| 摘要 |
A boring head for reaming a pre-drilled hole in raise boring or for similar earth cutting operations comprising a plurality of roller cutters (13-22). For purposes of extending the radius of the boring head (10) in operation or decreasing its dimensions during transport one or several extension elements (36, 37) are provided for detachable attachment to the boring head (10) by means of a wedge connection (42). |
