Fill in the correct form of the word in capital letters
Vibration may be in any LINE direction and it may be ROTATE . Vibration may be RESONATE or forced. It can occur at any frequency up to those which are COMMON called noise. It can be controlled, once recognised, by minimizing at source, by DAMP and by arranging to avoid exciting resonance.
The reciprocating motion of the piston in an engine cylinder creates out- of - balance forces acting along the cylinder, while the CENTRIFUGE force associated with the crankpin rotation creates a rotating out- of- balance force. If not in themselves necessarily damaging, these forces create OBJECT vibration and noise in the engine foundations, and through them to the ship in which the engine is operating. Balancing is a way of controlling vibrations by arranging that the overall summation of the out-of-balance forces cancels out, or is reduced to a more ACCEPT amount.
Elastomer based mounting systems are used to suppress or attenuate noise and vibration in ships. Ruber to metal bonded systems are the most commonly applied anti vibration mountings. Such mountings mainly benefit PROPEL engines, gensets and diverse auxiliary machinery such as ventilation fans, compressors, pumps, sewage treatment units, refrigeration plants and instrument panels. There are also active mountings which can enhance noise INSULATE many times over by exploiting anti vibration to counteract vibration from the engine.
