| Hardness Scale |
Hardness Range of The Standard Testing Blocks |
The Max. Tolerance of Hardness Display Value |
| HRA | 20~≤75HRA | ±2HRA |
| >75~≤88HRA | ±1.5HRA | |
|
HRB |
20~≤45HRB | ±4HRB |
| >45~≤80HRB | ±3HRB | |
| >80~≤100HRB | ±2HRB | |
| HRC | 20~≤70HRC | ±1.5HRC |
|
Hardness Value of Standard Testing Blocks (HBW) |
Tolerance of Displayed Value (%) |
Repetition of Displayed Value (%) |
| ≤125 | ±3 | ≤3 |
| 125<HBW≤125 | ±2.5 | ≤2.5 |
| >225 | ±2 | ≤2 |
| Tolerance of Displayed Value | Repetition of Displayed Value | |||
| Hardness Scale |
Displayed Value of Hardness Test Block |
Tolerance of Displayed Value |
Displayed Value of Hardness Test Block |
Repetition of Displayed Value |
|
HV30 HV100 |
≤250HV | ±3% | ≤225HV | 6% |
| 300~1000HV | ±2% | >225HV | 4% | |