what is the meaning of reverse action and forward action of
control valve...
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Answer Posted / www.islamqa.com
For linear motion valves
Direct acting valve:
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valve opens when stem is drawn out of the body
Reverse acting valve:
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valve closes when stem in pushed into the body
reference:
Lessons in industrial instrumentation - version 4 - page:713
Regards,
Ahmed Sabry
Control and Instrumentation Engineer
GPC - General Petroleum Company
CELL.: 00 2 0121367310
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