BUP sheet metal testing machines
The VW test is a test method used for the determination of sheet metal forming properties.
In this test the waviness of flat steel products for the vehicle body exterior is tested with and without metallic coatings.
A Marciniak tool is used to draw a cup, up to a plastic strain between 5% and 10%. Depending on the material, drawing depths between 10 and 20 mm are generally attained. The punch diameter must be at least 120 mm.
The surface waviness of the cups is determined in connection with another measuring system (e.g. reference plane touch-probe system, optical line-measurement system or confocal microscope).