摘要 |
Improvement of the bursting strength of a flexible pipe relative to a nipple, and flow rate adjustment in the nipple, are simultaneously achieved in sheet metal processing. A flexible pipe (1) is inserted (in an insertion space (S)) between a crimped pipe (3) and a nipple (2) formed into cylindrical shapes in sheet metal processing, whereby a gap can be formed between the positioned flexible pipe (1) and the small-diameter part (2a) of the nipple (2). In this state, the crimped pipe (3) is deformed so as to be constricted toward the flexible pipe (1), whereby the material (1m) of the flexible pipe (1), which has flowed along with the constricting deformation, then flows into an engaging concavity (2c). At the same time, the material (1m) of the flexible pipe (1), having flowed into the engaging concavity (2c), engages with a restraining ridge (2d) in the pull-out direction (U) of the flexible pipe (1), and the pull-out movement of the flexible pipe (1) is inhibited. A flow-channel narrow part (2h) is formed protruding toward a flow channel space (W) on the inner side of the small-diameter part (2a) in sheet metal processing, and the area of the fluid passing through the flow channel space (W) of the nipple (2) therefore decreases in the flow-channel narrow part (2h). |