| HOME | FAQ | Books |
Links |
AMAZON multi-meters discounts AMAZON oscilloscope discounts QUICK FACTS about this job:
AMAZON multi-meters discounts AMAZON oscilloscope discounts OVERVIEW Welders operate a variety of special equipment to join metal parts together
permanently, usually using heat and sometimes pressure. They work on
constructing and repairing automobiles, aircraft, ships, buildings, bridges,
highways, appliances, and many other metal structures and manufactured
products. HISTORY Although some welding techniques were used more than 1,000 years ago in forging iron blades by hand, modern welding processes were first employed in the latter half of the 1800s. From experimental beginnings, the pioneers in this field developed a wide variety of innovative processes. These included resistance welding, invented in 1877, in which an electric current is sent through metal parts in contact. Electrical resistance and pressure melt the metal at the area of contact. Gas welding, also developed in the same era, is a relatively simple process using a torch that burns a gas such as acetylene to create enough heat to melt and fuse metal parts. Oxyacetylene welding, a version of this process developed a few years later, is a common welding process still used today. Arc welding, first used commercially in 1889, relies on an electric arc to generate heat. Thermite welding, which fuses metal pieces with the intense heat of a chemical reaction, was first used around 1900. In the last century, the sudden demand for vehicles and armaments and a growing list of industrial uses for welding that resulted from the two world wars have spurred researchers to keep improving welding processes and also have encouraged the development of numerous new processes. Today, more than 80 different types of welding and welding-related processes are in use. Some of the newer processes include laser-beam welding and electron-beam welding. THE JOB Robotic technology perform much of the welding processes that are necessary in the motor and vehicle parts manufacturing industry, but welders are still needed to fix mistakes that have occurred during manufacturing and weld materials in processes that can't easily be automated. Welders use various kinds of equipment and processes to create the heat and pressure needed to melt the edges of metal pieces in a controlled fashion so that the pieces may be joined permanently. The processes can be grouped into three categories. The arc welding process derives heat from an electric arc between two electrodes or between an electrode and the workpiece. The gas welding process produces heat by burning a mixture of oxygen and some other combustible gas, such as acetylene or hydrogen. The resistance welding process obtains heat from pressure and resistance by the workpiece to an electric current. The arc and gas methods can also be used to cut, gouge, or finish metal. Depending on which of these processes and equipment they use, welders may be designated arc welders, gas welders, or acetylene welders. Or they may be combination welders, meaning they use a combination of gas and arc welding, or welding machine operators, meaning they operate machines that use an arc welding process, electron-beam welding process, laser-beam welding process, or friction welding process. Other workers in the welding field include resistance machine welders; oxygen cutters, who use gas torches to cut or trim metals; and arc cutters, who use an electric arc to cut or trim metals. Skilled welders usually begin by planning and laying out their work based on drawings, blueprints, or other specifications. Using their working knowledge of the properties of the metal, they deter mine the proper sequence of operations needed for the job. They may work with steel, stainless steel, cast iron, bronze, aluminum, nickel, and other metals and alloys. Metal pieces to be welded may be in a variety of positions, such as flat, vertical, horizontal, or overhead. In the manual arc welding process (the most commonly used method), welders grasp a holder containing a suitable electrode and adjust the electric current supplied to the electrode. Then they strike an arc (an electric discharge across a gap) by touching the electrode to the metal. Next, they guide the electrode along the metal seam to be welded, allowing sufficient time for the heat of the arc to melt the metal. The molten metal from the electrode is deposited in the joint and , together with the molten metal edges of the base metal, solidifies to form a solid connection. Welders determine the correct kind of electrode to use based on the job specifications and their knowledge of the materials. In gas welding, welders melt the metal edges with an intensely hot flame from the combustion of fuel gases in welding torches. First, they obtain the proper types of torch tips and welding rods, which are rods of a filler metal that goes into the weld seam. They adjust the regulators on the tanks of fuel gases, such as oxygen and acetylene, and they light the torch. To obtain the proper size and quality of flame, welders adjust the gas valves on the torch and hold the flame against the metal until it's hot enough. Then they apply the welding rod to the molten metal to supply the extra filler needed to complete the weld. Maintenance welders, another category of welding workers, may use any of the various welding techniques. They travel to construction sites, utility installations, and other locations to make on-site repairs to metalwork. Some workers in the welding field do repetitive production tasks using automatic welding equipment. In general, automatic welding is not used where there are critical safety and strength requirements. The surfaces that these welders work on are usually in only one position. Resistance machine welders often work in the mass production of parts, doing the same welding operations repeatedly. To operate the welding machine, they first make adjustments to control the electric current and pressure and then feed in and align the workpieces. After