Abstract: A removable rotating annular passage segment having a removable vane design is achieved by welding individual carbon steel parts into place. A welded passage segment having rails secured by a plurality of ribs is mounted to the grinding table of a pulverizer. Casted vanes are detachably mounted to the welded passage segment and are refitted when worn. The outer wall is adjustable and replaceable because it is welded to the pulverizer. Flow contour plates are welded to both the inner rail and outer wall.

Abstract: An improved annular passage arrangement for a pulverizer includes vertically extending inner and outer passage walls which define the annular passage divided by vanes extending at an acute angle to the horizontal. The annular passage is divided into a plurality of passage ports and a low pressure drop is experienced as compared to the prior art passage arrangements. The inner and outer passage walls may be connected to each other and rotate together with the vanes and the vanes are advantageously shorter in length then was conventional for further reducing pressure drop.