A new inlet stabiliser from Blacoh Sentry has ended a continual problem of diaphragm failure on AODD pumps at a US paints manufacturer. The AODD pumps are used in a tank storage area to transfer Texonal to the production facilities within the plant. The AODD pump sits at the bottom of a 6m high Texanol s diaphragm failure torage tank. The inlet ball valves of the pump open and close several times per second. Each time the ball valve is closed, or “seated”, the fluid velocity is abruptly stopped. This creates high pressure spikes, or “water hammer”. The force of the spike severely weakens the integrity of the PTFE diaphragms by distorting its shape with unbalanced pressure loads and concentrating stress onto one area of the diaphragm, causing cold flow. Every time a diaphragm failed, production halted, and solvent was spilled into the containment dyke and lost. A Blacoh Sentry inlet stabiliser was installed on the inlet side of the pump. The inlet stabiliser cushions and absorbs the water hammer spikes created when the pump’s inlet ball valves close. When the pressure spikes are cushioned, the effect of high acceleration head is diminished and the stress is removed, resulting in increased diaphragm life.
