Back pressure at the diaphragm expansion vessel
The upstream pressure is the gas pressure as a function of the static pressure pst, the vaporisation pressure pD. The inlet pressure is greater than or equal to the sum of the static pressure pst, the evaporation pressure pD and a safety margin of 0.2 bar. The safety margin ensures that there is sufficient pressure at the high points. An inlet pressure of 1 bar is used for low static heights.
Note:
The determined inlet pressure must be lower than the specified final pressure pD through the safety valve by at least the closing pressure difference of 0.5 bar.
Symbol or abbreviation: | p0 |
Usual unit: | hPa |
| Equation: | p0=pst+pD+0.2 bar For low static heights: p0=1 bar |