Module 2   :  Dynamics of Rotating Bodies; Unbalance Effects and Balancing of Inertia  Forces;  Field  Balancing                          and Balancing Machines. 
Lecture 1 :   Concept of unbalance; effect of unbalance
 

Thus we have:

 

(2.1.2)
 

where is the natural frequency of the system given by

 

   

 (2.1.3)
 

Typical variation of the deflection of the shaft is given in Fig. 2.1.3 below. It is deserved that for very low speeds of operation, (i.e ) . The unbalanced forces do not cause significant deflection in the shaft. Towards the high speed end(i.e ), . Thus S and G interchange their relative locations and G tends to coincide with the line of bearings.

In between, when , shaft deflection r becomes excessively large

 


Fig 2.1.3a Variation of the Deflection of the Shaft

 


Fig 2.1.3b


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