As the first stage in a multi-level cleaning system, the primary cleaner removes the majority of material adhering to the belt, leaving only a thin layer of sticky powder.

The blade applies the appropriate pressure on the belt, allowing the sweeper to strip the adhesive material from the belt at a suitable fixed angle. Excessive pressure at this angle can damage the belt, belt fasteners, and the sweeper itself.

Primary sweepers are typically installed on the surface of the head roller, below the material flow. The construction and installation of the sweepers should avoid affecting the material conveyance and prevent material buildup.