Henderson has little interest in fancy titles, big payrolls or marketing plans. His business card identifies him as Minewise Technology Ltd.’s technical manager – not president -reflecting his passion for hands-on problem solving and probably his humility as well.
“We’re only five employees, so we tend to do very niche work,” he said. “Others wouldn’t want to put the engineering into specialty stuff, so they come to us to work with them.”
Minewise Technology is particularly proud of its achievements in three key areas: ventilation-on-demand (VOD), the deployment of video in challenging underground applications and keeping diamond drillers at a safe distance from spinning drill strings.
While other ventilation-on-demand suppliers were touting their expertise and accomplishments, Minewise Technology quietly went about designing and installing a state-of-the-art VOD system at Vale’s Creighton Mine using RFID tracking technology on some 60 pieces of mobile equipment.
In the process of designing the system, Henderson abandoned the conventional approach of installing tags on mobile equipment and exciters at choke points and, instead, came to the conclusion that it made more sense to do just the opposite.
At Creighton, the tags are mounted in stationary locations in the mine, while the exciters have been hardened for mounting on the mobile equipment.
“We inverted it and found it to be much more effective,” said Henderson.
He also came to the conclusion that variable frequency fans aren’t always necessary or justified in ventilation-on-demand deployments.
“A lot of people view ventilation-on-demand as synonymous with VF drives and that you have to have VF drives to get any benefit from it. We found at Creighton that it’s not true. Turning fans on and off based on the position of vehicles works very well. You don’t need a VF drive for a 50 horsepower fan.”
Minewise Technology solved another ventilation-on-demand challenge associated with load-haul-dump machines, which typically traverse several ventilation zones while going back and forth from the heading to the ore pass. Normally, the fans would turn on or off as a loader proceeds through every zone, but that’s impractical. Minewise programmed the system to distinguish between a loader and a bolter, for example, ensuring that the fans remain on throughout the load-haul-dump operation.
Henderson also uses the tracking technology at Creighton to automatically turn on a water spray system for dust suppression during mucking operations and touts its effectiveness as a traffic management system for ramp haulage. Using Wi-Fi and monitors in the cabs, drivers can pinpoint the location of trucks ahead of them and either pull off to the side or continue on.
“They try to do it over the radio now, but it’s cumbersome,” he said.
Minewise Technology has also found a niche in video for radio remote control operation of underground mining equipment and for inspecting boreholes and raises.
Following a fatality at Vale’s Stobie Mine in 2006, operator stations used for remote control mucking are bolted to the wall.
“That often puts the operator in a place where he can’t see properly, so he needs video,” said Henderson. Minewise Technology installs video systems with cameras on the LHD and attached to the wall near the heading to provide the operator with a clear view of the muckpile and the bucket.
The company has also earned a reputation for using cameras with motorized reel systems to inspect boreholes and raises. In one application, Henderson worked with Orica Limited to clear a hangup in an 18-inch diameter borehole for roadbed material. An explosive charge was lowered immediately below a camera and detonated when the blockage was detected.
The camera died as a result of the explosion, but it was a small price to pay compared with driving a 600-foot alamack raise, which is what was done previously.
“Up to 1,000 feet is pretty straight-forward, but beyond 1,000 feet, it gets tricky,” said Henderson. “Mechanically and electrically, it’s more of a challenge. You just can’t hang a camera on a simple cable and expect it to function properly. We’ve gone down 3,600 feet and rigged up special equipment to do that.”
Drill string safety
More recently, Henderson designed and built an active monitoring system for Swick Mining Services to keep diamond drillers and helpers clear of rotating drill strings. Henderson used infrared motion detection technology to slow the drill string to a speed of 50 RPMs when rods are being changed and to otherwise trip the machine to zero speed when an intrusion is detected. Coming into contact with a drill string turning at 1500 RPMs can take off a limb or result in a fatality, he said.
“We shipped a system to Australia for assessment and had visitors from Newmont who were very interested in what they saw,” said Henderson.
Minewise Technology worked closely on the drill string monitoring assignment with another highly regarded troubleshooter in the Sudbury mining cluster, Paul Ballard, a hydraulics specialist with the Fluid Power House.
“We both share a common view that if you bring to bear various groups that have a specialty in a certain area, the sum of the parts is greater than the whole,” said Henderson. “We have worked with Paul on a number of projects. He does the hydraulics and I work on the control side. It’s a good model.
“A lot of people want to do it all by themselves, but it’s unrealistic to think you’re going to be successful that way.”
Focusing on niche projects is both a blessing and a curse, said Henderson.
“It’s a blessing in the sense that people want your expertise, but it’s a curse because it’s difficult to turn that into duplicate work.”