Expansion Vessels

Aquaflex Expansion Vessels incorporate a diaphragm/bladder arrangement which provides a flexible barrier between the system fluid and the precharged air in the vessel. As the system water expands, the bladder also expands, pushing against the precharged air cushion. This is how the expansion is accommodated in a closed-loop system. The NR vessels are fitted with a relief valve preset to 3 Bar. The F and R series vessel’s are not fitted with relief valves. Pressure setting must be specified when ordering.

Pressurised expansion Tanks supplied by Masterflow are the bladder style tanks which have several advantages over the more common diaphragm style because:

1. The water is contained within the bladder, whereas the water in a diaphragm style is in contact with the tank material. This could lead to corrosion & failure of the tank since the makeup fluid has minimal or no direct chemical treatment.

2. Bladder tanks have a higher acceptance volume or capacity than an equivalent sized diaphragm style due to the shape of the membrane. This means that bladder style tanks are potentially a smaller size for a similar expansion capacity.

3. The bladder in a Masterflow Exp Tank can be easily replaced through a plate in the bottom of the tank, whereas diaphragm tanks are totally sealed & need to be replaced if it fails.

4. All expansion tanks supplied by Masterflow and larger than 50 litres have a pressure gage for the airside so it is easy to monitor or adjust the pre-set pressure.

We look forward to the opportunity of
assisting you.

Please contact us with your requirements; we are always ready to listen.

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184 Newton Rd 
Wetherill Park NSW, 2164 Australia

+61 2 9748 2022

+61 2 9748 2099

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