Unit 4 Balancingofrotatingmasses 131127012048 Phpapp01
Unit 4 Balancingofrotatingmasses 131127012048 Phpapp01
Unit 4 Balancingofrotatingmasses 131127012048 Phpapp01
Balancing of Rotating
Masses
Hareesha N Gowda
Asst. Professor
Dept of Aeronautical Engg
Dayananda Sagar College of Engineering
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What is Balancing ?
Often an unbalance of forces is produced in
rotary or reciprocating machinery due to the
inertia forces associated with the moving
masses.
Balancing is the process of designing or
modifying machinery so that the unbalance
is reduced to an acceptable level and if
possible is eliminated entirely.
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1. Analytical method
First of all, find out the centrifugal force exerted by each mass on the
rotating shaft.
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2. Graphical method
The magnitude and position of the balancing mass may
also be obtained graphically as discussed below :
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2. Graphical method
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Take: 10kg-m=1cm
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For the static balance of the pulleys, the centre of gravity of the system must
lie on the axis of rotation. Therefore a force polygon must be a closed figure.
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