METHOD AND DEVICE FOR DRILLING MUD REMOVAL FROM HOLE Russian patent published in 2006 - IPC E21B10/44 E21B49/00 

FIELD: mining, particularly to drill blast holes along with drilling mud removal by compressed air.

SUBSTANCE: method involves transporting drilling mud to land surface by supplying compressed air to hole bottom through central drilling rod channel and flushing channels of drilling bit and then delivering compressed air and drilling mud to hole annuity; separating compressed air flow into two flows with equal flow rates in drilling rod, which creates bottom, screw zones and hole annuity; moving the first compressed air flow directly to hole annuity; delivering the second compressed air flow to bottom zone and supplying drilling mud and compressed air mixture from bottom zone to screw zone and then to hole annuity; mixing the first compressed air flow with above drilling mud and compressed air mixture; displacing drilling mud from screw zone by means of screw and compressed air; conveying drilling mud from hole annuity to hole head by compressed air energy, wherein the drilling mud and compressed air mixture is injected by the first compressed air flow at the border of screw zone and hole annuity. Drilling mud concentration is regulated in all above hole zones and in hole annuity by compressed air parameter change with the use of control mechanism. Device comprises drilling rod having smooth-wall stems and screw removing starter having central compressed air supply channel, which supplies compressed air to bottom zone. The drilling rod is provided with upper and lower conical members, which create diffuser and contraction parts along with hole walls. The diffuser and contraction parts are adapted to eject drilling mud and compressed air mixture. Lower conical member is connected to drilling bit, upper one is connected to end stem. Upper conical member has ejection channels and is provided with control mechanism, which divides compresses air flow and regulates compressed air flow parameters.

EFFECT: increased efficiency of drilling mud evacuation and reduced unit costs for hole drilling due to decreased compressed air consumption, reduced costs of drilling rod production and repair and provision of compressed air properties adaptation to hole cleaning conditions.

6 cl, 9 dwg, 3 tbl