Rotary impact mill
View Patent ↗In one aspect of the invention, a rotary impact mill has a milling chamber defined by housing with an inlet, an outlet, and at least one wall. A plurality of impact hammers located within the milling chamber are fastened to and longitudinally disposed along a rotor assembly connected a rotary driving mechanism. At least one of the impact hammers has a body with a first hardness. The impact hammer also has a wear resistant insert bonded to the body, wherein the wear resistant insert comprises a hard surface with a second hardness greater than the first hardness.
1. A rotary impact mill, comprising:
a milling chamber being defined by a housing with an inlet, an outlet, and at least one wall;
a plurality of rectangularly shaped impact hammers fastened to and longitudinally disposed along a rotor assembly connected to a rotary driving mechanism;
at least one of the impact hammers comprising a body having a first hardness;
the impact hammer also comprising a plurality of wear resistant, rounded inserts, fixed within recesses formed in the body and protruding beyond a surface of an impact side of the body proximate a distal end of the body,
wherein the wear resistant inserts comprise a cemented metal carbide base segment attached to a distal end of the body and a hard surface comprises a layer of diamond or cubic boron nitride which is bonded to the base segment
wherein the rounded inserts comprise a substantially conical end protruding beyond an impact side of the hammer body wherein the conical end comprises a rounded apex.
2. The mill of claim 1 , wherein the body comprises steel, stainless steel, a cemented metal carbide, manganese, hardened steel, or combinations thereof.
3. The mill of claim 1 , wherein a proximal end of the impact hammer is fastened to the rotor assembly.
4. The mill of claim 1 , wherein the wear resistant insert comprises an axis that forms an angle with a line normal to axial length of the body.
5. The mill of claim 1 , wherein the wear resistant inserts protrude beyond the body by 0.100 to 3.00 inches.
6. The mill of claim 1 , wherein the wear resistant inserts are brazed or press fit into the recesses of the body.
7. The mill of claim 1 , wherein the wear resistant inserts are adapted to deflect debris at an angle.
8. The mill of claim 1 , wherein the layer is thermally stable.
9. The mill of claim 1 , wherein the layer is bonded to a non-planar interface with the base segment.
10. The mill of claim 1 , wherein the layer comprises a metal binder concentration less than 40 weight percent.
11. The mill of claim 1 , wherein the layer comprises a grain size distribution of 0.5 to 300 microns.
12. The mill of claim 1 , wherein the layer comprises a polish finish.
13. The mill of claim 1 , wherein the wear resistant inserts are bonded to an edge of the body.
14. The mill of claim 1 , wherein a distal end of the body comprises a distal surface opposite the proximal end and substantially normal to the axial length of the body, wherein the distal surface comprises a hard surface.
15. The mill of claim 1 , wherein a screen is disposed within the milling chamber and adapted to move in a different direction than a direction of the plurality of impact hammers.
16. The mill of claim 1 , wherein a wear resistant coating is bonded to a deflector located within the milling chamber.