What is your view on the classification of pressure vessels?

What the poster is referring to is probably equipment with a jacket; it can be classified according to the relevant regulations for capacity.

Does the original poster mean the classification principles of electrical codes, or is there an objection to such classification?

Is it a pressure vessel or a vacuum vessel? I’m not sure what the landlord wants to discuss – whether it’s why vacuum vessels are not classified, or why certain externally pressurized vessels (with jackets) are classified ? ? ?

Why are some externally pressurized vessels (with jackets) classified?

The essence of classification is that damage to the equipment itself can cause serious harm; it serves to enable better management. The common type of jacketed vessel is the semi-jacketed vessel, and the damage caused by the failure of such vessels has the same consequences as that of ordinary vessels. Therefore, classification is necessary. There is also another type: the full jacket design, in which the outer shell encloses the entire inner shell. In such devices, the inner shell is usually already under vacuum, so no classification is required for it. If the pressure in the jacket is greater than that in the inner shell, and both pressures are above 0.1 MPa (which is almost impossible), then from the perspective of classification, there is no need to classify the inner tube, as even if the inner tube is damaged, it will not cause any casualties; moreover, doing so would be illegal. Half-pipe jackets are not included in the above description. Whether a semi-tube jacketed vessel is classified depends on the diameter of the semi-tube as well as the temperature and pressure of the medium

The colleague on the 6th floor said, “...........It’s a semi-jacketed container; the damage caused by its failure has no difference from that of ordinary containers.” Regarding this structural feature, there is a significant difference in the stress experienced by the jacket and that experienced by the inner cylinder; whether this view is valid remains to be discussed.

I don’t know, but I hope to see more information on it!

What I’m referring to is damage and hazards, not the characteristics of stress distribution. In terms of stress, the unenclosed part of the inner shell is no different from that of a regular container; once the enclosed part is damaged, the force acts directly on the jacket, just as it does in a regular container. If the part enclosed by the jacket gets crushed, the next step is that cracks or other damages will appear in that crushed area; as a result, the stress conditions change completely due to the altered shape. Also, classification is not based on the type of stress applied, but rather on the extent of the damage

If it is a vacuum vessel, it is not classified; if it is a jacketed vessel, it should be classified separately

The new version of the “Compatibility Regulations” may eliminate this requirement

I don’t think this rule will be abolished. It’s possible that the materials used for the cylindrical section of the container, whose inner tube is vacuum-sealed and surrounded by a jacket, will also have to comply with the relevant regulatory requirements. If those requirements are indeed removed, I think I’ll have to change careers