THE IMPACT OF HYDRAULIC SYSTEMS ON THE HUMAN BEING AND THE ENVIRONMENT

Some hazards posed by the operation of hydraulic systems, connected with low-frequency vibrations
and noise are presented. Special attention is focused on infrasounds. The sources of
low-frequency vibrations and noise and the ways of reducing them are indicated. Moreover,
this paper deals with the effects of external mechanical vibrations on hydraulic valves. An
original solution ensuring the effective reduction of vibrations and noise in a wide frequency
range, i.e. a wide-band damper of pressure fluctuations, also performing the function of an
acoustic filter, is proposed. The results of preliminary experimental tests of simple vibration
insulators are reported. The effectiveness of the damper has been confirmed by the results
of laboratory tests and tests carried out on engineering machines working in real conditions.
Problems relating to the noise emitted into the environment by machines equipped
with hydraulic systems are covered by Polish and EU standards and directives, e.g. PN-ISO
9612:2004, Directive No. 2000/14/EC and Directive No. 98/37/WE.