Machines and mechanical drive systems with unbalanceable inertia effects (due to
reciprocating parts), mounted on foundations which are relatively soft in the direction of vibration
measurements; machines with rotating slackcoupled masses such as beater shafts in grinding mills;
machines, like centrifugal machines, with varying unbalances capable of operating as selfcontained
units without connecting components; vibrating screens, dynamic fatigue-testing machines and
vibration exciters used in processing plants.