摘要 |
A method of fabricating conveyor or feed worms, especially those used in plastic processing machines, containing a tough steel core and a high wear resistant plating. Initially, there is fabricated a compound metal blank by forging or hot rolling a substantially rod-shaped steel core provided with a snugly bearing sleeve or sheath formed of the plating material while forming a metallic bond between the core and the sleeve and while reducing the sleeve diameter by at least 20%. After soft annealing the blank there is formed therefrom the worm profile, and then there is accomplished a thermal treatment which entails hardening and tempering in order to set the hardness of the plating material as well as the core material, and finally there is accomplished the finished machining to the final dimensions.
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