| 摘要 |
<p>1,067,975. Boring earth &c. SANDVIKENS JERNVERKS A. B. March 3, 1965 [March 10, 1964], No. 9088/65. Heading E1F. An adapter 23 for connecting a percussive drill (not shown) to a drill rod 11 and a casing 15 has a flushing head 34 rotatably mounted thereon, the arrangement permitting flushing fluid to be supplied to the space between the rod and the casing. Both the drill head and the casing have cutting inserts, and flushing fluid is supplied to the drill head through a duct 11a.</p> |
