| 摘要 |
A drilling apparatus (10) for drilling boreholes in underground formations, comprising a tool body (10a, 10b) that can be positioned in a borehole where drilling is to take place, an oxy-fuel burner having a nozzle (16), a supply of a fuel (18) and a supply of an oxidising agent (20) connected to the burner; and means for advancing the tool body through the borehole as drilling takes place. |
