Traditional agriculture machinery design have disadvantages of low efficiency and long design time.In this paper,the key parts of belt dryer(such as sprocket,heat exchanger and fan impeller) are taken as the research object for design based on the VB language using CATIA secondary development technology.The design method mainly took the parts built in CATIA knowledge engineering module as template,operated the template file through CATIA secondary development technology and builded the query system based on...