Hard-surfaced screw conveyor for centrifuges

A hard surfaced screw conveyor for centrifuges comprising:

• a helical metal blade mounted for rotation about the longitudinal axis of the helix and having radially disposed side surfaces extending to an end surface;
• a plurality of wear resistant segments mounted on a surface of the blade, said segment and said blade surface provided with mating parts wedged together to mount said segments on said blade and to permit movement thereof only in the radially inward direction toward the blade axis;
• keeper means retaining said segments against such radially inward movement;
• and
• said segments including a first set which are wider at their radially outer than their radially inner ends, and a second set intervening segments of said first set having a different shape with side edges parallel to the opposed side edges of the segments of said first set at opposite sides thereof, so that, upon removal of said keeper means, segments of said second set can be removed by sliding radially inwardly of said blade surface, and segments of said first set can be similarly removed after removal of a segment of said second set at one side thereof.