Welding Terms and Glossary
Acceptable Weld is a weld that meets the applicable requirements.
Aluminum Pulse, GMAW aluminum welding results can be improved over traditional DC positive aluminum MIG welding. It is possible with the help of the Lincoln Electric Power Wave® Advanced Module. By switching the polarity of the arc, heat input is reduced, and deposition rates are enhanced.
Accu-Pulse® is a MIG welding process that delivers precise control of the arc even over tack welds and in tight corners. It provides optimum and precise molten puddle control. A Miller Technology Exclusive.
Accu-Rated™ Power is a standard for measuring engine-driven generator power and guarantees delivery of all power promised. A Miller Technology Exclusive.
Across the Arc Wire Feeders is also referred to as voltage-sensing wire feeders. The wire feeder is powered by the welding cable instead of a control cable. It provides the benefit of fewer cables running back to the power source. Voltage control at the point of use is not possible without the addition of a control cable, however, technologies such as ArcReach and CrossLinc now provided remote control capability via the welding cable.
AC-STT® is based on Lincoln Electric’s patented STT® process. AC-STT® combines the proven spatter reducing technology of the STT® waveform with the balanced heat-input characteristics of AC GMAW. It produces an advanced short circuit process optimized specifically for thin-gauge materials.
Active Arc Stabilizer™ is a Miller Technology Exclusive – Active Arc Stabilizer which enhances arc starts and provides a softer arc throughout all ranges, with less puddle turbulence and less spatter.
Active Fluxes are restricted to single or minimal multi-pass welding. They produce changes in weld metal chemistry when welding is changed.
Actual Throat is the shortest distance from the root of a fillet weld to its face.
Adaptive Hot Start™ increases automatically the output amperage at the start of a stick weld. It helps to eliminate the sticking of the electrode at arc start. A Miller Technology Exclusive. Available on these machines: 12VX Extreme Duty, EXtreme 360 MAP, Miller Syncrowave 250 DX, Miller Syncrowave 350 LX, Miller XMT 350 MPa.
Advanced Active Field Control Technology™ is a simple and reliable patented way of accurately controlling an engine drive’s generator weld output. A Miller Technology Exclusive.
Aging is a process of holding metals or alloys at room temperature. After subjecting them to shaping or heat treatment for the purpose of increasing dimensional stability or to improve their hardness and strength through structural changes.
Air Carbon Arc Cutting It is a carbon arc cutting process variation that removes molten metal with a jet of air.
Air Hardening is a characteristic of steel that becomes partially or fully hardened (martensitic) when cooled in the air from above its critical point.
AISI stands for American Iron and Steel Institute
Allotropic is a material in which the atoms can transform into two or more crystalline structures at different temperatures.
Allotropic Change is a change from one crystal structure of the metal to another that has different physical properties.
Alloy is a mixture of metallic elements with specific properties such as greater resistance to corrosion or improved strength. E.g. brass is an alloy of copper and zinc; steel is an alloy of iron and carbon.
All-weld-metal Test Specimen is a test specimen with the reduced section composed wholly of weld metal.
Alternating is an electrical current that alternately travels in either direction in a Current conductor. In 60 cycles per second (60 Hz) AC, the frequency used in the U.S.A., the current direction reverses 120 times every second.
Alternating Current (AC) is an electric current that periodically reverses direction. The power which is delivered to businesses and residences is of AC type.
Aluminum Pulse Hot Start™ is a Miller Technology Exclusive, that automatically provides more arc power to the Millermatic® 350P to eliminate a “cold start”.
Amperage is a measurement of the amount of electricity flowing past a given point in a conductor per second. Amperage is also known with a popular name ‘current’.
Ampere is a unit of electrical rate of flow. And an amperage is commonly referred to as the “current” in an electrical circuit.
Anneal is the process of heating a metal to a temperature below the critical range. And it is followed by a relatively slow cooling cycle to induce softness and remove stresses.
Annealing is subjected to heat treatment. Usually, it involves heating, relatively slow cooling of metals or alloys for the purpose of decreasing hardness and increasing the ease of machining or the cold-working characteristics. Annealing may be used to the following:
(i) to remove the effects of strain hardening resulting from cold work
(ii) to remove stresses found in castings, forgings, weldments and cold-worked metals
(iii) to improve machinability and cold-working characteristics
(iv) to improve mechanical and physical properties by changing the internal structure, and to increase the uniformity of the structure and correct segregation, banding, and other structural characteristics.
Arbide is a chemical combination of carbon with some other elements.
Arc is a physical gap between the end of the electrode and the base metal. The gap causes heat due to the resistance of current flow and arc rays.
Arc Blow is a deflection of an electric arc from its normal path due to magnetic forces.
Arc Blow is a process in which welding with direct current may set up a magnetic field in the steel plate being welded. This magnetic field causes the arc creating difficulty in controlling, and flutter and blow the arc.
Arc Energy is a reference to burn-off characteristics. Moderate arc energy is typical of Atom Arc. A 316L electrode has lower arc energy than a 7018 whereas a 6010 has more.
Arc Force is a temporary increase in the output current during welding when the arc is too short. It prevents the electrode from sticking during welding. In order to produce an outstanding weld performance on a variety of electrodes (rutile, basic or cellulose), the arc force can be finely adjusted with a simple knob.
Arc Length is a distance from the electrode to the attachment point on the workpiece.
Arc Seam Weld is a seam weld made by an arc welding process.
Arc Spot-Weld is a spot weld made by an arc welding process.
Arc Time is the time during which an arc is maintained in making an arc weld.
Arc Voltage is a voltage across the welding arc.
Arc Weld Deposition Efficiency is a ratio of the weight of filler metal (expressed in percent) deposited in the weld to the weight of filler metal melted.
Arc Welding is a group of welding processes that produce coalescence of workpieces by heating them with an arc. The processes are used with or without the application of pressure and with or without filler metal.
Arc Welding Electrode is a component of the welding circuit through which the current is conducted between the electrode holder and the arc.
Arc Welding Gun is a device used to transfer current to a continuously fed consumable electrode, guide the electrode, and direct the shielding gas.
Arc Welding Torch is a device used to transfer current to a fixed welding electrode, position the electrode and direct the flow of shielding gas.
Arc-Drive automatically enhances Stick welding, especially on pipe, by focusing the arc and preventing the electrode from going out. A Miller Technology Exclusive.
ArcReach is a technology developed by Miller Electric. It provides the ability for a welding operator to make parameter adjustments at the wire feeder. It is done without the need for control cords or specialized wireless remotes. Using existing welding cables, voltage changes are communicated from the wire feeder to the power source.
As Cast Structures is a crystalline structure before stress relief through rolling or hammer forging.
As-Welded is pertaining to the condition of weld metal, welded joints, and weldments after welding. But it happens prior to any subsequent thermal, mechanical or chemical treatments.
ASME stands for American Society of Mechanical Engineers
ASTM stands for American Society for Testing and Materials
Atom is the smallest particle of an element that possesses all the characteristics of the very element. An atom consists of protons, neutrons, and electrons.
Austenite is a high-temperature crystal structure of carbon steel or the room temperature structure of chrome-nickel steel.
Auto Remote Sense™ is a process that automatically switches machines from panel to remote control with remote connected. Available on Dimension™ NT 450, XMT® 350, Trailblazer® Series, and PRO 300. Eliminates confusion and the need for panel/remote. A Miller Technology Exclusive
Auto-Crater™ is a Miller Technology Exclusive and allows a TIG arc on the Trailblazer® Series to crater-out, allowing time for the addition of filler, without the loss of shielding gas. It eliminates the need for remote control at the arc end.
Autogenous Weld is a fusion weld made without the addition of filler metal.
Auto-Line™ is a Miller Technology Exclusive. It allows for any primary input voltage within a range, single- or three-phase, 50 or 60 Hz. It also adjusts for voltage spikes within the entire range.
Auto-Link® is an internal inverter power source circuit. It automatically links the power source to the primary voltage being applied (230 V or 460 V), without the need for manually linking primary voltage terminals. (A Miller Technology Exclusive).
Automatic Start at Idle (Miller Technology Exclusive) idles engine immediately when started, extending engine life and reducing fuel consumption and noise.
Automatic Welding is a process using equipment that welds without the constant adjusting of controls by the welder or operator. Equipment controls joint alignment by using an automatic sensing device.
Auto-Refire™ is a Miller Technology Exclusive. It automatically controls the pilot arc when cutting expanded metal or multiple pieces of metal, without manual re-triggering.
Auto-Stop™ (A Miller Technology Exclusive) allows a TIG arc to be stopped without the loss of shielding gas on the Trailblazer® Series.
Axcess™ File Management is a software turning a standard Palm handheld into a data card and a remote pendant for all axess systems. It allows emailing, storage and transfer of welding programs. (A Miller Technology Exclusive).
Axis of a Weld is a line through the length of a weld. It is perpendicular to and at the geometric center of its cross-section.
Back Gouging is the removal of weld metal and base metal from another side of a partially welded joint. It is to assure complete penetration upon subsequent welding from that side.
Backhand Welding is a welding technique in which the welding torch or gun flame is directed towards the finished weld. In GMAW and FCAW, sometimes, it is referred to as the “pull gun technique”.
Backing is a material (either a base metal, weld metal, carbon, or granular material) placed at the root of a weld joint. It is done for the purpose of supporting molten weld metal.
Backing Pass is a pass made to deposit a baking weld.
Backing Ring is backing in the form of a ring and generally used in the welding of pipe.
Backing Strip is backing in the form of a strip.
Backstep Sequence is a longitudinal sequence in which the weld bead increments are deposited in the opposite direction to the progress of welding the joint. See cascade sequence, block sequence, joint building sequence, continuous sequence, and longitudinal sequence.
Bare Electrode is a filler metal electrode carrying inside a single metal or alloy that has been produced into a wire, strip, or bar form. It has had no coating or covering applied to it other than that which was incidental to its manufacture or preservation.
Bare Metal Arc Welding (BMAW) is an arc welding process that produces coalescence of metals by heating them with an electric arc between a bare or lightly coated metal electrode and the work. Neither shielding nor pressure is used and filler metal is obtained from the electrode. (This is an obsolete process now in industrial applications).
Base Metal is the metal or alloy that is welded, brazed, soldered, or cut.
Base Metal Test Specimen is a test specimen composed wholly of base-metal.
Bevel is an angular type of edge preparation.
Bevel Angle is an angle formed between the prepared edge of a member and a plane perpendicular to the surface of the member. It is also referred to as a cut angle.
Bevel Cutting is a plasma arc cutting technique which uses a tilted torch to produce an angle on the edge of parts being cut.
Bevel Groove Weld is a type of groove weld.
Binary Alloy is an alloy composed of two elements.
Blind Joint is a joint, no portion of which is visible.
