Patent ID: 6119969
Filing Date: 2000-09-19
Classification: B02C,F23K,Y10S

Abstract:
In a mill in a coal-burning utility electrical power generation plant, said mill comprising a rotary drum for pulverizing coal, said drum being rotational about an axis and having a mill head at an axial end thereof, said mill head having a cylindrical mill head extension extending axially, a stationary cylindrical seal ring concentric with said mill head extension and defining an annular gap therebetween, a pair of axially spaced annular seals between said mill head extension and said seal ring and sealing said annular gap therebetween to prevent leakage of coal dust through said annular gap, a spacer between said seals and maintaining said seals in axially spaced relation, said spacer comprising an annular member substantially filling the entire gap between said mill head extension and said seal ring around the entire annulus thereof and preventing rolling movement of said seals into the annular interfaces between said spacer and said mill head extension and between said spacer and said seal ring as said mill head extension rotates relative to said seal ring.