I HAVE A QUESTION ON WEAR DEBRIS LIMITS IN ADDITION TO WATER CONTENT LIMITS IN STEAM TURBINE OF 25 MW- MAKE SIEMENS

WEAR LIMITS & WATER CONTENT LIMITS WILL HELP TO MONITOR THE TURBINE OIL FOR PERFORMANCE AND TAKE PREVENTIVE ACTION.

Kuppu: WATER - It is generally accept that water above the saturation point is too much. R&O oils will hold about 250 ppm in solution at 140F. At 70F that drops to a 100 ppm or so, (not precise but close). ASTM and others say 0.20 (2000 ppm) is a warning. This is way too high for a well running steam turbine. My advice is to monitor the water level by ASTM D6304 Water by Karl Fischer Method to establish a baseline. This should be below 100 ppm. Once the water increase by 50% begin to investigate where it's coming from.

WEAR - Good luck! There are seldom cases where wear rates have been established as viable predictive tools in steam turbines. More to the point I would use particle counting as the acceptance criteria. Check with the OEM about targets. Once you have seen an increase use SEM-EDS to determine the morphology, precise size, concentration and elemental make up. An additional test for the routine suite of tests might be metals after acid digestion. This helps measure all metals in all size ranges.

Best Bill H

Get yourself a copy of ASTM D4378. This document spells out how to monitor Gas and Steam Turbine oils. It is much more than water and wear debris. Good Luck! Please spend the money and buy this document...it will give you the info you need. If you use Mobil lubricants...your Mobil rep can show you a copy of this...