In this example, Delta Controls was approached by a customer in the nuclear industry who had a very specific problem.

This customer was trying to measure the differential pressure across a filter that was being used in a pipeline taking cooling water from a nearby lake. Due to the tight deadbands required, the customer had thought that a differential pressure switch with chemical seals would not be suitable and opted for a product with standard process connections instead.

Unfortunately, due to a particularly high mineral content in the lake water, these switches were becoming regularly blocked by deposits building up inside the process connection. As a result, the customer was having to regularly replace these switches with new ones. That was until they were introduced to Delta.

Delta’s engineers were able to solve this problem by designing a special pair of chemical seals that encorporated a flushing port to enable the area in contact with the lake water to be washed out, but that also minimized the effect they had on the switch’s deadband.