Pipe filter

A simple liquid does not count as a pressure vessel; only liquids that are protected by nitrogen or liquefied hydrocarbons qualify as pressure vessels. Does not meet the first criterion for pressure vessels: gases, liquefied gases with a pressure of 0.1 MPa (gauge pressure), and liquids whose maximum operating temperature is equal to or higher than their standard boiling point.

Whether equipment such as precision filters for organic Class C liquid pipelines constitutes a pressure vessel depends on the design parameters of the filter, such as operating pressure and operating temperature. According to **Standard GB 150 ‘Pressure Vessels’, a pressure vessel is a closed device that is subjected to pressure; it includes containers for storing gases or liquids, as well as heat exchangers, among other things. If the pressure at which the precision filter of such a pipeline operates is high and its energy content is also significant, posing a potential risk to the surrounding environment or personnel, it may be classified as a pressure vessel. This usually requires meeting some of the following conditions: – The internal operating pressure of the device is higher than the specified limit (in Chinese standards, this is typically above 0.1 MPa, that is, above atmospheric pressure). - The volume is generally greater than or equal to the specified limit (such as 30 liters). If the filter is small in size and both pressure and temperature are below the specified thresholds, it may not be classified as a pressure vessel. The most accurate basis for judgment is determined by the specific operating parameters of that precision filter, as well as the applicable **standards and industry regulations**. In practice, it is necessary to consult a professional pressure vessel inspection agency or obtain accurate classification information from the manufacturer. In China, the design, manufacturing, installation, use, and inspection of pressure vessels are all subject to strict restrictions and requirements set by relevant safety technical specifications. .

Classified in accordance with TSG 21-2016 \"Safety Technical Inspection Regulations for Fixed Pressure Vessels\"

I think it’s better to classify things according to the fixed capacity regulations; only those that have been classified and subjected to supervision and inspection should be considered valid

It is necessary to consider factors such as design pressure, diameter, and material comprehensively.

If neither the diameter nor the volume meets the conditions of the upper category, it does not belong to that category； When both the diameter and volume meet the requirements of the above category, if the operating temperature of the liquid is lower than its standard boiling point, it does not fall into this category; otherwise, it does.

It depends on the design pressure and the size of the container