| 摘要 |
<p>PURPOSE:To reduce a muck dropping noise by forming a joint inner wall surface layer, in a part on which a connection port inside cross sectional shape is projected when parallel light is radiated to the central axis of the pipe connecting port, of an elastic material having specific hardness and thickness in a pipe joint having a bend pipe part. CONSTITUTION:A joint body 2 is formed of cast iron, and has a bend pipe part 23 between a vertical pipe connecting port 21 and a horizontal pipe connecting port 22, and the wall surface of the bend pipe part 23 on which an inside cross sectional shape of the vertical pipe connecting port 21 is projected when parallel light is radiated to the central axis of the connecting port 21, is swollen outside of a pipe, and a recessed part 24 is formed inside of it. An elastic material layer 3, whose surface layer has Shore D hardness equal to or lower than 50 degree and thickness equal to or thicker than 5 millimeter, is formed in this part. Since a part of muck dropping energy is absorbed by the elastic material layer 3, vibration is reduced in a joint part, so that a generating noise can be also reduced. It is preferable to set the elastic material layer 3 surface and the other part surface on the same plane. Natural rubber, synthetic rubber, a synthetic resin elastomer material or their foaming body can be listed as a construction material for an elastic materal.</p> |
