Grinding and impeller clip for a coal pulverizer
The present invention is directed to, among other things, a grinding and impeller clip for attaching to a wheel assembly mounted for rotational motion within a grinding chamber of a coal pulverizer, wherein the clip has an arcuate cross sectional profile and a protective layer on its upper surface.
1. A grinding and impeller clip for attaching to a wheel assembly mounted on a center shaft defining an axis of rotation and configured for rotational motion within a process chamber of a material size reducing system, the clip comprising:
a) a clip body defining a base portion, the base portion being configured to facilitate the engagement of the clip body to the wheel assembly; and
b) an elongated wing portion, the wing portion extending outwardly from the base portion along a first axis and defining a length generally parallel to the first axis, the wing portion including upper and lower surfaces, wherein the upper surface includes a protective outer layer of a material having greater resistance to damage from the material size reducing system than another portion of the wing portion, wherein the cross section of the wing generally perpendicular to the first axis gradually reduces from at least one outer edge of the cross section toward the center of the cross section along the lower surface along a majority of the length of the wing portion.
2. A grinding and impeller clip as recited in claim 1 , wherein the base portion is substantially ring-shaped and defines a hole configured for receiving a fastening assembly to facilitate the secure engagement of the clip body to the wheel assembly.
3. A grinding and impeller clip as recited in claim 2 , wherein the base portion further comprises a recessed rim surrounding the hole for accommodating the fastening assembly therein.
4. A grinding and impeller clip as recited in claim 1 , wherein the protective layer includes protective tiles.
5. A grinding and impeller clip as recited in claim 1 , wherein the protective layer includes protective tiles fabricated of tungsten carbide.
6. A grinding and impeller clip as recited in claim 1 , wherein the elongated wing portion has a substantially arcuate cross section.
7. A grinding and impeller clip as recited in claim 1 , wherein the clip body includes Ni-Hard.
8. A method of forming a grinding and impeller clip as recited in claim 1 , wherein the clip body is formed by ductile forging.
9. A coal pulverizer having a grinding chamber and a center shaft defining an axis of rotation and configured for rotational motion within the grinding chamber, the coal pulverizer including a grinding and impeller clip for attaching to a wheel assembly mounted on the center shaft, the clip comprising:
a) a clip body defining a base portion, the base portion being configured to facilitate the engagement of the clip body to the wheel assembly; and
b) an elongated wing portion, the wing portion extending from the base portion along a first axis and including upper and lower surfaces, wherein the upper surface includes a protective outer layer of a material having greater resistance to damage from impact with coal particles than the wing portion, wherein the cross section of the wing generally perpendicular to the first axis gradually reduces from an outside of the cross section toward the center of the cross section along the lower surface along a majority of the length of the wing.
10. A coal pulverizer as recited in claim 9 , wherein the base portion of the clip body is substantially ring-shaped and defines a hole configured for receiving a fastening assembly to facilitate the secure engagement of the clip body to the wheel assembly.
11. A coal pulverizer as recited in claim 10 , wherein the base portion further includes a recessed rim surrounding the hole for accommodating the fastening assembly therein.
12. A coal pulverizer as recited in claim 9 , wherein the protective layer includes protective tiles.
13. A coal pulverizer as recited in claim 9 , wherein the protective layer includes protective tiles fabricated of tungsten carbide.
14. A coal pulverizer as recited in claim 9 , wherein the elongated wing portion has a substantially arcuate cross section.
15. A coal pulverizer as recited in claim 9 , wherein the clip body includes Ni-Hard.
16. A wheel assembly mounted on a center shaft of a rotary coal pulverizer, the wheel assembly including a grinding and impeller clip comprising:
a) a clip body defining a base portion and an elongated wing portion, wherein the base portion is operatively associated with the wheel so that the wing portion projects substantially perpendicularly from the plane of the wheel assembly along a first axis; and
b) wherein the wing portion includes a protective upper layer made of a material having greater resistance to damage from repeated impact with the coal particles than the wing portion, wherein the cross section of the wing generally perpendicular to the first axis gradually reduces from an outside of the cross section toward the center of the cross section along the lower surface along a majority of the length of the wing.
17. A wheel assembly as recited in claim 16 , wherein the wing portion of the clip has a substantially arcuate cross sectional profile.
18. The grinding and impeller clip of claim 5 , wherein the tiles are about three eighths of an inch thick.
19. The grinding and impeller clip of claim 12 , wherein the tiles are about three eighths of an inch thick.