Welding Terms Part-7 (N&O)

Dear Readers,

This is a continuation of Part 6. This article will be a valuable resource for anyone looking to enhance their knowledge of the Welding Works.

Neutral Flame – An oxy-fuel gas flame that is neither oxidizing nor reducing.

Nick Break Test – A method for testing the soundness of welds by nicking each end of the weld, then giving the test specimen a sharp hammer blow to break the weld from nick to nick. Visual inspection will show any weld defects.

Non-Destructive Testing – NDT involves the testing of welds without destroying the welds or parts.

Non-ferrous – Does not come from iron ore. It is mined pretty much in its true form such as copper, aluminum, nickel, etc.

Normalizing – Heating iron-base alloys to approximately 100 ºF (38 ºC) above the critical temperature range followed by cooling to below that range in still air at ordinary temperature.

Nugget – The fused metal zone of a resistance weld.

Nozzle – A brass attachment that is about three inches long and shaped as an open cylinder.

O2 – Oxygen.

OFW – Abbreviation for Oxy-fuel welding. There are three processes in the Oxy group including oxyacetylene, oxyhydrogen and pressure gas welding.

Open-Circuit Voltage – The voltage between the output terminals of the welding machine when no current is flowing in the welding circuit.

Orifice Gas – In plasma arc welding and cutting, the gas is directed into the torch to surround the electrode. It becomes ionized in the arc to form the plasma and issues from the orifice in the torch nozzle as the plasma jet.

Oscillate – Hand (welding holder) movement while dragging (back hand) or pushing (forehand) the weld Puddle.

Ovens – Used to remove dampness from the welding electrodes as moisture in the electrode adversely.

Overfill – Excess deposition of weld metal. Overfill is a waste of time and material and can weaken the steel by placing too much heat on the joint. (Opposite of this is Underfill)

Overhead Position – The position in which welding is performed from the underside of a joint and the face of the weld is approximately horizontal.

Overlap – The protrusion of weld metal beyond the toe, face, or root of the weld.

Oxidizing Flame – An oxy-fuel gas flame having an oxidizing effect (excess oxygen).

Oxyacetylene Cutting – An Oxygen cutting process in which the necessary cutting temperature is maintained by flames obtained from the combustion of acetylene with oxygen.

Oxyacetylene Welding – A welding process in which the required temperature is attained by flames obtained from the combustion of acetylene with oxygen.

Oxy-Arc Cutting – An Oxygen cutting process in which the necessary cutting temperature is maintained through an arc between an electrode and the base metal.

Oxy-City Gas Cutting – An oxygen cutting process in which the necessary cutting temperature is maintained by flames obtained from the combustion of city gas with oxygen.

Oxygen Cutting – A process of cutting ferrous metals by means of the chemical action of oxygen on elements in the base metal at elevated temperatures.

Oxygen Gouging – An application of oxygen cutting in which a chamfer or groove is formed.

Oxy-Hydrogen Cutting – An oxygen cutting process in which the necessary cutting temperature is maintained by flames obtained from the combustion of city gas with oxygen.

Oxy-Hydrogen Welding – A gas welding process in which the required welding temperature is attained by flames obtained from the combustion of hydrogen with oxygen.

Oxy-Natural Gas Cutting – An Oxygen cutting process in which the necessary cutting temperature is maintained by flames obtained by the combustion of natural gas with oxygen.

Oxy-Propane Cutting – An Oxygen cutting process in which the necessary cutting temperature is maintained by flames obtained from the combustion of propane with oxygen.