Converting raw materials to marketable products is the backbone of an industrialized nation. The greater the manufacturing activity level, the higher a country’s standard of living. Although the increases in a country’s manufacturing activity level are due in part to the strides made in manufacturing technology and processes, the basic processes remain the same: casting and molding, shearing and forming, machining and joining.
Casting and Molding
Manufacturers use a casting process to produce items of a particular shape that would be difficult to create by another means. Usually, the casting process entails pouring a liquid material, such as metal, into the hollow cavity of a mold and allowing the liquid to solidify. Once hardened or set, the casting is removed from the mold. A factory molds liquid or a pliable material, such as glass, plastic, ceramic materials or metal, in a frame referred to as a matrix or mold. The material is poured into the frame, and it remains there until the material assumes the shape of the frame. Examples of molded products include engine blocks, pistons, household goods and furniture.
Machining cuts a piece of material into a desired shape and, in the process, removes part of the material. Machining -- also referred to as subtractive manufacturing – involves a combination of machine tools, such as drill presses and milling machines, along with cutting tools to create an end product with a specific geometry and surface finish. Machining is used to cut metal, wood, plastic, ceramic and composites to create gears, bearings, clutches, screws and nuts. Types of machining include drilling, turning, boring, milling, sawing, grinding and filing. Like molding and casting, machining is primarily concerned with the production of components.
Joining includes welding, brazing, soldering, adhesive bonding and mechanical joining using fasteners, such as rivets or pins. Joining is performed if a product cannot be manufactured as one piece but rather as a combination of different components. Joining is also used if it’s less expensive to transport individual components and assemble them at a final destination.
Shearing and Forming
Manufacturers shear material to a particular shape and size using punching, piercing, blanking, cutting and trimming functions. Materials that are sheared include sheet metal and rods, plastic and paper. In turn, a manufacturer can form or shape parts by forcing material, such as metal, through a die. Forming operations include roll bending, extruding, drawing and spinning.
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