Wexco inlay to screw material compatibility guide

There are a substantial number of different feed screw constructions engineered to meet process environment demands. The most popular options include flight land hard surfacing such as Stellite (6 &12), Wall Colmonoy (C56, 57, 83, 88) or similar PTA and spray weld applied materials. Other alloys include machine grade tool steels that are through hardened, nitrided, heat treated, flame, induction, precipitation or age hardened. In most all cases the screws base metal is hardened, coated or otherwise treated to enhance hardness and wear durability of the flight land and root. It is the responsibility of the screw manufacturer to achieve the appropriate flight surface hardness necessary to prevent galling between the barrel and screw.