| 摘要 |
<p>A cleanout fitting has a tubular body adapted to be connected between a pair of conduits and having an upwardly open well defined between the upstream and downstream end of the body. This tubular body is formed internally with a downward upstream step and a downward downstream step. At its upstream step the body is also formed with a downwardly U-shaped abutment forming a downstream-facing upstream insert seat. At its downstream step the body has a plurality of ridges defining an upwardly open U-shaped seat. Inserts, normally check valves, have rings receivable in these seats and each have a valve flap engageable with the respective ring. A cover is sealingly engageable over the well, and also serves to hold at least the downstream insert in place in the respective seat.</p> |
