The coulter gear casing of changing speed is a major element of the machine of rotary tillage. The machine of rotary tillage is linked through the rear of the gearbox of walking tractor and the installation plane of this element, using two cylinders to sell location and 4 bolts to fix in order to realize the correct coupling of the machine of rotary tillage. The quality of the coulter gear casing of changing speed put a direct influence on the performance of machine. This design goes on the element analysis of the coulter gear casing of changing speed first, through the research and analysis of the bibliographical reference, then it have elaborated procedure and made the related contents such as technology; In technical route, it discussed machining surplus and the processing technology of casing, the process of the sequential arrangement and the calculation of the basic man-hour.

Keywords:  Procedure；the coulter gear casing of changing speed；location standard ； mental allowance