Answer Posted / ahmed rashed
yes you can as evry body said the control valve with out
positinor can use as on/off controller
and this the apllication to use valve with positinor:
1-split range cntrol action.
2-reverse acting actuator.
3-valve size large than 3"(8cm)
4-actuator power requirment in excess of controller out put.
5-valve design inhrent of flow chractristics change.
6-line pressure above 20bar or delta pressure more than 14
bar
7-quick response actuator.
8-elminated the hystersis.
while the valve without positinor the stem fraction can
cause a control valve to exhibit hystersis
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