Welding

Constant-Speed Wire Feeder

Feeder operates from 24 or 115 VAC supplied by the welding power source.

Pulsed-spray transfer

For this variation of spray transfer, the welding machine "pulses" the output between high peak currents and low background currents. The weld pool gets to cool slightly during the background cycle, allowing for welding in all positions on either thin or thick metals.

Arc Control (Dig)

Gives a power source variable additional amperage during low voltage (short arc length) conditions while welding. Helps avoid "sticking" stick electrodes when a short arc length is used.

Power Factor Correction

Normally used on single-phase, constant current power sources to reduce the amount of primary amperage while welding.

Hybrid laser-arc welding

A combination of laser and arc welding which produces deep penetration welds with good tolerance to poor joint fit-up.

Countersink

A conical hole cut into a manufactured object, or the cutter used to cut such a hole.

Convex Contour

A contour in which the face of the weld curves out.

Flat contour

A contour in which the face of the weld is flat.

Flush contour

A contour that requires that the weld be laid or finished in such a way that it rests flush against the part or base material itself.

Air Carbon Arc Cutting (CAC-A)

A cutting process by which metals are melted by the heat of an arc using a carbon electrode. Molten metal is forced away from the cut by a blast of forced air.

Light Amplification by Stimulated Emission of Radiation (Laser)

A device that provides a concentrated coherent light beam.

Plasma

A gas that has been heated to at least partially ionized condition, enabling it to conduct an electric current.

Arc Cutting

A group of thermal cutting processes that severs or removes metal by melting with the heat of an arc between an electrode and the work piece.

Arc Welding

A group of welding processes which produces coalescence of metals by heating them with an arc, with or without the application of pressure and with or without the use of filler metal.

Butt Joint

A joint between two members lying in the same plane

Lap joint

A joint between two overlapping members in parallel planes.

Miter joint

A joint made by beveling each of two parts to be joined, usually at a 45° angle, to form a corner, usually a 90° angle

Backing

A material (base metal, weld metal, or granular material) placed at the root of a weld joint for the purpose of supporting molten weld metal.

KW (Kilowatts)

A measure of power, calculated as volts times amps divided by 1,000.

Chipping

A method of removing surface defects with a chisel, so that the defects will not be worked into the finished product.

Pulsed TIG (TIG-P)

A modified TIG process appropriate for welding thinner materials.

Pulsed MIG (MIG-P)

A modified spray transfer process that produces no spatter, because the wire does not touch the weld puddle.

Resistance Spot Welding (RSW)

A process in which two pieces of metal are joined by passing current between electrodes positioned on opposite sides of the pieces to be welded. There is no arc with this process.

Laser beam welding

A process that fuses material with the heat from a concentrated coherent beam impinging upon the members to be joined.

Laser beam cutting

A process that severs material with the heat from a concentrated coherent beam impinging upon the work-piece.

Gas cutting

A process that uses gases and oxygen to weld and cut metals, respectively.

Ground connection

A safety connection from a welding machine frame to the earth.

Backing Gas

A shielding gas used on the underside of a weld bead to protect it from atmospheric contamination

Friction welding

A solid welding process which produces coalescence of material by the heat obtained from a mechanically induced sliding motion between rubbing surfaces. The work parts are held together under pressure.

Friction stir welding

A solid-state welding process, which produces coalescence of material by the heat obtained from a mechanically induced rotating motion between tightly butted surfaces. The work parts are held together under pressure.

MIG welding

A subtype of GMAW that uses an inert gas or gas mixture for shielding. Typically used on aluminum and other non-ferrous metals.

Laser cutting

A technology that is used for industrial manufacturing applications and uses a laser to cut materials.

Electric Arc Welding

A type of welding that uses a welding power supply to create an electric arc between an electrode and the base material to melt the metals at the welding point.

Hertz

A unit of frequency that measures cycles per second.

Backing Weld

A weld bead applied to the root of a single groove joint to assure complete root penetration.

Slot weld

A weld between two members, one containing an elongated hole through which the other member is exposed; the hole is completely or partially filled with weld metal, thereby joining the two members; one end of the hole may be open.

Open root

A weld joint where adjacent pieces to be joined are not touching and a predefined gap or space is specified. Typically used for high strength joints that require complete penetration (i.e. the backside of the joint is welded from the front side).

Butt Weld

A weld where two pieces of metal are to be joined are in the same plane.

Backing Bar

A welding aid used to prevent melting through of a joint when performing a complete-joint penetration groove weld.

Electro-Slag Welding

A welding process that is used for welding heavy structure components.

Laser welding

A welding process that offers low heat input and minimum distortion of welded plates and stiffeners.

Chain Intermittent Weld

A welding technique where the weld is created by alternatively welding either side of the metal joint, along the entire joint

Auto-Crater

Allows a TIG (Tungsten Inert Gas) arc to crater-out, allowing time for the addition of filler, without the loss of shielding gas. Eliminates the need for a remote control at arc end.

Spot welding

Also known as "connecting", joining materials by welding at a number of separate points, usually made on materials having some type of overlapping joint design.

Intermittent Weld

Also known as stitch welding, where individual weld segments are broken up into regularly repeating weld segments rather than a continuous joint.

Grinding

An abrasive machining process that uses a grinding wheel.

Plasma-Arc Cutting (PAC)

An arc cutting process using a constricted arc to remove the molten metal with a high-velocity jet of ionized gas from the constricting orifice.

Flux-Cored Arc Welding (FCAW)

An arc welding process that produces coalescence of metals by means of tubular electrode. Shielding gas may or may not be used.

Plasma Arc Welding (PAW)

An arc welding process that uses a constricted arc between a non-consumable electrode and the weld pool (transferred arc) or between the electrode and the constricting nozzle (non-transferred arc). Shielding is obtained from the ionized gas issuing from the torch.

