Everyone worked together to subdue this key
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DN250 jacketed insulated ball valve, the jacket is not connected to steam or circulating water, as this valve is not opened and closed frequently. The manufacturer will stop doing advertising. Transmission method: manual worm. Working medium: analysis gas, slightly containing ammonia recently; temperature: 40-70. Service time: less than two years. I wonder if anyone has encountered this situation where the key splits open – was it done intentionally by the manufacturer or is there some other reason for it?
There’s a problem with the material; it’s caused by high torque
There’s probably a problem; this key clearly looks to be made of Q235
It should look like this once it’s made; the picture doesn’t seem to show it twisted like that at the back!
1. In the topic of the floor, “Since this valve is not opened and closed frequently.” What does it mean when a manufacturer stops doing advertising? 2. Since the conditions at the site are unclear, the reasons will not be discussed here; only the possibility that it was intentional on the part of the manufacturer will be examined. 3. In situations where the actuator applies a torque far greater than the maximum allowable torque for the valve stem, torque-transmitting components such as pins or keys require some form of protection, and limiting the strength of these pins and keys is a common practice. 4. During operation, if the valve is opened and closed frequently or there is no scaling inside, the switching torque remains within a reasonable range, so the pins and keys are not damaged. However, when internal blockages occur and it is necessary to change the valve’s state urgently, the operator will try their best to open or close the valve. At this point, since the capacity of the actuator exceeds the allowable value for the valve, the risk of the valve stem breaking increases significantly, which prompts the use of protective measures. 5. Therefore, the possibility that the manufacturer did this on purpose exists. We use such valves in high-risk areas; we have encountered situations where protective measures were activated, and we have also explained this concept to users and maintenance personnel. 6. The above description does not necessarily mean that the example given by the original poster also has such measures in place. 7. If the medium conditions inside the valve in question pose a high risk, it is necessary to take that risk into account; consult the manufacturer to determine whether such a function is available, and if so, do not change it lightly.
Since I don’t understand, I’m seeking advice and discussion. Is there any problem with that?
It seems that it’s designed to be like this; there’s also a pointer indicating the valve opening degree. When the key is in the aforementioned state, without checking the valve opening indicator, it’s impossible to know the actual status of whether the valve is open or closed
Once this situation occurs, if the valve opening indicator is not activated, it becomes impossible to know the actual opening degree of the valve. Is this done to avoid risks or to increase them?
I think you’re right from the perspective of safety related to saturated valves. Consider that these valves are installed at the inlet and outlet of equipment; if they open when they should be closed, or close when they should be open, it’s often not just the valve itself that gets damaged. I’m not sure if this way of thinking is correct
It seems like it was made this way; the valve manufacturer couldn’t possibly make it open. Perhaps it’s a defective product – there are no obvious visual defects, but it separated during use. There should be more than one key on the turbine; check to see if the other key is working properly