Different character of powder's packing

Non-free flowing powders

The auger could fit with 'over-flight', this can be either a separate detachable component to provide ultimate flexibility, or can be part of the actual auger for dedicated applications.

An over-flight assists the flow of non free flowing products by providing compression into the auger flights, down to the neck of the funnel where the scraper blade feeds the flights of the parallel section of the auger.

Intermediate Powders

With intermediate products, an auger with parallel flights would be normally be selected and no over-flight fitted, as compression could well cause unacceptable damage to the product. These types of product often have the tendency to dribble from the auger once it has stopped and therefore require back pressure to be applied by use grid attachment to the bottom of the funnel.

Free flowing powders

Free-flowing powders require a positive means of cut-off to be fitted to the end of the funnel. This can be use a single double flap attachment (also fitted to outlet of funnel). Ensures a clean cut-off at the end of each discharge and prevents product dribble / seepage.

Spinner plate & Cowl

An alternative tooling option that usually would be fitted for handling particle type products is the Spinner plate & Cowl illustrated below.

Attached to the end of the auger is a spinner plate (disc), this is a saucer shaped disc designed to retain the product flow. All powders have an angle of repose, the angle at which a collapsing heap of powder will come to rest rather than continue to spread outwards. The angle for small smooth beads would be much greater than, for example, vermicelli. The distance between the bottom of the funnel and the spinner plate (the gap needed to allow unrestricted product flow) is defined by the product dose rate. The spinner plate is sized to prevent the powder dribbling over the rim of the disc once the auger has stopped, taking into account this gap and the powder's angle of repose. As the spinner plate throws the powder outwards, a simple collection cowl funnels it to a size suitable for the aperture of the container to be filled. The use of a spinner plate results in a perfectly clean fill without the requirement for any additional cut-off devices.