IEC 60534-2-4 pdf download Industrial-process control valves – Part 2-4: Flow capacity – Inherent flow characteristics and rangeability 1 Scope This part of IEC 60534 applies to all types of industrial-process control valves. It defines how to state typical control valve inherent flow characteristics and inherent rangeabilities. It also defines how to establish criteria for adherence to manufacturer-stated flow characteristics....