bucket-wheel excavator

A bucket-wheel excavator (BWE) is a continuous excavation machine used primarily in surface mining. It can remove large volumes of material, up to 12,000 cubic meters per hour. BWEs are most effective in soft, unconsolidated materials without large boulders. They are commonly used in lignite mining in Europe, Australia, and India, where they deposit overburden and coal onto conveyor belts for transport. In the United States, BWEs are sometimes used in conjunction with shovels or draglines to handle softer topsoil and clay layers. Trenching machines also utilize a wheel with buckets or a chain of buckets to dig trenches, piling excavated material to the sides. Bucket-wheel dredges are similar to cutter suction dredges but use a wheel excavator, making them better for harder materials and trapping heavy minerals.123