Tuned Mass Dampers

A Tuned Mass Damper (TMD) is a device designed to add damping to a structure for a specific frequency. The extra damping will reduce the movement of the structure to an acceptable level.

A tuned mass damper contains a mass that is able to oscillate in horizontal or vertical direction. The oscillation frequency of the mass can be tuned using springs, suspension bars or ball transfers. When the structure starts to oscillate the mass of the TMD  will oscillate in opposite direction, a frictional or hydraulic component connected between the structure and mass turns the kinetic energy into thermal energy.

The design of an TMD depends on the oscillation frequency and mass of the structure, direction of the movements (horizontal or vertical) and available space.

TMD systems

The Roll-Box damper is a cylindrical box with a diameter of about 0.60 m and a height of 0.50 m. Inside is a moving weight of 10 to 40 kg. The box is fixed to the vibrating structure. The effect will be an increase of the damping up to 10% of the critical damping. Generally this is sufficient to prevent serious vibrations.

The Roll-Ring damper (horizontal) is a ring shaped damper around a chimney with a weight of 10 to 40 kg. The ring moves over minimal three bearings. The effect of this ring is an increased damping of the vibration to about 10% of the critical
                           damping. This prevents cross-wind vibrations.

The Box-Damper (horizontal) has a moving weight of 40 to 30,000 kg hanging on suspension bars. The weight moves independently from the structure.
The damper mass inclusive the suspension bars and the hydraulic shock absorbers are installed in a closed box, protected aggenst rain (and acid if applicable).

The  Hydamp System (horizontal) has a moving mass hanging on suspension bars with a length between 0.20 and 2.500 m depending on the frequency of the structure that has to be damped. The damper mass moves independently from the structure. Between the structure  and the damper mass  hydraulic shock
                           absorbers are installed to absorb the energy. Consequently vibrations will be
                           reduced.

 The Spring damper system (horizontal & vertical) has a moving mass mounted on helical springs. The mass and hydraulic shock absorber(s) are connected by a prolink suspension system. This system enables us to calibrate the damping value with high precision.

Guarantee
All above mentiond Tunes Mass Damper solutions have proven themselves in practice.
The solutions we offer ensure the reducing of the vibration to an acceptable level and prevent fatigue damage.