Vibration caused by unbalanced coupling

CouplingDue to various reasons, the center of mass or the inertial principal axis does not coincide with the axis of rotation, and the phenomenon of unbalanced centrifugal inertial force, centrifugal inertial couple force and dynamic deflection (vibration shape) will occur during operation, which is called the unbalanced phenomenon of the rotor. This kind of unbalance phenomenon will inevitably cause the vibration of the shaft system, thereby affecting the normal operation and service life of the machine, so it must be paid attention to.The degree of unbalance (unbalance U) is usually expressed by the product mr of the mass m of the rotor and the distance r from the center of mass to the axis of rotation of the rotor, which is called the product of mass diameter.It is also expressed by the product of mass diameter per unit mass, called the eccentricity e (not geometrically eccentric.) The product of mass diameter mr is a relative quantity related to the mass of the rotor, while the eccentricity e is a value that has nothing to do with the mass of the rotor. The amount of *.The former is relatively intuitive, and is often used for specific balancing operations of a given rotor. The latter is used to measure the pros and cons of the rotor balance or to check the balance accuracy. The balance grade standard of the coupling is evaluated by e.