In 2018, Torque Africa surpassed its own previous percussion drilling record, achieving an impressive depth of 1402 meters. This groundbreaking project took place in Beaufort West, Western Cape, South Africa, where the team faced harsh weather conditions and stringent deadlines.
Despite these challenges, Torque Africa successfully completed the drilling project using a 140mm drill bit. The accomplishment not only demonstrated the team’s resilience and technical prowess but also reinforced Torque Africa’s position as a leader in the drilling industry. This new record stands as a testament to their ability to push the limits of drilling technology and deliver exceptional results under demanding conditions.
NARDUS BEZUIDENHOUT – Group director
Torque Africa has once again outdone itself, achieving a new drilling record of 1,402 meters at a mining project in Beaufort West. This significant milestone was reached through meticulous planning and execution, overcoming various challenges along the way.
Nardus Bezuidenhout, Group Director, detailed the project’s journey: “With the site layout completed and all drilling equipment in place, Torque Africa commenced drilling on 14 June 2018 using a Thor 8000 drilling machine.” Starting with an 8.5” drill bit, the team navigated through approximately 132 meters of clay and grey shale, facing additional challenges due to underground water yields.
“Bit changes at these depths are complex and can take up to 24 hours to retrieve the 6-meter rods for tooling replacement. A shanked bit would be catastrophic, potentially necessitating the drilling of a new hole if retrieval was impossible,” he noted.The team also faced challenges such as dolomite wetlands, dykes, voids, and water ingress at various levels. The hole was drilled telescopically, starting at 558.9 mm in diameter and reducing through various layers, including a 310-meter deep grouted section. Upon reaching 300 meters and intersecting quartzite, the diameter was down to 172 mm.The drilling continued until intersecting a stope at 1148 meters, slightly short of the predicted 1200 meters. At this depth, the bit size was 124 mm, ready to accommodate pumped products from the treatment of millions of liters of acid-mine drainage.
By 1 July, the company had successfully lowered its equipment to a depth of 706 meters, continuing to drill down to 747 meters. By 7 July, the team switched to a 152-140 mm bit and, through the implementation of two working shifts—day and night—reached 1,344 meters. The determined efforts culminated in reaching a final depth of 1,402 meters with a 140 mm bit. Retracting the drill string was also achieved with remarkable efficiency, showcasing the team’s adept handling of the project.
“This drilling phase was well planned and executed,” Bezuidenhout emphasized. Initially, the plan called for drilling to a depth of 700 meters. However, upon request from the client and involved entities, Torque Africa adapted and continued drilling for geotechnical exploration. Impressively, this extended drilling was completed within one month of the scope change, highlighting Torque Africa’s flexibility and capability to meet evolving project requirements.