Drawing (manufacturing)

Drawing is a manufacturing process that uses tensile forces to elongate metal, glass, or plastic.

For wire, bar, and tube drawing, the starting stock is drawn through a die to reduce its diameter and increase its length.

Drawing is usually performed at room temperature, thus classified as a cold working process; however, drawing may also be performed at higher temperatures to hot work large wires, rods, or hollow tubes in order to reduce forces.

Drawing metal requires finding the correct balance between wrinkles and breaking to achieve a successful part.

Bar, tube, and wire drawing all work upon the same principle: the starting stock is drawn through a die to reduce its diameter and increase its length.

Cold drawn cross-sections are more precise and have a better surface finish than hot extruded parts.

To achieve a certain size or shape, multiple passes through progressively smaller dies and intermediate anneals may be required.

[9] It is performed after the material has been "spun" into filaments; by extruding the polymer melt through pores of a spinneret.

These filaments still have an amorphous structure, so they are drawn to align the fibers further, thus increasing crystallinity, tensile strength, and stiffness.