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Turbine Auxiliaries 135

Figure 7.11 Typical schematic of a vacuum dehydrator system used for purifying steam
turbine lubricants. (Allen Filters Inc., Springfield, Mo.)

7.5 Gland Seal Systems
Gland seal systems are piping arrangements that take steam from
high-pressure labyrinth or carbon seal ports to locations operating at
lesser pressure. It can be noted from Fig. 7.9 that leakoff steam exiting
from a higher pressure labyrinth port becomes injected steam at a
lower pressure labyrinth port. Gland condensers are also part of the
sealing system for large steam turbines. (See also Fig. 2.27.)

7.6 Lube Oil Purifiers
Lube oil reclaimers or purifiers are needed if long-term reliable opera-
tion of steam turbines is desired. While it is generally well known that
particulate or dirt contamination can be addressed by proper filtration,
water contamination concerns are sometimes overlooked.
Water contamination causes the physical and chemical properties of
oil to deteriorate. Viscosity, oxidation stability, lubricity, additives, and
other oil properties could be affected. The oil must be replaced or recon-
ditioned to avoid causing performance degradation and damage to