Search Results for compressed gas cylinders

This article provides members of the thermal spray community with practical recommendations for the safe installation, operation, and maintenance of gas equipment used in the thermal spray process. It focuses on safety issues concerning gas equipment used in conjunction with thermal spray equipment at consumer sites. The article covers the gas sources (bulk or gaseous), the piping (hard and soft) leading to the gas console or the torch, and the specific safety devices used to help ensure safe operation. It discusses the characteristics and safety hazards of gases such as oxygen, compressed air, nitrogen, helium, argon, carbon dioxide, hydrogen, acetylene, kerosene, propylene, propane, and natural gas. The article also provides information on the maintenance and safety practices involved in the plumbing configurations of cylinder gas supply units and bulk gas supply units.

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.

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 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.

The gas tungsten arc welding (GTAW) process derives the heat for welding from an electric arc established between a tungsten electrode and the part to be welded. This article provides a discussion on the basic operation principles, advantages, disadvantages, limitations, and applications of the process. It describes the equipment used for GTAW, namely, power supplies, torch construction and electrodes, shielding gases, and filler metals as well as the GTAW welding procedures. The article concludes with a review of the safety precautions to avoid possible hazards during the GTAW process: electrical shock, fumes and gases, arc radiation, and fire and explosion.

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.

Laser has found its applications in cutting, drilling, and shock-peening operations of manufacturing industry because of its accurate, safe, and rapid cutting property. This article provides an account on the fundamental principles of laser cutting (thermal), drilling, and shock-peening processes of which emphasis is placed on thermal laser cutting. It details the principal set-up parameters, such as the laser beam output, nozzle design, focusing optic position and characteristics, assist gases, surface conditions, and cutting speed. A discussion on the types of gas, supply system, purity level, and flow rates of lasing and assist gases is also provided. The article also describes the metallurgies and other key material considerations that impact laser-cutting performances and includes examples of laser cutting of nonmetal materials.

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.

This article describes the benefits that can be achieved by using thermal spray on particular engine parts of an automobile. These include improvement in fuel consumption, wear resistance and bonding, and reduction of oil consumption, exhaust heat loss, and cooling heat loss. Typical engine parts are cylinder blocks, cylinder bores, cast iron cylinder liners, piston rings, connecting rod bearings, turbochargers, engine valve lifters, exhaust system parts, and oxygen sensors. The article also describes the benefits of using thermal spray on transmission parts such as synchronizer rings and torque converters.

This article focuses on friction, lubrication, and wear of internal combustion engine parts, improvements in which provide important gains in energy efficiency, performance, and longevity of the internal combustion (IC) engine systems. It discusses the types, component materials, and Friction and Wear Control of IC engine. The article explains the process of friction reduction by surface textures or coatings. It provides information on surface hardening of iron and steel, which is commonly employed for engine and powertrain components such as crankshafts, cams, and cylinder liners. The article also discusses advanced surface engineering technologies, such as diamondlike carbon coatings and surface texture technology. Information on thermal-spray methods that have led to improvements in engine components is also provided. The article describes IC engine-components wear, namely, piston assembly wear, valvetrain wear, cylinder-bore wear, and engine bearing wear. It concludes with information on inlet valve and seat wear of IC engine.

The primary fossil fuels are generally defined as coal, oil, natural gas, tar sands, and shale oil. This article discusses the characteristics and the types of fuels used in fossil and fuel industries. It describes the energy conversion in fuels and outlines the efficiency of a heat engine with the help of the Carnot equation.

Compacted graphite iron (CGI) invariably includes some nodular (spheroidal) graphite particles, giving rise to the definition of the microstructure in terms of percent nodularity. This article discusses the graphite morphology and mechanical and physical properties of CGI. The mechanical and physical properties of CGI with ferritic and pearlitic matrix structures are summarized in a table. The article describes the standards for CGI, with the definition of the grades based on the minimum tensile strength. It also provides information on the applications of compacted graphite iron castings.

Stretch forming is the forming of sheet, bars, and rolled or extruded sections over a die or form block of the required shape while the workpiece is held in tension. This article discusses the applicability, advantages, and machines and accessories of stretch forming. It provides a detailed discussion on four methods of stretch forming, namely, stretch draw forming, stretch wrapping, compression forming, and radial draw forming.

The process of case hardening of steel includes three consecutive steps of heat treatment: heating; the thermochemical process with the enrichment of the surface area during the carburizing or carbonitriding stage with carbon and nitrogen; and the subsequent quenching process for hardening. This article provides a model-based description of the development of residual stresses during case hardening. It also describes the influence and effects of residual stresses and distortion in hardening, carburizing, and nitriding processes of the steel.

This article presents the damage tolerance criteria for military composite aircraft structures to safely operate the structures with initial defects or in-service damage. It describes the effects of defects, such as wrinkles in aircraft structures, and the reduction in compressive strength and tensile strength. The article reviews low velocity impacts in aircraft structures in terms of resin toughness, laminate thickness, specimen size and impactor mass, and post-impact fatigue. It explains the tension strength analysis, such as linear elastic fracture mechanics and R-curve methods, to predict the residual strength of the structures.

Residual stresses are stresses within a part that result from non-uniform plastic deformation or heating and cooling and play a vital role in ensuring long life of the induction-hardened steel parts. This article provides a description of the formation of residual stresses, and factors affecting their magnitude and distribution as well as their effects on longevity of heat-treated components. The residual stresses of the induction-hardened part are often produced by microstructural transformation, thermal shrinking, distortion, and quenching. Fatigue strength is the main property that gets affected not only by induction hardening but also by residual stresses, quenching conditions, and grain size in the hardened condition. The article concludes with a review of induction heating or hardening in conjunction with other processing methods with examples in terms of properties and, in some cases, effects on residual stress.

Pumps and compressors are representative fluid machineries, which are indispensably important industrial equipment for water supply systems, chemical processing and reactions, and fluid power systems. This article addresses friction, lubrication, and wear of components in several types of machines such as positive displacement pumps including hydraulic pumps, turbo-pumps including centrifugal pumps, vacuum pumps, and compressors including the positive displacement type and turbo type.

Hammers and high-energy-rate forging machines are classified as energy-restricted machines as they deform the workpiece by the kinetic energy of the hammer ram. This article provides information on gravity-drop hammers, power-drop hammers, die forger hammers, counterblow hammers, and computer-controlled hammers. It describes the three basic designs of high-energy-rate forging (HERF) machines: the ram and inner frame, two-ram, and controlled energy flow. The article reviews forging mechanical presses, hydraulic presses, drive presses, screw presses, and multiple-ram presses.

This article summarizes some general alloy groupings by application or major characteristics. The groupings include cast rotor, general-purpose, elevated-temperature, wear-resistant, moderate-strength, high-strength, and high-integrity die casting alloys and cast aluminum alloys bearings. A table lists selected applications for aluminum casting alloys.

This article describes the methods for determining the flow rate of metal powders. It examines the factors affecting flow rate, apparent density, and angle of repose of metal powders. The article reviews the frictional properties, cohesive strength, frictional properties, tap density, and compressibility of metal powders. It explains the mechanisms of powder segregation. The article provides information on green strength and springback value of rectangular test bar. It concludes with a discussion on the chemical composition of metal powders.