AUSJEEPOFFROAD.COM Jeep News Australia and New Zealand

AND MORE FOR THE LAYMAN
Welding Terms Glossary
.
Alternating Current (AC): An electrical current that reverses its direction at regular intervals, such as 60
cycles alternating current (AC), or 60 hertz (Hz).

Amperage: The measurement of the amount of electricity flowing past a given point in a conductor per
second. Current is another name for amperage.

Annealing: The opposite of hardening. A heat treating process used to soften a metal and relieve internal
stresses.

Arc: The physical gap between the end of the electrode and the base metal. The physical gap causes heat
due to resistance of current flow and arc rays.

Arc Length: Distance or air space between the tip of the electrode and the work
.
Arc Voltage: Measured across the welding arc between the electrode tip and the surface of the weld
pool.

Axis of Weld: Can be thought of as an imaginary line through the center of a weld, lengthwise.

Back Gouging: The removal of weld metal and base metal from the other side (root side) of a weld joint.
When this gouged area is welded, complete penetration of the weld
joint is assured
.
Bevel Angle: An angle formed between a plane, perpendicular to the surface of the base metal and the
prepared edge of the base metal. This angle refers to the metal that has been removed.

Butt Joint: A weldment where the material surfaces and joining edges are in or near the same plane.

Cold Lap: See preferred term Incomplete Fusion.

Conductor: An electrical path where current will flow with the least amount of resistance. Most metals are
good electrical conductors.

Corner Joint: Produced when the weld members meet at approximately 90o to each other in the shape
of an “L”.

Crater: A depression at the end of a weld bead.

Current: Another name for amperage. The amount of electricity flowing past a point in a conductor every
second.

Defect: One or more discontinuities that exceed the acceptance criteria as specified for a weld.

Depth of Fusion: The depth or distance that deposited weld metal extends into the base metal or the
previous pass
.
Direct Current: Flows in one direction and does not reverse its direction of flow as does alternating current.

Direct Current Electrode Negative (DCEN): The specific direction of current flow through a welding circuit
when the electrode lead is connected to the negative terminal and the work lead is connected to the positive
terminal of a DC welding machine.

Direct Current Electrode Positive (DCEP): The specific direction of current flow through a welding circuit
when the electrode lead is connected to a positive terminal and the work lead is connected to a negative
terminal to a DC welding machine.

Distortion: The warpage of a metal due to the internal residual stresses remaining after welding from metal
expansion (during heating), and contraction (during cooling).

Duty Cycle: The number of minutes out of a 10-minute time period an arc welding machine can be operated
at maximum rated output. An example would be 60% duty cycle at 300 amps. This would mean that
at 300 amps the welding machine can be used for 6 minutes and then must be allowed to cool with the fan
motor running for 4 minutes. (Some imported welding machines are based on a 5-minute cycle).

Edge Joint: A joint that occurs when the surfaces of the two pieces of metal to be joined are parallel or
nearly parallel, and the weld is made along their edges.

Electrode Extension: While welding, the length of electrode extending beyond the end of the gas cup.
Also referred to as electrical stickout.

Electron: A very small atomic particle which carries a negative electrical charge. Electrons can move from
one place to another in atomic structures. It is electrons that move when electrical current flows in an
electrical conductor.

Excessive Melt-Through: A weld defect occurring in a weld joint when weld metal no longer fuses the
base metals being joined. Rather, the weld metal falls through the weld joint or “burns through”. Also
referred to as excess penetration.

Face: The surface of the weld as seen from the side of the joint on which the weld was made.

Face Rotation: Can be thought of as an imaginary line from the axis of the weld through the center of the
welds face. This face rotation angle along with the axis angle determine the actual welding position. Face
rotation is measured in a clockwise direction starting from the 6 o’clock position. A weld with the face rotation
at 12 o’clock would have the face rotation at 180o.

Ferrous: Refers to a metal that contains primarily iron, such as steel, stainless steel and cast iron.

Filler Metal: The metal added when making a welded, brazed, or soldered joint.

