“Guangjing brand” concentric drill bit, with 40-year reputation guarantee, is produced with high-purity industrial diamonds and high-strength aviation alloys. Testes with over 120 drilling rigs, it is proved that the drill bit is a best option for sampling and coring of concrete pile foundations of high-rise buildings.
| Diameter(mm) | Inner Diameter(mm) | Grade | Lifespan | Speed | Concrete Grade |
|---|---|---|---|---|---|
| 101 | 83 | Red, optimized for life span | 150~180 meter | 10~15 minute per drill | C30，C35，C40 |
| 101 | 83 | Golden, optimized for speed | 110~140 meter | 7~12 minute per drill | C30，C35，C40 |