Block Sequence is a combined longitudinal and buildup sequence for a continuous multiple-pass weld in which separated lengths are completely or partially built up in cross-section before intervening lengths are deposited.
Blowhole is a defect in the metal caused by hot metal cooling too rapidly when excessive gaseous content is present. In welding, a gas pocket in the weld metal resulting from the hot metal solidifying without all the gases having escaped to the surface.
Bonded Fluxes are manufactured by binding an assortment of powder together and then baking at a low temperature. The plus point is that additional alloying ingredients can be added to the mixture.
Boxing is a continuation of a fillet weld around a corner of a member as an extension of the principal weld.
Braze is a weld produced by heating an assembly to the brazing temperature using a filler metal. It is having a liquidus above 450°C (840°F) and below the solidus of the base metal.
Brittleness is a tendency of a material to fail suddenly by breaking, without any permanent deformation of the material before failure.
Buildup is a surfacing variation in which surfacing material is deposited to achieve the required dimensions. There are other terms also such as buttering, cladding, and hard-facing.
Burn-thru is a term erroneously used to denote excessive melt-thru or a hole; a seam weld or spot weld.
Butt Joint or Butt-Weld, it is a joint between two members aligned approximately in the same plane.
Buttering is a form of surfacing in which one or more layers of weld metal are deposited on the groove face of one member (for example, a high alloy weld deposit on steel base metal which is to be welded to dissimilar base metal). The buttering imparts a suitable transition weld deposit for subsequent completion of the butt weld.
Button is a part of the weld, including all or part of the nugget. It tears out in the destructive testing of spot, seam, or projection welded specimens.
Carbide is a chemical combination of carbon with some other elements. A metallic carbide takes the form of very hard crystals.
Carbide Precipitation is a formation of chromium carbide in austenitic stainless steel which allows inter-granular corrosion in corrosive service.
Carbon Arc Cutting (CAC) is an arc cutting process in which metals are severed by melting them with the heat of an arc between a carbon electrode and the base metal.
Carbon Arc Welding (CAW) is an arc welding process that produces coalescence of metals by heating them with an arc between a carbon electrode and the work. In the process. no shielding is used, and pressure and filler metal may or may not be used.
Carbon Electrode is a non-filler material electrode used in arc welding or cutting, consisting of a carbon or graphite rod, which may be coated with copper or other coatings.
Carbon Steel, the physical properties of steel are chiefly the result of the percentage of carbon contained in it. The iron-carbon alloy in which the carbon is the most important constituent, ranging from 0.04%-1.40%. It is also referred to as plain carbon steel or straight carbon steel. Along with this, some minor elements also present in carbon steel such as manganese, phosphorus, sulfur, and usually silicon.
Cascade Sequence is a combined longitudinal and buildup sequence. The weld beads are deposited in overlapping layers during this.
Casehardening is a heat-treatment process applied to steel or iron-carbon alloys, by which a harder outside is obtained over a softer interior; depth or increased hardness depends upon the length of treatment.
Cast of Continuous Welding Electrodes is the diameter of the circle; a length of the electrode assumes when lying free on a smooth surface.
Cast Steel is molten steel cooled and solidified in a mold.
Cellulose is a chemical of carbon, hydrogen, and oxygen. it consists of wood pulp or flour as used in mild steel electrode coatings.
Cementite is a chemical compound of iron and carbon, also called iron carbide, containing 93.33% iron combined with 6.67% carbon by weight. The chemical formula for cementite is Fe3C.
Center of Gravity (weld positioning) is the point at which the weldment balances on all axes equally. More torque is applied to the positioner, as the distance increases from the device. As the welder adds material and parts to the positioner, the center of gravity changes.
Chain Intermittent Fillet Welding, they are two lines of intermittent fillet welds on a joint. In both the fillet weld increments on one side which are approximately opposite to those on the other side of the joint.
Chip Test is a test used to identify a metal. The metal is chipped off using a cold chisel and hammer. The resulting underlying pattern in the metal is unique to several classes of ferrous metals.
Chopper is a high-performance plasma arc power source design that uses semiconductor switching techniques.
Clad Metal is a composite metal that contains two or three layers welded together. The welding may have been done by roll welding, arc welding, casting, heavy chemical deposition or heavy electroplating.
Cladding/ Coating is a relatively thick layer (> 1 mm (0.04 in.) of material applied by the surfacing of the purpose of improved corrosion resistance or other properties. Simply, it is a surfacing variation that deposits or applies surfacing material usually to improve corrosion or heat resistance.
Clear Puddle is a puddle that is not crowded by slag or an erratic arc.
Coalescence is growing together or growth into one body of the materials being welded.
Coating Concentricity refers to an equal coating thickness on the core wire/rod.
Coefficient of Friction is a value used in engineering calculations. And it is an indicator of the ability of one material to slide on another. The low coefficient of friction means a low rate of wear between sliding surfaces.
Coil with Support is a filler metal package type that consists of a continuous length of the electrode in coil form wound on internal support. It is a simple cylindrical section without flanges.
Cold Drawing/ Rolling reduces the cross-section of metal by pulling it through a die while its temperature is below the re-crystallization temperature.
Cold Working is a permanent deformation or crystal distortion of a metal below its lowest temperature of recrystallization, resulting in work hardening.
Complete Fusion is a fusion which happens over the entire base material surfaces intended for welding, and between all layers and passes.
Complete Joint Penetration is a joint root condition in a groove weld in which the weld metal extends through the joint thickness.
Composite Electrode is a filler metal electrode used in arc welding, which consists of more than one metal component combined mechanically. It may include materials that protect the molten metal from the atmosphere, improve the properties of the weld metal or stabilize the arc.
Composite Joint is a joint produced by welding which is used in conjunction with a non-welding process.
Compressive Strength is the resistance of a material to a force that is tending to deform or fail it by crushing.
Concave Fillet Weld is a weld having a concave face.
Concave Root Surface is a surface with a concave face.
Concavity, it is the maximum distance from the face of a concave fillet weld perpendicular to a line joining the toes.
Concurrent Heating is an application of supplemental heat to a structure during a welding or cutting operation.
Conductor is a material that has a relatively large number of loosely bonded electrons. It may move freely when the voltage (electrical pressure) is applied. E.g. Metals are good conductors.
Constant Current (welding machines) is a welding power source that will produce a relatively small change in amperage despite changes in voltage caused by a varying arc length used mostly for welding with coated electrodes.
Constant Current Power Source is an arc welding power source with a volt-ampere relationship yielding a small welding current change from a large arc voltage change.
Constant Speed Wire Feeders is a constant speed wire feeder employed with a constant voltage (CV) power source. The arrangement requires an extra control cord between the wire feeder and the power source. This allows operators to control both voltage and wire feed speed (amperage) at the feeder, a big benefit when working remotely. The voltage and amperage values remain constant unless manually adjusted, and both can be adjusted independently of each other
Constant Voltage (welding machines) is a welding power source producing a relatively small change in voltage when the amperage is changed substantially. It is used mostly for welding with solid or flux-cored electrodes.
Constricted Arc is a plasma arc column, shaped by the constricting orifice in the nozzle of the plasma arc torch or plasma spraying gun.
Consumable Guide Electro Slag Welding is a method of electro slag welding. In it, the filler metal is supplied by an electrode and its guiding member.
Consumable Insert is a preplaced filler metal. It is completely fused into the root of the joint and becomes part of the weld.
Consumables are parts of the Torch that eroded or otherwise worn during normal cutting or gouging operations, such as, electrodes, nozzles, shields, caps and swirl rings.
Contact Tip is a part of a gas metal arc welding gun or flux-cored arc welding gun. It transfers the welding current to the welding wire immediately before the wire enters the arc.
Contact Tube is a device that transfers current to a continuous electrode.
Contact Tube Setback is the distance from the contact tube to the end of the gas nozzle.
Continuous Sequence is a longitudinal sequence in which each pass is made continuously from one end of the joint to the other.
Continuous Weld is a weld that extends continuously from one end of a joint to the other. It extends completely around the joint where the joint is essentially circular.
Convex Fillet Weld is a fillet weld having a convex face.
Convex Root Surface is a convex root surface.
Convexity is a maximum distance from the face of a convex fillet weld perpendicular to a line joining the toes.
Cool-On-Demand™ is an integrated cooler runs only when needed on Syncrowave® 250 DX and 350 LX. A Miller Technology Exclusive.
Corner Joint, it is the joint between two members located approximately at right angles to each other.
Corner-flange Weld is a flange weld with only one member flanged at the location of welding.
Cover Lens/ Plate (eye protection) is a removable pane or colorless glass either a plastic-coated glass or plastic that covers the filter plate and protects it from weld spatter, pitting, or scratching. It is used in a helmet, hood or goggle.
Covered Electrode is a composite filler metal electrode that consists of a core of a bare electrode or metal cored electrode, covering with a slag layer on the weld metal. The covering may contain materials providing such functions as shielding from the atmosphere, de-oxidation, and arc stabilization, and can serve as a source of metallic additions to the weld.
Crack is a fracture-type discontinuity featured by a sharp tip and high ratio to length and width to opening displacement.
Crater is a depression at the termination of a weld bead or in the molten weld pool.
Crater Crack is a crack in the crater of a weld bead.
Creep is a slow deformation (e.g. elongation) of metal under prolonged stress. Not to be confused with deformation which results immediately upon application of a stress.
Critical Cooling Rate is the rate of cooling that is fast enough to transform austenite into 100% martensite.
CrossLinc is a technology developed by Lincoln Electric. It provides the ability for the operator to adjust the voltage at the wire-feeder without the need for an additional control cable or wireless remote. The voltage changes are communicated from the wire feeder to the power source using existing welding cables.
Cryogenic Temperatures are the extremely low temperatures usually associated with liquified gases in the range of -100°F to -400°F.
Current is another name for amperage or the amount of electricity flowing past a point in a conductor every second.
Current (Weld) is the amount of electric charge flowing past a specified circuit point per unit time Current. It is the main parameter for welding and must be chosen to plate thickness and welding speed with respect to the weld quality. The weld current affects penetration and deposition rate. A high current result in a higher and narrower weld with greater penetration depth. If there is too high welding current, it can result in undercuts, an uneven weld convexity, burn-through, thermal cracking, and inappropriate merging angle with the body material and undercutting.
Current Density is a measure of the degree of arc constriction that is achieved with a plasma torch. The high current density results in a high electrode melt-off rate and a concentrated, deep penetrating arc.
Cut Angle/ Bevel Angle is an angle formed between the cut surface and a theoretical plane perpendicular to the plate surface. The plasma arc cutting tends to remove more metal from the top than from the bottom, making a cut angle.
Cutting Gas/ Plasma Gas/ Orifice Gas is a gas-directed into the torch to surround the electrode. It becomes ionized by the arc to form a plasma and issues from the torch nozzle as a plasma jet.
