Coupling during use may be some problems, such as the imbalance of the rotor.
Unbalanced centrifugal force during operation, the centrifugal force and even dynamic deflection (modes) of the phenomenon, known as the imbalance of the rotor.
Factors rotor imbalance are: asymmetric rotor body, manufacture and installation errors, uneven material. Rotor body asymmetry: should be addressed through a mass balance calculation increase with the design phase. Manufacture and installation errors, uneven material can only be found on a balance or equilibrium field to determine the size and orientation of the rotor imbalance, and thus should be added to determine the size of the radius of the mass balance and orientation, plus, minus the mass balance for balance.
Coupling may have corrected the imbalance main factors:
(a)coupling the accessory (a threaded connection, a key, shaft plate) caused by the uneven distribution or asymmetrical imbalance.
(b)generated by the coupling body parts (half couplings, etc.) design specification to manufacturing tolerances imbalance.
(c)from the surface of the eccentric shaft couplings (the cylindrical bore of the shaft and the concentricity of the outer edge) arising imbalance.
(d)by the coupling of the parts of the material or the uneven uneven wear unbalance.
(e)couplings with the gap between the parts.