Precision grinding of steel bar offers a defined tight tolerance on diameter, good roundness, straightness and a fine surface finish. The roundness and straightness of a ground steel bar ensures its suitability for machining in environments which require minimum vibration as the bars rotate at high speeds.
Size Range :
Centreless ground bar is manufactured in sizes between 6mm and 75 mm diameter.
Diameter tolerance and surface roughness :
| Diameter, urn max. mm special | Standard | Special Tolerance | Surface Tolerance | Surface roughness Ra urn, max. |
|---|---|---|---|---|
| 12-75 | ITS | IT 6 | 1.0 | 0.6 |
Lengths :
Bars are normally delivered in lengths between 3 and 6 metres. The delivery lengths for heat treated bar are different.
End condition :
Bars are normally delivered with the end surface cold sheared. We can also deliver bar with the ends cut square. Deburring or chamfering of one or both ends is available to special order.
Straightness :
| Diameter, mm | Straightness tolerance |
|---|---|
| 12-25 (25)-1 00 | 0.0003 x L* 0.0002 x L* |
* Applies to steel grades with a maximum hardness of 240 HB. The minimum gauge length is 0.5 metre.
Roundness :
Out-of-roundness, measured as the radius difference according to ISO 1101, is a maximum of one third of the diameter tolerance.