美国久益采矿机械公司推出了世界上功率最大的长壁采煤机。这台７ＬＳ５型采煤机驱动功率为１９４０ｋＷ，特别适用于困难的开采条件。该采煤机最适用于回采２～４ｍ厚的煤层。第一台７ＬＳ５型采煤机于１９９９年９月在Ｓｈｏａｌ Ｃｒｅｅｋ煤矿投产。１ 可变速交流牵引装置 US long-mining machinery company introduced the world’s most powerful long-wall shearer. This 7LS5 shearer drive power of 1940kW, especially for difficult mining conditions. The shearer is most suitable for mining 2 ~ 4m thick coal seam. The first 7LS5 coal shearer was put into operation at Shoal Creek Coal Mine in September 1999. 1 variable speed AC traction device