Which devices require the special seal for pressure vessel design?

According to the Fixed Capacity Regulations, those that do not fall into a certain category are not required to follow these rules

1. General design plan； 2. Strength calculation sheet ； 3. Design change order. (Design changes, material substitutions, etc.) Any document that requires the opinion of the design agency must bear the special design seal (oval in shape, with the corresponding qualification certificate number on it); copies and other formats are considered invalid. Tower systems with a pressure of less than 0.1 MPa are not considered special equipment, and the same procedure is followed by the design institutes. The design firm enforces strict control over its design-specific seals, and generally will not use them anywhere other than on the overall design drawings. In cases where strength calculations and design changes are required, the original design agency must affix its official design seal and obtain signatures at three levels; otherwise, such documents shall be deemed invalid.

As long as it is classified as a pressure vessel, it must be stamped with the special seal for pressure vessel design or the special seal for special equipment design

The issue of stamping the strength calculation document is debatable; during our re-evaluation, experts requested that we make corrections, stating that the strength calculation document must be stamped. Upon visiting the design institute, we found that there are specific regulations in the design standards regarding the stamping of such documents. The final review experts agreed with the design institute’s position, stating that the strength calculation document does not require a design seal. I’ve asked many people about this question! ! It shouldn’t need to be sealed; design changes also don’t require sealing!

According to the regulations on fixed capacity, is it only necessary to affix a special seal on the overall design diagram? Seals can also be seen on the calculation sheets, but this is not mandatory; on change orders, it is common to find the seal of the design department.

Pressure vessels subject to the Fixed Volume Code require a special seal designed for their lids.

It must be stamped on the general layout plan; in most cases, the strength calculation sheet and design change orders are also stamped. If you don’t put it on, then how will others know that it was produced by the design firm? If you don’t provide it, others will consider it to be something verbal; if you do provide it, they will regard it as something written. In situations where it must be provided, verbal forms will not be accepted by others.

The manufacturing unit makes changes in accordance with the written documents from the design unit, and updates the general layout accordingly. The design layout plan has the design seal on it; just work based on that layout plan. Date changes are acceptable before the device’s date of manufacture; after that date, approval via a stamp from the original inspection agency is required. As for whether to stamp the department seal or something you mentioned, it doesn’t really matter.