File Name: static and dynamic balancing .zip
The balancing of rotating bodies is important to avoid vibration. To help with balancing, it involves simply moving the centre of gravity to the centre of rotation. For systems to be completely balanced both the force and couple polygons should be closed.
Report Download. ForewordMany people are needlessly appre hensive of performing their own dy namic balancing procedure. InstallationFirst attach t w o accelerometers, one near each of the bearings of the rotor being balanced, to mea sure vibration. Mount a photoelectric trigger to give one pulse for each revolution of the rotor. Connect the accelerometers via a changeover switch, to a vibration meter and hence to the " u n k n o w n " channel of a phase meter.
Unbalance is the most common source of vibration in machines with rotating parts. It is a very important factor to be considered in modern machine design, especially where high speed and reliability are significant considerations. Balancing of rotors prevents excessive loading of bearings and avoids fatigue failure, thus increasing the useful life of machinery. Unbalance in a rotor is the result of an uneven distribution of mass, which causes the rotor to vibrate. The vibration is produced by the interaction of an unbalanced mass component with the radial acceleration due to rotation, which together generate a centrifugal force. Since the mass component rotates, the force also rotates and tries to move the rotor along the line of action of the force.
This work is an attempt to evolve a means for statically and dynamical balancing of mechanical components. This will no doubt evolve greater success in ensuring sound fabrication of our local machine and ensuring that life span of such machine is prolonged since vibration will be reduced to the bearest minimum. Every wheel and its shaft have to be in a state of balanced, two mating shaft in rotation have to be in a state of static and dynamic balance. This is because unbalance condition produce centrifugal force which increase as the speed of the machine increase, causing damage to machine parts. To achieve the aim of static and dynamic balancing, various design alternatives for achieving the design solution were synthesized and a choice of economic method which will satisfy the objective was made.
Bench top apparatus for experiments in balancing a rotating mass system, statically and dynamically. This product allows students to do experiments in balancing a rotating mass system and check their results against accepted theory. A sturdy base unit holds a test assembly on four flexible mounts.
Figure If the rotor is statically balanced, it will not roll under the action of gravity, regardless of the angular position of the rotor. The requirement for static balance is that the center of gravity of the system of masses be at the axis of rotation.
Many people are needlessly apprehensive of performing their own dynamic balancing procedure. This application note will demonstrate with the aid of several worked examples, how easy it is to balance rotating machinery. As the object would now be completely balanced in the static condition but not necessarily in dynamic this is known as Static Balancing. Secondary Balancing describes the process where primary forces and secondary force couples caused by unbalanced mass components in a rotating object may be resolved into two or more planes and balanced by adding mass increments in those planes. This balancing process is often known as Dynamic Balancing because the unbalance only becomes apparent when the object is rotating. After being balanced dynamically, the object would be completely balanced in both static and dynamic conditions. The difference between static balance and dynamic balance is illustrated in Fig.
The rotating system is essentially a shaft, mounted on bearings, supported in a rigid frame, and driven by a small variable speed motor attached to the frame. Four discs, to which masses may be attached, are rigidly secured to the shaft. Each disc is suitably drilled and the sets of holes are positioned so that various conditions of un-balance in a rotating system can be simulated and the normal methods used to determine the magnitude and position of the counter-balance masses.