| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a drain pipe of the structure capable of effectively restraining the generation of a noise or vibration by the internal water flow. SOLUTION: This drain pipe has a spirally extending guide projection streak 12 formed on the inner wall of a cylindrical pipe body 11. Since the water running in the drain pipe having such a structure is spirally rotated by the guide effect of the spiral guide projection streak 12 and carried while it is pressed onto the inner surface of the pipe body 11 by the centrifugal force at this time, a turbulence causing a noise is hardly generated, the flow velocity to the pipe axial direction is reduced to moderate the impact by the collision of the water to the pipe inner wall, and the rigidity of the pipe body 11 is also increased.</p> |
