摘要 |
A rotary pulp refining disc has abrasion members secured therein by attachment means, such as welds, located in the thickness of the disc. In a preferred embodiment the abrasion members are parallel fins upstanding from a circular rigid plate and secured thereto by welds located in axially extending holes in the plate. These holes are filled with lightweight settable material after welding the fins to the plate. Upstanding pins can be provided at the periphery of the plate between the fins to constrict the pulp fibres. Two plates can be connected together in back-to-back relationship so that the refining disc can be inverted for reuse. <IMAGE> |