Pressure vessel volume
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May I ask: Does the volume of a pressure vessel include the geometric volume of the nozzles?
In accordance with the definition of containers specified in clause 1.6 of GB/T150.1-2024
Theoretically, it should include the volume of the Takeover.
This post was last edited by tcdlb on 2025-3-26 at 13:34. According to GB/T150-2024, fittings fall within the scope of pressure vessels; therefore, their volume should be calculated, with the volume of small fittings being negligible
Conclusion: The volume of pressure vessels (TSG 21, GB/T 150) includes the geometric volume from the nozzles to the first connection； The small nozzle can be neglected for engineering simplification. I. Regulatory/standard definitions (domestic): TSG 21-2016 \"Regulations on Large Capacity Vessels\". Capacity: geometric volume, calculated based on the dimensions specified in the drawings (without considering manufacturing tolerances), minus the volume of internal permanent components ； Takeover has not been ruled out. GB/T 150.1-2024 3.1.2 Volume: geometric volume, calculated based on the dimensions specified in the drawing and rounded off ； Subtract internal permanent internals ； Takeover has not been ruled out. GB/T 150.1-2024 1.6 Scope of application: The vessel body includes: the first circumferential weld from the nozzle to the connection with external piping / threaded end face / flange sealing surface. II. International terms (EN/ISO) EN term: chamber volume – including the volume from the nozzles up to the first connection. III. How to calculate the engineering value (practical application): For connectors with a diameter of ≥DN50 and a relatively long length, their volume must be taken into account (it affects the classification category as well as the MPa・L product). Small nozzles (DN≤40, especially DN15/20): they account for a very small volume and are often ignored in engineering practices; in design/specifications, only the cylinder, head, and large nozzles are taken into consideration. Manhole/Handhole: It belongs to the category of \"open-ended nozzles\", and its section volume is taken into account. IV. Remember in one sentence: The regulatory definition includes from takeover to the first connection ； Engineering diameter: large pipes are included, small pipes are ignored.