Status of the device’s safety valves in operation!
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For the safety valves on the equipment and containers in our normal production units, how many should be in use? Why? Our facility’s requirements dictate that only one safety valve should be used, with the other kept closed and not in use. From a safety perspective, what is the purpose of this? I want to convince them to use two! How can it be said more persuasively!
The installation of two safety valves on the equipment is based on two main considerations: 1. If the design takes into account long-term operation, then one valve is activated during the annual inspection of the other one. So it’s one in use and one as a backup ； 2. If the capacity of a single unit is not sufficient to ensure timely pressure relief during design, or if the diameter of such a unit is too large and there is no suitable location for its installation, then two units with smaller diameters can be used to replace the capacity of one unit; in this case, they need to be operated at full capacity. There were similar posts before; you can take a look at them. The most important thing is to understand why your device is equipped with two safety valves
Since a safety valve has been installed, it should be kept in the open position in accordance with the requirements for its installation, and an indicator indicating that it is in the open state should be provided. Ask them why they haven’t put it into use
I searched for a long time regarding whether to use one or two, but there is no standard guideline; the documents from our company’s logistics and safety departments also don’t specify anything. Among my colleagues at work, there are two different opinions: 1. Two units are installed, one in use and one as a backup, to switch over in case there is a problem with the safety valve or during inspections ； 2. Since two safety valves have been installed, both should be put into use; when inspection is required, only one valve should operate at a time. In the event that one of the safety valves malfunctions and fails to function, the other one can take over its role. I think it’s better to use both units; whether or not a safety valve is used, it still needs to be checked over time. Using both provides double protection. You can explain it this way.
The second floor has covered everything quite thoroughly. I suggest you take a look at how your facility’s safety valves are installed, and then use the reasoning from the second floor to convince your management
Generally, one is used as a backup for the other; this arrangement is applied to relatively important equipment. If a safety valve fails or needs to be inspected, there is a backup available, ensuring that the system always has a safety valve in place； Some companies arrange their backup valves in such a way that two safety valves share one inlet pipeline, with a three-way valve used to switch between them.
Safety valves need to be sent for inspection every year. If they are still in use, does that mean production has to stop so they can be taken down and sent for inspection together? How about using one and sending one for testing, alternating them back and forth~~~:P
We had a meeting yesterday to discuss this; the company insists on using separate systems, with the aim of preventing excessive vibration in the pipelines downstream of the valves in case of overpressure in the equipment. It’s ridiculous!
In your case, it’s as if the security information isn’t clear. What does the design specification say? Can one of them meet the emergency discharge requirements? If it can’t be found, it needs to be recalculated. Also, it was said upstairs that it is to prevent excessive vibration in the pipeline downstream of the valve – can it be assumed that the supporting strength of the drainage pipeline is insufficient? This probably won’t work.
It is best to refer to the original design documents; if one of them meets the pressure relief requirements, then it is sufficient to ensure that one of them is in use, which can generally be achieved through locks or seals.