When Cardan Shaft (Universal Joint Shaft) are operated at any angle greater than zero, the center section of the universal joint shaft always run irregularly, being accelerated and de-accelerated twice in every revolution. The maximum valves of mass acceleration torque arising here are dependent on the operating speed and angle of deviation and upon the moment of inertia of the cardan shaft section (RPM X ).

To ensure smooth running of the universal joint, especially at idling speed, the mass acceleration torque must not be allowed to exceed the limits shown in Table 1.

Speed Limit based on Lateral Critical Speed

In applications where long lengths of shafts are required, the speed is restricted by the lateral critical speed of the center section. This speed is a function of the center tube diameter wall thickness, and the effective length. The maximum operating speed must be less than the lateral critical speed Nc shown in Table 2.

Note :
Allowable Operating Speed = NC x 7.5.

In many applications, operation at 1/2 critical speed will also create unacceptable vibration. For these applications the operating speed should be 8% above or below 50% of the maximum indicated.

For flange-to-flange lengths greater than shown, or if allowable speed is exceeded, contact CARDAN INDIA.

Balancing

All standard universal joints under 300 RPM are supplied unbalanced. Between 300-850 RPM they are balanced if required. Consult factory for further information. Over 850 RPM all universal joints are normally supplied balanced. Please consult the factory for special balancing requirements.