| Patent Number |
Title Of Patent |
Date Issued |
| 5259469 |
Drilling tool for percussive and rotary drilling |
November 9, 1993 |
| A drilling tool for percussive and rotary drilling in advance of a trailing casing tube (20) has a reamer (15) pivotally journalled and an eccentric shaft (12) rearwardly of a centric pilot bit (11). The reamer (15) has an eccentric portion (32) carrying axially directed hard metal butto |
| 5052503 |
Eccentric drilling tool |
October 1, 1991 |
| An eccentric drilling tool comprises a guide member (10) rotatably centered by the mouth of a casing tube (11) that follows the tool downhole during drilling. A pilot bit (23) on the guide member (10) is provided with axially oriented hard metal pilot button inserts (57, 57.sup.I -57 |
| 5040621 |
Flushing means for drilling tools |
August 20, 1991 |
| A flushing device for drilling tools comprises a guide member (10) carrying a drill bit (20) and being rotatably centered by the mouth of a casing tube (11) which is adapted to follow the drilling tool downhole during drilling. The drill bit (20) has a bit portion (22) that projects |
| 5009274 |
Laterally adjustable drilling tool |
April 23, 1991 |
| A drilling tool is followed by a casing tube (11) down the drilled hole. The mouth of the casing tube (11) centers rotatably a guide member (10) which receives rotation and impact energy via the interior of the casing tube (11). A drill bit (20) consists integrally of an axially protrudi |
