Dual plate check valve

2 plates or doors open to one side when the flow push against them, they are being held in the closed position by a light spring when there is no flow and hardly any pressure drop is required to open them.​

When the flow is being turned for some reason the doors are closed by the flow which stops the backlfow of medium into the upstream pipe.​
The are typically metal seated but also available with a soft seat.​
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Available in wafer, lugged and double flange body style.​
Common are Carbon Steel, Stainless Steel but also higher grade materials can be supplied