| 摘要 |
A rock drilling machine (11) is generating strokes to a drill stem by a thread connection. The adapter (12) has a bronze lining (20) that constitutes a female thread. The bronze lining (20) increases the life of the thread connection and is also detachable. Coupling sleeves (30) for an extension rod equipment can have similar bronze linings (20) as well as the drill bit. |
