Torsional Vibration Dampers
Many engines are equipped with one or two Hasse & Wrede viscous shear type torsional vibration damper attached to the forward or non-flywheel end of the crankshaft. The purpose of this vibration damper is to minimise the influence of the torsional vibrations developing in the crankshaft, so that the material stresses arising from these conditions are kept within permissible limits.
A damper which is in poor condition or which is not operating will increase the torsional vibration, resulting in an increase in material stresses and can lead to undue strain on the crankshaft and transmission components.
The lifetime of a damper, among others, depends on its thermal load and on the running conditions. From experience we know however that the effective operation of the damper may reduce after some period.
When a damper requires overhaul, it must be completely dismantled to enable removal of contaminated fluid, possible machining of any internal mechanical damage and modification to current specification. All dampers are leak/volume check by vacuum filling rigs to ensure correct service volume is achieved. Therefore, dampers cannot be overhauled in-situ and must be removed and returned to our factory.