CV is a conventional mode for the MIG welding process. It is a general-purpose MIG welding mode that uses constant voltage for short arc, globular and sprays transfer.
Cylinder is a portable container that is used for transportation and storage of compressed gas.
Cylindrical Nozzle Design is a simple cylindrical metering orifice that is operated at 25-60 psig depending on the manufacture.
DCEN is an arrangement of direct current arc welding leads, in which the electrode is the negative pole and workpiece is the positive pole of the welding arc.
DCEP is an arrangement of direct current arc welding leads, in which the electrode is the positive pole and the workpiece is the negative pole of the welding arc.
Defect is a discontinuity or discontinuities which by nature render a part or product unable to meet minimum applicable acceptance standards or specifications. The term is called ‘reject-ability’.
Defective Weld is a weld that contains one or more defects.
Deoxidizers are the following elements such as aluminum, titanium, manganese, silicon, and zirconium are deoxidizers. They are used in welding electrodes and wires to prevent oxygen from forming harmful oxides and porosity in the weld metal.
Deposited Metal is a filler metal that has been added during welding, brazing or soldering processes.
Deposition Efficiency (arc welding) is the ratio of the weight of deposited metal to the net weight of filler metal consumed, exclusive of stubs. E.g. DE = Weight of Weld Metal ÷ Weight of Electrode Used
Deposition Rate is the weight of weld metal deposited and compared to the time of welding. It is usually expressed in pounds per hour.
Depth of Bevel is the perpendicular distance from the base metal surface to the root edge or the beginning of the root face.
Depth of Fusion is the distance that fusion extends into the base metal or previous bead from the surface melted during welding.
Dig/ Arc Control gives a power source variable additional amperage during low voltage (short arc length) conditions during welding. It helps to avoid “sticking” stick electrodes when a short arc length is used.
Digging refers to the arc characteristics normally seen with a 6010 electrode. A “digging” arc is the one in which there is a parent metal being penetrated at the arc.
Dilution is the change in the chemical composition of a welding filler material. It is caused by the admixture of the base material or previously deposited weld material in the deposited weld bead. Normally, it is measured by the percentage or base material or previously deposited weld material in the weld bead.
Direct Current (DC) is an electrical current that flows in only one direction in a conductor. And the direction of current depends upon the electrical connections to the battery or other DC power source. The terminals on all DC devices are usually marked (+) or (-). And reversing the leads will reverse the direction of current flow.
Direct Current Electrode Negative is an arrangement of direct current arc welding leads, in which the work is the positive pole and the electrode is the negative pole of the welding arc.
Direct Current Electrode Positive is an arrangement of direct current arc welding leads, in which the work is the negative pole and the electrode is the positive pole of the welding arc.
Discontinuity is an interruption of the typical structure of a material, for example, a lack of homogeneity in its mechanical, metallurgical, or physical characteristics. A discontinuity is not necessarily a defect.
Distortion is the fusion welding method that produces the weld by moving a molten pool along the weld joint. And if the heated metal cools the shrinkage introduces distortion in (a change in shape) the welded structure.
Divergency is the tapered part of the oxygen bore directly behind the throat in high pressure (high speed) nozzle designs. Divergency allows the high pressure to become close to atmospheric before it leaves the nozzle. It increases the stream velocity and improves cut quality by keeping stream uniform. The increased velocity produces 10–15% higher cutting speeds.
Double Arcing is a condition, where the welding or cutting arc of a plasma arc torch does not pass through the constricting orifice, but transfers to the inside surface of the nozzle. Then, a secondary arc is simultaneously established between the outside surface of the nozzle and the workpiece.
Double-welded Joint is any joint welded from both sides in arc and oxyfuel gas welding,
Downhill is welding with a downward progression.
Drag is the offset distance between the entrance and exit points of the gas stream on the plate being cut and measured on the cut edge. Drag increases and decrease with varying conditions such as speed, oxygen pressure, plate thickness, oxygen purity, etc.
Drag Angle is the travel angle when the electrode is pointing backward. It can be used to define the position of welding torches, high energy beams, welding rods, welding guns, thermal cutting, and spray guns.
Drop-thru is an undesirable sagging or surface irregularity. It is encountered when brazing or welding near the solidus of the base metal caused by overheating with rapid diffusion or alloying between the filler metal and the base metal.
Dross is a re-solidified molten metal and oxides adhering to the top or bottom edge during thermal cutting.
Drum is a filler metal package type consisting of a continuous length of electrode wound or coiled within an enclosed cylindrical container.
Dual Power Option™ is a Miller Technology Exclusive which gives the option on the PipePro® 304 engine drive to use 230-volt single- or three-phase electric input power, eliminating engine wear, noise, and emissions, as well as fuel costs.
Ductility is the ability of a material to become permanently deformed without failure.
Duty Cycle is a power source specification that describes the percentage of time (usually 10 min.) that a system can be operated at a given current level.
Eccentricity (weld positioning) is the distance from the weldment center of gravity to its rotation axis in the case of an unbalanced load.
Edge Flange Weld is a flange weld with two members flanged at the location of welding.
Edge Joint is a joint between the edges of two or more parallel or nearly parallel members.
Edge Preparation is the preparation of the edges of the joint members, either by plating, cutting, cleaning or other means.
Edge Weld is a weld and called an edge point.
Effective Length of Weld is the length of a weld throughout which the correctly proportioned cross-section exists. While in a curved weld, it shall be measured along the axis of the weld.
Effective Throat is a minimum distance minus any reinforcement from the root of a weld to its face.
Elastic Limit is the maximum stress to which a material can be subjected without permanent deformation or failure by breaking.
Elasticity is the ability of a material to return to original shape and dimensions after a deforming load has been removed.
Electrical Stick-out is the distance from the contact tip to the un-melted electrode end in any welding process using solid or flux-cored wire. Sometimes it is called the “amount of wire in resistance”. The distance influences penetration, melt-off rate, and weld bead shape.
Electrode is the part of a plasma arc torch from which arc current is emitted.
Electrode Coating is the mixture of chemicals, minerals and metallic alloys that applied to the core wire. The coating controls the welding current and the welding position. It provides a shielding atmosphere, deoxidizers to clean the weld metal, and the welding slag which absorbs impurities from the weld metal. It helps to shape the weld bead and becomes an insulating blanket over the weld bead.
Electrode Core Wire is the steel wire for which the coating is applied. The diameter of the core wire is determined by the electrode size.
Electrode Extension is the length of an electrode extending beyond the end of the contact tube in GMAW, FCAW and SAW.
Electrode Holder is a device used for mechanically holding and conducting current to an electrode during welding or cutting.
Electrode Lead is an electrical conductor between the electrode holder and the source of the arc welding current.
Electrons are negatively charged particles that revolve around the positively charged nucleus in an atom.
Electroslag Welding (ESW) is a welding process that produces coalescence of metals with molten slag. It melts the filler metal and the surfaces of the work to be welded. The molten weld pool is shielded by the slag. The process starts with an arc which heats the slag. The arc is then extinguished, and the conductive slag is maintained in a molten condition by its resistance to electric current passing between the electrode and the work.
Electroslag Welding Electrode is a filler metal component of the welding circuit through which the current is conducted between the molten slag and the electrode guiding member. A consumable guide may also be used as part of the electro-slag welding electrode system.
Element is a substance that cannot be broken down into two other substances. Everything on Earth is a combination of such elements, of which there are only 103.
Elongation is a permanent elastic extension by which a metal undergoes during tensile testing. The amount of elongation is usually indicated by the percentage of an original gage length.
Emissive Electrode is a filler metal electrode that consists of a core of a bare electrode or a composite electrode to which a very light coating has been applied to produce a stable arc.
Endurance Limit is the maximum stress that a material will support indefinitely under variable and repetitive load conditions.
Engine Save Start™ idles engine three-four seconds after starting on Trailblazer® 275 DC and 302. It is a Miller Technology Exclusive which extends engine life and reduces fuel consumption.
Erratic is a situation when the arc or burn-off characteristics are not smooth and difficult to handle. Cannot control where the puddle goes.
Eutectic Alloy is a composition that solidifies at a lower temperature than the individual elements of the alloy. It freezes or solidifies at a constant temperature to form a fine mixture of crystal made up of two or more phases.
Exhaust Booth is a mechanically ventilated, semi-enclosed area in which an air-flow across the work area. It is used to remove fumes, gases, and material particles.
Extrusion is a forcing plastic metal through a die to produce a new form.
Face is a part of the weld bead between the “toes”.
Face Bend Test is a test in which the weld face is on the convex surface of a specified bend radius.
Face of Weld is the exposed surface of a weld on the side from which welding was done.
Face Reinforcement is the weld reinforcement on the side of the joint from which welding was done.
Face Shield (eye protection) is a device positioned in front of the face, whose predominant function is the protection of the eyes and face.
Fan-On-Demand™ is an internal power source cooling system, a Miller Technology Exclusive. It works when needed, keeping internal components cleaner.
FasTip™ Contact Tip is a Miller Technology Exclusive and patented, single-turn for a quick change, no tools needed.
Fatigue Failure is the cracking, breaking or another failure of material as the result of repeated or alternating stressing below the material’s ultimate tensile strength.
Fatigue Limit is the maximum stress that a material will support indefinitely under variable and repetitive load conditions.
Fatigue Strength is the resistance of material for repeating or alternating stressing without failure.
Faying Surface is the mating surface of a member that is in contact or in proximity with another member to which it is to be joined.
Feed Rate is a rate at which material passes through a gun in a unit of times.
Ferrite is the normal crystal structure of low carbon steel at room temperature.
Ferrite in Austenitic Stainless Steel is the magnetic finely dispersed crystal structure in austenitic steels that causes the austenite grains to become smaller and crack resistant.
Ferrite Number (industry-accepted figures) is an arbitrary, standardized value designating the ferrite content of an austenitic stainless steel weld metal. It is approved by the Welding Research Council (WRC) and the American Welding Society (AWS), etc.
Ferrous that contains iron. Examples are carbon steel, low alloy steels, and stainless steel.
Filled Weld is a position in which welding is performed on the upper side of an approximately horizontal plane and the face of the weld lies in an approximately vertical plane.
Filler Metal is a metal or an alloy to be added in making a welded, brazed and soldered joints.
Filler Wire is a filler metal that is supplied as a wire on spools or reels. The material of wire and diameter may vary depending on the welding application.
Fillet Weld is an approximately triangular cross-section weld that joining two surfaces nearly at right angles to each other in a lap joint, T-joint or corner joint.
Fillet Weld Leg is a distance from the joint root to the toe of the fillet weld.
Fillet Weld Size is for the equal leg fillet welds. The leg lengths of the largest isosceles right triangle that can be inscribed within the fillet weld cross-section.
For an unequal leg fillet welds, the leg lengths of the largest right triangle that can be inscribed within the fillet weld cross-section.
