As quarries seek to meet the growing demand for manufactured sand, vertical shaft impact (VSI) crushers are proving to be the ultimate solution due to their ability to produce high-quality manufactured sand. With a strong heritage in the design and manufacture of VSIs, Pilot Crushtec can meet production requirements by offering various VSI sizes with installed power ranging from 45 kW up to 315 kW.
Traditionally, cone crushers have been the preferred solution for sand production, says Wayne Warren, Africa Sales Manager at Pilot Crushtec. However, for a cone crusher to produce sand, it must operate on a very tight closed side setting (CSS), which makes it uneconomical due to excessive wear.
“A very tight CSS means the crusher operates on a liner-on-material crushing principle, which is not ideal because the wear rate increases dramatically and the product shape is generally poor,” explains Warren.
The VSI’s rock-on-rock crushing principle is more efficient for producing manufactured sand because it directly crushes the rock without intermediate crushing stages. “The VSI uses material-on-material crushing — the stone is accelerated at high speed into a rock box of the same hardness material, resulting in maximum breakage of the feed material,” explains Warren. “Depending on the speed, this can either achieve stone shaping with some sand production or, at higher speeds, a much higher percentage of sand.”
Charl Marais, Sales Manager at Pilot Crushtec, says a VSI’s ability to deliver consistent product grading makes it the ultimate crusher for sand making applications. “If a VSI is fed consistently, it produces a constant grading. In contrast, a cone crusher produces variable results because of liner wear. As soon as uneven wear patterns develop on the mantle and bowl liners due to intermittent feed conditions, grading consistency is lost,” says Marais.
Pilot Crushtec’s VSI range covers a wide spectrum of power outputs in three base models — the VS100, VS200 and VS350 — from 45 kW to 315 kW. These models offer five rotor diameters ranging from 600 mm to 1 000 mm and 14 different configurations to suit varying customer requirements.
