since 2005,tianshan heavy industry machinery co.,ltd cooperated with well-known corporations in china,such as chongqing gearbox,nanjing high accurate drive equipment manufacturing group co.,ltd,china national erzhong group co.,ltd and has exchanged technologies with well-known corporations,such as ge,siemens,gamesa and lomas,thus raising production level of gears,recently,this company has passed the evaluation and demonstration of some corprations like voith,bosch,david brown and moventas and has been regarded as eligible supplier by all of them.these years,changzhou tianshan heavy industry machinery co.,ltd is top annual "excellence suppliers" of chongqing gearbox,and only inspection exemption supplier in the history of china national erzhong group co.,ltd.