Choosing the right cardan shaft for your process involves several factors in consideration. These include- the load size, the transmission speed of the shaft, the accuracy of installing the two connecting parts, price of the shaft, the rotational stability, and many others. Another important factors that need to be taken into consideration is the type of coupling used.

Factors for consideration

When choosing a cardan shaft, you have to keep several points in mind. These are as follows:

• Direction and magnitude of relative displacement: It is often very difficult to keep two shafts in an accurate and strict alignment after the installation adjustment due to the changes in the temperature, load deformation and manufacturing. Often displacement happens in the skew angle CI X and Y directions. Sliding couplings are selected when the radial displacement is quite large. Universal shafts are used for connecting two axes where there is a large intersection or angular displacement. In cases where the two connecting shafts produce a large relative displacement additionally, flexible couplings are selected.
• The centrifugal force produced and the working universal coupling speed also play an important role in the selection of the right cardan shaft. For example in high speed transmission shafts, it is best to use couplings with high balance precision like diaphragm couplings instead of choosing eccentric slider coupling.
• The nature and size of the process torque that needs to be transmitted along with the buffering vibration function also play an important role in the choice of cardan shaft. For example, in heavy duty transmissions, gear couplings are selected for their high power. In processes where a severe impact load needs to be transmitted or the torsional vibration of the system needs to be eliminated, tire couplings are chosen. Couplings are often standardized by the companies themselves. A designer needs to just choose the right shaft for his or her system to attain maximum productivity.
• Do keep the nature of the torque also in consideration. This refers to the damping and buffering function requirements. For example, couplings with high elasticity like tire couplings are chosen where severe impact load needs to be transmitted or the torsional vibration has to be eliminated.
• The reliability of the cardan shaft working environment also plays an important role in the choice. The coupling performance is also decided by its need for lubrication. Those requiring regular lubrication get easily affected by the lubrication perfection, thus polluting the working environment of the shaft. Non metallic element made couplings like rubber couplings are highly sensitive to corrosive medium, temperature, strong light and aging.
• A Simple and low Maintenance, installation, manufacturing cost of the shaft along with a satisfactory performance is also a favourable point in choosing the right cardan shaft.  For example rigid couplings are often a popular choice because of its simple structure and installation convenience.

Thus, it is best to choose the right cardan shaft joint type according to the speed, load transfer and the installation accuracy of the parts.