Abstract
Diavik Diamond Mine is following the industry trend of introducing automation into production through means of automated drilling to increase safety and efficiency. Incorporating full-fan autodrilling (FFA) in an operation increases the focus on safety by limiting the time operators spend in active work headings where they are subject to various hazards such as noise, vibration, dust, moving components and proximity to open holes. The corresponding positive impact to an operation’s schedule due to the potential for increased productivity directly influences cost savings in many ways including time, increased accuracy in tracking and flexibility.
As with any significant change in a workplace, achieving FFA has been met with many challenges from both a personnel and equipment perspective. Resistance to change, design modifications, and communication have been identified as impediments in personnel elements of achieving FFA. From the equipment perspective, maintenance requirements for older drills, limitations in system parameters and restrictions in unfavourable ground conditions have also attributed to the delay in achieving continuous FFA.
Various solutions have been implemented to overcome the above-mentioned barriers. Each boom on our Epiroc M6 drills is planned to undergo a complete rebuild to increase accuracy when maneuvering and setting up each hole’s memory for autodrilling. Drill designs have been altered in response to limitations posed by the FFA feature to optimize drill configuration and minimize drill movement. Rings in longhole stopes were changed to a split burden design to allow for fewer collars in each ring. This is favourable for FFA and avoids the risk of misreading holes due to tight collar spacing. Drill holes were also offset from the center/reference line to allow for a single drill set up on each ring, which is a requirement for FFA.
Communication has been identified as one of the most critical components of the FFA implementation. Drill Champions on each crew spent more time training with Epiroc representatives with the intent for them to then provide guidance to other drillers. Cross-training has proved to be difficult as labour is often not in abundance. More detailed shift reports were requested to include specific problems encountered while applying FFA, reasons why FFA was not applied, and comments/opinions on the application of FFA based on site-specific drilling conditions.
Unfavourable ground conditions remains one of the greatest limitations in implementing FFA at Diavik. Due to the nature of Kimberlite, certain areas of the mine consist of softer rock that can act like mud and require more effort as holes often require cleaning, deviate more, or cut to a larger than designed diameter. Autodrilling is difficult to use in these areas as even though reports are generated to illustrate conditions encountered, the feature is not able to account for these variables.
While achieving full-fan autodrilling has not yet become a reality at Diavik, a myriad of beneficial modifications on both an operational and technical level have resulted from efforts to advance the initiative.