In April 2010 Wheales Environmental Ltd., a major UK-based crushing contractor, contacted Sandvik Mining and Construction for advice on problems with a mobile VSI crusher. Low production rates and maintenance downtime were the main issues causing Wheales problems in allowing them to meet their production contract with Lafarge Aggregates at their Toton Sidings distribution yard in Nottingham. The Toton site (Fig. 1) deals exclusively with rail ballast and had contracted Wheales to process rail ballast into a range of manufactured sand and aggregates.
After a visit to the site, Sandvik was quickly able to suggest a solution: the fitting of a Sandvik 85HP patented 2nd generation rotor and wear parts. Within days, the retrofit on the current VSI crusher was complete (Fig. 2). The actual conversion took no more than a couple of hours on site work, without any modifications to the crusher (Fig. 3). Results were both immediate and astounding. Production increased while maintenance downtime decreased and very troublesome vibration levels were completely eliminated. Previously an 8-h day production was averaging between 280-325 t of 0-5/5-20 mm and 500 t/d of Type 1 sub-base. Wheales Environmental immediately saw an increase with the Sandvik rotor of up to 745 t/d of 0-5/5-20 mm and 1100 t/d of Type 1. Also with the Sandvik rotor Wheales were able to operate the crusher for 150 hours before any rotor parts required changing.
• Material: granite (very competent Leicestershire granite from the Mountsorrell Quarry)
• Nominal feed size to the mobile VSI crusher (pre-screened): 20-63 mm
• Required products: 0-5 mm manufactured sand, plus 5-20 mm aggregate and also type 1 aggregate
• Post screened with Sandvik QA330 double deck screen unit (25 mm top deck and 5 mm bottom deck)
Sandvik Mining and Construction Central Europe GmbH, Joachim Sponholz, After Market Manager,
Tel. +49 174 3367-467, email@example.com, www.sandvik.com