DRILLING RIG FOR LARGE-SIZE HOLE DRILLING Russian patent published in 2008 - IPC E21B7/02 

FIELD: drilling equipment for deep large-size down-hole drilling in rock having variable rigidity.

SUBSTANCE: drilling rig comprises chassis 1 carrying pole 2 with cable 4 pulley 3, drive 5, drilling tool 6 and bailer 7 having opened upper end. The bailer 7 includes valve 8 and hook for suspension thereof. Pole 2 comprises rotation device 10 turned by means of drive 5 and installed to rotate drilling string 11 including drilling rods 12. Drilling string 11 is suspended to cable 4 through swivel 13. Rotation device 10 and swivel 13 are movably connected to guiding means 14. Rotation device 10 is connected to cable 15 through additional pulley arranged on pole 2. Bailer 7 has well tube 12. Upper end of bailer 7 well tube 12 is screwed on lower drilling string 11 end. Pneumatic hammer 17 with drill crown 18 is screwed on lower well tube 12 end.

EFFECT: increased drilling speed.

2 cl, 3 dwg