US 8,011,447 B2 · Automated drill string position survey

Abstract

A method of surveying drill holes, typically for use in underground mining situations where the holes are bored using a top hammer drill rig (10), utilizes a survey tool located adjacent the drill bit (1) which is used to log position readings as the drill string is withdrawn from the hole after the drilling operation. In this manner, it is possible to log the actual hole bored by the drill string (3) in real time as the drilling operation proceeds, and show deviation from intended hole positions (5) or (6). The survey tool typically includes an inertial survey package, a power source, and a data logger with the survey package selected from the group comprising commercially known inertial known survey packages, for superior characteristics of resistance to vibration and impact. The survey tool is maintained in a sleeping mode while drilling is undertaken, and activated to provide position data as the drill string is progressively withdrawn from the actual hole path (3).

Claims7

Dependent claims

A method of surveying drill holes comprising the steps of:

drilling a borehole with a drill string formed by a plurality of drill rods having a drill bit located at a cutting end of the drill string and being driven at least by percussive forces, wherein an inertial survey package is disposed within the drill string at the cutting end and advances with the drill string into the borehole while the drill string is operational to drill the borehole as part of a hole drilling operation, and wherein the survey tool is maintained in a sleeping mode while drilling is undertaken;
activating the survey tool once drilling is completed;
withdrawing the drill string from the borehole;
determining when the drill string is halted during the withdrawing of the drill string from the borehole;
and
taking position readings from the survey package as withdrawal of the drill string is temporarily halted to remove each drill rod from the drill string in response to determining that the drill string is halted during the withdrawal of the drill string from the borehole.

3 more elements

Dependencies are inferred from the claim text.

Automated drill string position survey

Life of this patent

Automated drill string position survey

Life of this patent

Abstract

Claims7