Welding Terms Part-4 (G&H)

Dear Readers,

This is continuation of Part-3. Welders can be found working in manufacturing plants, building job sites, and rebuilding infrastructure such as bridges and highways. Being able to move from industry to industry offers a higher level of job security than many other types of jobs. it’s useful to know some terms of Welding.

Galvanized – An electrochemical process where mild steel is hot-dipped into liquid zinc to make it anti-corrosive.

Gas Carbon-Arc Welding – An arc welding process in which fusion is produced by heating with an electric arc between a carbon electrode and the work. Shielding is obtained from an inert gas such as helium or argon. Pressure and/or filler metal may or may not be used.

Gas Metal Arc Welding (GMAW) – An arc welding process where the arc is between a continuous filler metal electrode and the weld pool. Shielding from an externally supplied gas source is required.

Gas Pocket – A weld cavity caused by the trapping of gases released by the metal when cooling.

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

Gas tungsten arc welding-pulsed arc (GTAW-P) – A variation of the gas tungsten arc welding process in which the current is pulsed.

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

Globular Transfer – A type of metal transfer in which molten filler metal is transferred across the arc in large droplets.

Goggles – Safety equipment worn to protect the welder’s eyes from harmful radiation while welding and cutting.

Gouging – The forming of a bevel or groove by material removal.

Groove – An opening or channel in the surface of a part or between two components which provides space to contain a weld.

Groove angle – The total included angle of the groove between parts to be joined by a groove weld.

Groove face – That surface of a member included in the groove.

Groove radius – The radius used to form the shape of a J- or U-groove weld joint.

Groove type – The geometric configuration of a groove.

Groove Weld – When a very strong weld is needed, such as where two columns are spliced together on a high-rise, it is important to get the maximum penetration and fusion. This is done by cutting a Bevel so that you can weld solid from the Root to the face of the parent metal. Examples: single V, single U, single J, double bevel etc.

Ground Connection – A safety connection from a welding machine frame to the earth. Nothing but earthing.

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

GTAW – Gas Tungsten Arc Welding. also known as tungsten inert gas (TIG) welding.

Guided Bend Test – A bending test in which the test specimen is bent to a definite shape by means of a jig.

Hammer Welding – A forge welding process.

Hand shield – Also called face Shield. A protective device, used in arc welding, for shielding the eyes, face and neck. A hand shield is equipped with a suitable filter plate and is designed to be held by the hand.

Hard Facing – A particular form of surfacing in which a coating or cladding is applied to a surface for the main purpose of reducing wear or loss of material by abrasion, impact, erosion, galling, and cavitation.

Hard Surfacing – The application of a hard, wear-resistant alloy to the surface of a softer metal.

Hardening – This term refers to a process used to increase the hardness of metal, typically iron-based alloys, by heating it above a certain critical temperature range and then rapidly cooling or “quenching” it.

Heat-Affected Zone (HAZ) – That section of the base metal, generally adjacent to the weld zone, whose mechanical properties or microstructure, have been altered by the heat of welding.

Heat Time – The duration of each current impulse in pulse welding.

Heat Treatment – An operation or combination of operations involving the heating and cooling of a metal or an alloy in the solid state for the purpose of obtaining certain desirable conditions or properties.

Helmet – protection equipment worn to protect the welder’s face and neck.

Hermetically Sealed – Airtight. Heterogenous – A mixture of phases such as: liquid-vapor or solid-liquid-vapor.

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.

Hold time – The time that pressure is maintained at the electrodes after the welding current has stopped.

Horizontal Weld – A bead or butt-welding process with its linear direction horizontal or inclined at an angle less than 45 degrees to the horizontal, and the parts welded being vertically or approximately vertically disposed.

Horn – The electrode holding arm of a resistance spot welding machine.

Horn Spacing – In a resistance welding machine, the unobstructed work clearance between horns or platens at right angles to the throat depth. This distance is measured with the horns parallel and horizontal at the end of the downstroke.

Hot Crack – A crack formed at temperatures near the completion of weld solidification.

Hot Pass – In pipe welding, the second pass which goes over the root pass.

Hot Short – A condition that occurs when a metal is heated to that point, prior to melting, where all strength is lost but the shape is still maintained.

Hydrogen Brazing – A method of furnace brazing in a hydrogen atmosphere.