Mechanical Seals: Performance and Reliability

For mechanical seals, there is a common misconception that: (i) for similar applications, the useful life of the seals are very similar, and (ii) for a given application, the useful life is repeatable (for example, if the initial life is 2.5 years, the replacement frequency can be set at 2 years to prevent failure and consequent unplanned downtime in the future).

The downside to this maintenance philosophy is that mechanical seals – like all machine components – are subject to random failure modes, bringing uncertainty into estimates of useful life. Thus, the seal above may have had significantly more residual life left at the time it was removed. Or, it may fail before  the end of estimated life causing an unplanned shutdown.

The assumption that a wear component will have exactly the same usable life every time it is installed presents shortcomings. What if the industry had a method to indicate that the seal can run for four years before it breaks? What if there was a way to know exactly when the seal will fail?

In this presentation John Smiddy addresses these questions and offers the next step in maintenance strategies for mechanical seals.