U pruduttu veni usatu di throttling o shutting nantu à a purtata di liquids currusivi o micca currusivi gased, è liquidu punti.

U valves porta sò anchiamènti usatu in acqua, Stati Uniti, impianti, custruzione, pitroliu, nnustria chìmica, food, midicina, roba, putenza, navi, di metallurgia

Check valve is a kind of valve whose opening and closing parts are round valve disc, which can block the reverse flow of medium by its own weight and medium pressure

U francese valve hè anchiamènti usatu in adminstration municipali, conservancy acqua, malu impianti etc.

It is used in gas medium pipeline system of industrial and mining enterprises, municipal administration, environmental protection and other industries, especially suitable for absolute cut off of toxic, harmful and flammable gases.

Air damper is suitable for flue gas, dusty gas etc.