第12页外文翻译英文原文Belt Conveying Systems Development of driving system Among the methods of material conveying employed,belt conveyors play a very important part in the reliable carrying of material over long distances at competitive costConveyor systems have become larger and more complex and drive systems have also been going through a process of evolution and will continue to do soNowadays,bigger belts require more power and have brought the need for larger individual driv