Maintenance of the seal depends on checking the seal for leakage as well as maintenance of the drive/gearbox. For dry seals the consumption of nitrogen should be checked with a rotameter, which measures in cubic feet per hour, at least once a day. When the consumption of nitrogen increases that is a warning the seal could be failing. For lubricated seals, monitor the consumption of barrier fluid in the lubricator. When the consumption of barrier fluid increases, that is an indication of seal failure.
The agitator runout should be measured at least once per year or after an increase in nitrogen or barrier fluid is noticed. The runout must be measured before the drive is disassembled after a seal failure and during reassembly of the drive during the installation of a new seal. The bearing float of the drive gearbox should be checked at least once per year and especially after a seal failure. If the drive loses the pre-load in the output bearings then it will cause higher than normal runout which will lead to seal failure.