Answer / anand

There are 3
valve
characterstics
equal percentage
Linear
Quick opening

Answer / nanjilll

Characteristics of control valve:

1. Quick opening => Large change in flow for a small change in Valve travel.(eq. 50% opening gives 90% flow).Usually used as on/off valve

2. Linear => change in flow rate is directly proportional to the change in valve travel(40% flow for 40% valve travel)

3. Equal percentage => not linear but logirthemic variation.

Answer / m.hassan abbas

Relationship
between flow through the valve and
percent rated travel as the latter is
varied from 0 to 100 percent. This
term should always be designated as
either inherent flow characteristic or
installed flow characteristic.

Answer / ecxlsync

the characteristic of control valve is to open/close partially (by percentage)or fully in corresponds to the command signal from the controller. the open/close action of the CV is linearly proportional to the command signal via a valve positioner (I/P).

Answer / sushruta mohanty

THE CHARACTERSTICS OF CV IS
1. LINEAR
2. EQUAL %
3. QUICK OPENING
4. PAREBALLIC
5. HYPERABALLIC.

Answer / faiyaz ahmad

Quick opening
Equal Percentage
linear
Hyperbolic
Square root

Answer / kuldeep

We design CV depend upon following ch's:
1. Flow rate
2. Consistence
3. Temp

I HAVE GOT TYPICAL PROBLEM WITH THE TEMP.INDICATION. THE PROBLEM IS THE K-TYPE T/COUPLE OUT PUT IS CONNECTED TO A INDICATOR.THE INDICATION FLUCTUATES SOME TIMES AND SOME TIME IT IS STABLE. WHEN I CHECKED OUT PUT OF T/COUPLE THE MV WILL NOT VARY. WHERE AS INDICATION FLUCTUATES. WHEN I GIVE MV SOURCE TO T/COUPLE EXTENSIONCABLE FROM THE FIELD IT INDICATION IS STABLE. WHEN GIVE MV SORCE TO INDICATOR ITS INDICATION IS STABLE. PLEASE CLARIFY.

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