Filter Lens/Plate is around the filter plate for eye protection from excessive ultraviolet, infrared and visible radiation.
Fines are about any or all material finer than a mesh under consideration.
Fissure is a small crack-like discontinuity with only slight separation (opening displacement) of the fracture surfaces. And the prefixes macro or micro indicate relative size.
Fixed Automation is an automated, electronically controlled welding system for simple, straight or circular welds.
Fixture is a device that is designed to hold parts to be joined in proper relation to each other.
Flame Spraying (FLSP) is a thermal spraying process using an oxy/fuel gas flame and is a source of heat for melting the surfacing material.
Flange Weld (size of weld) is the thickness of a weld metal that is measured at the root of the weld.
Flashback is the situation when gases ‘flashback’ the flame regresses from outside (off) the tip in use into the torch body itself. That flame heads to the point where the gases are mixed. The flame will continue to burn at that mixing point as long as fuel and oxygen are present and allowed to flow.
Flat Welding Position is a welding position used to weld from the upper side of the joint and the face of the weld is approximately horizontal.
Flaw is a near-synonym for discontinuity but with an undesirable connotation.
Flexible Automation is an automated, robotically controlled welding system for complex shapes and applications where welding paths require torch-angle manipulation.
Flowability is the ability of molten filler metal to flow or spread over a metal surface.
Flux is the material used to prevent, dissolve or facilitate removal of oxides and other undesirable surface substances. The flux also serves to reduce spatter and contributes to weld bead shape.
Flux Cored Arc Welding (Electro-gas) is a variation of the flux-cored arc welding process. It uses molding shoes to confine the molten weld metal for vertical position welding.
Flux Cored Electrodes is a composite tubular filler metal electrode that consists of a metal sheath and a core of various powdered materials, producing an extensive slag cover on the face of a weld bead.
Flux Voids is a section of a flux cored electrode which contains no flux. In low alloy types, voids can cause serious problems.
Flux-Cored Arc Welding (FCAW) is an arc welding process using a spooled, tubular filler metal electrode consumable enveloping flux. The shielding is obtained from the flux contained within the electrode core.
Forehand Welding is a welding technique in which the gun flame or welding torch is directed away from the finished weld.
Forging is a deforming into a new shape by compressive force.
Friction Stir Welding is a process in which metals are welded together by the friction created by a rotating tool. It only softens but does not melt the metal. No metal is cut.
Fuel Efficiency is the factor relating to the volume of fuel in cubic foot needed to duplicate the efficiency of acetylene which is designated as 1.0 cubic foot.
Full Annealing is the heating of steels or iron alloys to above their critical temperature range. It is soaking at the annealing temperature until they are transformed into a uniform austenitic structure, followed by cooling. Generally, the cooling rate is relatively slow.
Full Fillet Weld is a weld with a size equal to the thickness of the thinner member joined.
Fumes are the airborne solid particulate matter emitted during welding or cutting processes. Fume particles are usually sub-micron in size and thus tend to remain airborne and drift with the air currents.
Fused Fluxes are the melted ingredients that have been chilled and ground to particle size. This type of flux has low moisture pick-up and improved recycling capabilities.
Fusion is a process of melting together of filler metal and base metal (substrate), or of base metal only resulting in coalescence.
Fusion Face is a surface of the base metal which melts during the welding process.
Fusion Welding is any method or welding process, or which uses fusion to complete the weld.
Fusion Zone is the area of base metal melted as determined on the cross-section of a weld.
Galling is the condition between rubbing surfaces where high spots or protrusions on a surface become friction welded to the mating surface.
Gas Ions, in the presence of an electrical current, shielding gas atoms lose one or more electrons and then carry a positive electrical charge. It provides a more electrically conductive path for the arc between the electrode and the workpiece.
Gas Metal Arc Welding (GMAW) is an arc welding process, producing coalescence of metals by heating them with an arc between a continuous filler metal (consumable) electrode and the piece of work. Shielding is obtained from an externally supplied gas or gas mixture.
Gas Metal Arc Welding Short-Circuiting Arc (GMAW-S) is a variation of the gas metal arc welding process. In this process, the consumable electrode is deposited during repeated short circuits.
Gas Metal Arc Welding-Electro-gas (GMAW-EG) is a variation of the gas metal arc welding process which uses molding shoes to confine the molten weld metal for vertical position welding.
Gas Metal Arc Welding-Pulsed Arc (GMAW-P) is a variation of the gas metal arc welding process in which the current is pulsed.
Gas Nozzle is a device at the exit end of the torch or gun that directs shielding gas to the point of welding.
Gas Regulator is a device for controlling the delivery of gas at some substantially constant pressure.
Gas Shielding Arc Welding is a general term for gas metal arc welding, gas tungsten arc welding, and flux-cored arc welding when gas shielding is employed.
Gas Tungsten Arc Welding (GTAW/TIG) is an arc welding process producing coalescence of metals by heating them with an arc between a tungsten (non-consumable) electrode and the work. The shielding is obtained from a gas or gas mixture. Pressure may or may not be used and filler metal may or may not be used.
Gas Tungsten Arc Welding-Pulsed Arc (GTAW-P) is a TIG variation of the gas tungsten arc welding process in which the current is pulsed.
Globular is the arc transfer when you can see the globules burning off and falling into the puddle as opposed to a ‘smooth arc’.
Globular Transfer (arc welding) is a type of metal transfer where the molten filler metal is transferred across the arc in large droplets.
Goat is a nickname for Lincoln Electric’s LT7 submerged arc tractor.
Gouging is the forming of a bevel or groove by material removal.
Gray Iron is a cast iron with 2%-4% carbon. The carbon is mostly in the form of graphite.
Groove Angle is the ‘total included angle of the groove between workpieces.
Groove is an opening or channel in the surface of a part or between two components which provides space to contain a weld.
Groove Angle is the total included angle of the groove between parts to be joined by a groove weld.
Groove Face is the surface of a member included in the groove.
Groove Radius is the radius used to form the shape of a J- or U-groove weld joint.
Groove Type is the geometric configuration of a groove.
Groove Weld is a weld, made in the groove between two members to be joined. For examples are double-V-groove weld single-bevel-groove weld, double-bevel-groove weld, double-flare-bevel-groove weld, double-flare-V-groove weld, single-flare-bevel-groove weld, double-U-groove weld, square-groove weld, double-J-groove weld, single-U-groove weld, single-flare-V-groove weld single-J-groove weld, and single-V-groove weld.
Ground Connection is a safe connection from a welding machine frame to the earth.
Ground Lead is a reference for connection from the welding machine to the work.
Gun-On-Demand™ is a Miller Technology Exclusive allowing either to use as a standard gun or a Spoolmatic® gun on Millermatic® 210, 251 and 350 without flipping a switch. The machine senses the gun you are using when you pull the trigger.
Hadfield Steel is another name sometimes used for austenitic manganese steel derived from its inventor.
Hafnium is the metal used most commonly for the electrode emitter for air or oxygen plasma gases.
Hand Shield is a protective device for shielding the eyes, face, and neck in arc welding. A hand shield is equipped with a suitable filter plate and is designed to be held by the hand.
Hard Facing is a form of surfacing in which a coating or cladding is applied to a substrate with the purpose of reducing wear or loss of material by abrasion, impact, erosion, galling, and cavitation.
Hardenable Steel is an alloy of iron that is subject to hardening when rapidly cooled.
Hardening is an operation of quenching steels from the austenitic temperature range for producing martensite or a hard structure.
Harsh is a reference to the welding arc as spattering, noisy and erratic.
Heat Affected Zone is an area of the base metal that did not become molten in the welding process but did undergo a microstructure change.
Heat Affected Zone is a portion of the base metal, adjacent to a weld, the structure or properties, altered by the heat of welding.
Heat-Shield is a device located on the very front of a mechanized torch. It provides electrical isolation from the nozzle during piercing and cutting operations.
Heat Treatment is any of the operations involving the heating and cooling of metals or alloys.
Helix of Continuous Welding Electrodes, when lying free on a smooth surface, it is a tendency of a length of the electrode to form a spiral.
Helmet (eye protection) is a protection device for shielding the eyes, face, and neck from UVs, and used in arc welding.
Hertz is often referred to as ‘cycles per second.’ In the USA, the frequency or directional change of alternating current is usually 60 hertz.
High Alloy Steels is the steels containing in excess of 10% alloy content. Stainless steel is a high alloy because it contains an excess of 10% chromium.
High Carbon Steel is the steel with carbon content usually below 1.3% carbon but may range from 1.0-2.0%.
High Frequency covers the entire frequency spectrum above 50,000 Hz. Mainly used in TIG welding for stabilization and arc ignition.
High-Frequency Discharge is a high voltage power supplied to the plasma torch. It breaks down the air gap between the electrode and nozzle in order to initiate the plasma stream.
High-Speed Nozzle Design operates between 60-110 psig depending upon the brand. It uses high pressure and divergence to produce 10-15% faster cutting speeds.
High-Speed Steel is special alloy steel used for high-speed cutting and turning tools e.g. lathe bits. Any tools made of it can remove metal much faster than tools of ordinary steel.
High Strength Cast Iron is cast gray iron with a tensile strength in excess of 30,000psi (206,900kN/M²).
High Sulfur Steel is the steel with sulfur content ranging from 0.12-0.33%. It exhibits free-cutting properties and made for screw machine products.
Horizontal Fixed Position (pipe welding) is the position of a pipe joint in pipe welding where the axis of the pipe is approximately horizontal, and the pipe is not rotated during welding.
Horizontal Rolled Position (pipe welding) is the position of a pipe joint in pipe welding where the axis of the pipe is approximately horizontal, and welding is performed in the flat position by rotating the pipe.
Horizontal Welding Position is the welding position where the weld face lies in an approximately vertical plane and the weld axis at the point of welding is approximately horizontal.
Hot Crack is also known as ‘auto crack’, resulting from stress concentration in the relatively thin weld metal. Both the root cracks and crater cracks are forms of hot cracking.
Hot Quenching is the cooling of heated metals or alloys in a bath of molten metal or salt, instead of using water or oil cooling medium.
Hot Short is a metal that is brittle and unworkable above room temperature. The presence of sulfur in steel causes a hot short condition.
Hot Start is a hot start that provides a temporary increase in the output current during the start of a weld. It helps to ignite the arc quickly, provides excellent arc ignition without the electrode sticking and avoids any metallurgical default in the weld.
Hot Start™ is a Miller Technology Exclusive, used on some stick (SMAW) machines to make it easier to start difficult-to-start electrodes. It is used for arc starting only.
Impact Test is a measurement of the amount of energy required to rupture metals with sudden or shock loads.
Inadequate Joint Penetration is a joint penetration which is less than that specified.
Inclusion is an entrapped foreign solid material e.g. slag, flux, tungsten, or oxide.
Incomplete Fusion is a weld discontinuity where fusion did not occur between weld metal and fusion faces or adjoining weld beads.
