Bladder tanks are usually supplied in one of two configurations and are used to reduce pressure surges in pipelines.
The air charge is contained within the bladder inside the tank. The air charge does not come into contact with the liquid in the tank and so cannot be absorbed. Air charge losses due to absorption are therefore not possibel as they have been eliminated. The pumped liquid from the main flows into and out of the main tank, it will come into contact with the tank walls and so compatible materials must be selected.
The bladder is often made from a highly elastic rubber, such as butyl rubber, and may be sized to expand to fit the entire vessel. The bladder will typically be pre-charged at installation with a pre-determined pressure to give the correct operating level in the tank when the unit is connected to the main and at the operating pressure. There must be an anti extrusion plate fixed at the outlet from the vessel to prevent the bladder from being drawn into the main at low pressures. The anti-extrusion plate and inlet size must be selected so that they do not impose a restriction on the flow into and out of the vessel, otherwise the unit will not function correctly as a surge tank.
Each bladder vessel comes with these standard features:
Safety relief valve
Pressure gauge
Air fill valve
Anti-extrusion plate
Drain connection
Internal bladder (membrane)
Any of our standard bladder vessel may be fitted with the following optional features:
Leak detection system
Level gauge
Level transmitter
Pressure transmitter
Drain valve.
Flo-Dyne bladder vessels are pressure vessels and as standard may be manufactured in ordinary carbon steel, low temperature carbon steel or 304/316 stainless steel to the requirements of the pressure vessel code of your choice.
Typically this will be ASME VIII or PD5500, however we can also manufacture to IBR or your local requirement. We will CE mark the equipment if it is to be used within the European Union, if the equipment is to be used elsewhere we will apply a CE mark where requested if possible.
