CBN Grit Applications

Grinding

1. Deep grinding saw blade teeth

High speed steel
64 HRC

Machine   = Tempo ECT502
Wheel speed   = 60 m/s
Grinding speed  = 4 seconds/tooth
Coolant   = 2 - 3% solution

ABN 360
US Mesh = 100/120
Resin bond
125  concentration

Increase in both efficiency and geometric precision

Tool life = 550 components

2. Grinding cylindrical cams into induction hardened camshafts

41 CrMo 4
55 - 58 HRC

Machine  = Kopp FK CNC
Wheel speed   = 60 m/s
Wheel size   = Ø 24.8 x 18 x 8 mm
Stock removal   = 0.3 - 0.4 mm
Coolant = 4 - 6% emulsion
ABN 800
US Mesh = 170/200
Vitrified bond
224 concentration

A 60 to 70% cost saving was achieved combined with a reduction in reject rates

Surface finish = 2.8-3.1 µm Rz

3. Duplex grinding of piston rings

Steel
100 HRB

Operation   = Surface grinding
Wheel size  = Ø 600mm
Stock removed  = 5 - 20 µm/pass
Wheel dressed with abrasive jet

ABN 360
US Mesh = 120/140
Resin bond
Wheel concentration ranges from 50 - 150
In 11 months 100,000 cm3
of material was removed

Production = 4000 rings/hour
Surface finish = 2 µm Rz

4. Continuous path jig grinding

01 tool steel, oil hardened to
60 HRC

Machine  = Moore G18 CNC
Wheel speed  = 25 m/s
Stroke rate  = 110 strokes/min
Coolant  = Semi synthetic oil

ABN 615
US Mesh = 200/230
Vitrified bond
150 concentration

Grinding time reduced by
15 to 20% due to fewer passes being required
Surface finish = +/- 2.5 µm

Honing

5. Honing the bore of an automobile speed gear

Hardened
carbo-nitride steel
65 HRC

Machine  = Jones & Shipman
Spindle speed  = 680 rpm
Stroke speed  = 400 strokes/min
Cycle time  = 40 seconds

ABN 600
US Mesh = 140/170
40 concentration
Single stage

Components can be finished in fast, mass production conditions with this tooling

Surface finish = 0.8 µm Ra

6. Multiple honing of crankshaft connecting rods

16 Mn Cr5 steel
61 HRC

Machine          = Gehring GR - 4000
Spindle speed  = 700 rpm
Feed rate = 20 m/min
Cycle time  = 77 seconds (per set)

ABN 300
US Mesh = 100/120
Multi-stick tool
Stage 1 of 3

Honing tool lives of up to 15,000 bores can be achieved under these conditions

7. Automated honing of vehicle fuel injection nozzles

High chrome tool steel
60 HRC

Machine  = Kadia multi-spindle
Spindle speed  = 1800 rpm
Feed rate  = 150 steps/second
Cycle time  = 28 seconds

ABN 600
US Mesh = 100/120
100 concentration
Stage 1 of 3

Multi-spindle machining enables batch production, high geometric accuracy and surface finish

8. Finish honing of hardened steel helical gear bores

20 Mo Cr4 steel
58 - 62 HRC

Machine          = Gehring multi-spindle
Spindle speed  = 60 m/min
Cycle time  = 78 seconds (per set)

Micron+ ABN
FEPA size = M40
50 concentration
Stage 3 of 3

Small diameter bores have been economically machined with high accuracy

Surface finish = 1.5 µm Rz