ISO 21922 discusses refrigerating systems and heat pumps valves. Refrigeration systems operate on a series of consecutive thermodynamic processes that form a cycle that returns the working substance to the same state. ISO 21922 specifies safety requirements, certain functional requirements, and marking of valves and other components with similar bodies, hereinafter called valves, for use in refrigerating systems including heat pumps.
ISO 21922 applies to the design of bodies and bonnets for pressure relief devices, including bursting disc devices, with respect to pressure containment. In addition, ISO 21922 is applicable to valves with a maximum operating temperature not exceeding 200 °C and a maximum allowable pressure not exceeding 160 bar1.
ISO 21922 describes the procedures to be followed when designing valve parts subjected to pressure as well as the criteria to be used in the selection of materials and requirements for valves with extension pipes are included.
ISO 21922 describes methods by which reduced impact values at low temperatures may be considered in a safe manner.
Note: ISO 21922 does not apply to any other aspects of the design or application of pressure relief devices.
ISO 21922 on refrigerating systems and heat pumps valves is useful for:
All parts of the valve or valve assembly are designed and manufactured to remain leakproof and to withstand the pressures which may occur during operation, standstill and transportation, considering the thermal, physical and chemical stresses to be expected. ISO 21922 provides you with the safety requirements, safety factors, test methods, test pressures used, and marking of valves and other components with similar bodies for use in refrigerating systems. Following safety guidelines ensure that valves are safe for use and operation.
ISO 21922 guides you for the installation and operation of valve and valve assemblies. Following guidelines are given in ISO 21922 ensure the proper functioning of hand-operated valves and actuator-operated valves and also checks for other defects in the valves prior to dispatch.
Refrigerating system valves need to be manufactured from compatible materials. ISO 21922 includes requirements for materials to be used for pressure bearing parts and helps you with the selection of appropriate material for the valve.