Design Skills

A Vast Experience in Application and Design


AAM's Halifax Manufacturing Facility (formerly Metaldyne, and Holset Engineering) has more than 60 years' experience in the application and design of viscous torsional vibration dampers on high, medium and low speed diesel engines.

Viscous dampers are fitted to the front (free) end of most diesel engines to control torsional vibrations. The viscous damper is fitted to control the torsional vibrations developing in the crankshaft induced by the combustion process in the engine. By reducing oscillations in the crankshaft to a low amplitude, the viscous damper keeps the material stresses within permitted design limits and prevents premature failure of the crankshaft due to metal fatigue.

Other product applications for AAM Halifax Manufacturing Facility viscous dampers include:

  • Diesel engine camshaft dampers to limit the stresses on the camshaft due self-excited torsional vibration.
  • Vehicle (truck, tram and bus) transmission dampers to prevent noise vibration and harshness which contribute to passenger discomfort.
  • Machine tool transmission dampers to prevent gear chatter.
  • Dampers on other machinery (e.g. pumps, centrifuges) to control torsional vibration.



The following steps are typically carried out by AAM Halifax Manufacturing Facility to supply a viscous damper matched to the application:


Assess data requirement to fully define the torsional properties of the system.


Detailed modelling of the torsional vibration of the system, conducted using the latest in-house and proprietary computer programs.


Design of bespoke viscous damper to suit the TV characteristics of the application considering:

combustion characteristics (including misfire)
permitted stress, torque and acceleration limits
space available for damper
installation inside or outside engine
with or without oil cooling
Liaison with engine designers and Classification Societies as required.

Detailed TV analysis for marine propulsion and power generation applications is a specific requirement from the Classification Societies.

Customers are invited to contact to discuss specific torsional vibration applications.