Answer / oscar b. ano-os jr.

In general, valves can be categorized only into two types,
STOP VALVES AND CHECK VALVES... Stop valves are used to
control process flow (i.e 25%, 50%, 75% and so on) while
check valves are used to restrict the flow of process in
only one direction.

Types of Stop Valves are Globe Valves, Butterfly Valves,
Ball Valves, Saunders Valve and other types while the most
coomon tyoe of Check Valve is the Relief Valve used to
deppresurize tanks and vessels...

Answer / www.islamqa.com

We can devide valve types by 3 considerations:

# valve types with considering valve function- so we have:
on/off valve
control valve( or called throttling or modulating valve )
safety/relief valve
check valve

# valve types with considering stem motion- so we have:
linear motion which have: globe, gate, bench valve
rotary motion which have: ball, butterfly, disk valve

# valve types with considering actuator type- so we have:
manual valve
MOV (Motorized Operating Valve)
solenoid valve
pneumatic valve: diaphragm, piston valve
hydrolic valve: piston valve

Regards,

Ahmed Sabry
Control and Instrumentation Engineer
GPC - General Petroleum Company
CELL.: 00 2 0121367310

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