Modern Mining September 2018

EQUIPMENT

results at Gamsberg project of the cutter is three times the nominal particle top-size of the solids with constant cutter travel through the stream.”

Another advantage is that the sampling spoon of the primary unit cuts the full stream of the slurry. The sampled slurry reports to the secondary vezin sampler where four cutters cut the full stream of the primary sample. The pri- mary sample is restricted via a conical insert at the inlet to the vezin sampler to ensure multiple cuts of the primary sample increment are taken. The primary cutter alternates its parked position between two proximity sensors, while the vezin’s cutters run continually through- out the primary sampling interval to ensure representative sampling. The unit also limits splashing when taking primary cuts, and the hood and cutter assembly are made of durable stainless steel with the drive units being splash- protected and dust-protected. Nyokong notes that Multotec’s single and double-stage vezin samplers conform to Theory of Sampling and Best Practice Cross- Cut Designs, with features that allow ease of access as the cutter can also be inspected and accessed via a large inspection cover on the top of the housing. In terms of the process control samplers sup- plied, Multotec’s gravity shark fin type sampler is designed to take a process control sample from a gravity, or non-pumped, process line or launder. The pressure pipe sampler is used to collect samples from pressurised lines. The gravity sampler uses the well-known technique of sampling via a static cutter and is recom- mended to improve sample representativity for all gravity line applications. The pressure pipe sampler is mounted into a Y-section with a carefully designed nozzle

inserted into the centre of the process pipe. This nozzle has an outlet which is aligned with the sampler so that a well-mixed sample is always drawn. Multotec has been supplying sampling solu- tions to the mining industry locally and abroad for over 30 years, with offerings including single-stage, double-stage and even triple-stage sampling systems. “Our custom designs allow us to meet the specific demands of customers’ applications while delivering practical engineering solutions and still remaining commercially competitive,” Nyokong concludes. 

‘Two In One’ sampler consisting of breathers (two on either side) to allow for primary cutter inspection and prevention of back pressure.

September 2018  MODERN MINING  47