Various types of Valves have been developed to cater to
the diversified requirements of fluid control in various applications. These
types of valves match the systems, fluids, and environments to accomplish their
intended function.
Each type of valve has been designed to meet specific
needs. Some valves are capable of throttling flow, other valve types can only
stop flow, others work well in corrosive systems, and others valves handle
high-pressure fluids. Each valve type has certain inherent advantages and
disadvantages. Understanding these differences and how they affect the valve’s
application or operation is necessary for the successful operation of a
facility.
Although all valves have the same basic components and
function to control flow in some fashion, the method of controlling the flow
can vary dramatically.
Each method controlling flow has characteristics that make
it the best choice for a given application of function. One valve may be best
fit for one application but may not be fit for other at the same time.
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| Classification of valves |
Classification of Valves
Fluid control valves are classified in many ways.
Following is the classification of valves.
Multi Turn
and Quarter Turn Valves
Multi turn valves need many turns of actuator to bring closure
member (disc) from fully open position to fully closed position. Examples of
multi turn valves are gate valves, globe valves, needle valves, and diaphragm
and pinch valves.
While quarter turn valves need only quarter ,0 to 900
degree, motion of closure member (disc) to bring it from full open position to
full closed position. Examples of
quarter turn valves are butterfly valves, ball vales and plug valves etc. Quarter
turn vales are quick opening valves.
Self
actuated Valves
Self actuated valves don’t need actuator to operate them. These
valves operate based on some property of fluid line like pressure or flow. Self
actuated valves don’t need operator’s interference to control the fluid.
Examples of self actuated valves are check valves and pressure relief valves or
safety valves.
Linear
Motion and Rotary Motion Valves
In linear motion valves, disc moves in linear or straight
path to open, close or throttle the flow in valve. While in Rotary motion valves,
disc rotates to open, close or throttle the flow. Examples of linear motion
valves are gate valves, needle valves, globe valves, diaphragm valves and pinch
valves. Examples of Rotary motion valves are ball valves, butterfly valves etc.
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| General types of valves |
General
Types of valves
In general following are the types of valves.
- Gate valve
- Globe Valve
- Pinch Valve
- Needle valve
- Diaphragm valve
- Ball valve
- Butterfly Valve
- Check valve
- Pressure relief Valve (safety or relief valve)
