Diaphragm coupling equipment has key connection and tension sleeve connection, which can also be divided into cold fitting and hot fitting. The tolerance of the coupling that needs to be hot fitting requires excessively tight cooperation.There are three types of shaft-hole cooperation: transitional cooperation: there may be open space or interference cooperation between the hole and the shaft device.As shown in the figure below, the tolerance zone of the hole and the tolerance zone of uranium overlap each other; the second is the cooperation of the open space: when the hole and the shaft equipment, there is the cooperation of the open space (including the small open space equal to zero).The three are the interference cooperation: there is interference between the hole and the shaft device (including the cooperation where the small interference is equal to zero).In the process of machining and manufacturing, the cooperation of two or more parts can be roughly divided into sliding cooperation, transitional cooperation and tight cooperation, etc.

　　Coupling shaft hole interference cooperation is a kind of tight cooperation, which means that the matched shaft diameter (key width) is larger than the hole diameter (keyway). It is necessary to use extra materials to knead and enter, or use thermal expansion and contraction. Characteristic, heat the hole (keyway), take advantage of the expansion of the hole diameter, and sensitively sleeve it on the shaft. After cooling and shortening, the two parts are tightly integrated into one.The amount of interference is specified in the processing drawings.Assuming that some parts cannot be heated, the shaft (key) can also be cooled in dry ice, which has the same effect.If the coordination of the shaft hole tolerance is stricter, the looseness and tightness of the hole will affect the coupling equipment.