Fillet Weld: A weld that is used to join base metal surfaces that are approximately 90o to each other, as
used on T-joint, corner joint or lap joint. The cross sectional shape of a fillet weld is approximately triangular.

Fit-Up: Often used to refer to the manner in which two members are brought together to be welded, such
as the actual space or any clearance or alignment between two members to be welded. Proper fit-up is
important if a good weld is to be made. Tacking, clamping or fixturing is often done to ensure proper fit-up.
Where it applies, base metal must be beveled correctly and consistently. Also, any root openings or joint
angles must be consistent for the entire length of a joint. An example of poor fit-up can be too large of a
root opening in a V-groove butt weld.

Flat Position: When welding is done from the top side of a joint, it is in the flat position if the face of the
weld is approximately horizontal. Sometimes referred to as downhand welding. The axis angle can be from
0o–15o in either direction from a horizontal surface. Face rotation can be from 150o – 210o.

Freeze Lines: The lines formed across a weld bead.They are the result of the weld pool freezing. In appearance
they sometimes look as if one tiny weld was continuously laid upon another.

Groove Angle: When a groove is made between two materials to be joined together, the groove angle
represents the total size of the angle between the two beveled edges and denotes the amount of material
that is to be removed.

Ground Connection: A safety connection from a welding machine frame to the earth. Often used for
grounding an engine driven welding machine where a cable is connected from a ground stud on the welding
machine to a metal stake placed in the ground. See Work Connection for the difference between work
connection and ground connection.

Ground Lead: When referring to the connection from the welding machine to the work, see preferred
term Work Lead.

Heat Affected Zone (HAZ): The portion of a weldment that has not melted, but has changed due to the
heat of welding. The HAZ is between the weld deposit and the unaffected base metal. The physical makeup
or mechanical properties of this zone are different after welding.

Heat Sink: A good weld needs a certain amount of base metal to absorb the high heat input from the
welding arc area. The more base metal, or the thicker the base metal, the better heat sink effect. If this
heat sink is not present, too much heat will stay in the weld area, and defects can occur.

Horizontal Position: Occurs when the axis of the weld is from 0o–15o from the horizontal, and the face
rotation is from either 80o –150o or 210o – 280o for groove welds, or from either 125o –150o or 210o–
235o for fillet welds.

Included Groove Angle: See preferred term Groove Angle.

Incomplete Fusion: Molten filler metal rolling over a weld edge but failing to fuse to the base metal. Also
referred to as cold lap.

Inverter: Power source which increases the frequency of the incoming primary power, thus providing for a
smaller size machine and improved electrical characteristics for welding, such as faster response time and
more control for waveshaping and pulse welding.

Joint Design: A cross-sectional design and the given measurements for a particular weld. Generally
includes included angles, root opening, root face, etc.

Joint Root: That part of a joint that comes closes together where the weld is to be made. This maybe an
area of the joint or just a line or point of that joint.

Lap Joint: A joint that is produced when two or more members of a weldment overlap one another.

Load Voltage: Measured at the output terminals of a welding machine while a welder is welding. It
includes the arc voltage (measured while welding), and the voltage drop through connections and weld
cables.

Open Circuit Voltage (OCV): As the name implies, no current is flowing in the circuit because the circuit
is open. The voltage is impressed upon the circuit, however, so that when the circuit is completed, the current
will flow immediately. For example, a welding machine that is turned on but not being used for welding
at the moment will have an open circuit voltage applied to the cables attached to the output terminals
of the welding machine
.
Output Control: An electrical switch that is used to energize or de-energize output terminals of a welding
machine. In some types of welding machines they can be of solid state design, with no moving parts and
thus no arcing of contact points.

Overhead Position: When the axis angle is from 0o – 80o and the face rotation is from 0o – 80o or 280o–
360o for groove welds or from 0o – 125o or 235o – 360o for fillet welds, the weld position is considered to
be in the overhead position.

Parameters: The welding settings on a welding machine such as voltage and amperage, normally read
on a volt meter and an amp meter. It may also include things as travel speed, electrode size, torch angle,
electrode extension and weld joint position and preparation.