Description: mean flow velocity through the valve opening area; Name: valve opening speed
Description: mean velocity of the flow through the valve spill area; Name: valve spill velocity
Description: The norm in fixed relation to the feature being described. This defines the parameters that influence the contents of the correlated feature. Type and number of the norm with issue year and issue month must be given, e.g. DIN ISO 4711:YYYY-MM.; Name: Reference norm material, pumping medium