MANUFACTURING APPARATUS AND METHOD OF BUSHING FOR HEAVY EQUIPMENT

摘要

A manufacturing apparatus and a manufacturing method of a bushing for a heavy equipment are provided to manufacture the bushing having high strength and high wear resistance by extruding the hollow shaft as a postprocess after performing a rear pressurization piercing process of converting a bushing manufacturing method into a forging process. A manufacturing method of a bushing for a heavy equipment comprises: a cutting step(S100) of cutting a cylindrical workpiece with a predetermined diameter into a first workpiece with a desired length; a heat-treating and lubricating step(S200) of heating the first workpiece to change mechanical properties of the first workpiece cut by the cutting step, and lubricating an outer peripheral surface of the heat-treated first workpiece; a first forging step(S300) of respectively pressurizing and piercing central portions of top and bottom faces of the first workpiece passing through the heat-treating and lubricating step to form a second workpiece; a second forging step(S400) of pressurizing a top face of the second workpiece having a hollow part formed therein through the first forging step, thereby decreasing cross-sectional diameter of the second workpiece and increasing length of the second workpiece to form a third workpiece; and a surface treatment step(S500) of removing unnecessary portions formed on a surface of the third workpiece formed through the second forging step to complete a bushing.