According to EN 736-1, a positioning element (e.g. valve) in a system
of pipes, tanks, machines,…
has the purpose of
switching (on/off) and » on/off duty, isolating duty or
seting (continious/intermittent) » modulating duty, step-control
duty
a fluid or substance. .
Valves are categorized according to the movement of the throttling
body with reference to the flow direction, and the operating principle
of their seal.
The category of valve determines the actuator type and the required
output shaft of the actuater.
plug
valve
|
A linear movement of the disk with or against the flow.
In the OPEN position the flow is over or against the disk. |
ball
valves
|
The
ball in the body rotates 90° about axial shafts.
In the OPEN position the flow runs through the ball. |
|
butterfly valves
|
The disk in the valve
rotates about the stem through an angle of 90°.
In the OPEN position the flow runs around the control body.
|
gate valves
|
The
gate moves in a linear direction across the flow.
In the OPEN position the flow runs through the valve body. |
|
plug valve
|
ball
valve
|
butterfly
valve
|
gate
valve
|
|
