Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
181 words
A process for finishing a metal workpiece without significant stock removal comprising rotating the workpiece about its axis while contacting the external surface thereof with the external peripheral surface of a circular finishing wheel having a peripheral speed from about 5000 to about 9000 surface feet per minute, characterized in that said finishing wheel comprises a dense molded non-cellular annular matrix having a circumferential reinforcing means, the radially outer portion of said matrix being deformable and being formed of a cured solid elastomeric polyurethane composition having a no-grain Shore A durometer hardness from about 30 to about 55 and a tensile strength of at least 4000 pounds per square inch and being capable of being elongated several hundred percent, said composition comprising a solid linear polyurethane which is the reaction product of a long-chain polyol having terminal hydroxyl groups and a molecular weight of at least 500 and an organic polyisocyanate having 2 to 3 functional isocyanato groups, said composition containing, per 100 parts by weight of said polyurethane, at least 50 parts by weight of finely divided abrasive refractory grains.
Claim 2
Dependent Claim
181 words
A process for finishing a metal workpiece without significant stock removal comprising rotating the workpiece about its axis while contacting the external surface thereof with the external peripheral surface of a circular finishing wheel having a peripheral speed from about 5000 to about 9000 surface feet per minute, characterized in that said finishing wheel comprises a dense molded non-cellular annular matrix having a circumferential reinforcing means, the radially outer portion of said matrix being deformable and being formed of a cured solid elastomeric polyurethane composition having a no-grain Shore A durometer hardness from about 30 to about 55 and a tensile strength of at least 4000 pounds per square inch and being capable of being elongated several hundred percent, said composition comprising a solid linear polyurethane which is the reaction product of a long-chain polyol having terminal hydroxyl groups and a molecular weight of at least 500 and an organic polyisocyanate having 2 to 3 functional isocyanato groups, said composition containing, per 100 parts by weight of said polyurethane, at least 50 parts by weight of finely divided abrasive refractory grains.
Claim 3
Dependent Claim
53 words
A finishing process according to claim 1 wherein the peripheral work-engaging surface of said finishing wheel has a diameter of at least 10 inches and said reinforcing means terminates about 1 to about 2 inches from said work-engaging surface, whereby the radially outer portion of said matrix is free to expand and deform.
Claim 4
Dependent Claim
35 words
A finishing process according to claim 1 wherein said finishing wheel is mounted on a centerless grinder having a rotatable regulating wheel which engages the workpiece and holds it in contact with said finishing wheel.
Claim 5
Dependent Claim
50 words
A finishing process according to claim 1 characterized in that said matrix is formed by curing a polyester or polyether urethane prepolymer having a viscosity at 212° F. of from 1500 to 6000 and has evenly distributed therein abrasive grains with a particle size from 60 grit to 320 grit.
Claim 6
Dependent Claim
101 words
A process according to claim 1 characterized in that said finishing wheel is mounted in an automatic grinder having feed means for causing relative axial movement between the finishing wheel and the workpiece at a predetermined rate of feed, said matrix is generally uniform and has distributed therein abrasive grains with a particle size no larger than 80 grit, and said finishing wheel is applied to a ground surface of the rotating workpiece having a surface roughness from 10 to 20 microinches, rms, to improve the surface finish and to provide a surface roughness not in excess of 5 microinches, rms.
Claim 7
Dependent Claim
40 words
A process according to claim 1 wherein said composition contains, per 100 parts by weight of said polyurethane, from about 50 to about 90 parts by weight of abrasive refractory grains having a particle size no larger than 80 grit.