Torsional Vibration Damper: What is it for?

Torsional Vibration Damper
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The torsional vibration damper is used to dampen crankshaft vibrations that occur during the combustion process.

These dampers are located at the end of the crankshaft and the pulley.

Torsional Vibration Damper Function

During combustion, various forces act on the crankshaft, causing the shaft to undergo torsional (circular) oscillations. In contrast, the oscillations' method and intensity depend on the crankshaft's construction. A torsional vibration damper is used to eliminate this vibration.

Torsional shock absorbers are connected by a rubber ring to the drive disk, while the disk is fixed on the crankshaft. If the crankshaft starts to oscillate, this oscillation is damped by a damping mass, i.e., a damping rubber. In addition to rubber, silicone oil, which is highly viscous, can also be used.

If the shock absorber were not in place, the vibration could equalize with the vibration of the crankshaft, resulting in resonance, which could break the crankshaft, the replacement of which would cost you hundreds to thousands of euros.

Video showing the function of the torsional vibration damper