Refiner plate with variable pitch

Abstract From the Canadian patent

A refiner plate for the face of a refiner disc comprising a plurality of refiner segments arranged side-by-side on the face of the disc to form a substantially annular refining region. Each refiner segment has an inner refining zone for receiving the material to be refined and an outer refining zone. The outer refining zone has a plurality of radially disposed bars defining an top surface and a plurality of radially disposed channels disposed intermediate the bars defining a lower base surface. At least one of the top surfaces has at least one radially extending groove defining a pair of blades and an intermediate base surface at the bottom of the groove. The intermediate base surface is …