored in a place with small temperature changes to prevent direct contact with air. When stored for a long time, it should be sampled and tested. If it deteriorates, it should be replaced in time.

4. In standby mode, the foam should always be filled in the tank.

VI. Precautions:

1. The mixing ratio of the selected foam liquid should be the same as that of the foam proportioning mixer.

2. For water-soluble (polar) class A, B, and C liquids, anti-solvent foam liquid must be selected.

3. When filling foam liquid, keep the capsule clean and do not mix with oil, water, or foam liquids of different types. Foam liquid types cannot be mixed.

4. The foam proportion mixing device should not be used beyond the working pressure range.