F


Fat

An animal or vegetable oil which will combine

with an alkali to saponify and form a soap.

FFV

Flexible-Fuel Vehicle

Fiber Grease

A grease with a distinctly fibrous structure, which

is noticeable when portions of the grease are

pulled apart.

Filler (lubricants)

Any substance, such as talc, mica or various

powders, which may be added to a grease to

make it heavier in weight or consistency, but

which serves no useful function in making the

grease a better lubricant. (Editor’s note: Such

filler may also be added to certain lubricating

oils or other lubricants).

Film Strength

The property of an oil which enables it to

maintain an unbroken film on lubricated

surfaces under operating conditions, where

otherwise there would be scuffing or scoring of

the surfaces.

Fire Point

The lowest temperature at which, under

specified conditions in standardized apparatus,

a petroleum product vaporizes sufficiently

rapidly to form above its surface an air-vapor

mixture which burns continuously when ignited

by a small flame.

Fire Point Test (COC)

(see Cleveland open-cup tester)

Flash Point

The lowest temperature at which vapors arising

from the oil will ignite momentarily (i.e., flash)

when exposed to a flame.

Flash Point Test (COC)

(see Cleveland open-cup tester)

Flash Point Test

(Pensky-Martens closed tester)

A method of test for the determination of the

flash point of liquid fuels flashing below 175°F,

with the exception of fuel oils.

Flash Point (Tag closed-cup tester)

A method of test for the determination of the

flash point of liquid fuels flashing below 175°F,

with the exception of fuel oils.

Floc Point

The temperature at which wax or solids

separate in an oil.

Foam

An agglomeration of gas bubbles separated

from each other by a thin liquid film which is

observed as a persistent phenomenon on the

surface of a liquid.

Four-Ball Tester

This name is frequently used to describe either

of two similar laboratory machines, the Four-

Ball Wear Tester and the Four-Ball EP Tester.

These machines are used to evaluate a

lubricant’s anti-wear qualities, frictional

characteristics or load carrying capabilities. It

derives its name from the four ½ inch steel balls

used as test specimens. Three of the balls are

held together in a cup filled with lubricant while

the fourth ball is rotated against them.

Fretting Corrosion

A special case of fretting in which one or more

of the surfaces, or the wear particles therefrom,

react with their environment. Mechanical wear

initiates fretting, then chemical action or

“corrosion” results from the exposure of virgin

metal surface to the air.

Front-end Volatility

A term applied to the volatility of the lower boiling

fractions of gasoline.

Fuel Sensitivity

The response of a motor fuel to the change in

engine severity between the operating

conditions of the ASTM Research Method (D

908) and ASTM Motor Method (D 357);

numerically equal to the difference between the

Research and Motor octane numbers.

FZG Test

A German gear test for evaluating EP

properties.