DEFINITIONS AND TERMS (cont) - TM-750-245-40093

TM 750-245-4

FILM FAILURE: Failure of a lubricating film when the

d. Electrolytic Oxygen-Hydrogen Generation The

load is so extreme at the point of maximum pressure as

conductors by which current enters and leaves the

to squeeze the film down to the point of boundary

water, which is decomposed by the passage of the

lubrication.

current.

e. Resistance Welding The part or parts of a

FILTER GLASS: A colored glass used in goggles,

resistance welding machine through which the welding

helmets, and shields to exclude harmful light rays.

current and the pressure are applied directly to the work.

FIRE POINT: The temperature at which the vapors

ELECTRODE FORCE: a. Dynamic In spot, seam, and

continue to burn when mixed with air and ignited.

projection welding, the force (pounds) between the

electrodes during the actual welding cycle.

FLAME CUTTING: See oxygen cutting.

b. Theoretical In spot, seam, and projection

welding, the force, neglecting friction and inertia,

FLAME GOUGING: See oxygen gouging.

available at the electrodes of a resistance welding

machine by virtue of the initial force application and the

FLAME HARDENING: A method for hardening a steel

theoretical mechanical advantage of the system.

surface by heating followed by a rapid quench.

c. Static In spot, seam, and projection welding, the

force between the electrodes under welding conditions,

FLAME SOFTENING: A method for softening steel by

but with no current flowing and no movement in the

heating with a gas flame followed by slow cooling.

welding machine.

FLASH: Metal and oxide expelled from a joint made by

ELECTRODE HOLDER: A device used for mechanically

a resistance welding process.

holding the electrode and conducting current to it.

FLASH POINT: The temperature at which the vapors

ELECTRODE SKID: The sliding of an electrode among

will ignite momentarily when mixed with air and exposed

the surface of the work during spot, seam, or projection

to an open (open cup) or closed cup.

welding.

FLASH WELDING: A resistance welding process in

EMULSIFICATION: The tendency of an oil to mix with

which fusion is produced, simultaneously over the entire

water.

area of abutting surfaces, by the heat obtained from

resistance to the flow of current between two surfaces

ETCHING: A process of preparing metallic specimens

and by the application of pressure after heating is

and welds for macrographic or micrographic

substantially completed. Flashing is accompanied by

examination.

expulsion of metal from the joint.

FLASHBACK: The burning of gases within the torch or

FACE OF WELD: The exposed surface of a weld, made

beyond the torch in the hose, usually with a shrill,

by an arc or gas welding process, on the side from

hissing sound.

which welding was done.

FLAT POSITION: The position in which welding is

FACE SHIELD: A protective device to be worn on the

performed from the upper side of the joint and the face

head for shielding the face and neck.

of the weld is approximately horizontal.

FATIGUE WEAR: Wear due to excessive use, surface

FLOC POINT: The floc point is the point (temperature)

irregularities, and other defects. Often not due to

at which wax crystals precipitate from a mixture of the

lubricant failure.

oil to be tested and a refrigerant.

FAYING SURFACE: That surface of a member that is in

FLOW BRAZING: A process in which fusion is produced

contact with another member to which it is joined.

by heating with a molten nonferrous filler metal poured

over the joint until the brazing temperature is attained.

FILLER METAL: Metal to be added in making a weld.

See brazing.

FILLET WELD: A weld of approximately triangular cross

FLOW WELDING: A process in which fusion is

section, as used in a lap joint, tie joint or corner joint,

produced by heating with molten filler metal poured over

joining two surfaces at approximately right angles to

the surfaces to be welded until the welding temperature

each other.

is attained and the required

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