* It Is used for conveying air and other gases of non Spontaneous Combustion, Physical harmless, Non-corrosive to steel. It is not allowed to transfer gas containing dust sticky particles, the content of hard particles no more than 150 mg/m3, the gas temperature no higher than 80℃. It Is suitable for Metallurgy, Foundry, Glass, Porcain, electrcoplate, storage battery, food, feed, minerals and other fields.