Sorry, I think my question wasn't clear and I still ask help.
I found a pressure vessel with the following data in its identification plate:
Design pressure: 17,5 kgf/cm2
Working pressure: 17,5 kgf/cm2
Hydrostatic test pressure: 28,1 kgf/cm2
Hammer testing pressure: 21,1 kgf/cm2
Me and my coleagues don't know what is the HAMMER TESTING PRESSURE. Note I didn't refer to the Hammer Testing (the percussion test) thati is an obsolete practice as is well known.
Again, I want to know what is the HAMMER TESTING PRESSURE (different from Hammer Testing) and where I can find more information about it.
Thank you