The trial, carried out in June 2026 at Adelaide University’s Mawson Lakes campus, was the first time COBALT™ had been run with the RoXplorer® 1000 coiled tubing drilling rig. The tool was deployed and retrieved without incident, steered the hole as instructed and sent high-quality data from the bottom of the hole to surface in real time, all with zero non-productive time.
The trial forms part of Project 2 of the MinEx CRC programme, a collaboration between MinEx CRC, Adelaide University and AnTech, which aims to improve the sample integrity of coiled tubing drilling to match that of diamond drilling, while enabling multiple deviated holes to be drilled from a single pad. The ambition is to achieve up to 1,000 metres of reach, with the ability to drill to within 10 metres of a target and survey within 1 metre, while retaining the cost, speed, safety and environmental advantages of coiled tubing.
For AnTech, the programme is an opportunity to take coiled tubing drilling technology proven in the oil and gas industry and adapt it to the very different requirements of hard-rock mineral exploration.
A slim tool purpose-built for mining
At the heart of the system is AnTech’s 2-3/8" COBALT™, the company’s smallest directional drilling tool. Just 60 mm (2-3/8") in diameter, it was purpose-built for coiled tubing drilling in mining applications and is a scaled-down version of AnTech’s field-proven 3-1/8" COLT™ system.
COBALT™ combines steering, downhole measurement and communications in a single tool. Its Continuous Rotating Orienter (CRO), an electrically driven steering module, lets the driller make small adjustments to the direction of the hole while drilling continues, so the curved and straight sections of a hole can be drilled in a single run.
That matters in mineral exploration, where keeping a narrow hole on course and reaching a specific target underground can make or break the value of a drilling programme.
COBALT™ is also fully electric, with power and data carried by a cable running inside the coiled tubing. This means the tool can be controlled entirely from surface, while detailed information from the bottom of the hole is viewed in real time.
Delivering precise steering
The trial set out to prove two things: that COBALT™ could keep a hole vertical, and that it could then deliberately turn the hole and build angle in a controlled way. It achieved both.
The team first drilled without active steering, and the hole naturally drifted about four degrees off vertical. Once COBALT™’s steering was switched on, the tool brought the hole back to within 0.3 degrees of vertical and held it within one degree for the rest of the vertical section.
The team then began steering the hole away from vertical towards due south (an azimuth of 180 degrees), using a drilling motor with only a slight 1-degree bend.
With such a slight bend, and in soft, sandy ground, a sluggish response would normally be expected. Instead, the hole began to turn within three metres, building angle at an average of about 3.5 degrees every 30 metres. By the end of the trial, 692 ft (211 m) had been drilled and the hole had reached an inclination of 12.3 degrees. Drilling depth was limited to 250 metres by an underlying pressurised saltwater reservoir, and all drilling objectives were met within that limit.
These results show that the slim COBALT™ tool can actively steer a hole in a mineral exploration setting, rather than leaving it to drift as small-diameter coiled tubing holes tend to do.
All five trial objectives achieved
AnTech set five objectives for COBALT™ during the trial – and met every one:
Clear, real-time data from downhole
Steering is only part of what COBALT™ delivers. The tool also measures conditions at the bottom of the hole, giving the drilling team a live view of where the tool is and how drilling is progressing.
During the trial, COBALT™ recorded a full set of measurements including the load and turning force on the drill bit, natural gamma radiation from the rock, pressure, temperature, vibration and the performance of the steering motor. The data quality was excellent and was delivered in real time through the RoXplorer® platform, supporting both live steering decisions and post-run analysis.
Rather than treating steering and measurement as separate jobs, COBALT™ combines them in one tool, giving what AnTech describes as true drill-by-wire capability: the hole is steered from surface using live information from downhole.
Built for demanding conditions
COBALT™ is short and modular, making it quick to rig up and easy to configure for different jobs, and it is built to withstand harsh downhole vibration – borne out in the trial, where the tool came through the full run undamaged.
A platform for the next generation of mineral exploration
The Adelaide trial is an important step in showing how AnTech’s COBALT™ technology can help develop more capable coiled tubing drilling systems for mineral exploration.
By combining a slim tool, continuous steering and live downhole data, COBALT™ gives drillers what they need to control a hole and understand it while drilling.
For the MinEx CRC programme, the immediate challenge is to build on this capability and demonstrate that coiled tubing drilling can deliver the trajectory control, accuracy and sample integrity required for mineral exploration.
For AnTech, the trial shows that COBALT™ can bring advanced directional drilling and real-time downhole data to applications where conventional drilling can be slower, more costly or less flexible.
As mineral exploration moves towards drilling multiple targets from fewer surface locations, the ability to steer accurately, measure continuously and make informed decisions while drilling will become increasingly important. The COBALT™ trial at Adelaide University provides an early demonstration of what that future could look like.
For more information about AnTech and how we can help you with a future project, please email ctd@antech.co.uk.
