Vibration and shock insulation — Definitions. Physical principles

The elastic suspension of machines to reduce the transmission of undesirable vibrations to their environment has become common practice, as has the flexible mounting of fragile or vibration-sensitive systems to better protect them. The implementation of these devices may seem straightforward enough, as long as the manufacturer's instructions are followed; yet there are many cases that require special attention to avoid unfortunate results, including premature wear or breakage.

To summarize the factors leading to this renewed attention when choosing anti-vibration or anti-shock insulation, we would mention in particular :

• the desire to lighten and reduce the size of machines while increasing their power, leading manufacturers to choose faster rotation speeds, less rigid casings and shafts, and less oversized frames;

• the desire to offer standardized ranges of engines, gearboxes and transmissions, couplings, generators, pumps, etc., which multiplies the number of possible combinations when assembling a group without the manufacturer having been able to validate all of them in terms of dynamics and vibration, resulting in configurations that are sometimes tricky to operate;

• a desire for modularity and flexibility in the layout of production workshops, which will lead users to locate control instruments or offices as close as possible to certain machines, thus further controlling and reducing the vibro-acoustic stresses they generate, or minimizing the interference of various previously separate production units;

• a concern for ergonomics and worker protection, which, after imposing the wearing of personal protective equipment that was often perceived as uncomfortable, now makes it necessary to specify ambient acoustic levels in workshops that are directly acceptable, without overly complex enclosure and cabin systems interfering with production flows or maintenance operations.

Well-conducted vibration isolation can solve all these problems, by carefully applying the concepts and methods detailed and illustrated in this article and in article , which deal successively with :

• Definitions and physical principles ;

• Technological and industrial solutions.