How to define the size of control valve?
Answers were Sorted based on User's Feedback
Answer / www.islamqa.com
#"Cv" for valve is known as: valve sizing coefficient or
valve flow coefficient
#It refers to " how many gallons per minute can pass
through a fully open valve under diffrential pressure of 1
PSI "
#Cv is a unitless value and by getting it's value we can
get the valve size in inch from tables.
#Cv is got from calculations using s/w provided by
manufacturer as we have many parameters affect its value,
and Cv value is critical as it affects valve size which
leads us - if wrong - to oversized valve or undersized
valve, which harm the process.
#Cv - as mentioned - is got from calculations using s/w,
but it has a basic formula for gas service and liquid
service.
#For liquid service:
Q = Cv (DP/ROH)^.5, ROH IS SPECIFIC GRAVITY
#For gas service:
Q = 963 Cv (DP(P1+P2)/ROH*T)^.5, T is gas temperature in
Rankin
Regards,
Ahmed Sabry
Control and Instrumentation Engineer
GPC - General Petroleum Company
ahmedsabry.online@gmail.com
CELL.: 00 2 0121367310
Is This Answer Correct ? | 3 Yes | 1 No |
Answer / bhavesh
wecan seeing value of (cv)means cooficient of valve and as
per desined use pipeline in short we can define control
valve size as per desining requriment.
Is This Answer Correct ? | 1 Yes | 0 No |
Answer / faiyaz
class 150 class 300 class 600 class 900 class 1500 its size of valve according to the size oil and gas and water will be flow
Is This Answer Correct ? | 0 Yes | 0 No |
Answer / venkatesh j
we can seeing valve size and valve tubing and valve colour
Is This Answer Correct ? | 0 Yes | 8 No |
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