Carbon steelballquality standards JB5301-1991
Scope: carbon steel ball bearings and other uses
units:μm
| Grade | Number of averagedia.deviation | Spherical error | Ball diameter variation | lot dia. Variation | Surface roughness | |
| Upper deviation | lower deviation | |||||
| 100 | 40 | -40 | 2.5 | 2.5 | 5 | 0.125 |
| 200 | 60 | -60 | 5 | 5 | 10 | 0.2 |
| 500 | 80 | -80 | 12.5 | 12.5 | 25 | — |
| 1000 | 100 | -100 | 25 | 25 | 50 | — |
Carbon steelballmachining precision between100G～1000G。
Production specificationsΦ1.5mm～Φ30mm
according to customer requirements to do other non-standard specifications carbon steel ball.
Carbon steel ball diameter selection table
| 公 称 | 直 径 | 公 称 | 直 径 | 公 称 | 直 径 |
| 1.5mm | 1.5000 | 17/64 | 6.7469 | 16mm | 16.000 |
| 1/16 | 1.5875 | 9/32 | 7.1438 | 21/32 | 16.6688 |
| 2mm | 2.0000 | 7.5mm | 7.5000 | 11/16 | 17.4625 |
| 3/32 | 2.3812 | 5/16 | 7.9375 | 18mm | 18.000 |
| 2.5mm | 2.5000 | 8mm | 8.0000 | 23/32 | 18.2563 |
| 3mm | 3.0000 | 8.5mm | 8.5000 | 3/4 | 19.0500 |
| 1/8 | 3.1750 | 11/32 | 8.7313 | 25/32 | 19.8438 |
| 3.5mm | 3.5000 | 3/8 | 9.5250 | 20mm | 20.000 |
| 9/64 | 3.5719 | 10mm | 10.000 | 13/16 | 20.6375 |
| 5/32 | 3.9688 | 13/32 | 10.3188 | 27/32 | 21.4313 |
| 4mm | 4.0000 | 7/16 | 11.1125 | 7/8 | 22.225 |
| 4.5mm | 4.5000 | 15/32 | 11.9063 | 29/32 | 23.0188 |
| 3/16 | 4.7625 | 1/2 | 12.7 | 15/16 | 23.8125 |
| 5mm | 5.0000 | 13mm | 13.000 | 31/32 | 24.6063 |
| 5.5mm | 5.5000 | 17/32 | 13.4938 | 25mm | 25.000 |
| 7/32 | 5.5563 | 14mm | 14.000 | 1吋 | 25.400 |
| 15/64 | 5.9531 | 9/16 | 14.2875 | 1-1/16 | 26.9875 |
| 6mm | 6.0000 | 15mm | 15.000 | 1-1/8 | 28.575 |
| 1/4 | 6.3500 | 19/32 | 15.0813 | 30mm | 30.000 |
| 6.5mm | 6.5000 | 5/8 | 15.875 | 1-3/16 | 30.1625 |