TWO new Cat MD6420B Rotary Drills have cut their teeth on the overburden of Australian coal at Glencore’s Ravensworth mine in New South Wales. Production results for the first year of operation are beyond the industry’s ‘excellent’ rating of 6000 engine hours per year. The first unit, #112 (aka Judy) achieved a record level of 6876 hours and #113 (John) has come in at 7006 hours.
The results are unprecedented and are fully supported by Ravensworth’s maintenance summary reports which show the mean times between failures are 33.5 and 38.2 hours for the two drills, and the average repair durations are 1.9 and 2.3 hours. Mining managers’ expectations are about six hours.
Caterpillar product support representative – drills Andrew Elbourn says, “What this means is the MD6420B is a low maintenance drill overall. It self-monitors and diagnoses issues, which drives low MTTR (mean time to repair). The performance of these drills has been incredible. They just keep drilling.”
He says that with a maximum bit load force of 42,000kg and three different mast lengths to choose from, the MD6420B can drill holes as large as 311mm in diameter and as deep as 74.4 metres, making it ideal for high-production drilling in hard or soft rock applications. The rotary drill features heavy-duty structures, rugged components, a comfortable cab, convenient service access and many other attributes that reduce cycle time, improve productivity and lower ownership costs.
One example is the new operating system. The MD6420B has advanced controls and technology such as the control system that is ECM/CANbus, which is fully electronic with state-of-the-art user interface. Drill monitoring and diagnostics are displayed on a large touch-screen panel. History files detailing machine performance and health are downloadable. Advanced automation features include:
- Virtual Stops in upper and lower head positions
The control system also includes real-time machine health monitoring and built-in diagnostic tools that contribute to strategic service and maintenance planning.
Glencore Ravensworth North mine site is in the Hunter Valley and uses Cat equipment almost exclusively. The mine equipment is supported by regional Cat dealer Westrac under a maintenance and repair contract. Drills now operating at Ravensworth include two MD6420Bs, one MD6420A, two MD6290s and one SK40.