Study looks at enclosure seal performance

Edited by the Electronicstalk editorial team Feb 21, 2003

BHR Group has recently completed a project to identify and control the mechanisms influencing the performance of seals for high integrity electronic equipment in arduous operating environments.

The sealing technology team at BHR Group has recently completed a project to identify and control the mechanisms influencing the performance of seals for high integrity electronic equipment in arduous operating environments.

Many electronic components such as signal transmission and receiving antennas, microwave boosters and military electronics require to operate in a moisture-free environment.

Conversely they often produce significant amounts of heat and sometimes trace amounts of elements that can affect the performance of delicate electronic components and which require removal.

Operating temperatures in exposed locations can vary rapidly especially during tropical storms.

The sealing system not only needs to accommodate these thermal variations especially the difference in the expansion coefficients of the component materials, but also take account of permeation through the elastomer and the effects of ageing.

The requirement to use electrically conductive material and account for vibration and shock loading increase design parameters also needs to be accommodated.

BHR Group has developed life prediction software using finite element simulation methods, coupled to permeation and ageing models and novel experimental methodologies.

These can be applied to allow engineers to assess design variables, from basic geometry to the affect of tolerances, and hence select the optimum sealing arrangement with respect to both duty and cost requirements.

The parameters used in the design are then translated to the manufacturing and procurement process as a functional specification to aid quality control of the production.