Oxyfuel gas cutting (OFC) includes a group of cutting processes that use controlled chemical reactions to remove preheated metal by rapid oxidation in a stream of pure oxygen. This article discusses the operation principles and process capabilities of the OFC. It reviews the properties and compositions of fuel types such as acetylene, natural gas, propane, propylene, and methyl-acetylene-propadiene-stabilized gas. The article describes the effects of OFC on base metal, including carbon and low-alloy steels, cast irons, and stainless steels. It provides information on light cutting, medium cutting, heavy cutting, and stack cutting. The article informs that the basic oxyfuel method can be modified to allow gas cutting of metals, such as stainless steel and most nonferrous alloys, that resist continuous oxidation.

Oxyfuel gas cutting (OFC) includes a group of cutting processes that use controlled chemical reactions to remove preheated metal by rapid oxidation in a stream of pure oxygen. This article provides a detailed discussion on the principles of operation and the process capabilities of OFC. In addition to providing information on the equipment used, the article describes the properties of fuel gases (acetylene, natural gas). It also presents an overview of the effect of OFC on base metal and explains the application of OFC in cutting thin, medium, and thick sections, bars, and structural and close-tolerance shapes.

This article discusses the operating principles, types, and applications of shearing and slitting of different forms of steel, including plates, flat sheets, bars, coiled sheet and strips. In addition, it provides a detailed account of the cutting methods such as oxyfuel gas cutting, plasma arc cutting, oxygen arc cutting, laser beam cutting, and air carbon arc cutting and gouging, describing their process capabilities, equipment used, operating principles and parameters, and factors affecting their efficiency.

This article focuses on the mechanical and nonmechanical cutting methods used in metal fabrication industries. The most prevalent equipment used for mechanical cutting includes shears, iron workers, nibblers, and band saws. Nonmechanical methods of cutting include gas cutting, electric arc cutting, and laser cutting. The article concludes with information on the advantages of abrasive waterjet cutting, which is an alternative to laser cutting, gas cutting, and plasma cutting.

Electric arc cutting is used on ferrous and nonferrous metals for rough severing, such as removing risers or scrap cutting, as well as for more closely controlled operations. This article describes the operating principles, equipment selection, process variables, and safety measures recommended for plasma arc cutting and air carbon arc cutting. Special applications of electric arc cutting, including shape cutting, gouging, and underwater cutting, are also discussed. The article provides information on other electric arc cutting methods, namely, the exo-process and oxygen arc cutting. It concludes with information on the seldom-used electric arc cutting methods, such as shielded metal arc cutting, gas metal arc cutting, and gas tungsten arc cutting.

Safety is an important consideration in all welding, cutting, and related work. This article discusses the basic elements of safety general to all welding, cutting, and related processes. It includes safety procedures common to a variety of applications. The most important component of an effective safety and health program is management support and direction. The article reviews the role of management, training, housekeeping, and public demonstrations in welding safety to minimize personal injury and property damage. It provides information on the safety measures for eye and face protection in various welding and cutting operations. Injuries and fatalities from electric shock in welding and cutting operations can occur if proper precautionary measures are not followed. The article discusses the electrical safety aspects to be considered for various welding and cutting operations.

This article provides information on the various types of welds and joints. It reviews the weld joint design considerations: the ability to transfer load and the cost. The article explains the throat size and weld size requirements of fillet welds, and presents a comparison of fillet and groove welds. It details the various design considerations for groove-weld selection, including the groove angle, root opening, and depth of the groove. The article also describes the methods of edge preparation and concludes with an illustration of the recommended proportions of grooves for arc welding.

This article presents an overview of the rules, regulations, and techniques implemented to minimize the safety hazards associated with welding, cutting, and allied processes. Safety management, protection of the work area, process-specific safety considerations, and robotic and electrical safety are discussed. The article explains the use of personal protective equipment and provides information on protection against fumes, gases, and electromagnetic radiation. It concludes with a discussion on safe handling of compressed gases as well as the prevention and protection of fire and explosion.

Explosion welding (EXW) is a solid-state metal-joining process that uses explosive force to create an electron-sharing metallurgical bond between two metal components. This article discusses the process attributes of EXW, including metallurgical attributes, metal combinations, size limitations, configuration limitations, and bond zone morphology. It provides an overview of the common industrial applications and shop welding applications of EXW products. The article reviews different safety standards and regulations, such as noise and vibration abatement and process geometry. It concludes with a section on the EXW process sequence for welding a two-component flat plate product.

