| 1. | Study on theory of drill rod with new type structure
一种新型结构钎杆的理论研究 |
| 2. | Welded drill rod and bit for low - compressive strength rock
焊接结构软岩钻杆与钻头 |
| 3. | Improvement on drilling rod of the cd - 360 drilling machine
360潜孔钻机用钻杆的改进 |
| 4. | Rotary drill rod used for coal mining roofbolter
煤矿锚杆钻机用回转钻杆 |
| 5. | Drill rod of raise boring machine for coal mine
煤矿用反井钻机钻杆 |
| 6. | Long service life percossive rock drilling rods
工业炸药和凿岩机发明后困扰世界采掘工业的百年难题 |
| 7. | Hollow hexagonal drill rods with taperd connection for rock drilling
凿岩用锥体连接中空六角形钎杆 |
| 8. | Rock drilling ; flush drills ; drill rod profiles , shanks and tapers
凿岩.冲击钻.钻杆截面.钻柄和锥度 |
| 9. | Hollow hexagonal drill rods with tapered connection for rock drilling
凿岩用锥形连接中空六角形钎杆 |
| 10. | Study on improving the service life of drill rods by magnetic treatment
磁处理提高钎杆服役寿命的研究 |
