| 摘要 |
This concerns a valve for preventing the total or partial vacuum that sometimes occurs in sewage piping. Normally it is installed close to the anti-siphon traps that accompany sewage piping, though they may also be fitted in sewage piping systems that do not incorporate anti-siphon traps, it also being possible to fit them in part of said traps. This valve guarantees the hydraulic seal of the traps, as well as preventing unpleasant odours from reaching the outside. <IMAGE> |
