Ball Size, Grade and Tolerance Definitions
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ABMA Std-10
| Grade |
Sphericity |
Dia. Tolerance per Container/Lot |
Diameter Tolerance Per Shipment |
Surface Roughness, Ra |
|
Inches |
MM |
Inches |
MM |
Inches |
MM |
µinch |
µm |
| 10 |
0.00001 |
0.0002 |
0.00002 |
0.0005 |
±0.0001 |
±0.00254 |
1 |
0.025 |
| 15 |
0.00001 |
0.0004 |
0.00003 |
0.0007 |
±0.0001 |
±0.00254 |
1 |
0.025 |
| 25 |
0.000025 |
0.0006 |
0.00005 |
0.0013 |
±0.0001 |
±0.00254 |
2 |
0.05 |
| 50 |
0.00005 |
0.0013 |
0.0001 |
0.0025 |
±0.0002 |
±0.0050 |
3 |
0.08 |
| 100 |
0.0001 |
0.0025 |
0.0002 |
0.0050 |
±0.0005 |
±0.0127 |
5 |
0.125 |
| 200 |
0.0002 |
0.0051 |
0.0004 |
0.0102 |
±0.0010 |
±0.0254 |
8 |
0.2 |
| 300 |
0.0003 |
0.0076 |
0.0006 |
0.0152 |
±0.0015 |
±0.0381 |
n/a |
n/a |
| 500 |
0.0005 |
0.0127 |
0.001 |
0.025 |
±0.002 |
±0.050 |
n/a |
n/a |
| 1000 |
0.0010 |
0.0254 |
0.002 |
0.051 |
±0.005 |
±0.127 |
n/a |
n/a |
| 2000 |
n/a |
n/a |
0.005 |
0.127 |
±0.005 |
±0.127 |
n/a |
n/a |
| Burnishing |
n/a |
n/a |
n/a |
n/a |
±0.005 |
±0.127 |
n/a |
n/a |
ISO 3290
| Grade |
Sphericity |
Variation of Ball Diameter |
Variation of Ball Lot Diameter |
Surface Finish |
|
μ meters |
μ meters |
μ meters |
Ra |
| 3 |
.08 |
.08 |
.13 |
.010 |
| 5 |
.13 |
.13 |
.25 |
.014 |
| 10 |
.25 |
.25 |
.5 |
.020 |
| 16 |
.4 |
.4 |
.8 |
.025 |
| 20 |
.5 |
.5 |
1 |
.032 |
| 24 |
.6 |
.6 |
1.2 |
.040 |
| 28 |
.7 |
.7 |
1.4 |
.050 |
| 40 |
1 |
1 |
2 |
.060 |
| 60 |
1.5 |
1.5 |
3 |
.080 |
| 100 |
2.5 |
2.5 |
5 |
.100 |
| 200 |
5 |
5 |
10 |
.150 |
DIN 5401
| Grade |
Sphericity |
Variation of Ball Diameter |
Variation of Ball Lot Diameter |
Surface Roughness |
|
μ meters |
μ meters |
μ meters |
Ra |
| 3 |
.08 |
.08 |
.13 |
.010 |
| 5 |
.13 |
.13 |
.25 |
.014 |
| 10 |
.25 |
.25 |
.5 |
.020 |
| 16 |
.4 |
.4 |
.8 |
.025 |
| 20 |
.5 |
.5 |
1 |
.032 |
| 28 |
.7 |
.7 |
1.4 |
.040 |
| 40 |
1 |
1 |
2 |
.050 |
| 100 |
2.5 |
2.5 |
5 |
.060 |
| 200 |
5 |
5 |
10 |
.080 |
| 500 |
25 |
25 |
n/a |
n/a |
Ball Capability: Size, Grade & Material
| Material |
Smallest Standard Size |
Smallest Standard Size |
Largest Standard Size |
Largest Standard Size |
Best Standard Grade |
Least Standard Grade |
| Stainless Steels |
| 302/304 |
1.5mm |
1/16″ |
50.8mm |
2″ |
50 |
1000 |
| 316 |
1.5mm |
1/16″ |
50.8mm |
2″ |
50 |
1000 |
| 420 |
1.5mm |
1/16″ |
50.8mm |
2″ |
25 |
1000 |
| 430 |
1.5mm |
1/16″ |
50.8mm |
2″ |
100 |
1000 |
| 440c |
1mm |
1/32″ |
50.8mm |
2″ |
10 |
1000 |
| CorrTech Steel |
1mm |
1/32″ |
50.8mm |
2″ |
10 |
1000 |
| Other Materials |
| Chrome |
1mm |
1/32″ |
50.8mm |
2″ |
10 |
1000 |
| Low Carbon |
1mm |
1/32″ |
50.8mm |
2″ |
100 |
1000 |
| Brass |
1.5mm |
1/16″ |
25.4mm |
1″ |
200 |
1000 |
| Tungsten Carbide |
1.5mm |
1/16″ |
50.8mm |
2″ |
10 |
100 |
| Borosilicate Glass |
2mm |
3/32″ |
31.75mm |
1.25″ |
100 |
1000 |
| Soda Lime Glass |
2mm |
3/32″ |
31.75mm |
1.25″ |
100 |
1000 |
| Plastic |
| Acetal (Delrin and Celcon) |
1.5mm |
1/16″ |
25.4mm |
1″ |
G0 |
G3 |
| Nylon |
1.5mm |
1/16″ |
25.4mm |
1″ |
G0 |
G3 |
| Polyethylene |
1.5mm |
1/16″ |
25.4mm |
1″ |
G0 |
G3 |
| Polypropylene |
1.5mm |
1/16″ |
25.4mm |
1″ |
G0 |
G3 |
| PTFE (Teflon) |
1.5mm |
1/16″ |
25.4mm |
1″ |
G0 |
G3 |
