| 摘要 |
<p>The core holder (4) has a receiving sleeve (1) and a core supporting pin (2) which is provided with a threaded bolt portion for screwing into a core sample (5). The core supporting pin is provided with a nut (2a). The receiving sleeve is provided with a coolant passage for drill bit (3), and a pin receiving bore for securely holding the core supporting pin against slipping out towards the core sample. An independent claim is included for hollow core drilling method.</p> |
