Regarding barometric pressure experiments
Thread Content
There has been a question bothering me for a long time: why isn’t a temperature correction made in barometric experiments? I’m a bit confused! I hope some expert can give me some advice
Using compressed air for testing carries certain risks; therefore, hydraulic pressure is generally preferred. Applying temperature corrections **increases the risk factor**.
By definition, the design pressure is the pressure that results in the thickest wall thickness and the highest pressure rating. The purpose of the experiment is to test the strength of the piping system under the designed conditions, particularly the weld points. Ignoring temperature, it’s essentially 1.15 times the normal-temperature experiment value; in fact, it’s even lower than the design conditions. Then isn’t this test just a formality?
Steel pipes leave the factory without being welded; this experiment is not primarily aimed at testing the pipe itself, but rather the welding strength
Temperature corrections are also taken into account in the pneumatic testing of pressure vessels; it’s unclear why they aren’t considered for pressure pipelines.
In winter, many installations in the north undergo pressure tests; hydraulic tests can easily cause pipes to crack from freezing