Description: Alphanumeric designation (starting with DN) of size for components in a piping system, used for reference purposes; Name: Nominal size socket/pipe
Description: Alphanumeric designation (starting with DN) of the size for components in a pipeline system, used for reference purposes; Name: Nominal size of nozzle/pipe
Description: variable quantity, which is not influenced by the control but is introduced into the control system from outside with the aim of making the final controlled variable follow it in a given relationship; Name: command variable