This product working temperature is -35°C-130°C and suitable for throttling or shutting off the flow of corrosive or incorrosive gases, liquids, semliquids,semiliquids and solid powder, and can be installed in and selected position in pipelines or on vessels in the industries of petroleum processing, chemicals,food,medicine, textile,paper making, hydroelectricity engineering,Ship building,water supply and sewage,metallurgy,energy engineering as well as light industry,etc