FOAM PROPORTIONED BLADDER TANK

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Description

The Bladder Tank is one component in a balanced pressure foam proportioning fire protection system. It requires no external power other than water pressure to ensure correct operation. The Bladder Tank are designed and costructed in accordance with the latest revisions to ASME Code, section VIII or to  European PED codes, for unfired pressure vessels with a working pressure of 12 bar and are tested to one and one half times this pressure.
A flexible nylon reinforced hypalon like rubber internal bladder holds the foam concentrate and keeps it from coming into contact whit water or the inside of the tank shell. The center discharge piping, located within the bladder, insures that the foam concentrate flows to the bottom discharge. (SES-ASA Engineering Bladder Tank is available also with the foam concentrate in the tank shell. The center piping supply water into the bladder and insures the foam to flow upside the tank shell).
With  foam into the bladder during operation, water  supplied from the system fills the area outside the bladder, gradually displacing the foam concentrate inside the bladder causing the bladder to collapse until the supply is exhausted. The Bladder Tank discharges foam concentrate for the internal or remotely mounted ratio controller at approximalely the same pressure as the water supply. Since the Bladder Tank system is  pressurised during the operation, the bladder can be refilled with concentrate only when system is not in use. In case the foam is in tank shell, the water supplied from the system fills the bladder which expands pushing the foam from the shell until supply is exhausted.
Tank shell and bladder include all necessary drain and vent valves, concentrate fill piping and fill cup, in accordance with NFPA requirements for valve supervision.
When installing a vertical Bladder tank, consider the possibility that in the future, the bladder tank and center tube may require removal. Remember that in the requires access from above the tank in order to remove the piping and the bladder. If possibile, it should be installed in an area that is at least twice as high as the tank or a roof hatch should be installed above the tank.
When installing a horizontal style Bladder tank, it also requires horizontal clearance as well as a clear at one end, wich should be at least twice as long as the tank. Access through double doors is acceptable