Bucket-Wheel Excavators

Thursday, 19th April 2007 by

Continuing this week's theme of mining, today we're visiting Germany's lignite mining area to find some of the largest land vehicles on Earth!

Lignite (or "brown coal") is found in 3 nearby open cast mines in the Rhineland; Hambach, Bergheim and Garzweiler. Collectively they extract over 100 million tons of lignite every year. Extracting such massive amounts of coal requires massive machines -- hence the development of these descriptively named "Bucket-Wheel Excavators".

Their operation is simple; a large rotating wheel has numerous buckets around the rim - which scoop up the lignite (or soil), and then drop it onto a conveyer belt which runs along to the centre of the machine. A typical Bucket-Wheel Excavator could extract the area of a football field, 30m deep, in a single day's work.

Although the current World record for "largest land vehicle" is held by the RB293 bucket wheel excavator, the former title holder's story is much more interesting.

The story goes that Bagger 288 was the reigning champ in the large vehicle stakes, and operated at the most southerly Mine, Hambach. Here Bagger 288 worked away, happily removing the soil which covered the lignite, until 2001 when it had exposed all the coal and was to be re-located to the Garzweiler mine to the North.

However, rather than dismantling the $100 million machine and moving it in pieces, it was deemed cheaper to just drive the 200m long, 100m tall vehicle, 22 kilometres up the road to its new home!

Unfortunately that route happened to cross Autobahn 61, the River Erft, a railroad line and several roads... The whole process cost the equivalent of $10 million and took three weeks! This absolutely incredible photo taken during the operation gives you pretty good idea of Bagger 288's scale.

More pictures here and here. Wikipedia links for Bucket-Wheel Excavator & Bagger 288.

Thanks to Stefan, Graeme Wilkinson, Paul Burkitt-Gray, Chris, Darby & many other people!