Seeking advice from experts familiar with on-site pressure testing of pressure pipelines

Clause 8.6 of GB50235-2010: Code for Construction of Industrial Metal Piping Projects

Inspect the pressure testing package, including the starting point and the ending point; pressure testing should be carried out separately before and after any change in the pipe grade. Generally, no equipment is used for pipe pressure testing – at least two pressure gauges are required, one at the lowest point and one at the highest point. The pressure difference resulting from the height difference should correspond to the gauge pressure. Gaskets must be installed on both sides of the blind flange, and the thickness of the blind flange must meet the requirements of the pressure testing pressure; otherwise, it is easy for the flange sealing surfaces to become deformed or damaged. The use of asbestos gaskets is not recommended. The pressure testing time should not be too long, as specified in relevant standards. Depending on the pipe material, the requirements for the water used in pressure testing also vary; generally, deionized water is required for stainless steel pipes, and the chloride ion content must meet relevant specifications. Pressure testing equipment typically includes electric multi-stage pumps and manual pumps, as well as water tanks; pressure is applied at the lower points while air is vented from the higher points. Since gas is greatly affected by temperature, it must be completely removed. There are too many other messy things; the more I write, the messier it gets. Look up relevant information, such as acceptance standards and the like

Also, pressure experiments are too dangerous, so they are generally not carried out

Isn’t a hydrostatic test carried out on-site? What if there’s a problem?

Atmospheric pressure refers to visual inspections, such as those for emissions and venting; pressure tolerance testing and airtightness are two different concepts