Applies to establishments engaged in operating foundries that manufacture castings from ferrous and/or nonferrous metals. To form castings, metal is melted in furnaces, then poured or ladled into molds. After they are cooled and solidified, castings are removed from molds with shake out machines, or tools such as torches, electric arcs, abrasive saws, or sledgehammers. Depending on the product and the carbon or alloy content of the metal, further repair or refining such as welding, annealing, tempering, flame hardening or other heat treatments may be needed. Cleaning and finishing processes include, but are not limited to, machining, chipping, grinding, shot or sandblasting, tumbling, and acid pickling to remove surface defects, inspection (sometimes by radiation or chemical analysis) and painting or powder coating. Foundries may make their own patterns and mold, and/or perform their own finishing processes, or they may contract these activities out to pattern-making shops or to machine shops.

This classification excludes establishments that perform only pattern making functions which are to be reported separately in classification 2906 and establishments engaged exclusively in machine shop services which are to be reported separately in classification 3402.

Special note: Foundries that make their own patterns and/or perform their own machine finishing may report those operations separately in the classifications applicable to the work being performed provided all of the conditions of the general reporting rule covering the operation of a secondary business activity have been met.