Tee type connector pipe manufacturing method

A tee type connector pipe manufacturing method, comprising:

• a step S-1, in which an oval-shaped molding hole (11) is drilled in the center of a metal plate (10), and then the metal plate (10) is roll-formed into a tube-shaped straight pipe (20);
• a step S-2, settling down a jig pipe (100), which has a seating place (110) formed in an inner side and a circular-shaped insertion hole (120) formed in a center, in a lower mold (200);
• a step S-3, positioning a molding stone (300), which has a curved outer circumferential surface, into the seating place (110) through the insertion hole (120);
• a step S-4, positioning the straight pipe (20) to an outer side of the jig pipe (100);
• a step S-5, combining and securing an upper mold (400) with the lower mold (200);
• a step S-6, combining the molding stone (300) with a shaft (510) of a press device (500) that has passed through a pass-through hole (410) formed in the upper mold (400);
• a step S-7, lifting the shaft (510) to forcibly pass the molding stone (300) through the molding hole (11) to form a molding pipe part (31), then to form a tee type pipe (30);
• and
• a step S-8, disuniting the upper mold (400) and the lower mold (200), and separating the tee type pipe (30) from the jig pipe (100)
• wherein, in the step S-1, a ratio between the diameter (d) of the straight pipe (20) and the minor axis diameter (b) of the molding hole (11) is 1:0.4, and a ratio between the minor axis diameter (b) and the major axis diameter (c) of the molding hole (11) is 1:2, and
• wherein, in the step S-3, a radius (r) of an outer circumferential surface of the molding stone (300) is same to a radius (d) of the straight pipe (20).