CELLULAR PACKING PRIMARILY FOR STEAM TURBINE Russian patent published in 2000 - IPC

FIELD: packing engineering; above-shroud packings for high-pressure cylinders of steam turbines. SUBSTANCE: cellular packing primarily used for steam turbines has shell with cellular inserts installed in stator body (fixed member) around annular packing ridges of shroud of rotor running blades (moving member) with radial clearance between them; shell has annular packing ridges arranged around running-blade shroud with clearance between them larger than radial clearance of packing; cellular inserts are arranged between shell ridges. Cellular insert is driven in shell through depth (h) of 3 to 6 mm chosen during its design proceeding from requirement that shroud ridges should not cut through cellular insert to shell surface. Cellular insert is made of equilateral hexahedral or tetrahedral cells measuring approximately 0.9 mm (where 0.9 m is diameter of circle inscribed in hexahedron or tetrahedron) which are produced by high-temperature soldering of corrugated bands, usually 0.05 mm thick, made of heat-resistant material such as steel KhN78T; bands are either soldered together or to cylindrical surface of shell. Packing is mechanically designed so that labyrinth passages are formed for working fluid by clearances between packing surfaces at minimal possible radial clearance. EFFECT: improved effectiveness of packing. 2 cl, 3 dwg