Plasma arc cutting (PAC) is an erosion process that utilizes a constricted arc in the form of a high-velocity jet of ionized gas to melt and sever metal in a narrow, localized area. This article discusses the process description, equipment, gases, operating sequence, process considerations, and applications of PAC. It concludes with a discussion on the safety measures associated with the PAC process.

Oxyfuel gas welding (OFW) is a manual process in which the metal surfaces to be joined are melted progressively by heat from a gas flame, with or without a filler metal. This article discusses the capabilities, advantages, and limitations of OFW. It describes the role of gases, such as oxygen, acetylene, hydrogen, natural gas, propane, and proprietary gases, in OFW. The article discusses the important elements of an OFW system, such as gas storage facilities, pressure regulators, hoses, torches, related safety devices, and accessories. It describes the sequence for setting up a positive-pressure welding outfit. The article provides information on forehand welding and backhand welding, as well as various joints used. It concludes with a discussion on repairs and alterations, as well as the safety aspects.

This article discusses the principles of operation, equipment needed, applications, and advantages and disadvantages of various fusion welding processes, namely, oxyfuel gas welding, electron beam welding, stud welding, laser beam welding, percussion welding, high-frequency welding, and thermite welding.

The use of thermal spray coatings to restore worn surfaces has provided a significant improvement in surface performance due to improved wear resistance. This article discusses the general use of thermal spray coatings in reducing predominant types of wear, namely, abrasive wear, erosive wear, adhesive wear, and surface fatigue.

This article overviews the classification of welding processes and the key process embodiments for joining by various fusion welding processes: fusion welding with chemical sources for heating; fusion welding with electrical energy sources, such as arc welding or resistance welding; and fusion welding with directed energy sources, such as laser welding, electron beam welding. The article reviews the different types of nonfusion welding processes, regardless of the particular energy source, which is usually mechanical but can be chemical, and related subprocesses of brazing and soldering.

This article introduces thermal spray coatings and describes the various types of coating processes and coating devices, including the flame spray, electric-arc spray, plasma spray, transferred plasma arc, high-velocity oxyfuel, and detonation gun. It provides information on the surface preparation methods and finishing treatments of coated parts. The article also explains the tests to evaluate the coating quality and the effects of coating structures and mechanical properties on coated parts. It concludes with a discussion on the uses of thermal spray coatings.

Repair and maintenance of parts and components is carried out as a logical procedure that ensures the production of a usable and safe component or it can be approached haphazardly. This article describes the requirements and repair techniques of arc and oxyfuel welding processes to repair weld defects and structural failures. It further discusses the preliminary assessment and base-metal preparation involved in weld repair. Furthermore, the article provides information on the general repair guidelines that are followed to ensure successful weld repairs of both ferrous (carbon steels, cast irons, and stainless steels) and nonferrous (titanium) base metals.

This article describes some examples of the different welding processes for gray, ductile, and malleable irons. These processes include fusion welding, repair welding, shielded metal arc welding, gas metal arc welding, flux cored arc welding, gas tungsten arc welding, submerged arc welding, oxyfuel welding, and braze welding. The article discusses various special techniques, such as groove-face grooving, studding, joint design modifications, and peening, for improving the strength of a weld or its fitness for service. The article describes other fusion welding methods such as electrical resistance welding and thermite welding. It reviews thermal spraying processes, such as flame spraying, arc spraying, and plasma spraying, of a cast iron.

Cast iron can be described as an alloy of predominantly iron, carbon, and silicon. This article discusses the classification of cast irons, such as gray cast iron, white cast iron, malleable cast iron, ductile cast iron, and compacted graphite iron. It reviews the various special techniques, such as groove face grooving, studding, joint design modifications, and peening, for improving the strength of a weld or its fitness for service. The article discusses the need for postweld heat treatment that depends on the condition of the casting, possible distortion during subsequent machining, the desired finish of the machined surfaces, and prior heat treatment. It describes various welding process for welding cast irons, including oxyfuel welding, braze welding, shielded metal arc welding, gas metal arc welding, and gas-tungsten arc welding.