How should gas-flushing time and gas ratio be verified on a commercial tray MAP machine?

Fix the chamber volume and residual-oxygen target first, then verify evacuation, gas filling, holding time and valve sequence on the tray MAP machine. Have the supplier run representative material and log the process data, capturing both average performance and abnormal samples, since a good average can hide unstable gas-flushing. Where several models look alike, compare measured application data rather than motor power or nominal speed. Tie each requirement to a measured result instead of a simple pass mark.