| 摘要 |
The invention relates to a start kit intended for drilling equipments for percussive rock drilling and of the type that comprises, on one hand, a starter rod (3) having front and rear threads, at least the front one of which is a male thread (5) and which have the purpose of allowing connection of the starter rod (3) with a drill bit as well as an extension rod, and on the other hand an enveloping casing tube (4), the inner diameter of which casing tube is greater than the outer diameter of the rod in order to provide an annular gap (24) through which flushing medium mixed with drill cuttings can be evacuated. In the casing tube (4), a front end wall (16) is included, which comprises, on one hand, a central hole through which a front part of the starter rod (3) provided with a driver (19) extends that has the driver (19) thereof situated behind the end wall (16), and on the other hand a number of peripheral openings (18) in order to allow flushing medium mixed with drill cuttings to pass into the annular gap (24). In addition, the invention relates to a starter rod and a casing tube as such. |
