DRILLING SYSTEM AND METHODS OF DRILLING LATERAL BOREHOLES

摘要

A drilling system, comprising: a drilling machine (10) ,- a drill string (26) connected at one end to the drilling machine so as to be driveable in an axial direction; and a guide (30) connected to the drilling machine such that when the drill string is driven axially by the drilling machine, it interacts with the guide so as to be directed in a predetermined radial direction; wherein the drill string is permanently engaged so as to be slideable in the guide. A method of drilling a lateral borehole from a main borehole, comprises: positioning a drilling system as claimed in any preceding claim in the main borehole; anchoring the guide in the borehole adjacent the location at which the lateral borehole is to be drilled; operating the drilling machine to drive the drill string in an axial direction; and deflecting the drill string, by means of the guide, in a radial direction into the wall of the main borehole to drill the lateral borehole.