CHECK VALVE

LVF Check Valve

A one-directional valve which prevents reversal of flow by means of the check mechanism, the valve being opened by the flow of fluid and closed by the weight of the check mechanism when the flow ceases, or by back pressure.

CHECK VALVE PATTERNS

Horizontal pattern          

In which the body ends are in line with each other, for installation in a horizontal position.

Vertical pattern               

In which the body ends are in line with each other, for installation in a vertical position.

Angle pattern   

In which the body ends are at right angles to each other for installation at a junction between vertical and horizontal positions.

TYPES OF CHECK VALVE

Swing type         

A check valve in which the check mechanism incorporates a disk which swings on a hinge.

Lift type              

A check valve in which the check mechanism incorporates a disk, piston, or ball which lifts along an axis in line with the axis of the body seat. Lift type check valves are described, according to the type of mechanism, as follows:—

a. Disk check     

A check vaive in which the check mechanism is, or incorporates, a disk.

b. Piston heck (or dash pot valve)            

A disk check valve in which is incorporated a dashpot, consisting of a piston and cylinder, which provides a cushioning effect during operation.

c. Ball check       

A check valve in which the check mechanism is a ball.

Screw-down stop and check valve          

A check valve which incorporates a mechanism which can hold the disk in the closed position independently of the flow or, alternatively, can restrict the lift of the disk.

Foot valve          

A check valve fitted to the bottom of a suction pipe. A strainer is often fitted to this valve.

 

 See:  «Clapper».