Manual and Hydraulically Actuated Gate Valves 3

[aboi]

Hi guys,
Can someone please help me out with the differences between;
1.a manual gate valve and hydraulically actuated gatevalve
2.needle valves and gate valves.
i will be very thankful if someone could help me out.

 

[stanier]

Manual gate valve has a handwheel and a hydraulically operated gate valve a hydraulic power cylinder. Some hydraulically operated valves use the water pressure to operate the valve through a series of solenoids. The more common type of hydraulically operated valve is a globe valve. research Cla Val, Singer and Dorot websites.

A needle valve has a slender tapered form so turning the handwheel opens the orifice slowly. A gate valve has a corcular hole with a wedge tha fills the holes. Suggest you research the Crane, Tyco and Hoke websites to see the various types of valves.

 

[hydtools]

See here:

http://www.vma.org/?page=ValveGallery

You can look through the Valve Manufacturers Association website for more information.

Ted

 

[gerhardl]

Advice to Aboi: You, as well as all others, will get more precise answers if you try to give a bit more details when posting questions.

Actual sizes and pressure classes are some of the more important issues.

Example: If you are here talking about larger sizes (more than 4 inch (100mm) for needle valves, a needle valve in the English language, could also describe a complete different type of valve from the common needle valve: a regulating (for pressure and flow control) valve with most common vaned ring or slotted cylinder, up to 40 inches (one meter) or more, constructed to avoid cavitation, and with a wide control span.

(In other languages, for instance German, this type will have a more precise name: 'ringkolbenschieber' translating to 'ring-piston axial (type valve)'.)