Actuator repacement
Actuator repacement
(OP)
Dear Sir and specialists
HI
I ask question about changing the actuator of ON/OFF valves. We have many on/off valve in our gas treatment plant and some actuators were damaged and need to use spare parts for some of them and some item we will replace actuator totally. Also we have drawing of valve and some information (e.g force to open and force to close). First my question is: could we replace these actuators with new and another brand? Is there any restriction for replacement?
And second question is: supply spare part for some item is difficult, could we use some spare part from another brands?
Thanks for your helps
HI
I ask question about changing the actuator of ON/OFF valves. We have many on/off valve in our gas treatment plant and some actuators were damaged and need to use spare parts for some of them and some item we will replace actuator totally. Also we have drawing of valve and some information (e.g force to open and force to close). First my question is: could we replace these actuators with new and another brand? Is there any restriction for replacement?
And second question is: supply spare part for some item is difficult, could we use some spare part from another brands?
Thanks for your helps





RE: Actuator repacement
first of all, I believe You should make distinction between rising stem and quarter turn valves, and between position seated and force/torque seated ones (if applicable) and make sure to understand the relevant differences in actuation requirements (for example: force/torque seated valves usually need a little over-travel beyond 0° closed position, while position seated don't; ball valves require a certain amount of torque along the whole 0° to 90° rotation, while triple offset valves have negligible running torques if compared with ones to open or to close, that show up near the 0° closure position only; and so on...).
Then You should check to have all the force/torque figures, for both the valve requirement (from the Valve Manufacturers) and the actuator output (from the Actuator Manufacturer, whoever he is), in order to make them match correctly.
Once You have selected an actuator that gives each valve the proper forces or torques, You can proceed procuring and assembling...
I would advise against mixing parts from different Manufacturers, at least beacause that would broke any guarantees and make the machine performances unpredictable (not to mention other possible drawbacks...).
Hope this helps,
'NGL
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RE: Actuator repacement
RE: Actuator repacement
On the other hand: if you do this, check if opening and closing failure alarms in the system is time based. You do not want to create an alarm by closing too slow.
Most often it is most practical to take a valve out of the system to check operation when mounting a new actuator,if possible.
Good luck!
For some cheaper valves the actuator will cost considerably more than the valve. if this is the case you will be better off changing both valve and actuator.
If the motorized actuator has had a short lifetime, (normal lifetime for good motorized actuators should be (say) 10 to 20 years or more), you should also check quality, operation mode, suitability and advicement from producer on expected lifetime depending on number of operations.
RE: Actuator repacement