Characteristics and Application of Foam Fire Extinguishing System

The foam fire extinguishing system is a fire extinguishing system consisting of a water source, a water pump, a foam supply source, an air bubble proportioner, a pipeline, and a bubble generator. There are many kinds of foam fire extinguishing systems: they can be divided into fixed, semi-fixed and mobile type according to the installation and use modes; they can be divided into liquid spray, liquid spray and foam spray according to the foam spray method; Foam multiples can be divided into low, medium and high three.

General corporate fire fighting flammable liquid fire should adopt low multiple foam fire extinguishing system. The so-called low magnification foam refers to an air foam with a foam expansion ratio of less than 20 times.

Foam fire extinguishing system features

1 . advantage

Low multiple foam fire extinguishing systems have the following advantages:

( 1 ) The system foam has a small foaming multiple and a high foam density. Therefore, the foam does not substantially increase with the heat flow generated by combustion, and is suitable for fighting flammable liquid fires;

( 2 ) The foam is sprayed far, and the effective height of the spray is also large. It is suitable for mobile foam fire extinguishing systems.

2 . Restrictive

Low magnification foam systems are not suitable for the following applications:

( 1 ) It is usually not suitable for fighting a flowing flammable liquid fire;

( 2 ) should not be used to fight gas fires, liquefied gas fires and cryogenic liquid fires with boiling points below 0 °C;

( 3 ) Failure to save live equipment fires;

( 4 ) It is not advisable to use the fire extinguishing system together with the water gun and the water spray system.

Foam Fire Extinguishing System Types and Applicable Places

Low-multiple foam fire extinguishing systems mainly include two types: liquid jet and sub-liquid jet; according to equipment installation, they are divided into three types: fixed, semi-fixed and mobile.

For petrochemical enterprises, semi-permanent foam fire extinguishing systems should be adopted in the flammable liquid tank areas and local places where the fire risk is within the process equipment in the plant area; the flammable liquid independent tank area far away from the plant area has a complex local or single tank capacity. When using a fire truck to fight difficulties, it is advisable to use a fixed foam fire extinguishing system; to prevent flammable liquid leakage fires, oil tank fires, vertical storage tanks with a volume of no more than 200m < sup > 3 < sup >, and tank heights of less than 7m or For horizontal tank fires, mobile foam fire extinguishing systems should be used.

The choice of foam liquid

For non-water-soluble A, B, C liquids, when using liquid spray foam to extinguish, protein foam, fluorinated protein foam or aqueous film-forming foam fluid should be used; when using liquid spray foam to extinguish, fluorine must be used. Protein foam liquid or aqueous film-forming foam liquid. For water-soluble liquid fires of Classes A, B, and C, fire-resistant foam liquid must be used.