BALL VALVE (VARIANTS) Russian patent published in 2005 - IPC

FIELD: shutoff fittings, particularly ones built in main pipelines to close working medium flow in wide pressure range.

SUBSTANCE: ball valve comprises housing. Installed in the housing are spherical rotary plug, at least one seat seal installed in bush and spring pressing device. Spring pressing device comprises a number of members arranged so that members having different outer diameters alternate. Outer diameter of smaller member exceeds inner diameter of adjacent one. Ball valve in accordance with invention embodiment comprises spring pressing device made as conical spring. Outer diameter of each next spring coil in coil spring cone apex direction is greater than inner diameter of previous one.

EFFECT: increased ball valve air-tightness in seat area due to improved spring pressing device.

7 cl, 2 dwg