Capital Equipment News October 2017

Osborn has supplied a number of fine aperture screens in the past with no sizing issues.

Selecting appropriate screening technology to use in an application is absolutely critical to ensure the screen operates reliably and efficiently.

Scherf says, firstly, there is need to determine feed material size, which informs the decision between a primary and a final screen. “The second consideration would be the feed rate and media options to determine the size of the screen. And lastly, screen efficiency, screen accuracy, parts availability, service intervals and service friendliness to have the lowest cost per tonne should form part of the selection process,” says Scherf. Selecting appropriate screening technology to use in an application is absolutely critical to ensure the screen operates reliably and efficiently. Some of the factors to consider include material type, bulk-density, feed gradation, material top lump size, required cut size, clay content and feed-moisture. Based on these variables, OEMs need to consider design decisions, including required stroke, material travel rate, bed depth, deck load, wear protection, angle of inclination, spray water addition and other parameters. Know your application There are several typical screening applications, including classification, dewatering, heavy media recovery, scalping, trash removal and grading. Each screening application is suited to a certain type of screen, and it is important to choose the right screen for the job at hand. Scherf says grizzly feeders and scalpers (TK, VG, VF) are suited to fines removal at the primary station. They have a linear motion. “Scalping screens (Maxi scalp 600) are suited for fines removal at the secondary station or taking out hand stone. A product can be removed at this stage and, this creates capacity capabilities at the secondary crushing station. The scalping screen grizzly bars can also be replaced with tines for sticky material in recycling

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