| 摘要 |
mechanical engineering; shut-off or adjusting fittings for liquid media containing solid particles. SUBSTANCE: proposed ball cock has body, spherical swivel shut-off member and seat with sealing plastic rings. Seats are fitted in inlet and outlet branch pipes. Each has two metal springing tabs located on side of spherical swivel shut-off member; they are made integral with seat for prevention of seizure of spherical swivel shut-off member. Angle alpha is formed by outer surface of tab and plane passing through radius to point of contact of tab and spherical swivel shut-off member. This angle is selected from condition: tgalpha > Kfr., where Kfr. is coefficient of sliding of solid particles over surface of tab. Prior to assembly, sealing plastic rings of seats project above spherical surface of seats running through point of contact of tab and swivel spherical shut-off member by amount of deformation delta necessary for tightness of cock. EFFECT: increased service life of cock due to cleaning of surface of spherical swivel shut-off member; facilitated procedure of manufacture of cock. 3 dwg
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