UNE-EN 13136:2014

Foreword
Introduction
1 Scope
2 Normative references
3 Terms and definitions
4 Symbols
5 General
6 Pressure relief devices for protection of system
  components
7 Discharge capacities of pressure relief devices
Annexes
A (normative) Values of functions, factors and
                 properties of refrigerants
B (informative) Calculation of flow areas for
                 non-evaporating and evaporating liquids
C (informative) Example of calculation for sizing
                 pressure relief devices with the
                 corresponding pipes
ZA (informative) Clauses of this European Standard
                 addressing essential requirements or
                 other provisions of EU Directives
Bibliography

Describes the calculation of mass flow for sizing pressure relief devices for components of refrigerating systems. Describes the calculation of discharge capacities for pressure relief valves and other pressure relief devices in refrigerating systems including the necessary data for sizing these when relieving to atmosphere or to components within the system at lower pressure. Specifies the requirements for design and selection of pressure relief devices to prevent excessive pressure due to internal and external heat sources, the sources of increasing pressure (e.g. compressor, heaters, etc.) and thermal expansion of trapped liquid. Describes the calculation of the pressure loss in the upstream and downstream line of pressure relief valves and other pressure relief devices and includes the necessary data.