Gas Metal Arc Welding (GMAW)

An arc welding process where the arc is between a continuous filler metal electrode and the weld pool. Shielding from an externally supplied gas source is required.

Gas Tungsten Arc Welding (GTAW)

An arc welding process where the arc is between a tungsten electrode (non-consumable) and the weld pool. The process is used with an externally supplied shielding gas.

Electro-Gas Welding

An arc welding process, which combines features of gas and shielded welding with those of electro-slag welding.

Alternating Current (AC)

An electrical current that reverses its direction at regular intervals, such as 60 cycles alternating current (AC), or 60 hertz.

Machining

Any of various processes in which a piece of raw material is cut into a desired final shape and size by a controlled material-removal process

Edge weld

Are used where the edges of two sheets or plates are adjacent and are in approximately parallel planes at the point of welding.

Fixed automation

Automated electronically controlled welding system for simple, straight or circular welds.

Flexible automation

Automated, robotically controlled welding system for complex shape sand applications where welding paths require torch-angle manipulation.

Arc-Drive

Automatically enhances Stick welding, especially on pipe, by focusing the arc and preventing the electrode from going out.

Adaptive Hot Start

Automatically increases the output amperage at the start of a stick weld, should the start require it. Helps eliminate sticking of the electrode at arc start.

High Frequency

Covers the entire frequency spectrum above 50,000 Hz. Used in TIG welding for arc ignition and stabilization.

Direct Current (DC)

Current that flows in one direction and does not reverse its direction of flow

Active Arc Stabilizer

Enhances arc starts and provides a softer arc throughout all ranges, with less puddle turbulence and less spatter.

Power Efficiency

How well an electrical machine uses the incoming electrical power

Staggered Intermittent Weld

Making a line of intermittent fillet welds on each side of a joint in a manner such that the increments on one side are not opposite to those on the other side.

Spatter

Metal particles blown away from the welding arc. These particles do not become part of the completed weld.

Hammering

Method of finishing to flatten the weld and stretch the metal back in the desired shape.

Globular Transfer

Named for "globs" of weld metal transferring across the arc in a gravity feed. Droplets across the arc are usually larger than the electrode diameter. It does not produce a very smooth weld bead appearance, and some spatter can occur. Usually limited to the flat and horizontal welding positions, and not used on thin metals.

Spray transfer

Named for a "spray" of tiny molten droplets across the arc, usually smaller than the wire diameter. Uses relatively high voltage and amperage values, and the arc is "on" at all times after the arc is established. Very little if any spatter is produced. Usually used on thicker metals in the flat or horizontal welding positions.

Short circuit transfer

Named for welding wire touching the base metal many times per second, can be used in all welding positions and on all thicknesses of metal. Some spatter is produced.

Inverter

Power source that 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 pulse welding

Shielding gas

Protective gas used to prevent atmospheric contamination of the weld pool. Obtained from the electrode outer coating, often called flux. Filler metal is primarily obtained from the electrode core.

Pulsing

Sequencing and controlling the amount of current, the frequency and the duration of the welding arc.

Current

The amount of electricity flowing past a point in a conductor every second.

Automatic

The control of a process with equipment that requires little or no observation of the welding and no manual adjustment of the equipment controls.

Fill depth

The depth the weld penetrates the base metal.

Direct Current Electrode Positive (DCEP)

The 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. Also called direct current, reverse polarity (DCRP).

Direct Current Electrode Negative (DCEN)

The 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. Also called direct current, straight polarity (DCSP).

Root pass

The first weld bead deposited in a multiple pass weld.

Primary Power

The input line voltage and amperage available to the welding machine from the shop's main power line, single-phase or three-phase AC power expressed in watts or kilowatts (KW)

Leg size

The leg length is usually designated as the size of the weld.

Concavity

The maximum distance from the face of a concave fillet weld perpendicular to a line joining the weld toes.

Convexity

The maximum distance from the face of a convex fillet weld perpendicular to a line joining the weld toes.

Pitch

The measurement from midpoint to midpoint of intermittent welds (i.e., spacing).

Amperage (amps)

The measurement of the amount of electricity flowing past a given point in a conductor per second (i.e., current).

Finish Method

The method of surface preparation for welded items that are not to remain in an "as welded" condition.

Duty Cycle

The number of minutes out of a 10-minute time period an arc welding machine can be operated at maximum rated output.

Destructive testing

The physical destruction of the completed weld in order to evaluate its characteristics.

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.

Fillet welding

The process of joining two pieces of metal together that are perpendicular or at an angle.

Root opening

The separation between the members to be joined at the root of the joint.

Contour

The shape of the top of a finished weld.

Arrow Side

The side of the joint to which the arrow points

KVA (Kilovolt-amperes)

The total volts times amps divided by 1,000, demanded by a welding power source from the primary power furnished by the utility company.

Lift-Arc

This feature allows TIG arc starting without high frequency. Starts the arc at any amperage without contaminating the weld with tungsten.

Hot start

Used on some stick (SMAW) machines to make it easier to start difficult-to-start electrodes. Used for arc starting only

Seam welding

Welding a lengthwise seam in sheet metal either by abutting or overlapping joints.

Constant Voltage (CV), Constant Potential (CP) Welding Machine

Welding machine that maintains a relatively stable, consistent voltage regardless of the amperage output. It results in a relatively flat volt-amp curve.

Constant Current (CC) Welding Machine

Welding machine with limited maximum short circuit current. They have a negative volt-amp curve and are often referred to as "droopers."

Semiautomatic Welding

Welding where the equipment controls only the electrode wire feeding. The welding gun movement is controlled by hand.

Gas welding

Welding with the heat from an oxy-fuel flame, with or without the addition of filler metal or pressure.