Is the electric control valve still suitable when the process conditions change?
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The process conditions have been changed from an inlet and outlet pressure of 0.1 MPA each to an inlet pressure of 0.5 MPA and an outlet pressure of 0.1 MPA. I would like to know whether the original electric control valve is suitable for these new pressure conditions, and whether it can meet the requirements over the long term If it is sent back to the factory, can the parts be replaced to make it work?
If it’s just a change in pressure, then you should check whether the pressure regulation characteristics of your original control valve fall within your current pressure range. But what I’m referring to is merely a change in pressure within the manufacturing process; if the process conditions change and it’s not just the pressure that changes, then: 1. Does the original valve’s adjustment characteristics still meet the requirements of your current process? ； 2. Does the medium flowing through the valve meet the existing process requirements? ； 3. Are there any special requirements? Does the on/off behavior throughout the entire process meet the existing process conditions in case of unexpected situations? 4. . . . Add it downstairs
At the time of purchase, the inlet and outlet pressures for the electric valve, as well as the type of medium, were determined; the confirmation document sent over also contained the data provided by our side, with the seller not offering any wider range. The process medium remains unchanged
Changing the inlet pressure from 0.1 MPa to 0.5 MPa should not be applicable. The selection of the pressure rating should be based on the actual process pressure; generally, 2 to 3 times that pressure is used as a reference. In this case, however, the pressure rating has been changed by a factor of about 5. While it might just work in such conditions, its service life will not be very long. As for providing it to the manufacturer, they will definitely ask you to replace the valve with one of a higher pressure rating; they won’t replace the component for you. Of course, this is just a personal opinion.
It should still be within the same pressure range; 5 kilograms of pressure is not high, and the differential pressure is not significant either, so there are no issues with using it
This valve was originally supposed to be either a control valve or a regular process valve. A control valve always has a pressure drop. Moreover, electric actuators are generally not as fast in operation as pneumatic actuators. It’s best to first figure out the purpose of the valve itself; only if it is indeed a control valve should you proceed with calculations and make selection considerations.
The inlet pressure has changed; has the flow rate changed? The pressure drop across the control valve has increased, and the flow capacity of the valve has also changed; as a result, the valve stem and seat need to be recalculated. It is also necessary to determine whether the thrust provided by the electric actuator is sufficient. I think the valve stem and seat need to be remade, while there shouldn’t be any issues with the thrust of the actuator.
Be more specific – let’s see if your valve meets the requirements ?
The inlet pressure of the valve changes, but the flow rate remains constant. I asked the manufacturer, and it’s fine as long as it’s no more than 0.6 MPa