what version of Conval software could size multi step restriction orifice plates. I already have version 9 but it could not find it.

 

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what version of Conval software could size multi step restriction orifice plates. I already have version 9 but it could not find it.

In CONVAL® 9, there is only the way to "abuse" the control valve module, as it has multistage orifice installations (single / multihole) as an option to be added downstream of the valve.
In CONVAL® 11, it's available in the restrictions orifice module as single/multistage - single/multihole option with lot's of features.