SIC 3562 Ball and Roller Bearings

SIC 3562

This industry covers establishments primarily engaged in manufacturing ball and roller bearings (including ball or roller bearing pillow block, flange, takeup cartridge, and hangar units) and parts. Establishments primarily engaged in manufacturing plain bearings are classified in SIC 3568: Mechanical Power Transmission Equipment, Not Elsewhere Classified.

NAICS CODE(S)

332991

Ball and Roller Bearing Manufacturing

INDUSTRY SNAPSHOT

The ball and roller bearing industry is very large, but mature. It affects everything from the production of space shuttles to household appliances, automobiles, dentist drills, roller skates, and computer disk drives. In 2003 U.S. establishments involved in ball and roller bearing manufacturing shipped products valued at $5.7 billion.

The issues facing the bearing industry are both numerous and complex. As a secondary steel product manufacturing industry, it is in the middle of the production chain; however, policies favoring the steel industry may not be in the best interest of the bearing industry, and vice versa. Because bearings are essential components of military and civilian machinery and equipment, the federal government has historically been a major customer of the industry. Nonetheless, high labor and production costs have caused the bearing industry to lose business to foreign competitors who have been able to sell bearings of equal quality at lower prices. U.S. bearing companies also have had to contend with illegal dumping practices by foreign competitors. Found guilty of these practices, many perpetrators then turned around and either opened plants in the United States or bought plants to supply their American customers. By the early 2000s, American manufacturers were especially confronted with competition from Asian countries, most notably China.

ORGANIZATION AND STRUCTURE

The ball and roller bearing business is unusual because it is strictly a component manufacturing industry. The industry accommodates its markets by selling loose or packaged bearings; these packaged bearings are installed in races that allow manufacturers to interchange complete bearing components. The industry has continued to evolve by developing new materials and lubricants and searching for alternative uses for bearings. Bearings have been found to have almost limitless applications and are expected to be in demand as long as machines are manufactured.

Ball bearings are spherical in shape, whereas roller bearings are cylindrical and may be tapered on one end or flattened to resemble needles. Generally, a ball bearing is used when speed is important; a roller bearing is used more often when load is most important. The manufacture of antifriction bearings starts from rod or wire. In a typical production process, pieces of wire are cut off in a press, placed between dies, and pressed into the shape of a ball or roller. Large rollers are produced by machining turning processes. The fin of surplus material that forms in the pressing process is removed between rotating file discs, and the diameter of the bearings is reduced through grinding and tumbling processes. Roundness specifications and surface finish improvements are also attained during grinding and tumbling. The bearings are then hardened, tempered, and given a high polish by further tumbling with a polishing agent. Finally, the elements are graded according to diameter.

Ball and roller bearings are used in anything that slides, glides, or rolls and, in some cases, are as large as 15 meters in diameter. Two general classes of bearings exist: commodity and precision. Commodity bearings are used in rotating elements that have relatively low revolutions per minute and do not face extreme stresses. Precision bearings, on the other hand, are highly accurate in terms of material quality, consistency of finish and diameter, and repeatability of tolerance levels. These bearings go through rigorous tests that check internal structure for failure tendencies and measure diameters to within one-millionth of an inch. Because the bearing industry has achieved such high product standards, it is widely respected for its ability to ensure an extraordinarily high level of quality control.

The primary materials consumed by the industry include alloy steel mill shapes. Cold steel and iron forgings, however, are also widely used in the bearing industry. Other materials and devices used by the industry include raw and composite ceramics; electric motors; machine cutting tools; grinding wheels; powdered metals; copper wire; stainless steel sheets; carbon steel bars; and iron, steel, and copper scrap.

Traditionally, manufacturers of motor vehicles and their parts and accessories are the largest consumer of U.S. bearing industry output, often accounting for more than 15 percent of production. The next four leading sectors for the industry are exports at about 10 percent; ball and roller bearings at about 7 percent; telephone and telegraph communications at about 6 percent; and blast furnaces and steel mills at about 4 percent. The mining, oil drilling, and metalworking industries also are heavy consumers of antifriction bearings. Additionally, bearings of various types and sizes are widely used in refrigeration and heating equipment, motors and generators, aircraft and related parts, and railroad equipment.

Antifriction bearings offer several advantages to machine designers. The friction placed on the bearings due to loads exerted is much lower than for other types of bearings. It is the lack of bearing friction that prevents excessive wear and abrasions on machines that start and stop while loads are applied. Automobile parts are examples of elements that benefit from less friction and wear. Roller bearings, in particular, are easily lubricated, can...