ISA RP75.23 : 1995

1 Scope
2 Purpose
3 Definition of terms
4 Nomenclature
5 Overview
6 Cavitation index and valve scale effects
     6.1 Application dependencies
     6.2 Equations for scaling the cavitation
          coefficients
7 Applications
     7.1 Method
     7.2 Valve information
     7.3 Operating levels
     7.4 Considerations for selecting cavitation limits
     7.5 Cavitation-resistant valve designs
     7.6 Examples
8 Testing
     8.1 Scope
     8.2 Test system
     8.3 Test fluid
     8.4 Test procedure
     8.5 Data evaluation
     8.6 Laboratory qualification
Annexes
A - References
B - Cavitation fundamentals
C - Cavitation damage intensity and service life
D - Net pressure drop corrections
Figures
1 - Cavitation parameter plot
2 - Flow test system
3 - Cavitation detection equipment
4 - Cavitation calibration test manifold
B.1 - Cavitation scale effects
B.2 - Cavitation influences
B.3 - Typical flow curve appearance
B.4 - Flow curve appearance:two flowpath butterfly valve
Tables
1 - Numerical constants for cavitation equations
2 - Pressure scale effect exponent
C.1 - Range of estimated values of duty cycle factor, FDC

Designed for control valves used in control of process fluids, and not designed to cover fluid power components. Reader and user should be familiar with fluid mechanics fundamentals and ISA standards ANSI/ISA S75.01 and S75.02 on valve sizing and testing. Definitions of terms are meant for general understanding, more rigorous definitions are in the references. Noise measurement and prediction methods are not covered. Specifies state-of-the-art information about control valve cavitation. Includes information on cavitation parameters, methods of evaluating cavitation through testing, and guidelines for selection of valves.