High Speed Precision CBN Bore Grind Application



To reduce the cost of a CBN bore grinding operation by improving process efficiency.
Process: Grind the 39mm diameter bore in an Bearing Ring using vitrified CBN
Component: Ball Bearing Inner Ring
Material: 100Cr6 Steel
Hardness: 58 to 62 Rc
Stock Removal: 0.30mm (0.012")
Coolant: Water Soluble Semi Synthetic
Wheel Dressing: Rotary Diamond Dresser
Dress Compensation: 10 micron (0.0004")
Wheel Size: Type 1A1 - 33x22x10mm; 4mm CBN rim 1.300" x .866" x .394"; .160" CBN rim
Wheel Speed: 60 m/s (11,800 sfpm)
Wheel Specification: CB91-50JVI136
Grind Finish: 3um Rz (16 u" Ra)


Use of a Darmann engineered structure product resulted in:
Nearly double the parts per wheel (increased from 25,000 to 48,000 parts)
Reduced wheel and process costs
Improved cosmetic apearance of part as a result of cleaner grind