completing the welding operation, welders remove the work from the machine. Welders must constantly monitor the process to make sure that the machine is producing the proper weld. To cut metal, oxygen cutters may use hand-guided torches or machine-mounted torches. They direct the flame of burning oxygen and fuel gas onto the area to be cut until it melts. Then, an additional stream of gas is released from the torch, which cuts the metal along previously marked lines. Arc cutters follow a similar procedure in their work, except that they use an electric arc as the source of heat. As in oxygen cutting, an additional stream of gas may be released when cutting the metal. Welding technicians fill positions as supervisors, inspectors, experimental technicians, sales technicians, assistants to welding engineers, and welding analysts and estimators. Some technicians work in research facilities, where they help engineers test and evaluate newly developed welding equipment, metals, and alloys. When new equipment is being developed or old equipment improved, they conduct experiments on it, evaluate the data, and then make recommendations to engineers. Other welding technicians, who work in the field, inspect welded joints and conduct tests to ensure that welds meet company standards, national code requirements, and customer job specifications. These technicians record the results, prepare and submit reports to welding engineers, and conduct welding personnel certification tests according to national code requirements. Some beginning welding technicians are employed as welding operators. They perform manual, automatic, or semiautomatic welding jobs. They set up work, read blueprints and welding-control symbols, and follow specifications set up for a welded product. As welding inspectors, welding technicians judge the quality of incoming materials, such as electrodes, and of welding work being done. They accept or reject pieces of work according to required standards set forth in codes and specifications. A welding inspector must be able to read blueprints, interpret requirements, and have a knowledge of testing equipment and methods. Closely related to this work is that of the welding qualification technician. This person keeps records of certified welders and super vises tests for the qualification of welding operators. Other welding technicians work as welding process-control technicians. These technicians set up the procedures for welders to follow in various production jobs. They specify welding techniques, types of filler wire to be used, ranges for welding electrodes, and time estimates. Welding technicians also provide instructions concerning welding symbols on blueprints, use of jigs and fixtures, and inspection of products. Equipment maintenance and sales technicians work out of welding supply houses. They set up equipment sold by their company, train welding operators to use it, and troubleshoot for customers. REQUIREMENTS High School High school graduates are preferred for trainee positions for skilled jobs. Useful high school courses for prospective welders include mathematics, blueprint reading, mechanical drawing, applied physics, and shop. If possible, the shop courses should cover the basics of welding and working with electricity. Postsecondary Training Many welders learn their skills through formal training programs in welding, such as those available in many community colleges, technical institutes, trade schools, and the armed forces. Some programs are short term and narrow in focus, while others provide several years of thorough preparation for a variety of jobs. A high school diploma or its equivalent is required for admission into these programs. Beginners can also learn welding skills in on- the-job training programs. The length of such training programs ranges from several days or weeks for jobs requiring few skills to a period of one to three years for skilled jobs. Trainees often begin as helpers to experienced workers, doing very simple tasks. As they learn, they are given more challenging work. To learn some skilled jobs, trainees supplement their on-the-job training with formal class room instruction in technical aspects of the trade. Various programs sponsored by federal, state, and local governments provide training opportunities in some areas. These training programs, which usually stress the fundamentals of welding, may be in the classroom or on the job and last from a few weeks to a year. Apprenticeship programs also offer training. Apprenticeships that teach a range of metalworking skills, including the basics of welding, are run by trade unions such as the International Association of Machinists and Aerospace Workers. Certification or Licensing To do welding work where the strength of the weld is a critical factor (such as in automobiles, aircraft, bridges, boilers, or high-pressure pipelines), welders may have to pass employer tests or standardized examinations for certification by government agencies or professional and technical associations. Other Requirements Employers generally prefer to hire applicants who are in good enough physical condition to bend, stoop, and work in awkward positions. Applicants also need manual dexterity, good eye-hand coordination, and good eyesight, as well as patience and the ability to concentrate for extended periods as they work on a task. Many people in welding and related occupations belong to one of the following unions: International Association of Machinists and Aerospace Workers; International Brotherhood of Boilermakers, Iron Ship Builders, Blacksmiths, Forgers and Helpers; International Union, United Automobile, Aerospace and Agricultural Implement Workers of America; United Association of Journeymen and Apprentices of the Plumbing and Pipe Fitting Industry of the United States and Canada; or United Electrical, Radio, and Machine Workers of America. EXPLORING With the help of a teacher or a guidance counselor, students may be able to arrange to visit a workplace where they can observe welders or welding machine operators