ARRANGEMENT FOR FULL HOLE DRILLING

摘要

An arrangement for full hole drilling, wherein a drilling bit having a passage for drilling fluid is attached to a drill pipe string. A hole wall former is provided above the bit for closing the space between the hole walls and the drill pipe string. A container containing a plugging material is provided in the interior of the drill pipe string immediately above the bit, which is adapted to let drilling fluid between the walls of said container and said drill pipe string. The bit has an axial bore of a diameter which is greater than the inside diameter of the container and which is adapted to receive the lower end of said container.