Incomplete Joint Penetration is a joint root condition in a groove weld where the weld metal does not extend through the joint thickness.
Indentation is a depression on the exterior surface or surfaces of the base metal in a spot, seam, or projection weld.
Induced Current or Induction is a phenomenon of causing an electrical current to flow through a conductor when that conductor is subjected to a varying magnetic field.
Inductance, in short, circuiting arc welding, it is a feature in welding power sources that are designed for short-circuiting arc welding to retard the rate of current rise each time the electrode touches the weld puddle.
Induction Heating is an induction heating process that heats an electrically conducting object (usually a metal) by electromagnetic induction, through heat generated in the object by eddy currents.
Inert Gas is a gas such as helium or argon that does not combine chemically with the base metal or filler metal.
Infrared Radiation is electromagnetic energy with wavelengths from 770 to 12000 nanometers.
Ingot is a casting of steel that is formed at the mill from the melt of ore, scrap limestone, coke, etc.
Insulator is a material with a tight electron bond, relatively few electrons such as wood, glass, ceramics and most plastics.
Intergranular Penetration is a penetration of a filler metal along the grain boundaries of base metal.
Intermittent Weld is a weld where the continuity is broken by recurring unwelded spaces.
Inter-pass Temperature is the lowest temperature of the deposited weld metal at the time the next pass is started when making multiple-pass welds.
Inverter a power source that increases the frequency of the incoming primary power, thus providing for a smaller size machine and improved electrical characteristics for welding.
Inverter Power Source is a high-performance plasma power source design. It takes advantage of advanced power semiconductor circuitry to reduce the size and weight of the transformer.
Jimmy Jammer is a semi-automatic welding system that is composed of a manipulator, weld oscillator, cross slide, positioner, and turning rolls.
Joined Buildup Sequence is an order where the weld beads of a multiple-pass weld are deposited with respect to the cross-section of the joint.
Joint is a junction of units (metals) or the edges of them which are to be joined or have been joined.
Joint Clearance is the distance between the faying surfaces of a joint.
Joint Design is a joint geometry together with the required dimensions of the welded joint.
Joint Efficiency is the ratio of the strength of a joint to the strength of the base metal.
Joint Geometry/Design is a shape and dimensions of a joint in cross-section prior to welding.
Joint Penetration is a minimum depth of a groove or flange weld which extends from its face into a joint, exclusive of reinforcement.
Joint Root is a portion of a joint to be welded where the members approach closes to each other.
Joint Type is a weld joint classification based on five basic joint configurations i.e. corner joint, edge joint, butt joint, lap joint, and T-joint
Joint Welding Procedure is the materials, detailed methods, and practices employed in the welding of a particular joint.
Kerf is the width of the cut produced during a cutting process.
Keyhole TIG is a high speed and full penetration GTAW welding technology. It offers enormous productivity, cost and quality advantages in stainless steel and corrosion-resistant materials.
Killed Steel is a steel that is sufficiently deoxidized during the melting cycle to prevent gases from evolving during the solidification period.
Kilogram (kg) is SI unit symbol. The kilogram is the base unit of mass in the International System of Units (SI). 1 Kilogram = 2.2 pounds, 1 pound = 0.453592 Kilograms.
Kilowatt is a unit equal to 1,000 watts.
KVA (Kilovolt-amperes) is the 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.
KW (Kilowatts) is the actual power of the welding power source. It is used by the power source when it is producing its rated output. Kilowatts are found by taking volts times amps divided by 1,000 and taking into account any power factor.
Lack of Fusion is a nonstandard term for incomplete fusion.
Lack of Penetration is a nonstandard term for incomplete joint penetration.
Lap Joint is a joint between two overlapping members in parallel planes.
Layer is a stratum of weld metal or surfacing material. It may consist of one or more weld beads laid side by side.
Leg of a Fillet Weld is a distance from the root of the joint to the toe of the fillet weld.
Level Wound is a spooled or coiled filler metal that has been wound in distinct layers such that adjacent turns touch.
Lift-Arc™ is a Miller Technology Exclusive that allows TIG Arc to start without high frequency. It starts the arc at any amperage without contaminating the weld with tungsten.
Lightly Coated Electrode is a filler metal electrode consisting of a metal wire with a light coating applied. It is primarily for stabilizing the arc.
Linear Discontinuity is a discontinuity with a length that is substantially greater than its width.
Linear Indication is a test result in which a discontinuity in the material being tested is displayed as a linear or aligned array.
Liquidus is the lowest temperature at which a metal or an alloy is completely liquid.
Local Preheating is a specific portion of a structure.
Local Stress Relief Heat Treatment is a process of stress relief heat treatment of a specific portion of a structure.
Longitudinal Bend Test is a test in which a specimen is bent to a specified bend radius.
Longitudinal Crack is a crack with its major axis orientation approximately parallel to the weld axis
Longitudinal Sequence is an order in which the increments of a continuous weld are deposited with respect to its length.
Low Alloy Steels is the steels containing small amounts of alloying elements (usually 1½% to 5% total alloy content) and improving properties.
Low Carbon Electrodes is a non-filler metal electrode which is used in arc welding and cutting. It consists of a carbon or graphite rod, that may be coated with copper or other materials.
Low Fume Pulse™ is a technology developed by Lincoln Electric. It simplifies the balancing act between weld-fume control and weld floor productivity.
Low Hydrogen Electrodes are the stick electrodes with coating ingredients that are very low in hydrogen content. The low hydrogen level is kept by keeping the moisture content of the coating to a bare minimum.
Low OCV Stick™ reduces OCV on several Maxstar® and Dynasty® models when the power source is not in use, eliminating the need for add-on voltage reducers.
LVC™ (Line Voltage Compensation) is a Miller Technology Exclusive that keeps the output of a power source constant, regardless of minor fluctuations in input power.
Machine Welding is welding with equipment that performs the welding operation under the constant observation and control of a welding operator.
Macroetch Test is a test in which a specimen is prepared with a fine finish, etched, and examined under low magnification.
Malleableizing is an annealing operation that is used in connection with the change of white cast iron to malleable cast iron.
Manual Arc Welding is welding with a coated electrode. The travel speed controlled by hands and the rate the electrode is fed into the arc.
Manual Welding is a welding operation that is performed and controlled by hand completely.
Martensite is a structure, made up of ultra-hard, needle-like crystals, resulting from the transformation of austenite at a temperature considerably below the usual range, achieved by rapid cooling.
Matrix is a principal with a continuous metallic constituent in which crystals or free atoms of other constituents are embedded. It works as a binder, holding the entire mass together.
Mechanized Welding pertains to the control of a process with equipment that requires manual adjustment of the equipment controls in response to visual observation of the operation. It is done with the torch, gun, wire guide assembly, or electrode holder held by a mechanical device.
Melt Through is a visible root reinforcement that is produced in a joint welded from one side.
Melting Range is a temperature range between the solidus and liquids.
Melting Rate is a weight or length of electrode melted in a unit of time.
Melt-thru is a complete joint penetration for a joint welded from one side.
Metal Active Gas (MAG) Welding is similar to Metal Inert Gas (MIG) Welding.
Metal-Cored Electrode is a composite filler metal electrode consisting of a metal tube or other hollow configuration containing alloying ingredients.
Metal Electrode is a fillet or non-filler metal electrode. It is used in arc welding or cutting consisting of a metal wire or rod.
Metal Inert Gas (MIG) Welding is an arc welding process in which coalescence is produced by heating with an arc between a continuous filler metal (consumable) electrode and the work. Shielding is obtained from an externally supplied gas or gas mixture.
Metallic Bond is a principal bond that holds metals together. It forms between the base metals and filler metals in all welding processes.
Metallurgically Similar Steels is a multiple steel composition with the same crystal structure such as austenite or ferrite.
Metallurgy is a science and technology of extracting metals from their ores, refining them, and preparing them for use.
Method is an orderly arrangement or set form of procedure to be used in the application of welding or allied processes.
Microprocessor is one or more integrated circuits that can be programmed with stored instructions to perform a variety of functions.
Microstructure is a structure that is visible only at high magnification, with the aid of a microscope after preparation, such as polishing or etching.
MIG Welding is a MIG is an acronym for Metal-Inert-Gas or GMAW or Gas Metal Arc Welding. It is an arc welding process that uses a spooled, continuously fed filler metal (consumable) electrode. Shielding is provided by externally supplied gas or gas mixtures.
Mild Steel is an alloy of mostly iron with low content of alloying elements such as carbon and manganese.
Mill Scale is an iron oxide (FeO) coating normally found on the surface of hot-rolled steels.
Missouri Mule (MM) Series is a turning roll manufactured by Pandjiris with a capacity range of 30,000 lbs to 180,000 lbs. or more. It is designed for heavy-duty use.
MMA (Manual Metal Arc) Welding is an arc-welding process in which coalescence is produced by heating with an arc between a covered metal (stick) electrode and the work. Shielding is obtained from the decomposition of the electrode covering.
Molten Weld Pool is the liquid state of a weld prior to solidification as weld metal.
Mottled Iron is a cast iron with a structure consisting of a mixture of free cementite, free graphite, and pearlite.
MTE is a Miller Technology Exclusive.
MVP™ (Multi-Voltage Plug) is the Miller Technology Exclusive that allows the connection of Millermatic® DVI™ or Passport™ to 115- or 230-volt receptacles without tools; just choose the plug that fits the receptacle.
Neutral Flame is an oxy/fuel gas flame with neither oxidizing nor reducing characteristics.
Neutral Fluxes are the neutral fluxes that produce little change to mechanical properties when adjusting the voltage.
Nondestructive Examination (NDE) is an act of determining the suitability of some material or component for its intended purpose by using the techniques that do not affect it serviceability
Non-Ferrous, it does not contain iron i.e. aluminum, copper and copper alloys, etc.
Non-transferred Arc is an arc between the electrode and the constricting nozzle of the plasma arc torch. And the workpiece is not in the electrical circuit.
Nozzle is a consumable torch part, containing a hole or orifice through which the arc passes and directs shielding media.
Nozzle Diameter is a diameter of the nozzle through which the plasma arc passes.
Off-Center refers to the coating being eccentric and thicker on one side of the electrode than the opposite side.
Ohm is a unit of electrical resistance to current flow.
Open Circuit Voltage is a voltage present at the electrode in the brief interval before the torch ignites. It is still active whenever the arc is extinguished with power.
Open-Circuit Voltage (OCV) is a difference in electrical potential between two terminals when no current is flowing in the welding circuit.
Orifice Diameter (nozzle diameter) is a diameter of the nozzle through which the plasma arc passes.
Orifice Gas (plasma gas or cutting gas) is a gas-directed into the torch to surround the electrode. It becomes ionized by the arc to form a plasma and issues from the torch nozzle as a plasma jet.
