Last year, we talked about how companies use it all around the world, in different mining applications. Now, we take the Autosampler underground.
The IMA Autosampler drill cuttings sampling, splitting and bagging device has found a new application in underground mining drills.
Underground blast and sampling holes are drilled with water flushing in which the material that comes out of the hole contains typically 90% water and 10% rock cuttings.
The first challenge is how to get a representative sample of that slurry because the high water content makes it difficult to collect the cutting and the water tends to segregate cuttings.
The second challenge is the working environment i.e the health and safety of the sampling personnel – sampling at the drill end in the “waterfall” is neither pleasant nor a safe job.
IMA has solved the sample representativeness issue with the Autosampler’s rotating distributor which spreads the wet cuttings evenly on a cone splitter with a sampling chute resulting in representative samples. The sample split ratio can be adjusted from 1% to 25%.
The wet samples are collected into longitudinal sock-type bags made of filter fabric. The fabric lets the water to seep through keeping the sample in the sock without losing fine particles with the water flow. The cuttings are collected from the hole collar by a funnel mounted on the boom front end. Drill cuttings are delivered to the Autosampler via a hose.
See below pictures of the Autosampler mounted on an Epiroc Cabletec drill in a gold mine.
Autosampler has chutes for 8 sample bags. Sample change is done by a remote control unit located in a comfortable and safe place in the drill operator’s cabin. Only after eight samples are taken the driller needs to go out to change for a new set of sample bags.
The remote control has also a by-pass function with which all the cuttings flow is directed to rejects passing the sample bags. This is to avoid excessive water entering the sample bag when starting the hole or when changing drill rods.
Further, with the remote control unit, you can start and stop the sampling function from the cabin at any time while drilling.