Cold-Finished Steel Bars

Abstract

Abstract Cold-finished steel bars are carbon and alloy steel bar products (round, square, hexagonal, flat, or special shapes) that are produced by cold finishing previous hot-wrought bars. by means of cold drawing, cold forming, turning, grinding, or polishing (singly or in combination) to yield straight lengths or coils that are uniform throughout their length. Cold-finished bars fall into five classifications: cold-drawn bars; turned and polished bars; cold-drawn, ground, and polished bars; turned, ground, and polished bars; cold-drawn, turned, ground, and polished bars. Different size tolerances are applicable to cold-finished products, depending on shape, carbon content, and heat treatment. When used to identify cold-finished steel bars, the various quality descriptors are indicative of many characteristics, such as degree of internal soundness, relative uniformity of chemical composition, and relative freedom from detrimental surface imperfections. Cold drawing significantly increases machinability, tensile and yield strengths of steel bars. Two special die-drawing processes have been developed to give improved properties over those offered by standard drawing practices. These processes are cold drawing using heavier-than-normal drafts, followed by stress relieving; and drawing at elevated temperatures.