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Control valves

  • Calculation of the cv value, total flow or upstream and downstream pressures
  • Calculation of the installed flow characteristics with graphical optimization - including influence of reducers, viscosity correction and downstream resistance structures (silencers, ...)
  • Key Performance Indicator "Ri" (Reliability index). It’s the base of an expert system with detailed alarms, warnings and hints in order to improve the overall reliability of a valve solution for liquid, gas and steam applications.
  • Key Performance Indicator "Ci" (Controllability index): Prediction of the static controllability of a valve solution for the given control parameter by analyzing the installed characterstic of the valve. Includes graphical optimization und recommendation of the matching inherent characteristic for the valve comparing different options. Determining the best tuning point for the positioner.
  • Calculation of frequency-dependent sound pressure levels in accordance with the IEC 60534-8-3 (2010) and IEC 60534-8-4 (2015) for single and multistage trims.
    Noise calculation according to older editions of IEC 60534-8-3/4, ISA-75.17:1989 and VDMA 24422 editions 1979 and 1989 is still possible.
  • Influence of pipe reducers, viscosity and laminar flow.
  • Extended calculation of resistance structures (silencers, orifice plates, ...)
    • Design (automatic) CONVAL® calculates all intermediate pressures between the single resistances and optimizes them.
    • Design (specify pressures) Specification of the intermediate pressures and the subsequent calculation of the resistance structure
    • Recalculation (specify Cv) Recalculation of an existing single or multi stage multi hole orifice plate configuration
    • Analysis of the resistances of all operating points
    • Improved noise prediction for downstream resistance structures (Silencer, multi hole baffles) by a modified calculation according to IEC 60534-8-3 respectively IEC 60534-8-4.
  • Precisely mapping of standard valves thanks to a comprehensive library of valve modifiers (e.g. for double and triple eccentric butterfly valves...)
  • Direct selection of the valve from a manufacturer-specific valve database
  • Export to a data sheet (Excel) according to IEC or ISA.

Control valves with 2-phase flow at the inlet

Calculation and optimization of control valves with noise prediction and installed characteristics as described

Extended by options for

  • Calculation of liquids with vapor portion
  • Calculation of liquid/gas mixtures

Steam conditioning unit

Calculation for designing steam conditioning valves and the associated injection valve.

  • The required cooling fluid flow rate is first of all determined on the basis of the steam-converting valve,
  • and then a suitable injection valve is calculated taking account of the injection nozzle.

Aside of water, lots of additional fluids out of the thermodynamic module can be used to calculate a de-superheater

Actuator forces (Globe valves)

This program module calculates the forces that must be produced by actuators in order to guarantee reliable functioning of the control valve. The following actuator forces are calculated:

  • Min. closing force (closed position), Fs,0
  • Min. opening force (closed position), Fo,0
  • Min. opening force (open position), Fo,100
  • Min. closing force (open position), Fs,100
  • Min. stability force, FΔ (flow in closing direction)