Most pipeline systems require some form of check valve device to maintain flow in one direction to prevent either contamination of liquids already in the system or damage to the pipework and its ancillary components. Quite a simple function you might think! - bitter experience however tells us a different story.

What are the features that the piping engineer is looking for?

• Tight shut off under minimum back pressure
• Quick response to no-flow or reverse flow conditions.
• Low resistance to forward flow
• Lightweight construction.
• Ease of installation with unskilled operators
• No maintenance.

The NORVAL - Non Return Valve has all these features plus one or two less obvious benefits.

• It is extremely simple.
• It operates in any direction, vertically up or down, or horizontal.
• High material specification.
• Less noise due to slamming shut under reverse flow.
• Can be incorporated in a variety of body configurations or simply built into original equipment as a cone and diaphragm assembly.

Method of Operation

Flow takes place in the direction of the arrows under forward and reverse flow.

A -Valve Open            C -Diaphragm
B -Valve Closed          D -Cone

With flow in the forward direction the diaphragm deflects inwards (A) allowing easy passage of the liquid with little pressure loss. When a no flow, or back pressure, condition occurs the diaphragm returns to its relaxed position (8) sealing off all flow in the reverse direction.

This action is unaffected by the orientation of the valve.

Products and Types

Valve Specification 1 | Valve Specification 2 | Valve Dimensions | Performance