This standard applies to industrial pipeline fittings - butterfly valves (hermetic valves) used in
GOST 12521-1989 Referenced Document
GOST 15150-1969 Machines, instruments and other industrial products. Modifications for different climatic regions. Categories, operating, storage and transportation conditions as to environment climatic aspects influence
GOST 24856-1981 Industrial pipeline fittings. Terms and definitions
GOST 9544-1993 Pipeline gate valves-rates of gates sealibility*， 1993-04-19 Update