DEFINITIONS AND TERMS

TM 750-245-4

B-3. DEFINITIONS AND TERMS

ARC WELDING: A group of welding processes in which

a fusion is produced by heating with an electric arc of

arcs, with or without the use of filler metal.

ABRASIVES: Emery cloth or aluminum oxide cloth grit

size 300 to 400 shall be used for cleaning cold, surface

AS WELDED: The condition of weld metal, welded

treated soldering iron tips and resistance heating

joints, and weldments after welding and prior to any

electrode tips. The use of abrasives for cleaning plated

subsequent thermal or mechanical treatment.

soldering iron tips should be limited to only experienced

maintenance personnel. This type of cleaning is rarely

ATOMIC HYDROGEN WELDING: An arc welding

required where soldering iron holders are utilized.

process in which a fusion is produced by heating with an

electric arc maintained between two metal electrodes in

ABRASIVE WEAR: Wear due to hard particles such as

an atmosphere of hydrogen. Pressure and / or filler

sand, metal, etc., between the surfaces.

metal may or may not be used.

ACETONE: A flammable, volatile liquid used in

AXIS OF A WELD: A line through the length of a weld,

acetylene cylinders to dissolve and stabilize acetylene

perpendicular to a cross section at its center of gravity.

under high pressure.

ACETYLENE: A highly combustible gas composed of

carbon and hydrogen. Used as a fuel gas in the oxy-

BACK PASS: A pass made to deposit a back weld.

acetylene welding process.

BACK STEP: A sequence in which weld bead

ACTUAL THROAT: See throat of fillet weld.

increments are deposited in a direction opposite to the

direction of progress.

ADHESIVE WEAR (GALLING WEAR): High surface

temperature or oil film rupture wear.

BACK WELD: A weld deposited at the back of a single

groove weld.

AIR ACETYLENE: A low temperature flame produced

by burning acetylene with air instead of oxygen.

BACK FIRE: The momentary burning back of a flame

into the tip, followed by a snap or pop, then immediate

ALLOY: A mixture with metallic properties composed of

reappearance or burning out of the flame.

two or more elements of which at least one is a metal.

BACKHAND WELDING: A welding technique in which

ALLOY: A mixture with metallic properties composed of

the flame is directed towards the completed weld.

two or more elements of which at least one is a metal.

BACKING STRIP: A piece of material used to retain

ANILINE POINT: The critical solution temperature of a

molten metal at the root of the weld and / or increase

50-50 mixture of the oil in question with aniline.

the thermal capacity of the joint so as to , prevent

excessive warping of the base metal.

ANTI-WICKING TOOL: Special shaped holding type

tweezers, designed to stop capillary flow of liquid solder

BACKING WELD: Backing in the form of a weld.

to prevent wicking of stranded conductors. These are

manufactured to fit the different wire sizes. These may

BACK UP: In flash and upset welding, a locator used to

be used as thermal shunts during the soldering

transmit all or a portion of the upsetting force to the work

operation.

pieces.

ARC BLOW: The swerving of an electric arc from its

BARE ELECTRODE: An arc welding electrode that has

normal path because of magnetic forces.

no coating other than that incidental to the drawing of

the wire.

ARC BRAZING: An electric brazing process wherein the

heat is obtained from an electric arc formed between the

BARE METAL-ARC WELDING: An arc welding process

base metal and an electrode, or between two electrodes.

in which fusion is produced by placing an unshielded arc

between a bare or lightly coated electrode and the work.

ARC CUTTING: A group of cutting processes in which

Pressure is not used and filler metal is obtained from the

the severing of metals is accomplished by melting with

electrode.

the heat of an arc between an electrode and the base

metal. See carbon-arc cutting, metal-arc cutting and

BASE METAL: The metal to be welded or cut. In alloys

oxy-arc cutting, and air-arc cutting.

it is the metal present in the largest proportion.

B-4