STEAM TURBINE QUICK-ACTING CLACK VALVE Russian patent published in 2003 - IPC

FIELD: mechanical engineering; steam turbines. SUBSTANCE: proposed quick acting clack valve has body, seat plate suspended on lever from drive shaft in body. Novelty is provision of seal containing cup made of fluoroplastic and provided with trapezoidal groove. Groove is made symmetrically relative to other and inner diameters of cup forming two walls with angle of inclination at apex of trapezium from 4^° to 10^°. Seal contains spacer ring with trapezoidal working part getting into groove. Seal is provided with flange and spring installed between flange and spacer ring. Distance ring made of floroplastic can be installed between spring and spacer ring. Spacer ring is cut into sectors. Clearance is left between end faces of sectors to provide radial displacement of sectors and tight fitting of both walls of cup to surfaces of drive shaft and body bore. Split ring can be made of fluoroplastic. EFFECT: provision of reliable sealing of drive shaft, increased service life of clack valve and low friction coefficient. 3 cl, 2 dwg