Product advantage: the shell is a cylindrical three section structure, and the use of large capacity of the tapered roller bearings, gear box with forced lubrication, effectively improve the bearing and the life of the. The gearbox forced lubrication system can be connected to the oil cooler and reduce the oil temperature inside the gearbox, and effectively enhance the reliability of the gear, bearing and oil seal. The gear box in addition to reverse a, other gears used synchronizer gear. Among them, 2, 3 files by molybdenum spraying double cone synchronizer. In addition to a reverse gear, using helical gear, large arc tooth design, and the use of powerful shot peening.