Answer / magi

Exact positioning of the valve stem
To minimise hysterisis
To linerise a nonlinear system
To use in place where actuator cant produce sufficien force
to move the valve stem

Answer / satish m. patel, bilimora

The valve positioner is used for following reasons.
1. quick action control valve.
2. valve hysteresis.
3. valve used on viscous liquids.
4. split range.
5. line pressure changes on valve.
6. valve bench set not standard.
7. reversing valve operation.

Answer / sathis.b

we control the valve thru the positioner for the require
percentage we need.

for ex: if u want to open the valve 25%, the command give
from control room it will open or close thru' the
positioner also the forward or reverese of the valve
direction.

Answer / vinesh prajapati ,guj. +919974

1) Reduces HYSTERESIS due to function at gland portion
2) Improves Linearity
3) Works as a volume booster and Thus improve the speed of
Actuator opretion
4) Works as a span amplifier when spring range of actuator
is not 0.2 to 1.0 Kg/Cm2
5) Required whenever spli range control is required

Answer / vigneshkumar

Positioner:
A Positioner is like a proportinal Controller.The Set point is the control signal from the primary controller and the controlled variable is the Valve position.

Uses:

1.When the signal Pressure is not enough to operate the control Valve.
2.To make Split range between the valves.
3. It can be used to reverse the action of the actuator from air to open and to air to close & Vice Versa
4.To minimize the effect of Hystersis Effect.
5.To Minimize the Response time for the valve.
6.If the Actuator is spring less Positioner will be used.
7.If the Valve has high friction .

Answer / ddd

CONTINUOS FEED BACK /HYSTERSIS/BOOST UP AIR FOR OUTPUT

difference between vaccum and draft

0 Answers  

what is plc? Basic function of plc? application of plc in industry? What is lader diagram ? What is the main advantage to use plc in industry?

15 Answers   Schlumberger,

give some question relative instrument fitter?

0 Answers   Armco,

how far the two wire transmission (loop power) maximum distance suitable?

2 Answers   PCIL,

What should be hight of CONTROL panel for access & OPERATION What is BIS & INDIAN STD for SAME?

3 Answers  

HOw To Use 24V DC in Instrument?

2 Answers  

what is the meaning if the control valve CV is 27,in terms of selecting procedure?

2 Answers  

How it the difference between force balance system and dispalacement balance system?

0 Answers  

detail of mass flow meter pricipal

0 Answers  

wHAT IS BURST MODE IN TRANSMITTER?

1 Answers   Bhel,

what is start up vent valve ? why it is used in boiler?

8 Answers   ACC, Bhushan Power Steel,

Explain the functions of the CPU of a PLC.

1 Answers