Sheet Metal Workers
Sheet metal workers fabricate or install products that are made from thin metal sheets, such as ducts used for heating and air-conditioning.
Sheet metal workers typically do the following:
- Select types of sheet metal or nonmetallic material
- Measure and mark dimensions and reference lines on metal sheets
- Drill holes in metal, for screws, bolts, and rivets
- Install metal sheets with supportive frameworks
- Fabricate or alter parts at construction sites
- Maneuver large parts to be installed, and anchor the parts
- Fasten seams or joints by welding, bolting, riveting, or soldering
Sheet metal workers make, install, and maintain thin sheet metal products. Although sheet metal is used to make many products, such as rain gutters, outdoor signs, and siding, it is most commonly used to make ducts for heating and air-conditioning.
Sheet metal workers study plans and specifications to determine the kind and quantity of materials they will need. Using computer-controlled saws, lasers, shears, and presses, they measure, cut, bend, and fasten pieces of sheet metal.
In shops without computerized equipment, sheet metal workers make the required calculations and use tapes and rulers to lay out the work. Then, they cut or stamp the parts with machine tools.
In manufacturing plants, sheet metal workers program and operate computerized metalworking equipment. For example, they may make sheet metal parts for aircraft or industrial equipment. Sheet metal workers in those jobs may be responsible for programming the computer control systems of the equipment they operate.
Before assembling pieces, sheet metal workers check each part for accuracy. If necessary, they use hand, rotary, or squaring shears and hacksaws to finish pieces.
After inspecting the metal pieces, workers fasten seams and joints with welds, bolts, rivets, solder, or other connecting devices. Then they take the parts constructed in the shop and assemble the pieces further as they install them.
Most fabrication work is done in shops with some final assembly done on the job. Some jobs are done completely at the jobsite. When installing a metal roof, for example, sheet metal workers usually measure and cut the roofing panels onsite.
In addition to installing sheet metal, some workers install fiberglass and plastic board.†
In some shops and factories, sheet metal workers care for and maintain the equipment they use.†
Sheet metal workers do both construction-related work and the mass production of sheet metal products in manufacturing. Sheet metal workers are often separated into four specialties: fabrication, installation, maintenance, and testing and balancing. The following describes these types of sheet metal workers:
Fabrication sheet metal workers, sometimes called precision sheet metal workers, make ducts, gutters, and other metal products. Most work in shops and factories, operating tools and equipment. Although some of the fabrication techniques used in large-scale manufacturing are similar to those used in smaller shops, the work may be highly automated and repetitive. Many fabrication shops have automated machinery, and workers use computer-aided drafting (CAD) and building information modeling (BIM) systems to make products.
Installation sheet metal workers install heating, ventilation, and air-conditioning (HVAC) ducts. They also install other sheet metal products, such as metal roofs, siding, or gutters. They work on new construction and on renovation projects.†
Maintenance sheet metal workers repair and clean ventilation systems so the systems use less energy. Workers remove dust and moisture and fix leaks or breaks in the sheet metal that makes up the ductwork.
Testing and balancing sheet metal specialists ensure that HVAC systems heat and cool rooms properly. They ensure that hot and cold air is transferred through sheet metal ducts efficiently. For more information on workers who install or repair HVAC systems, see the profile on heating, air conditioning, and refrigeration mechanics and installers.
Welders, Cutters, Solderers, and Brazers
Welders, cutters, solderers, and brazers weld or join metal parts. They also fill holes, indentions, or seams of metal products, using hand-held welding equipment.†
†Welders, cutters, solderers, and brazers typically do the following:
- Study blueprints, sketches, or specifications
- Calculate dimensions to be welded
- Inspect structures or materials to be welded
- Ignite torches or start power supplies
- Monitor the welding process to avoid overheating
- Smooth and polish all surfaces
- Maintain equipment and machinery
Welding is the most common way of permanently joining metal parts. In this process, heat is applied to metal pieces, melting and fusing them to form a permanent bond. Because of its strength, welding is used in shipbuilding, automobile manufacturing and repair, aerospace applications, and thousands of other manufacturing activities. Welding also is used to join beams in the construction of buildings, bridges, and other structures and to join pipes in pipelines, power plants, and refineries.
Welders work in a wide variety of industries, from car racing to manufacturing. The work that welders do and the equipment they use vary, depending on the industry. The most common and simplest type of welding today, arc welding, uses electrical currents to create heat and bond metals togetheróbut there are more than 100 different processes that a welder can use. The type of weld is normally determined by the types of metals being joined and the conditions under which the welding is to take place.
Cutters use heat to cut and trim metal objects to specific dimensions. The work of arc, plasma, and oxy-gas cutters is closely related to that of welders. However, instead of joining metals, cutters use the heat from an electric arc, a stream of ionized gas called plasma, or burning gases to cut and trim metal objects to specific dimensions. Cutters also dismantle large objects, such as ships, railroad cars, automobiles, buildings, or aircraft. Some operate and monitor cutting machines similar to those used by welding machine operators.
Solderers and brazers also use heat to join two or more metal items together. Soldering and brazing are similar, except the temperature used to melt the filler metal is lower in soldering. Soldering uses metals with a melting point below 840 degrees Fahrenheit. Brazing uses metals with a higher melting point.†
Soldering and brazing workers use molten metal to join two pieces of metal. However, the metal added during the soldering and brazing process has a melting point lower than that of the piece, so only the added metal is melted, not the piece. Therefore, these processes normally do not create the distortions or weaknesses in the pieces that can occur with welding.
Soldering commonly is used to make electrical and electronic circuit boards, such as computer chips. Soldering workers tend to work with small pieces that must be precisely positioned.
Brazing often is used to connect copper plumbing pipes and thinner metals that the higher temperatures of welding would warp. Brazing also can be used to apply coatings to parts to reduce wear and protect against corrosion.