On-site treatment for broken valve stem of return water butterfly valve in circulating water line
Thread Content
Dear colleagues, the butterfly valve for the return water in the circulation water system of our plant has its valve stem broken due to excessive force applied by the staff when operating it; as a result, it can no longer be opened or closed. The pressure of the return water is 0.15 MPa. The plant is about to start operating, yet the return water valve cannot be opened. The other units are functioning normally. If we stop the plant to replace this valve, those other units will also have to be shut down. I would be very grateful if anyone with relevant experience or who has encountered similar situations could provide some guidance
Consider opening the part of the valve stem where the opening degree is indicated, to see if it can be repaired
If the butterfly valve cannot be repaired and stopping operation to replace it is not possible, then if conditions permit, pressure-driven drilling can be considered; a bypass valve can be welded to the valve to allow it to be opened
It’s best to send a picture to see if it can be fixed. A valve stem that can be broken by manual force? ? ? I still need to see what it looks like before speaking :)
Is it the actuator that’s broken or is the valve stem broken? Can the valve stem be welded on or opened with pipe wrenches?
Is it inside or outside the valve stem? If it’s an actuator, it’s simple to handle; welding is sufficient, and anyway it generally doesn’t need to be closed once it’s opened. If it’s inside, then it can only be replaced; the recirculation water system can be replaced in just 3 or 4 hours, right?
OP, please post a picture instead. If it’s only a break on the outside of the valve stem, welding or using pipe wrenches is sufficient ； If it’s internally damaged, stop and replace it.
If shutdown is not possible, drilling must be carried out under pressure while the system is in operation; valves need to be added before and after the butterfly valve, and then those valves opened.