The maximum operating pressure is indicated on the pressure vessel nameplate – how should this be understood?
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Some pressure vessel nameplates indicate the maximum operating pressure; how should this be interpreted in order to determine whether the setting pressure of the safety valve complies with relevant regulations? Currently, the setting pressure of the safety valve is higher than the maximum operating pressure of the equipment, but not exceeding its design pressure.
It’s not the maximum allowable operating pressure, right? Perhaps the maximum operating pressure here is just the normal operating pressure
I just want to clarify how to understand “maximum working pressure”.
Working pressure and maximum working pressure are concepts belonging to the same category, while the maximum allowable working pressure MAWP and the maximum allowable pressure MAP are also concepts of the same category; do not confuse them.
The maximum operating pressure is the highest value of the operating pressure; it’s fine to write it this way as shown in the original diagram. The set pressure of the safety valve should be higher than the maximum operating pressure of the equipment, but it may not exceed the design pressure of the equipment.
Generally, the medium used in such containers is highly toxic or poisonous, as well as flammable and explosive; they are equipped with safety relief devices, and therefore leakage tests are required. The maximum (high) operating pressure is specified during design, and this value is indicated on the nameplate. The maximum (high) operating pressure can be higher than the design pressure. The setting pressure of the safety relief device is higher than the design pressure but lower than the maximum (high) operating pressure, thereby preventing the safety relief device from activating during the leakage tests.
The “maximum (high) operating pressure” you mentioned here should be “maximum allowable operating pressure”. They mean different things.
There is no such thing as a maximum or minimum working pressure; it refers to the highest pressure that can be reached at the top of the container under normal operating conditions. There is also a maximum allowable operating pressure, which is something different from the operating pressure itself!
During our review, the expert asked us to set the maximum allowable working pressure indicated on the nameplate to be the same as the design pressure.
The nameplate here indicates the “maximum operating pressure”, rather than the “maximum allowable operating pressure”.