Evaporation in the lubrication gap

Data reflect evaporation

Evaporation in the sealing gap damages the seal! But how do you recognize when this evaporation occurs in the mechanical seal?

Our application engineer Philipp Arneth explains this on our test bench:

“By monitoring the mechanical seal with our ultrasonic technology, it is easy to see what condition the seal is currently in during operation.

For example, if evaporation of pumping or sealing media occurs in the sealing gap, this is reflected in the transmitted data,” explains Philipp.

The illustration shows that the lubricant – in this case water – changes from a liquid to a gaseous state. This results in insufficient lubrication and solid contact in the gap. This operating state alone already damages the seal, but it is also an effect that can be followed by many different damage processes. These effects can occur in processes in which gases are dissolved in liquids (e.g. carbonic acid in drinks) or in processes with high temperatures or a pressure difference upstream and downstream of the seal (e.g. highly volatile substances in chemical processes).

Results from the test bench

Pumpenversuchsstand der BestSens AG

On our test bench, the media temperature was influenced by varying the speed in order to demonstrate this effect. When checking the results, Philipp is very satisfied: “Here you can clearly see the evaporation in the seal and the seal condition outside the defined standard range.”