CJD Equipment has enabled a gold mine portal expansion in Western Australia, modifying a Volvo ECR235E excavator to work underground with a rock grinding tool and all the trimmings.
The task was made unusually difficult by its underground nature and the limestone needing to be removed.
CJD key account manager James Daniels said a traditional method wasn’t going to cut it in this scenario.
“They had a new development on site where they essentially needed a new way of expanding their portal,” Daniels said.
“They couldn’t blast the rock because it was limestone, which would fragment and become unstable. Rather than do that they decided to grind away at the face and see how far they could get before they hit harder rock.”
The modified Volvo ECR235E excavator was chosen for its reduced swing radius which suited the tight, underground working conditions.
It was fitted with a dozer blade, a grinding wheel attachment, and a dust suppression system along the excavator arm.
Daniels says CJD has come to enjoy the opportunity to deliver interesting and effective machines.
“A large portion of our work is bespoke, and we’ve gotten it down to a fine art now, especially in underground mining. We’ve taken a strong hold of those responsibilities and do a lot of good, interesting work with those clients,” Daniels says.
“Our Guildford workshop team were instrumental in getting it together for us.”
Once the machine was chosen and basic design agreed upon, the client handed CJD a list of specifications to meet their needs for the mine. These included isolators, emergency stops and fire extinguishers.
While the ECR235E is already well kitted from the factory, with the case drain and both X1 and X3 hydraulic pumps standard on this model, CJD committed significant time into non-standard components.
A Simex rock grinding wheel supplied by Total Rockbreaking Solutions was the most important piece of the puzzle.
One issue, however, with fitting a grinding wheel to an excavator underground is adding dust suppression measures to a machine which typically wouldn’t come with this feature.
“We had to run a hose from the back of the machine with a valve on it, pass it through the cab to allow the operator to turn it on and off, and then run it all the way down the boom to the front where the grinding wheel was working,” Daniels said.
Another issue posed by the grinding wheel was the hydraulic capacity to keep it functional, which was made easier by the power offered by the excavator’s two-pump system.
All that was left to manage was the weight of the grinding wheel, as it presented overbalance problems and prompted extensive testing to ensure 360-degree stability.
To counter this, a dozer blade is fitted to the back of the excavator, which is used to leverage the machine into a level position, no matter the incline of the job.
Daniels said the testing was seamless and the client was impressed with the final product.
“We took it up to a site north of Perth where we were able to grind away at some rock and everybody was very impressed with it. The client had a number of people at the trial – their training and area managers and an operator,” he said.
“We even left it there over the weekend for the client to have a play around with. Their operator said it was fantastic and did everything they envisioned it would do.”
The operator has reported a quiet ride and ergonomic controls, both attributes Volvo prides itself on designing.