Terminology for pressure vessels
1 Scope
This standard gives the basic technical terms widely used for pressure vessels.
It is applicable to the construction, installation, renovation, usage, etc. of pressure vessels.
2 Terms and definitions
2.1 General terms
2.1.1
pressure
force acting vertically on the unit area of an object, namely the pressure in physics
Note 1: The legal unit of measurement in China and the pressure unit in the International System of Units (SI) is Pa [Pascal], 1Pa =1 Newton per square meter, that is, 1Pa=1N/m2.
Note 2: It may be expressed by absolute pressure and gauge pressure according to different measurement criterion. Absolute pressure is the pressure measured based on zero pressure in absolute vacuum state, which is expressed by adding the letter “a” following the pressure unit. Gauge pressure is the pressure measured based on the ambient atmosphere pressure, i.e. the difference between the internal pressure of the vessel and the ambient atmosphere pressure, which is expressed by adding the letter “g” following the pressure unit. Unless otherwise specified, the pressure herein means gauge pressure during the construction and usage of pressure vessels.
2.1.2
ambient atmosphere pressure
atmosphere pressure of the location for placing pressure vessel
Note: Unless otherwise specified, generally, 0.1MPa(a) is taken as the ambient atmosphere pressure during construction of pressure vessel.
2.1.3
degree of vacuum
representing the rarefaction degree of gas in vacuum state, namely the absolute value of negative gauge pressure
Note 1: Pa is mostly used as the unit when constructing the pressure vessel.
Note 2: If the gauge pressure is negative, it indicates that the vessel is in vacuum state. The gauge pressure in full vacuum state is -0.1MPa(g).
Foreword i
1 Scope
2 Terms and definitions
Chinese index
English index