Out-of-Position Welds are the welds that are made in positions other than flat or horizontal fillets.
Overlap is the protrusion of weld metal beyond the toe, face, or root of the weld.
Oxy/Fuel Ratio is the relationship of a cubic foot of oxygen to the cubic foot of fuel gas mixture necessary to achieve maximum flame temperature. The ratio of it varies with fuel characteristics.
Oxygen Bore is an orifice in the cutting nozzle through which oxygen is directed at the plate for cutting. Oxygen Bore controls the amount of oxygen consumed during cutting.
Oxygen Factor is the fuel efficiency times the oxy/fuel ratio for a given fuel to determine the multiples of oxygen needed to duplicate the performance of acetylene. The acetylene oxygen factor is 1.5.
Pak is a rugged tubular steel frame enclosure that is designed to accommodate multiple power supplies for multi-operator welding systems.
Palm™ OS Compatibility, it replaces the need for data cards and remote-control pendants on Axcess models.
Partial Joint Penetration is a joint penetration that is less than complete.
Pass is a single progression of welding or surfacing operation along with a joint, weld deposit, or substrate. It results in a weld bead, layer, or spray deposit.
Pearlite is a eutectoid alloy of iron and 85% carbon consisting of layers or plates of ferrite and cementite.
Peel Test is a destructive method of inspection. It mechanically separates a lap joint by peeling.
Peening is a mechanical working of metals using impact blows. Peening is recommended for thicker sections.
Penetration is the depth below the surface of the base metal to which welding heat is enough for the metal to melt and become liquid or semi-liquid.
Phase Transformation is the changes in the crystalline structure of metals caused by temperature and time.
Piercing is a method of starting a plasma arc cut where the arc plunges into and through the workpiece before cutting begins.
Pig Iron is a product of the blast furnace cast into blocks convenient for handling or storage.
Pilot Arc is a low current arc between the electrode and the constricting nozzle of the plasma arc torch to ionize the gas.
Pilot Hole is a punched hole at (near) the plate edge of which the plasma arc cut is started.
Piper Series is the turning rolls manufactured by Pandjiris with a capacity range of 1,500 lbs. to 10,000 lbs: Mini Pipers, Piper 3, and Super Piper.
Plano Lens (eye protection) is a lens that does not incorporate correction.
Plasma is a gas that has been heated by an arc to at least a partially ionized condition, enabling it to conduct an electric current.
Plasma Arc Cutting (PAC) is an arc cutting process that uses a constricted arc and removes the molten metal in a high-velocity jet of ionized gas. Plasma arc cutting is a direct current electrode negative (DCEN) process.
Plasma Arc Gouging, it utilizes a plasma arc for metal removal. An electric arc contained inside a gas shield is passed through a constricting orifice in order to generate extremely high temperatures and a high-velocity stream of ionized gas.
Plasma Arc Welding (PAW) produces coalescence of metals by heating them with a constricted arc between an electrode and the workpiece (transferred arc) or the electrode and the constricting nozzle (non-transferred arc). Shielding is obtained from the hot, ionized gas issuing from the orifice.
Plasma Gas (orifice gas or cutting gas) – It is a gas that is directed into the torch to surround the electrode. It becomes ionized by the arc to form a plasma and issues from the torch nozzle as the plasma jet.
Plasticity is the ability of a metallic state to undergo permanent deformation without rupture.
Plug Weld is a circular weld made through a hole in one member of a lap or T-joint fusing.
Plunger, it is installed behind the removable seat in a plasma torch head to enable the safety interlock.
Polarity is the electrode welding polarity that affects the penetration level of the weld. With most arc welding processes, DC+ (direct current electrode positive) polarity produces more weld penetration, because more arc energy is focused into the base plate. Conversely, DC- (direct current electrode negative) polarity produces less weld penetration, because more arc energy is focused into the electrode and not into the base plate.
Porosity is a cavity-type discontinuity formed by gas entrapment during solidification.
Positioned Weld is a weld made in a joint that has been so placed as to facilitate making the weld.
Post Weld Heat Treatment is a reheating the weldment to 1100°F to 1350°F after welding and holding at that temperature for a specified length of time. It restores toughness in the heat-affected zone.
Post-heating, it is applied to the base metal after welding or cutting, for the purpose of tempering, stress-relieving, or annealing.
Postweld Heat Treatment is a heat treatment subsequent to welding.
Pounds Per Square Inch (psi) is a measurement equal to a mass or weight applied to one square inch of surface area.
Power Efficiency is that how well an electrical machine uses the incoming electrical power.
Power Factor Correction is normally used on single-phase, constant current power sources to reduce the amount of primary amperage demanded from the power company while welding.
Power Mode® is an enhanced MIG mode developed by Lincoln Electric. It can deliver excellent arc stability with reduced spatter at high travel speeds, resulting from an extended short arc range at higher wire feed speed procedures.
Power Source is an apparatus for supplying current and voltage suitable for welding, cutting, etc.
Precision Pulse™ is an enhanced MIG pulse mode by Lincoln Electric. It features a tight, focused arc for fast vertical up welding and outstanding out-of-position puddle control.
Preheat is the heating of the parts of a structure to be welded before welding is started. It is done to minimize thermal shock and of slowing the cooling rate.
Preheat Temperature is a specified temperature that the base metal must attain in the welding, brazing soldering, thermal spraying, or cutting area immediately before these operations are performed.
Preheating is the application of heat to the base metal immediately before welding, brazing, soldering, thermal spraying, or cutting.
Primary Power, it is often referred to as the input line voltage and amperage available to the welding machine from the shop’s main power line. Its primary input power is AC and may be single-phase or three-phase.
Prime Power Generator Rating is a power rating that can be defined as having an ‘unlimited run time’.
Procedure is the detailed elements of a process or method used to produce a specific result.
Procedure Qualification is a demonstration that welds made by a specific procedure can meet prescribed standards.
Progressive Block Sequence is a sequence during which successive blocks are completed progressively along the joint.
Protective Atmosphere is a gas envelope that surrounding the part to be brazed, welded or thermally sprayed, with the gas composition controlled with respect to chemical composition, dew point, pressure, flow rate, etc.
Proton is a positively charged particles which are part of the nucleus of atoms.
Pulse is a current of controlled duration through a welding circuit.
Pulse Time is the duration of a pulse.
Pulse Transfer is the mode of metal transfer somewhat between spray and short-circuiting.
Pulsed MIG (MIG-P), it is a modified spray transfer process that produces no spatter because the wire does not touch the weld puddle.
Pulsed MIG Welding is a process that is used mainly for welding aluminum and stainless steel. The method of controlling the transfer of the droplets by current pulses from the power source makes it possible to extend the spray range down.
Pulsed Power Welding is an arc welding method where the power is cyclically programmed to pulse.
Pulsed Spray Welding is an arc welding method where the current in pulsed to utilize the advantages of the spray mode of metal transfer at average currents equal to or less than the globular to spray transition current.
Pulsed TIG (TIG-P), it is a modified TIG process appropriate for welding thinner materials.
Pulse-on-Pulse®, it is an arc modulation MIG pulse mode by Lincoln Electric that can deliver a TIG (GTAW)-like bead appearance.
Pulsing is sequencing and controlling the amount of current, the frequency and the duration of the welding arc.
Push Angle is a travel angle when the electrode is pointing in the direction of travel. It defines the position of high energy beams, welding rods, welding guns, welding torches, thermal cutting and thermal spraying torches, and thermal spraying guns in a forward direction.
Quench/Quenching is the process of fast-cooling metals or alloys i.e. steel in the process of hardening, oil quenching, water quenching, as air quenching, etc.
Radial Crack is a crack which originates in the fusion zone and extends into the base metal, usually at right angles to the line of fusion. This happens due to the high stress involved in the cooling of a rigid structure.
Radiographic Quality is the soundness of a weld that shows no internal or under-bead cracks, voids or inclusions when inspected by X-ray or gamma-ray techniques.
Rapid X™ is a premium MIG pulse mode by Lincoln Electric. It is designed to deliver higher travel speeds and extremely low spatter levels.
Rapid Z™ is a Lincoln Electric process for increasing stability and travel speeds while reducing spatter and internal porosity on Zinc coated materials.
RapidArc® is a Lincoln Electric exclusive and accelerates MIG pulse mode with a short arc length compared to pulse and CV-spray for high travel speed applications.
Rated Load is an amperage and voltage the power source that is designed to produce for a given specific duty cycle period.
Reaction Stress is residual stress which could not otherwise exist if the members or parts being welded were isolated as free bodies without connection to other parts of the structure.
Reactor (arc welding) is a device used in arc welding circuits for the purpose of minimizing irregularities in the flow of welding current.
Rectifier is an electrical device that is used to change alternating current to direct current.
Reduced Section Tension Test is a test in which a transverse section of the weld is in the center of the reduced section of the specimen.
Regulated Metal Deposition (RMD) (modified short-circuit MIG) is an advanced welding process developed by Miller Electric. Precisely, it controls short-circuit transfer technology that improves welding quality and productivity on stainless steel pipe.
Reinforcement of Weld is a weld metal in excess of the quantity required to fill a joint.
Residual Stress is stress remaining in a structure or member as a result of thermal or mechanical treatment or both.
Residual Stresses are the internal stresses that exist in metal at room temperature. It occurs due to previous non-uniform heating and expansion, a composite structure composed of a ductile constituent and a brittle one.
Resistance Spot Welding (RSW) is a process (no arc with this process) where two pieces of metal are joined by passing current between electrodes positioned on opposite sides of the pieces to be welded.
Reverse Polarity is the arrangement of direct current arc welding leads with the work as the negative pole and the electrode as the positive pole of the welding arc.
RMS (Root Mean Square), it is the “effective” values of measured AC voltage or amperage. RMS equals 0.707 times the maximum or peak value.
Root is the narrowest point in the gap between two members to be welded. These points are usually one and the same.
Root Bend Test is a test where the weld root is on the convex surface of a specified bend radius.
Root Crack is a crack in the weld or heat-affected zone occurring at the root of a weld.
Root Face is a portion of the groove face adjacent to the root of the joint.
Root of Joint is a portion of a joint to be welded where the members approach closest to each other. It may be either a point, a line or an area in cross-section the root of the joint.
Root of Weld is the points, as shown in cross-section, at which the back of the weld intersects the base metal surfaces.
Root Opening is a separation or intentional gap between the members to be joined at the root of the joint.
Root Pass is an initial weld bead deposited in a multi-pass weld requiring high weld integrity.
Root Penetration is a depth that a weld extends into the root of a joint measured on the centerline of the root cross-section.
Root Radius is a nonstandard term for groove radius.
Root Reinforcement is a welded reinforcement opposite the side from which welding was done.
Root Surface is an exposed surface of a weld on the side other than that from which welding was done.
Rutile is a natural form of the mineral titanium dioxide (TiO2).
