Basic information about valves

[sheraz.pervaiz]

I have some basic queries

1. Where we use hydaulic,pneumatic, electical controlled valve (adv and disadvantage)?

2. What is actuator and how it control the valves?

3. Is solenoid an actuator or what??

 

[IanP]

Re: Basic about valves

Actuators

In Block 5, 'Basic Control Theory', an analogy was used to describe simple process control:
The arm muscle and hand (the actuator) turned the valve - (the controlled device).
One form of controlling device, the control valve, has now been covered. The actuator is the next logical area of interest.

The operation of a control valve involves positioning its movable part (the plug, ball or vane) relative to the stationary seat of the valve. The purpose of the valve actuator is to accurately locate the valve plug in a position dictated by the control signal.

The actuator accepts a signal from the control system and, in response, moves the valve to a fully-open or fully-closed position, or a more open or a more closed position (depending on whether 'on / off' or 'continuous' control action is used).

There are several ways of providing this actuation. This Tutorial will concentrate on the two major ones:

Pneumatic.
Electric.

Other significant actuators include the hydraulic and the direct acting types.
These are discussed in Block 7, 'Control Hardware: Self-Acting Actuation'.

More details at:
https://www.spiraxsarco.com/resourc...n/control-valve-actuators-and-positioners.asp

See also:
https://www.engineersedge.com/hydraulic/electric_solenoid_actuator.htm

Regards,
IanP