The World Leader in Air Valves Technology Incorrect check valve selection can aggravate surge and water hammer in pipeline systems, resulting in what is known as check valve slam, causing pressure transients that may exceed the pipeline working pressure by up to five times. Check valves can also be one of the largest contributors to head loss within a pipeline, which in turn increases power consumption. The Vento-O-Mat range of nozzle check valves addresses both of these concerns by providing a non-slam valve with very low pressure loss. The valve utilises a ring-shaped disc as the closing member. Rapid, slam-free closure is achieved through the use of friction-free helical springs and radial guides. Annular ring-type nozzle check valves outperform centre-shaft nozzle designs (mushroom type) in both dynamic performance and head loss characteristics. This is due to the low mass of the moving components (ring-shaped disc) and the superior pressure recovery inherent in the two-port annular flow configuration.

Advantages and Key Features

• Non-slam closure – The valve responds rapidly to changes in velocity, ensuring the disc is at the point of closure before reverse flow occurs
• Low pressure loss – In the open position, the annular disc creates two flow paths, increasing flow capacity through the valve
• Short closure time – The short stroke length significantly reduces closure time
• Friction-free operation – Helical springs and radial guides allow smooth opening and closing with minimal resistance
• Tight shut-off – Achieved through metal-to-metal sealing
• No scheduled maintenance