Yield Strength and Hardness
| API Grade | Yield Strength - Minimum PSI | Yield Strength - Maximum PSI | Tensile Strength - Minimum PSI | Rockwell C Hardness (est.) |
|---|---|---|---|---|
| H-40 | 40,000 | 80,000 | 60,000 | 0-15 |
| J-55 | 55,000 | 80,000 | 75,000 | 0-15 |
| K-55 | 55,000 | 80,000 | 95,000 | 14-25 |
| C-75 | 75,000 | 90,000 | 95,000 | 14-26 |
| L-80 | 80,000 | 95,000 | 95,000 | 14-23 |
| N-80 | 80,000 | 110,000 | 100,000 | 16-25 |
| S-95 | 95,000 | 110,000 | 110,000 | 22-31 |
| P-110 | 110,000 | 140,000 | 125,000 | 27-35 |
| Q-125 | 125,000 | 150,000 | 135,000 | 30-38 |