SAE stands for Society of Automotive Engineers.
Scarf Joint is a form of the butt joint.
SCR Power Source is a type of power source that uses a semiconductor device known as the silicon-controlled rectifier in the main power circuit.
Scratch Start TIG is a common method of striking an arc in the TIG welding process. It involves dragging the tungsten electrode across the surface of the metal.
Seal Weld is a weld that is designed primarily to provide a specific degree of tightness against leakage.
Seam Weld is a continuous weld that is made between or upon overlapping members. The coalescence may start and occur on the faying surfaces or may have proceeded from the surface of one member.
Seam Welding is the making of seam welds.
Secondary Circuit is a portion of a welding machine that conducts the secondary current between the secondary terminals of the welding transformer and the electrodes, or electrode and work.
Secondary Gas is unlike the plasma gas (secondary gas or shielding gas) that does not pass through the orifice of the nozzle. It passes around the nozzle and forms a shield around the arc.
Selective Block Sequence is a block sequence where successive blocks are completed in a certain order.
Self-Hardening Steels are steels that become martensitic or fully hard by air cooling from above their critical temperature or from the austenitizing temperature.
Self-Shielded Flux Cored Arc Welding (FCAW-S) is a flux-cored arc welding process variation where the shielding gas is obtained exclusively from the flux within the electrode
Semi-automatic Arc Welding is an arc welding with equipment that controls only the filler metal feed.
Semi-Automatic Welding is welding with a continuous solid wire or flux Cored electrode in which the wire feed speed, shielding gas flow rate, and voltage are pre-set on the equipment.
Semi-blind Joint is a joint in which one extremity of the joint is not visible.
Series Submerged Arc Welding (SAW-S) is a submerged arc welding process variation where the electric current is established between two (consumable) electrodes. The work is not in the electrical circuit.
SharpArc® is a Miller Technology Exclusive that optimizes the size and shape of the arc cone, bead width and appearance, and puddle fluidity. Available on the Millermatic® 350/350P.
Shear is a force that causes deformation or fracture of a member by sliding one section against another in a plane or planes.
Shield/Shielding Gas is unlike the plasma gas (secondary gas) that does not pass through the orifice of the nozzle. It passes around the nozzle and forms a shield around the arc.
Shielded Carbon Arc Welding (SCAW) is a carbon arc welding process variation that produces coalescence of metals by heating them with an electric arc between a carbon electrode and the work. Shielding is obtained from the combustion of a solid material fed into the arc.
Shielded Metal Arc Welding (SMAW) is an arc welding process producing coalescence of metals by heating them with an arc between a covered metal electrode and the work.
Shielding Gas is a protective gas used to prevent atmospheric contamination.
Short Circuit Gas Metal Arc Welding (GMAW-S) is a gas metal arc welding process variation in which the consumable electrode is deposited during repeated short circuits.
Short-Circuiting Transfer is a mode of metal transfer in gas metal arc welding at low voltage and amperage. It takes place each time the electrode touches or short-circuits to the weld puddle, extinguishing the arc.
Short-Circuiting Transfer (gas metal arc welding) is a type of metal where melted material from a consumable electrode which is deposited during repeated short circuits.
Shrinkage Void is a cavity-type discontinuity normally formed by shrinkage during solidification.
Sieve Analysis is a method of determining particle size distribution. It is usually expressed as the weight percentage retained upon each of a series of standard screens of decreasing mesh size.
Single-phase Circuit is an electrical circuit producing only one alternating cycle within a 360-degree time span.
Single-welded Joint is any joint that welded from one side only in arc and gas welding.
Skull is a un-melted residue from a liquated filler metal.
Slag is the brittle mass that forms over the weld bead on welds made with coated electrodes, flux-cored electrodes, submerged arc welding and other slag producing welding processes.
Slag Follow refers to how the slag follows the puddle. If the slag is close, it crowds the puddle, making it more difficult for the welder to observe the arc. On the other hand, if the slag follows fast, it allows for faster travel speeds.
Slag Inclusion is a nonmetallic solid material that is entrapped in weld metal or between weld metal and base metal.
Slope or Slope Control is a necessary feature in welding power sources that are used for short-circuiting arc welding.
Slot Weld is a weld made in an elongated hole in one member of a lap or T-joint joining. The hole may be open at one end and maybe partially or filled with weld metal.
Slugging is an act of adding a separate piece or pieces of material in a joint before or during welding. It results in a welded joint not complying with design, drawing, or specification requirements.
Smart Fuel Tank is the design of the tank that minimizes the chance of fuel backflow.
Smooth is an arc transfer that is very consistent.
Solidus is the highest temperature at which a metal or alloy is completely solid.
Spacer Strip is a metal strip or bar prepared for a groove weld and inserted in the root of a joint to serve as a backing and to maintain root opening during welding.
Spalling is the loss of particles or pieces from a surface due to cracking.
Spark Test is a test used to identify a metal by bringing it into contact with a power-driven, high-speed grinding wheel which produces spark patterns.
Spatter happens when the metal particles are expelled during welding and which do not form a part of the weld.
Spatter Loss is a metal lost due to spatter.
Spiral Arc Welding (SAW) is an arc welding process/procedure used in the pipe industry.
Spool is a type of filler metal package consisting of a continuous length of electrode wound on a cylinder flanged at both ends.
Spool Gun consists of a gun with a pistol grip and a 4-inch diameter wire spool mounted on the back end for providing mobility. There are two classes of spool guns, one works with both CC or CV power sources and other works with only CV power sources.
Spot Weld is a weld made between or upon overlapping members where coalescence may start and occur on the faying surfaces or may proceed from the surface of one member.
Spot Welding is a resistance welding method that is commonly used to join thin sheet materials by overlapping joints.
Spray Arc Transfer is a mode of metal transfer across the arc where the molten metal droplets are smaller than the electrode diameter.
Spray Arc Welding is a process where molten material is transferred in the form of many small droplets.
Square-groove Weld is a type of groove weld.
Squarewave™ is the AC output of a power source that can rapidly switch between the positive and negative half cycles of alternating current.
Stabilized Stainless Steel is high-chromium steel which does not lose its chromium from solid solution by precipitation.
Staggered Intermittent Fillet Welding is the two lines of intermittent fillet welding on a joint in which the fillet weld increments is one line are staggered with respect to those in the other line.
Standby Power Generator Rating is the standby power generators that are most often used in emergency situations, such as during a power outage.
Standoff Distance is a distance between the outermost portion of the torch and the work surface.
Standoff Guide is used with the plasma torches to drag cut. It maintains a fixed distance from the torch tip to the workpiece.
Steel is an alloy of iron with up to 1.4% carbon, usually less.
Stick Welding SMAW (Shielded Metal Arc Welding) is a welding process in which an electric arc is created between a coated consumable electrode and the workpiece to be welded. It results in the parent material to be fused together and the electrode to melt.
Stick-out is a length of unmelted electrode extending beyond the end of the gas nozzle.
Stitch Welding is the use of intermittent welds to join two or more parts.
Straight Polarity is the arrangement of direct current arc welding leads where work is the positive pole and the electrode is the negative pole of the welding arc.
Strain is the physical effect of stress, which is usually evidenced by stretching or other deformation of the material.
Stranded Electrode is a composite filler metal electrode. It consists of stranded wires that may mechanically enclose materials to improve properties, stabilize the arc or provide shielding.
Stress is the load or amount of a force that is applied to a material, tending to deform or break it.
Stress Corrosion Cracking is a failure of metals by cracking under the combined action of corrosion and stress, residual or applied.
Stress Relief Cracking is an intergranular cracking in the heat-affected zone of weld metal. It occurs during the exposure of weldments to elevated temperatures during post-weld heat treatment or high-temperature service.
Stress Relief Heat Treatment is uniform heating of a structure or a portion thereof to a sufficient temperature to relieve the major portion of the residual stresses, followed by uniform cooling.
Stress Relieved is a reheating of a weldment to a temperature below the transformation temperature and holding it for a specified period.
Stringer Bead is a type of weld bead made without appreciable weaving motion.
Stub is a short length of filler metal electrode, welding rod, or brazing rod that remains after its use for welding or brazing.
Stud Welding is a process for attaching a fastener, bolt or nut to a metal base. Fasteners are usually threaded, unthreaded or tapped variety.
Submerged Arc Welding (SAW) is a welding process that uses the heat produced by an electric arc between a bare metal electrode and the work. And the shielding is supplied by a layer of granular, fusible flux material blanketing the arc.
Substrate is the base material to which a thermal sprayed coating or surfacing weld is applied.
Sun Vision™ is a Miller Technology Exclusive that allows easy reading of digital meters in direct sunlight or shade on Trailblazer® 275 DC and 302.
SureStart™ is a Miller Technology Exclusive that provides consistent Axcess® arc starts by precisely controlling power levels for specific wire and gas combinations.
Surface Preparation is the operations that are necessary to produce a desired or specified surface condition.
Surface Tension Transfer (STT) is an advanced waveform MIG welding process developed by Lincoln Electric. It uses high-frequency inverter technology with advanced waveform control to produce a high-quality weld.
Surfacing is a deposition of filler metal (material) on a base metal (substrate) to obtain desired properties or dimensions.
Surfacing Weld is a type of weld composed of one or more stringer or weave beads deposited on an unbroken surface to obtain desired properties or dimensions.
Swirl Baffle serves a mounting platform for the nozzle, sets up a swirling direction of the gas through the small holes in the swirl baffle and carries the electrical current to the workpiece.
Synchronized Tandem MIG® is a Lincoln Electric technology that overcomes the deposition rate limitations of a single wire by using two wires and specific waveforms.
Syncro Start™ is a Miller Technology Exclusive that allows selectable customized arc starts on Syncrowave® 200, 250 DX and 350 LX.
Tack weld is a weld that is made to hold parts of a weldment in proper alignment until the final welds are made.
Tanker Series are the turning rolls manufactured by Pandjiris with a capacity range of 8,000 to 15,000 lbs.: Tanker 80/40 and Tanker 150/75. It is designed to handle a wide range of diameter sizes.
Taps are the connections to a transformer winding which are used to vary the transformer turns ratio, thereby controlling welding voltage and current.
Temper is the amount of carbon present in the steel: 10 temper is 1.00% carbon. And the degree of hardness that an alloy has after heat treatment or cold working, via the aluminum alloys.
Temper of Continuous Welding Electrodes is the stiffness or strength of the electrode.
Temporary Weld is a weld made to attach a piece or pieces to a weldment for temporary use in handling, shipping, or working on the weldment.
Tensile Strength is a resistance of a material to a force that is acting to pull it apart.
Tension Test is a test in which a specimen is loaded in tension until the failure occurs.
Theoretical Throat is the distance from the beginning of the root of the joint perpendicular to the hypotenuse of the largest right triangle.
Thermal Stresses is the stresses in metal resulting from non-uniform temperature distribution.
