Membrane expansion tanks (hydraulic accumulators)

Functions of a membrane expansion tank:

• ensuring stable water pressure in heating systems, hot/cold water supply;
• prevention of pump failure from frequent switching;
• Keeping of water reserve in case of its emergency shutdown.

The main feature of closed-type expansion tanks with a replaceable membrane is the absence of contact of the coolant with the steel inner surface of the tank. The liquid is inside a special flexible container-membrane, the assembly and disassembly of which is carried out through a flange fixed on bolts. The pressure in the membrane tank can be monitored using a manometer. It is also used to adjust the pressure switch to the required operating range of the tank.

Membrane expansion tanks are always selected individually - depending on the amount of coolant used. An incorrectly selected tank volume can lead to various negative consequences:

• flow of coolant through the thread;
• formation of cracks in the contour;
• pressure drop in the system below the minimum permissible level;
• membrane rupture.

It is allowed to install two or more membrane tanks in one system, while the pressure in the air chambers of these membrane tanks must be the same.

Fields of application of the membrane tank:

Heating systems. When the boiler is heated, the temperature of the coolant in it rises and the liquid expands. The liquid is practically incompressible, and if the heating system is not equipped with an additional device that allows to remove the additional volume, then its destruction will inevitably occur.

Water supply and pressure boosting systems. Tanks are used to eliminate "water hammer" and reduce the frequency of turning on pumps. The consumer uses some useful volume of water from the tank without including the pump.

Air conditioning and cooling systems. Tanks are used to compensate for the expansion of the system. Can be used in systems filled with ethylene glycol mixtures and other liquids (refrigerants, etc.).

Fire extinguishing systems. Membrane tanks can be used as containers with fire extinguishing liquid in fire extinguishing systems.