TORSION BEAM AND TORSION BEAM PRODUCING METHOD

摘要

PURPOSE: A torsion beam and a molding method thereof are provided to reduce weight of a car by excluding the need of a welding reinforcement, to improve durability of a weld zone, and to increase the amount of welding heat input. CONSTITUTION: A torsion beam molding method comprises the following steps. A tube is prepared (S10). The end of the prepared tube is bent to have a fixed angle (S20). The tube with the bent end is cut to have a feeding unit parallel with a weld zone after being cut (S25). The end of the bent tube is free-formed for the bent tube to be inserted in a mold of a hydroforming process (S30). The free formed tube which is inserted into the mold has both sides to be blocked; an axle punch is inserted into the end of the tube to apply hydraulic presser to the inside of the tube; and the tube is hydro-formed to be a mold shape (S40). The bending part bent in the tube expanded to the hydroforming. The bending part, which is bent from the tube which is expanded by hydroforming, is cut to be a shape corresponding to a trailing arm (S50). [Reference numerals] (AA) Completion of a torsion beam; (S10) Prepare a tube; (S20) Bend an end of the tube; (S30) Perform pre-forming; (S40) Perform hydro-forming; (S50) Cut the bending part