December 15, 2008 - An ABB revamp of a shovel excavator at a Lafarge cement quarry in Germany cut the machine's energy consumption by 15 percent and extended the service life of this key piece of heavy-duty mining equipment by 15 years. The Lafarge cement plant and quarry at Karsdorf, Germany is the biggest and most modern cement plant in central Europe. ABB’s System 800xA controls the site’s entire cement manufacturing process. Excavator reconstruction improves efficiency, productivity and safety ABB replaced aging electrical components with a compact, state-of-the-art DC drive system that uses the existing DC motor and fits into the confined space of the excavator machine room.
Measurements conducted on site show that as well as extending the life of the equipment, the revamp has reduced energy consumption by 15 percent – a savings worth about $7,000 a year in reduced operating costs for this kind of small excavator. The 22-year-old shovel excavator at the Lafarge cement plant and quarry in Karsdorf, Germany, is one of four such machines that load raw material into a mobile crusher for processing in the adjoining cement plant. The revamp has increased the aging shovel's availability and productivity by eliminating production stops and the need for daily maintenance. Safety – a major issue for an open-pit mine where heavy equipment is in constant operation - has also been improved by the brake control and emergency stop functions built into the ABB drive system.
The results were such a success; Lafarge has equipped a second shovel excavator at the site with the same energy-saving, equipment-prolonging ABB solution. The alternative is to buy a new excavator, and they can cost up to $1 million each. Based on ABB’s industry-leading DCS800 drives, the LaFarge solution incorporates an ultra-compact high voltage transformer, System 800xA AC800M controllers, as well as an active rectifier for dynamic reactive power compensation to stabilize the excavator’s effect on the site’s power network.
The solution is designed to operate in a physically demanding environment of dust, damp and heavy vibrations and to withstand temperatures of between minus 25 and plus 40 degrees Celsius. (-13 F to 104 F) ABB is a leading provider of power and automation solutions for mining equipment, including giant excavators and walking draglines, as well as crushers, stackers, reclaimers and conveyors.