WELDING GLOSSARY

LETTERS FROM A TO I INCLUDED

A
Air Carbon Arc Cutting (CAC-A) - A cutting process by which metals are melted by the heat of an arc using a carbon electrode. Molten metal is forced away from the cut by a blast of forced air. To remove large amounts of metal, look for a welder that can use carbons of at least 3/8 in diameter. Consumables: carbon electrodes, compressed air supply.
Alternating Current (AC) - An electrical current that reverses its direction at regular intervals, such as 60 cycles alternating current (AC), or 60 hertz.

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

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

Arc Force - Also called Dig and Arc Control. Gives a power source variable additional amperage during low voltage (short arc length) conditions while welding. Helps avoid "sticking" stick electrodes when a short arc length is used.

Automatic Welding - Uses equipment which welds without the constant adjusting of controls by the welder or operator. Equipment controls joint alignment by using an automatic sensing device.

C
Constant Current (CC) Welding Machine - These welding machines have limited maximum short circuit current. They have a negative volt-amp curve and are often referred to as “droopers”. The voltage will change with different arc lengths while only slightly varying the amperage, thus the name constant current or variable voltage.

Constant-Speed Wire Feeder - Feeder operates from 24 or 115 VAC supplied by the welding power source.

Constant Voltage (CV), Constant Potential (CP) Welding Machine – “Potential” and “voltage” are basically the same in meaning. This type of welding machine output maintains a relatively stable, consistent voltage regardless of the amperage output. It results in a relatively flat volt-amp curve as opposed to the drooping volt-amp curve of a typical Stick (SMAW) welding machine.

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

D
Defect - One or more discontinuities that cause a testing failure in a weld.

Direct Current (DC) - Flows in one direction and does not reverse its direction of flow as does alternating current.

Direct Current Electrode Negative (DCEN) - The specific direction of current flow through a welding circuit when the electrode lead is connected to the negative terminal and the work lead is connected to the positive terminal of a DC welding machine. Also called direct current, straight polarity (DCSP).

Direct Current Electrode Positive (DCEP) - The specific direction of current flow through a welding circuit when the electrode lead is connected to a positive terminal and the work lead is connected to a negative terminal to a DC welding machine. Also called direct current, reverse polarity (DCRP).

Duty Cycle - The amount of time a machine can be used at a particular output. Expressed as a percentage of a ten minute cycle, a 150 amp machine with a 30% duty cycle will allow 3 minutes of use for every ten and a 60% duty cycle would allow 6 minutes of use for every ten. The duty cycle increases as the power setting decreases so if 150 amp machine were to be used on a 30 amp setting the duty cycle might be 100% allowing it to be used 10 minutes out of every ten. Keep in mind, however, that the actual total time a machine can be used continuously is not determined by a timer, but typically by a thermostat within the machine which will shut it off if the machine is too hot and needs to cool down before it does more work. Therefore, even a 30% machine can be used more than ten minutes at a stretch.

F
Fixed Automation - Automated, electronically controlled welding system for simple, straight or circular welds.

Flexible Automation - Automated, robotically controlled welding system for complex shapes and applications where welding paths require torch-angle manipulation.

Flux Cored Arc Welding - An arc welding process which melts and joins metals by heating them with an arc between a continuous, consumable electrode wire and the work. Shielding is obtained from a flux contained within the electrode core. Depending upon the type of flux-cored wire, added shielding may or may not be provided from externally supplied gas or gas mixture. Consumables: contact tips, flux cored wire, shielding gas (if required, depends on wire type).

G
Ground Connection - A safety connection from a welding machine frame to the earth. Often used for grounding an engine-driven welding machine where a cable is connected from a ground stud on the welding machine to a metal stake placed in the ground.

Ground Lead - When referring to the connection from the welding machine to the work.

H
Hertz - Hertz is often referred to as "cycles per second". In the United States, the frequency or directional change of alternating current is usually 60 hertz.
High Frequency-Covers the entire frequency spectrum above 50,000 Hz. Used in TIG welding for arc ignition and stabilization.

I
Inert Gas - Used to shield the electric arc from outside contaminants and gases which may react with the weld. An inert chemical is one with a full outer shell of electrons which do not normally react with the other substances. Inert gases include argon and helium. Some other non-inert gases are used for welding such as CO2.

Input Voltage - The nominal number of volts required to power the equipment. 115V is what’s known as regular household current. 220V is what would normally be found in home garage, say to power a dryer.

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