Gas Turbine Handbook : Principles and Practices

Accessories 101
Fire Point
The lowest temperature at which the vapor will continue to burn
when a flame is applied.
Flash Point
The temperature at which the vapor from an oil will flash when
a flame is applied under standard conditions. The flash point minimums
are set to meet safety limits for products lighter than lube oil.
Flash point is useful in detecting contamination of the lube oil by fuel
oils. Typical values for flash point are listed in Table 6-1:
Table 6-1.
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Product
Flash Point
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Gasoline
>32°F (0°C)
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Diesel Fuel
150°F (65°C) to 200°F (93°C)
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Lube Oil
300°F (149°C) to 650°F (343°C)
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Pour Point
The lowest temperature at which an oil will flow when cooled
under standard conditions.
Cloud Point
The temperature at which a cloud of wax crystals appear when
oil is cooled under certain standard conditions.
Flock Point
The temperature at which wax separates as a flock when a mixture
of 10% oil and 90% refrigerant is cooled under certain conditions.
These temperatures define the flow properties of oil under low
temperature conditions (pour and cloud points are for non-miscible
refrigerants and flock point is for miscible refrigerants). This property
is significant to refrigeration and air conditioning plant compressor
operators. Pour points of –30°F (–34°C) to –40°F (–40°C) or flock
points of –60°F (51°C) to –70°F (–57°C) are necessary.