SAFETY CUT-OFF VALVE AND CUTTING-OFF ASSEMBLY OF VALVE Russian patent published in 2004 - IPC

FIELD: machine engineering, namely manufacture of fitting used in branches of industry for quick emergent closing of pipelines.

SUBSTANCE: valve includes housing in the form of tube whose inner diameter is equal to inner diameter of pipeline; cutting off assembly having disc closing organ and ring-seat. The last is arranged in plane normal relative to lengthwise axis of tube of housing for dividing housing by inlet and outlet ducts. Rotary shaft is joined with disc closing organ. Rotary shaft is provided with actuating mechanism. Width of ring of seat consists of 2 - 4.5 thickness values of wall of tube housing. Inner surface of ring-seat is in the form of truncated cone whose base is turned to inlet duct. Minimum thickness of ring-seat exceeds thickness half of tube of housing. Disc closing organ is rigidly joined with rotary shaft by means of angular joint, is has diametrically arranged rubber seal and it rests in closed position upon inner surface of ring-seat without brackets. When said organ is fully open it is arranged along axis of tube of housing. Axis of rotary shaft is spaced by distance equal to 1 - 1.5 thickness values of ring-seat from axial plane of housing tube and from plane of contact of disc closing organ with inner surface of ring-seat. Actuating mechanism provides turning of rotary shaft by angle (88 +- 2) degrees. Cutting off assembly includes disc closing organ and ring-seat. The last divides inner cavity of cylindrical housing by inlet and outlet ducts and it has inner surface in the form of truncated cone whose base is turned to inlet duct. Disc closing organ includes round plate and annular seal fastened along periphery of closing organ by means of washer. In closed state disc closing organ rests upon inner surface of ring-seat at side of inlet duct. Width of ring-seat consists of 2- 4.5 thickness values of wall of pipeline. Apex angle of cone inner cone surface of ring-seat is equal to where - apex angle of cone, degrees; D_s - specific diameter of pipeline, mm. Diameter of base of truncated cone is no more than (D_t-0.5•S) where D_t - inner diameter of tube of housing, mm; S - thickness of wall of tube of housing, mm.

EFFECT: increased rate of valve operation at emergent closing of pipeline, lowered hydraulic resistance, improved manufacturability of valve due to lowered number of assortment of parts.

2 cl, 4 dwg