on the job. Ideally, such a visit can provide a chance to see several welding processes and various kinds of welding work and working conditions, as well as an opportunity to talk with welders about their work. EMPLOYERS Workers in welding occupations work in a variety of settings. About two-thirds of welders are employed in manufacturing plants that produce motor vehicles and parts, ships, boilers, machinery, appliances, and other metal products. Most of the remaining welders work for repair shops or construction companies that build bridges, large buildings, pipelines, and similar metal structures. All welding machine operators work in manufacturing industries. Approximately 28,000 welders and related workers are employed in the motor vehicle and parts manufacturing industry. Employers include the Big Three U.S. automobile makers (Chrysler LLC, Ford Motor Company, and General Motors), major foreign automakers that have factories or divisions in the United States (BMW, Honda, Hyundai, Mercedes-Benz, Nissan, Toyota), as well as any of the thousands of private manufacturing companies. cif-automotive-164.jpg A worker welds a vehicle at a manufacturing plant. STARTING OUT Graduates of good training programs in welding often receive help in finding jobs through their schools’ career services offices. The classified ads sections of newspapers often carry listings of local job openings. Information about openings for trainee positions, apprenticeships, and government training programs, as well as jobs for skilled workers, may be available through the local offices of the state employment service and local offices of unions that organize welding workers. Job seekers also can apply directly to the personnel offices at automotive manufacturers that hire welders. ADVANCEMENT Advancement usually depends on acquiring additional skills. Workers who gain experience and learn new processes and techniques are increasingly valuable to their employers, and they may be promoted to positions as supervisors, inspectors, or welding instructors. With further formal technical training, welders may qualify for welding technician jobs. Some experienced welders go into business for themselves and open their own welding and repair shops. Welding technicians can become welding supervisors and take on the responsibility of assigning jobs to workers and showing them how the tasks should be performed. They must supervise job performance and ensure that operations are performed correctly and economically. Other technicians become welding instructors, teaching welding theory, techniques, and related processes. Finally, some technicians advance to the position of welding production manager, responsible for all aspects of welding production: equipment, materials, process control, inspection, and cost control. EARNINGS According to the U.S. Department of Labor, welders employed in motor vehicle manufacturing earned median wages of $20.62 an hour in 2006 ($42,890 annually). Those employed in motor vehicle parts manufacturing earned $15.14 an hour in 2006 (or $31,491 annually). Salaries for all welders ranged from less than $20,970 to $46,800 or more. In addition to wages, employers often provide fringe benefits, such as health insurance plans, paid vacation time, paid sick time, and pension plans. Salaries for welding technicians vary according to the individual’s function and level of education as well as the geographic location of the business. WORK ENVIRONMENT Welders may spend their workday inside in well-ventilated and well- lighted shops and factories, outside at a construction site, or in con fined spaces, such as in an underground tunnel or inside a large storage tank that's being built. Welding jobs can involve working in uncomfortable positions. Sometimes welders work for short periods in booths that are built to contain sparks and glare. In some jobs, workers must repeat the same procedure over and over. Welders often encounter hazardous conditions and may need to wear goggles, helmets with protective faceplates, protective clothing, safety shoes, and other gear to prevent burns and other injuries. Many metals give off toxic gases and fumes when heated, and workers must be careful to avoid exposure to such harmful substances. Other potential dangers include explosions from mishandling combustible gases and electric shock. Workers in this field must learn the safest ways of carrying out welding work and always pay attention to safety procedures. Various trade and safety organizations have developed rules for welding procedures, safety practices, and health precautions that can minimize the risks of the job. Operators of automatic welding machines are exposed to fewer hazards than manual welders and cutters, and they usually need to use less protective gear. OUTLOOK Employment for welders in motor vehicle and parts manufacturing is expected to decline through 2016, according to the U.S. Department of Labor (USDL). In automotive manufacturing, the trend toward increasing automation, including more use of welding robots, is expected to decrease the demand for manual welders and increase the demand for welding machine operators. Overall employment in welding and related occupations is expected to grow more slowly than the average for all occupations through 2014, according to the USDL. Plenty of opportunities should exist for skilled welders, since many employers have difficulties in finding qualified applicants. Most job openings will develop when experienced workers leave their jobs. During periods when the economy is in a slowdown, many workers in construction and manufacturing, including some welders, may be laid off. FOR MORE INFORMATION For more information about becoming a welder, contact the following organizations: American Welding Society 550 Northwest Lejeune Road Miami, FL 33126-5649 Tel: 800-443-9353 International Association of Machinists and Aerospace Workers 9000 Machinists Place Upper Marlboro, MD 20772-2687 Tel: 301-967-4500 Email: websteward@goiam.org http://www.iamaw.orgPrev: Test Drivers |