Drilling Production

Drilling Production: Accuracy Holds The Key


When Jason Andrews looks out from the cab of a working rotary drill, he sees more than a pattern of holes on a mine site bench. As Application Specialist for Caterpillar, he can picture the impact the drilling operation will have every step of the mining process.

“Basically, the whole value chain kicks off with drilling,” Jason says. “Drilling impacts the entire site’s daily production. It determines how effective the blast is, which in turn affects how much secondary rock breaking you have to do, how easily the shovel can dig and how efficiently and fully each truck can be loaded. It even influences the energy consumption and production efficiency of the crusher.”

There’s a lot riding on the drilling operation, Jason explains, “because it all comes down to consistent fragmentation. When you do the drilling right, you’ll likely get a good shot and consistently sized material. That means, among lots of other benefits, that you can eliminate a significant amount of rock hammer work in the muck pile. We’ve seen mines cut hammer hours by more than 60% just by improving their blasthole accuracy.”*

Speed vs. Accuracy

In Jason’s view, drilling accuracy is a key to unlocking extra productivity across the site. “People think that drilling production is all about speed—vertical meters per hour—but you’re better off trading speed for accurate hole placement, depth and angle.”

Another key production factor to consider is hole quality. Jason says, “It’s one thing to drill a blasthole quickly, and it’s good if you can do that. But if it’s not a quality hole—if it caves in as the steel is retracted or if it collapses before you can place the charge—you haven’t really gained anything. You’re going to lose the time you saved because you’ll have to do a bunch of rework, so it’s a zero sum game.”

Applying Technology

So, how can a mine site improve its drilling accuracy without sacrificing meters-per-hour production? “Technology is making a big difference on that front,” Jason says. “The industry is moving toward drilling automation, which helps to build more consistency into the drilling process.”

He adds, “Even relatively basic technologies like the Drill Assist functions on the latest Cat® Rotary Drills can make a big difference in hole quality. It automatically collars the hole and controls the speed and pressure of the bit. That process consistency results in a hole that stands up well. An operator may be able to get the hole drilled faster, but it comes at a cost in hole quality, and it may cause a lot of extra wear and tear on the machine and bit.”

Jason adds that there are more drilling technology options available now than ever before. “It’s actually pretty easy to step into the digital mining realm with things like Cat Terrain for drilling. And once you take that step, you’ll never want to go back.”

Location And Depth

Cat Terrain for drilling brings satellite guidance and digital drill pattern planning to the table. Jason notes, “Cat Terrain kicks drilling accuracy way up. The system provides the guidance to make sure that all holes are drilled in the right place, at the proper angle and to the right depth.”

Research shows that Cat Terrain for drilling results in up to four time better pattern accuracy than manual hole placement, “and that makes a real, measurable difference in fragmentation consistency,” Jason says.

“Plus, Terrain automatically identifies the collar elevation when you’re working on uneven ground. It then calculates the depth for each hole to within 10 centimeters, so you don’t have any over- or under-drilling. You end up with a much smoother bench after the blast, and that helps with shovel and truck productivity.”

Autonomy And Equipment 

With the industry moving toward autonomous equipment systems, Jason predicts that drilling accuracy will improve even more in the coming years. “Caterpillar is offering a range of Cat Command semi-autonomous and autonomous drilling options. You’ll be able to tailor a system to your site’s needs and operating budget, and you’ll see immediate payoffs in production and cost efficiencies.”

Of course, no matter what technologies you apply, Jason admits that it will always be crucial to start with the best drilling equipment you can get. “If you’re going to keep operators in the cab, you’ll want to make sure you give them a comfortable, well-designed environment to work in. And if you go with an autonomous or semi-autonomous system, you’ll always want fast, stable tramming and high machine availability.

“Cat drills deliver all of those benefits,” Jason says. “And Cat automation technologies are deeply integrated into the machine systems for the smooth control and predictable operation. You won’t get that level of integration with third-party technologies.”

Invest In Precision

On any surface operation, no matter the size of the mine or what type of material is extracted, Jason concludes, “it always pays to invest in drill pattern accuracy and drilling process precision because those factors can make such a huge difference down the line.” 

As evidence, he cites a study that showed shovel gains of 9% as a direct result of improved drilling. “And we’ve tracked throughput gains of as much as 5% per year* in operations where poor fragmentation had been a problem. In an industry that’s scratching for gains measured in fractions of a percent, a result like that can be major game changer.” 


*source: http://www.saimm.co.za/Conferences/SurfaceMining2008/113-136_Amiel.pdf