Expansion And Contraction In Welding Operations

Most welding processes involve heat. High-temperature heat is responsible for much of the expansion and contraction in welding operations because warpage and stress occur. When metal is heated, it expands in all directions. When the metal cools, it contracts in all directions. Some distortions caused by weld shrinkage are shown in the figure above. There … Read more

Arc Welding

The term arc welding applies to a large and varied group of processes that use an electric arc as the source of heat to melt and join metals. In arc welding processes, the joining of metals, or weld, is produced by the extreme heat of an electric arc drawn between an electrode and the workpiece, or between … Read more

Welding And Weld Symbols

Welding cannot take its proper place as an engineering tool unless means are provided for conveying the information from the designer to the workmen. Welding symbols provide the means of placing complete welding information on drawings. The scheme for the symbolic representation of welds on engineering drawings used in this manual is consistent with the … Read more

Types Of Welds And Welded Joints

Welding is a material joining process used in making welds. A weld is a localized coalescence of metals or nonmetals produced either by heating the materials to a suitable temperate with or without the application of pressure or by the application of pressure alone, with or without the use of filler metal. Coalescence is a growing together or a growing … Read more

Other Arc Welding Equipment

Arc Welding Equipment: Cables Two welding cables of sufficient current-carrying capacity with heavy, tough, resilient rubber jackets are required. One of the cables should be composed of fine copper strands to permit as much flexibility as the size of the cable will allow. One end of the less flexible cable is attached to the ground lug … Read more

Welding Fire Hazards

a. Fire prevention and protection is the responsibility of welders, cutters, and supervisors. Approximately six percent of the fires in industrial plants are caused by cutting and welding which has been done primarily with portable equipment or in areas not specifically designated for such work. The elaboration of basic precautions to be taken for fire … Read more

Welding Print Reading

a. Drawings. Drawing or sketching is a universal language used to convey all necessary information to the individual who will fabricate or assemble an object. Prints are also used to illustrate how various equipment is operated, maintained, repaired, or lubricated. The original drawings for prints are made either by directly drawing or tracing a drawing on … Read more

Welding Process Abbreviations

Some commonly used welding process abbreviations are as follows: Abbreviation Process Name AHW Atomic Hydrogen Welding B Brazing (Capillary Action) BMAW Bare Metal Arc Welding BW Braze Welding (Groove or Fillet) CAC-A Carbon Arc Cutting (Also Gouging) CAW Carbon Arc Welding CAW-G Gas Carbon Arc Welding CAW-S Shielded Carbon Arc Welding CAW-T Twin Carbon Arc … Read more