Oil Analysis |
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We provide five accurate tests for chillers.
Water (by the Karl Fischer method)
This is a highly accurate, precise, and objective method for determining
total water contamination present in a fluid, whether the water is
suspended, dissolved, or emulsified. A co-distillation used with this
test method eliminates interference affected by the presence of sulfur
containing additives such as anti-wear agents and rust-inhibitors.
Water rusts iron and steel surfaces, accelerates corrosion, depletes and
degrades additives, promotes base oil oxidation, and reduces lubricant
effectiveness. Large amounts of water can form sludge and free water
may cause the formation of hard brittle deposits on bearing surfaces and
promote bacteria growth. All of these factors can impair machine
reliability.
Spectrochemical Analysis
This test determines the concentration of elements represented in the
entrained fluid sample by emission spectroscopy.
These
metals indicate wear on particular components of an individual unit.
The particles of these metals will indicate a wear problem on the
microscopic level before the problem can be detected by conventional
means. The existence of a wear problem is determined not only by
absolute values of metals, but more importantly by a relative increase
or trend in one or more metals.
Viscosity
Viscosity
is the measurement of internal friction, or a fluid’s resistance to
flow, under gravitational forces. Viscosity affects equipment
operation, friction losses, and oil film thickness on bearings. Its
measurement and trending is critical to used oil analysis. Even modest
changes in viscosity may adversely influence the lubricant’s performance
and stability, possibly causing metal-to-metal contact and wear. Change
in a lubricant’s viscosity is a common symptom of a host of other
problems, such as excessive contamination (from water, glycol, fuel,
solvents, and/or very small particles), chemical degradation, severe
mechanical shearing of the oil, or mixing with incompatible fluids.
Other units of measurement, such as SAE grade, are related to a fluid’s
viscosity. Since viscosity varies inversely with temperature, its value
is meaningless until the temperature at which it is reported.
Acid Number
Formerly
known as Total Acid Number, this is a measure of acidic constituents
present in a fluid. As oil ages and oxidizes, small amounts of acidic
by-products are formed in the oil causing the acid number to increase.
A high acid number typically indicates that the oil’s useful life has
expired and needs to be changed. Water contamination in highly acidic
fluids strengthens the corrosive potential of acids, resulting in a
highly corrosive fluid capable of aggressively attacking bearing
materials and other surfaces.
Total Solids
Particles of carbon or agglomerates of carbon and other material can indicate deposition or dispersant additive or particulate drop-out in a component. A rapid increase in these particles indicates a serious situation which must be addressed through appropriate unit maintenance or fluid replacement.
