Application The throttling butterfly valves are valves to regulation medium flow rate, which can flow by both ways. The throttling butterfly valves aren’t closing valves. Working medium air water non-aggressive liquids gases Maximum working temperature A working temperature is from - 50 °C up to + 500 °C and depends on the body and gland packing material. Technical description The disc is pivoted by operating shaft in the body. The angle displacement of the disc is 0-90°. Disc position is shown by indicator line on the shaft, on the lever eventually on the electric actuator. There is always a  gap between disc and body in closed position for type L35.18. In case of butterfly valve design with sealing collar (type L35.38) then the gap is limited to shaft area merely