| |||
| 钻头齿与井底接触面积; 钻头在井底覆盖面积 | |||
| 钻头牙齿与井底接触面积 | |||
| 井眼环形空间 | |||
|
hole coverage : 9 phrases in 3 subjects |
| Drilling | 4 |
| Oil / petroleum | 4 |
| Technology | 1 |
| |||
| 钻头齿与井底接触面积; 钻头在井底覆盖面积 | |||
| 钻头牙齿与井底接触面积 | |||
| 井眼环形空间 | |||
|
hole coverage : 9 phrases in 3 subjects |
| Drilling | 4 |
| Oil / petroleum | 4 |
| Technology | 1 |