
forede Foam Bladder Tanks
In oil depots, chemical industrial parks, docks, airports, parking lots, and various flammable liquid locations, fire risks are high and spread rapidly, making it difficult to control fires quickly with ordinary water. forede's pressure-type foam proportioning device (foam tank) is specifically designed for oil and flammable liquid fires. By precisely mixing foam liquid and water in a specific ratio, it quickly forms a foam covering layer, isolating oxygen and rapidly controlling the fire. It is a core safety equipment in modern fire protection systems.
Foam Bladder Tank structure
A pressurized foam tank mainly consists of these parts:
1.Water Inlet Pipe 2.Foam Outlet Pipe
3.Proportioner 4.Water Drain Valve
5.Foam Discharge/ Filling Valve
6.Level Gauge 7.Main Hole
8. Suction Tube 9.Bladder
10.Tank Shell 11.Evacuation Valve-Bladder
12.Evacuation Valve-Tank 13.Nameplate
14.Hanger 15.Safety Valve
16.Optional Funnel 17.Check Valve

Working Process

Foam Bladder Tank System Working Process
The foam tank utilizes a pressure-based proportioning mixing principle, requiring no electricity or additional power pump; it can operate directly by connecting to the fire hydrant network. When fire water flows through the device, it automatically draws in foam liquid according to a set ratio, forming a uniform and stable foam mixture, which is then delivered to foam cannons, foam guns, or foam generators for highly efficient fire extinguishing.
1.Fire Water Enters the System
When a fire breaks out and the fire pump is started or the fire pipe network valve is opened: High-pressure fire water → enters the proportioner of the foam tank. At the same time, part of the high-pressure water enters the interlayer between the tank body and the bladder, forming external pressure on the bladder
2.Squeeze the Bladder to Expel Foam Concentrate
The bladder is a soft, corrosion-resistant rubber inner tank pre-filled with foam concentrate. As the external water pressure continues to increase → it squeezes the bladder → the bladder contracts → and the foam concentrate is squeezed into the proportioner.

3. Automatic Proportioning by the Proportioner
This is the most critical step: The proportioner has a special Venturi structure (jet structure) inside, which can automatically control the flow ratio of water and foam concentrate.
Common proportions:
- 3% type: 3 parts foam concentrate + 97 parts water
- 6% type: 6 parts foam concentrate + 94 parts water
The entire process is fully automatic, requiring no electricity or manual adjustment, with stable mixing accuracy.
4.Extinguishing Equipment
The proportioned foam mixture → is delivered to: 1. Fire foam monitor 2.Foam gun 3. Foam Chamber 4.Spray foam pipe network
5. Foam Formation for Fire Extinguishing
The mixed liquid inhales air through the foaming equipment, forming a large amount of foam that covers the burning liquid surface:
- Isolates oxygen to achieve suffocation fire extinguishing
- Cools down the temperature
- Prevents re-ignition
- Excellent effect on oil and chemical liquid fires
Application

oil depot

Chemical enterprises

Port Terminal

Airport aprons

Large logistics warehouse

Tunnel fire protection system










