| 摘要 |
A curved portion (14A) at an inner circumferential face (15) on a bend direction inside of a bend (14) has a circular arc shape. By configuring the curved portion with a circular arc shape, a recess (16), serving as an example of a cross-sectional area enlargement portion that enlarges the cross-sectional area of a flow path of a pipe body (12) running along a direction of an axial line 13, is formed in the inner circumferential face (15) on the bend direction inside of the bend (14). |
