Loss In Weight System for extruder

The loss-in-weight system type VDI/EE is a fully electronic weighing unit specially developed for continuous dosing of arbitrary products.
The loss-in-weight system is constructed to be extremely cleaning friendly, as the screw can easily be pulled out, and at the same time it is possible to loosen taper and scrapers inside the hopper.
The functional principle of a loss-in-weight is - through repeated static weighing – to determine a mass flow from a bin.
The weigh bin is slowly emptied, and the loss-in-weight per time unit gives the amount signal, which controls the dosing speed to the desired value.

The weight control WC9604 updates the proportion between the desired dosing and the actually dosed amount. When the bin is almost empty, it switches to the trend table, and the values just stored for proportion between screw rotation and weight loss, are used for calculation of dosing during refill of the bin. When the bin is almost filled again it switches back to normal operation.
The principle makes a very accurate dosing and very accurate mass flow regulation possible.