| 摘要 |
In the welding method of tubular members made of a thermoplastic synthetic resin, end faces to be welded, of a pair of tubular members are melted by heat of a heater, and the end faces are urged against each other to be welded. Prior to the melting of the end faces, each of the end faces is processed to a shape comprising a flat, annular, outer portion and a flat, annular, inner portion. The inner portion and outer portion both are perpendicular to the center axis of the tubular member, and the outer portion is set outside the inner portion along the center axis. Such a welding method can minimize the bead formed on the inner circumferential surface and can achieve a high weld strength. <IMAGE> |
