Coupling dynamic balance refers to the state where the centrifugal force deviates from the transmission shaft systems at both ends during the operation of the coupling. The precision index of coupling dynamic balance must be strictly controlled.

The dynamic balance accuracy index of couplings is stipulated by different standards according to different types of couplings. The manufacturing of this type of coupling requires the coupling manufacturer to use forged materials (with corresponding heat treatment) for integral processing as much as possible to avoid the deviation of centrifugal force caused by the internal structure defects (pores, sand holes) of cast steel materials.

The dynamic balance indicators of couplings can be tested on a dynamic balance testing machine and solved by counterweight, for example, the overall dynamic balance test of large intermediate shaft type gear couplings, etc. However, the key cause of the dynamic balance accuracy error of couplings lies in the manufacturing accuracy of the couplings. For instance, the selection of material types (forging materials and casting materials are different), the contact accuracy between coupling accessories (pins, connecting bolts, diaphragms) and the coupling body, and the improvement of the contact accuracy of each connected part of the coupling is a measure to enhance the dynamic balance accuracy of the coupling. For example, The contact states of the elastic pads of the XL star-shaped elastic coupling with the two halves of the coupling are different. The centrifugal force states generated during medium and high-speed operation are also different (reflected in the generation of noise and the different stability states of the transmission shafts at both ends).