Manufacturing requirements for pressure vessel flanges and nozzles
Thread Content
When a heat exchanger is used as a pressure vessel with cooling water in the shell side, is it necessary for the manufacturer to hold a license for handling special equipment when purchasing the nozzles and flanges for that shell side? Are inspection reports for the manufacturing of pipes and flanges required by the technical supervision department?
Pipes and flanges do not require inspection certificates; the same applies to sheets of metal, which only need a quality guarantee certificate and a compliance certificate. A head requires a supervision and inspection certificate by law, while an expansion joint can also have such a certificate, but it is not mandatory. Only steel plates specifically designed for pressure vessels require a special equipment manufacturing license. Steel that is not specifically designed for use in pressure vessels, such as Q235, is not required. Moreover, there is no such thing as a specification specific to pipe flanges for pressure vessels, so they also aren’t necessary.
However, some people on the forum mentioned that according to the new regulations, pressure vessel fittings require a manufacturing license for special equipment as well as supervision and inspection – how should this be understood?
Flanges with DN≥250mm are considered compressive elements, and the manufacturer must possess the necessary production qualifications