Thoriated Tungsten is a metal that is used as the plasma cutting electrode emitter for a non-oxidizing plasma gas such as nitrogen.
Three-Phase Circuit is an electrical circuit delivering three cycles within a 360-degree time span, and the cycles are 120 electrical degrees apart.
Throat is the cylindrical part of the orifice that controls the quantity of oxygen that is consumed.
TIG (Tungsten Inert Gas) Welding is an arc welding process where the coalescence is produced by heating with an arc between a single tungsten (non-consumable) electrode and the work Shielding is obtained from a gas or gas mixture.
TIG Welding (GTAW) is a process that welds using the heat of a non-consumable tungsten electrode. The filler metal can be used, and argon inert gas or inert gas mixtures are used for shielding.
Tight refers to the removal of slag, tight means it does not release readily and will require moderate chipping to remove.
Tip Saver Short Circuit Protection™ is a Miller Technology Exclusive that shuts down output when the MIG contact tip is shorted to the work, on the Millermatic® 135 and 175.
Tip to Work Distance is a distance between the outermost portion of the contact tube or tip and the work surface.
Titania is a synthetic form of titanium dioxide (TiO2).
T-Joint is a joint between two members located approximately at right angles to each other in the form of a T.
Toe is a point on the weld bead that meets the parent metal. Every weld bead has two “toes”.
Toe Crack is a crack in the base metal occurring at the toe of a weld. It may be a radial or stress crack.
Toe of Weld is a junction between the face of a weld and the base metal.
Ton is a unit of weight that is equal to 2000 pounds in the United States and 2240 pounds in Britain.
Tonne is called a metric ton in the United States to help differentiate between metric and imperial. 1 tonne = 1,000 kilogram = 2,200 pounds
Torch is a device used in the TIG (GTAW) process to control the position of the electrode, to transfer current to the arc.
Torch Detection™ is a Miller Technology Exclusive. Syncrowave® 250 DX and 350 LX detect if TIG torch is water – or air-cooled.
Torch Standoff Distance is a distance between a nozzle and a workpiece.
Torch to Work Distance is a distance between the outermost portion of the torch and the work surface.
Touch Start is a procedure to initiate an arc for TIG (GTAW). The tungsten is touched against the workpiece and then lifted, establishing an arc.
Transferred Arc is a plasma arc that is established between the electrode of the plasma arc torch and the workpiece.
Transformation is the changes in the crystalline structure of metals caused by temperature and time.
Transformation Temperature is a temperature (usually 1600°F) at which the crystal structure of the steel changes,
Transformer is an electrical device used to raise or lower the voltage and inversely change the amperage.
Transition Temperature is a temperature (range of 1500-1600°F) at which the crystal structure of steel changes.
Transverse Crack is a crack with its major axis oriented approximately perpendicular to the weld axis.
Transverse Weld Test Specimen is a weld test specimen with its major axis perpendicular to the weld axis.
Travel Angle is an angle less than 90 degrees between the electrode axis and a line perpendicular to the weld axis, in a plane determined by the electrode axis and the weld axis.
Travel Angle (electrode) is an angle that the electrode makes with a reference line perpendicular to the axis of the weld in the plane of the weld axis.
Travel Angle (pipe) is an angle that the electrode makes with a reference line extending from the center of the pipe through the puddle in the plane of the weld axis.
Travel Angle of Welding Electrode is the degree of the travel angle, whether a push or drag travel angle. A travel angle of 0° to 10° will result in more weld penetration.
Tri-Cor™ Technology is a Miller Technology Exclusive that stabilizes design on the Bobcat™ 250 that delivers smoother welds. It decreases spatter with E7018 electrodes, without sacrificing performance with E6010 electrodes.
Trigger Reset permits quick reset at a gun rather than a machine.
Trimix or Triple Mix is a shielding gas consisting of approximately 90% helium, 7-1/2% argon, and 2-1/2% carbon dioxide used primarily for short-circuiting arc welding of stainless steels.
Tungsten is a rare metallic element with an extremely high melting point (3410° Celsius). It is used in the manufacturing of TIG electrodes.
Tungsten Electrode is a non-filler metal electrode that is used in arc welding or cutting, made principally of tungsten.
Ultimate Tensile Strength is the maximum pulling force to which the material can be subjected without failure.
Ultraviolet Light is a short wavelength light emitted during arc cutting and welding processes. It is harmful to the eyes and skin.
Under-bead Crack/Cracking is a crack in the heat-affected zone generally not extending to the surface of the base metal. Sometimes, it is referred to as cold cracking.
Undercut is a groove that is melted into the base metal adjacent to the toe or root of a weld and left unfilled by weld metal.
Underfill is a depression on the face of the weld or root surface that is extending below the surface of the adjacent base metal.
Uphill is welding with an upward progression.
Upslope Time is a time during which the welding current continuously increases from the beginning of welding current.
Vertical Position is a position of welding where the axis of the weld is approximately vertical.
Vertical Position (pipe welding) is a position of a pipe joint where the welding is performed in the horizontal position and the pipe may or may not be rotated.
V-Groove Weld is a type of groove weld.
Volt is a unit of electromotive force or electrical pressure that causes current to flow in an electrical circuit.
Voltage is a potential difference in charge between two points. It acts as a force pushing electrons through a conductor.
Voltage Regulator is an automatic electrical control device. It is for maintaining a constant voltage supply to the primary of a welding transformer.
Voltage Sensing Wire Feeders is a voltage sensing wire feeder and operates on arc voltage, eliminating the need for a control cord between the power source and the wire feeder. It can be paired with either a constant voltage (CV) or a constant current (CC) power source.
Volt-Amp Curve is a graph that shows the output characteristics of a welding power source. It shows the voltage and amperage capabilities of a specific machine.
Vortex is an intense swirling gas similar to a tornado. During cutting, most plasma arc cutting systems develop a vortex of some extent in the nozzle.
Wandering Sequence is a longitudinal sequence where the weld bead increments are deposited at random.
Watt is a unit of electrical power. Watts = Volts x Amperes
WaveWriter™ File Management is a Miller Technology Exclusive. It includes all Axcess™ file management functions, plus a simple, graphical wave-shaping program for the most demanding pulsed MIG applications.
Weathering Steel is a low alloy steel that is specially formulated to form a thin tightly adhering layer of rust. The copper and chromium are the main alloys of steel.
Weave Bead is a type of weld bead that is made with transverse oscillation.
Weld/Welding is a localized coalescence of metals or nonmetals produced either by heating the materials to the welding temperature, with or without the application of pressure or by the application of pressure alone and with or without the use of filler material.
Weld at Idle™ allows PipePro™ 304 to automatically weld at a quieter, lower RPM, using less fuel.
Weld Bead is a weld deposit resulting from a pass.
Weld Crack is a crack located in the weld metal or heat affected zone.
Weld Face is an exposed surface of a weld on the side from which welding was done.
Weld Gage is a device that is designed for checking the shape and size of welds.
Weld Metal is the portion of a fusion weld that has been melted during welding.
Weld Metal Area is an area of the weld metal as measured on the cross-section of a weld.
Weld Pass is the single progression of welding along a joint.
Weld Pool is a localized volume of molten metal in a weld prior to its solidification as weld metal.
Weld Puddle is a non-standard term for the weld pool.
Weld Reinforcement is a weld metal in excess of the quantity required to fill a joint.
Weld Transfer is a method by which metal is transferred from the wire to the molten puddle.
Weldability is a capacity of a material to be welded under the fabrication conditions.
Welder is a person who performs a manual or semiautomatic welding operation.
Welder Certification is a written verification certificate that a welder has produced welds meeting a prescribed standard of welder performance.
Welder Performance Qualification is a demonstration of a welder’s ability to produce welds meeting prescribed standards.
Welder Registration is an act of registering a welder certification or a photostatic copy thereof.
Welding is a material-joining process that is used in making welds.
Welding Arc is a controlled electrical discharge between the electrode and the workpiece.
Welding Current is current in the welding circuit during the making of a weld.
Welding Cycle is a complete series of events that are involved in the making of a weld.
Welding Electrode Classifications is an electrode numbering system of the American Welding Society (AWS) which provides detailed information on stick electrodes.
Welding Filler Metal is a metal or alloy to be added in making a weld joint that alloys with the base metal to form weld metal in fusion welded joints.
Welding Generator is a generator that is used for supplying current for welding.
Welding Head is a part of a welding machine or automatic welding equipment in which a welding gun or torch is incorporated.
Welding Leads is a work lead and electrode lead of an arc welding circuit.
Welding Machine is an equipment that is used to perform the welding operation.
Welding Operator is the person who operates a machine or automatic welding equipment.
Welding Power Source is an apparatus for supplying current and voltage suitable for welding
Welding Procedure is detailed methods and practices involving in the production of a weldment
Welding Process is the materials joining process that produces coalescence of materials by heating them to suitable temperatures, with or without the application of pressure or by the application of pressure alone, and with or without the use of filler metal.
Welding Rectifier is a device in a welding machine for converting alternating current to direct current.
Welding Rod is a form of filler metal that is used for welding or brazing which does not conduct the electrical current.
Welding Sequence is an order of making the welds in a weldment.
Welding Symbol is a graphical representation of a weld
Welding Technique is the details of a welding procedure that is controlled by the welder or welding operator.
Welding Wire is a form of welding filler metal, normally packaged as coils or spools. It may or may not conduct electrical current depending upon the welding process with which it is used.
Weldment is an assembly whose component parts are joined by welding.
Wet-Stacking is unburned fuel and engine oil collecting in the exhaust stack of a diesel engine. It is characterized by the exhaust stack being coated with a black, sticky, oily substance.
Wetting is bonding or spreading of liquid filler metal or flux on a solid base metal.
Wind Tunnel Technology™ is a Miller Technology Exclusive that protects electrical components and PC boards from contamination, significantly improving reliability.
Wire Feed Speed is a rate at which wire is consumed in arc cutting, thermal spraying, or welding.
Wire Straightener is a device that is used for controlling the cast of coiled wire to enable it to be easily fed into the gun.
Work Angle is an angle that the electrode makes with the referenced plane or surface of the base metal in a plane perpendicular to the axis of the weld.
Work Clamp is an assembly used to hold the workpiece, generally using hydraulic pressure for clamping force.
Work Connection is a connection of the work that lead to the work.
Work Hardening is a capacity of a material to harden as the result of cold rolling or another cold working.
Work Lead is an electric conductor between the source of arc welding current and the work.
Workpiece is a piece of material to be cut or gouged
Wrought Iron is a commercial form of iron that is tough, malleable, and relatively soft; less than 0.3% carbon.
X-RAY is a radiographic test method which is used to detect internal faults in a weld.
Yield Strength is a stress point at which permanent deformation results.
Zirconium is an element that is used in some electrodes as a plasma arc cutting electrode emitter.