How to Measure a Ball Mill

The gold that lies in the Carlin Trend of Nevada consists of tiny particles trapped in complex ores. The ratio of ore to gold is 200 tons to 1 oz., and the first step toward extracting that ounce is to pulverize the ore in a ball mill. The business part of these contrivances is an immense steel cylinder containing steel balls. Chunks of ore are loaded in and the cylinder rotates. As the mix of ore and steel cascades against the cylinder's inner wall, the ore is broken into ever-diminishing pieces. Needless to say, this operation is tough on the mills as well as the ore. When the personnel at one facility wanted to find out if their mill had settled on its foundations enough to distort the machine frame and cause bearing misalignment, they brought in experts in the field of metrology and inspection services. And the experts brought in the FARO Laser Tracker. Using a laser beam reflected from a movable target placed on the equipment to be evaluated, the system measures points that lie within 115 ft. of the sending/receiving unit. A SuperADM feature lets the Laser Tracker reacquire an interrupted beam without returning to a reference point. The measuring "envelope" is ±360° horizontal and +80°/–50° vertical; point accuracy is 10 μm ±0.8 μm. After setting up the base tracker on a tripod, the operator touches or drags the target reflector along the surface of interest. The laser projects a beam onto the reflector and receives a split reflection. Using the angle between the beams and the distance to the target, the tracker's software triangulates and records the position of each point measured. Measurements at 40 points on the mill produced a digitized image accurate to ±0.005 in. that revealed most of the points to be within 0.040 in. of where they belonged.



Contact Darin Sahler, FARO Technologies, Lake Mary, FL; 407-333-9911, x-1137, [email protected], www.faro.com/s.

SENSORS EXPO & CONFERENCE

Sensors 2019 Hits Silicon Valley June 25-27!

Join 7,000+ engineers this June in San Jose at the sensor industry’s biggest event! With 65+ Technical Sessions, 100+ Leading Speakers, 10 new and updated tracks, and 300+ Interactive Exhibits, there’s more opportunity than ever to connect with this booming industry and the technologies driving it. See thousands of the newest technologies in action, learn about the latest applications, and develop invaluable partnerships at the only event dedicated to sensors, connectivity, and systems.

Suggested Articles

AC-powered linear position sensors operate continuously in demanding radiation environments.

Unique rotating-polygon design boasts safest, most reliable detection available.

North America’s largest tradeshow dedicated to sensors, IoT & connectivity welcomes innovators including Allegro MicroSystems, Honeywell, and Infineon to…