Discuss whether it is feasible to replace the shut-off valve with a control valve
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This post was last edited by XJTZWKDPJ on 2010-11-1 at 12:28. The facility is using a domestic single-acting solid ball valve, but the process requires it to be changed to a control valve. 1. We would like to replace the actuator of the shut-off valve with the positioner of a control valve; is this feasible? 2. Is it possible to replace the solenoid valve of the shut-off valve with a valve positioner? The operating air pressure for the valve is 4–5 kilograms, and the diameter is DN200. Please do not reply with anything unrelated to this topic
The function of a cut-off valve is to quickly shut off flow in a short period of time, thereby protecting the system. Changing it to a traditional locator will make it move very slowly when in action. It’s possible that it won’t provide any protection at all!
It is still necessary to consider whether the process requirements are met. From the perspective of the instrumentation team, there is no issue with replacing the shut-off valve with a control valve; in fact, when the process conditions permit, shut-off valves equipped with valve positioners can be used to ensure rapid shutdown in emergency situations, while allowing for adjustment of process parameters when regulation is needed. Could it be recommended not to remove the solenoid valve, but instead install a positioner so that both regulation and shutdown can be achieved?
This post was last edited by XJTZWKDPJ on 2010-11-1 at 19:29. The idea mentioned in the third floor comment is good – it can be used for both cutting off and adjusting flow. However, there is no need for immediate cutting off in terms of the manufacturing process; what I know is that solid ball valves do not require adjustment.
The adjustment effect will be very poor; it is recommended not to do this.
It is possible to make changes, but the adjustment effect is not good. If you don’t want to replace the valve, you can replace the valve core with one that has a V-shaped opening; this way, the flow characteristics of the valve can be changed to equal percentage or quick-opening type.
We have used many valves with switches and regulators; in your case, add a valve positioner and modify the air circuit. That’s possible, but I’ve never seen solid ball valve cores; they are all V-ball and O-ball valves with angular stroke
The key point is that ball valves are of the quick-opening type and do not have any regulating capabilities. Making such a change doesn’t really make much sense.
Moderators, please don’t let the posts get buried; let’s keep communicating
We have already achieved success in experiments there, and it has been put into use. Adjustment is no problem; it’s just that the stroke is a bit short.
It is certainly possible to make changes, but the results will not be good; the characteristics of the valve cannot be the same as those of a control valve.