Couplings are often used in the installation of mechanical equipment. Couplings are used as intermediate carriers to connect two shafts. They are widely used in petrochemical, metallurgical, electroplating and other industries. A mechanical part that rotates together and transmits torque. The two shafts must be separated by disassembly after the machine is stopped. There are many types of couplings, which can be divided into two types: fixed type and movable type according to the relative position and change of the axes of the two shafts to be connected. Most couplings have been standardized, and their structure, size and related design data can be found from relevant manuals. For non-standard couplings, the main reference materials can also be found accordingly. The purpose of using a coupling is to transmit power, compensate the relative displacement between the pump shaft and the motor shaft, reduce the installation accuracy and alignment requirements of the pump and the motor, ease the impact, change the natural vibration frequency of the shaft system and avoid harmful vibrations, etc. . The load category of the coupling in the transmission system is the basic basis for selecting the type of coupling. For working loads with large shock, vibration and torque changes, flexible couplings with elastic elements, that is, elastic couplings, should be selected to buffer, reduce vibration, compensate for axis offset, and improve the performance of the transmission system. The torque during frequent starting, positive and negative rotation, and braking is several times the torque during normal and stable operation, which is overload work, which will inevitably shorten the service life of the elastic element of the diaphragm coupling. The coupling is only allowed to be overloaded for a short time. The short-term overload shall not exceed 2-3 times of the nominal torque.

The coupling is installed between the driving side and the passive side of the power transmission to transmit rotational torque, compensate for installation deviation between shafts, absorb equipment vibration and buffer load impact, etc. One of the functions of the coupling is to absorb and compensate the deviation between the shaft and the shaft through its own deformation. The greater the flexibility, the stronger the ability to absorb deviations; the smaller the flexibility, the weaker the ability to absorb deviations. Generally speaking, this shaft-to-shaft deviation is divided into the following three aspects: The connection between the coupling and the peripheral equipment is realized by inserting the shaft of the equipment into the shaft hole of the coupling. The shaft hole forms of the coupling generally include keyway type, clamping type, clamping + keyway, top wire type, expansion type, etc. The keyway type is the most widely used, suitable for ordinary motors, ordinary reducers and ordinary transmission shafts. The clamping type is more widely used in servo motors, stepping motors, and various synchronous transmission shafts. The shaft and the hole are closely matched without any transmission gap. If an additional keyway structure is added, the torque transmission capacity can be enhanced. The top screw type is suitable for small shaft diameter and small torque transmission occasions, such as micro motors, encoders, etc.