Instrumentation specifically for the mining industry

April 5, 2016  1404  1404   

Ultrasonic sensors:

Ultrasonic sensors (also known as transceivers when they both send and receive) work on a principle similar to radar or sonar which evaluates attributes of a target by interpreting the echoes from radio or sound waves respectively.

Ultrasonic sensors generate high frequency sound waves and evaluate the echo which is received back by the sensor. Sensors calculate the time interval between sending the signal and receiving the echo to determine the distance to an object. Systems typically use a transducer which generates sound waves in the ultrasonic range, above 18,000 hertz, by turning electrical energy into sound, then upon receiving the echo turn the sound waves into electrical energy which can be measured and displayed.  This technology can be used for measuring: wind speed and direction (anemometer), tank and dam levels and air or water flow rates. For measuring speed or direction, a device uses multiple detectors and calculates the speed from the relative distances to particulates in the air or water. To measure the amount of liquid in a tank, the sensor measures the distance from the top of the tank, to the surface of the fluid.

Typical mining applications include:

• Monitoring and measuring of slurry/slimes dam levels;
• general level measurement;
• distance positioning and safety proximity sensing;
• crane positioning

Instrotech offers two ultrasonic devices, the SENIX LVL and SENIX TSPC30 

Wire-Actuated Encoders: (Draw wire Encoders)

Wire-actuated encoders measure distance (much like a tape-measure) showing the distance travelled, angles and position. These instruments can feature analogue outputs such as; potentiometer, mA current or DC voltage outputs, as well as incremental or absolute encoder outputs. Instrotech offers all of the SIKO range of encoders, but specifically the SGP, SG60 and SG120 which measure lengths of up to 6000 mm.

Typical mining applications include: 

• Furnace door position monitoring;
• Damper positioning;
• Hydraulic piston travel;

Electromagnetic Flow Meters: (Mag-flow meters)

The third instrument identified for specific mining industry solutions is the electromagnetic flow meter. The most common flow meter behind differential pressure and positive displacement flow meters, is the electromagnetic flow meter. A magnetic field is applied to the metering tube, which results in a potential difference proportional to the flow velocity perpendicular to the flux lines. The physical principle at work is electromagnetic induction. The magnetic flow meter requires a conducting fluid, for example, water that contains ions, and an electrical insulating pipe surface, for example, a rubber-lined steel tube.

Instrotech offers the KOBOLD range of flow metes in particular the Kobold model DMH which is specifically and robustly designed not to clog when dealing with dirty water containing small solids.
Typical mining applications

• Mine waste water and water treatment plants

For more information on Instrotech’s mining industry instrumentation, contact Instrotech on 011 462 1920, sales@instrotech.co.za or visit www.instrotech.co.za