On drum level, why we are using air to close Control valve?
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Answer Posted / carl_ellis
If the valve's actuator is Air-to-Close, what state does it
fail-safe state?
Check out the article, "How to destroy a boiler - Part 1"
at this link:
http://www.nationalboard.org/index.aspx?pageID=164&ID=238
and scroll down a couple pages to the section entitled "Low
Water Conditions".
The description will provide details that help you
understand what the fail-safe state due to the loss of a
control signal on a boiler feedwater control valve should
be.
Carl Ellis
Measure First
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