METHOD FOR MANUFACTURING OVAL SWAGED COLLAR

摘要

A method for manufacturing an oval swaged collar having a flange (21) of a uniform thickness, for which a thin-walled section for attaining an expanded diameter can be formed with a uniform thickness, and a cross-section having the expanding diameter in a prescribed shape is oval in shape. A flanged cylindrical body is prepared. Next, the flanged cylindrical body is placed between concave surfaces (31a) of a pair of first dies (31) and between flat surfaces (32a) of a pair of second dies (32) which are arranged in an orthogonal direction to the first dies (31), the pair of first dies (31) are moved closer together such that the distance between the concave surfaces (31a) of the pair of first dies (31) becomes equal to the long axis length of a sleeve of the oval swaged collar to be manufactured, and the sleeve of the flanged cylindrical body is pressed in opposite directions using the flat surfaces (32a) of the pair of second dies (32). An oval swaged collar having a long axis in the direction of the first dies (31) and a short axis in the direction of the second dies (32) is formed. A pin is inserted inside the oval swaged collar as needed for forming the inner shape of the oval swaged collar.