Diamond Coating for Seals 

Since the corrosion inhibitor hydrazine has been forbidden as of the health risks connected to it, mechanical seals of boiler feed water pumps show signs of electrical corrosion unknown before. The relative movement between the sliding ring and the stationary ring provokes static charging which – in contrast to the past – are no longer diverted as of the very low conductivity of the boiler water below one micro-Siemens per cm [μS/cm].

Within short periods of operation – in some cases only a few hundred operational hours – pieces having the size of finger tips break off from the sliding and/or the stationary ring and cause rapid increases in leakage current. Diamond-coated mechanical seals can help to avoid this problem.

You can find all details about the seals including photos here.