PSV and Rupture Disc force calculation (based on API RP 520)

Pipemill: for the design, analysis and layout of piping components

Force calculations for the initial or ‘pop’ condition and under sustained flow may be carried out for gas and vapour PSV’s (pressure safety valves) discharging into a closed header, or directly to atmosphere.

Rupture disc forces for gas or vapours can also be calculated.

Design input

  • Fluid characteristics (pressure, molecular weight, etc.)
  • Pipe dimensions

Analyses output

  • Reaction forces (kick forces) present in a liquid relief valve and a rupture disc may be calculated, for the initial and sustained conditions.
  • A warning and alternatives are provided (marked in red, right, bottom) due to the following: as gas flow approaches and exceeds sonic (Mach) velocity, the API equations will tend to predict higher PSV reaction forces than would exist if flow were limited to Mach speed.

Analysis support

  • Example analyses
  • Integral database of commonly available pipe sizes, with automatic input of selected pipe data
  • Explanatory notes and comments on API 520
  • Scientific calculator
PSV/rupture disc calculations - inputPSV/rupture disc calculations - output


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