SCROLL CASING FOR EXHAUST GASES OF GAS TURBINE ENGINE

摘要

FIELD: engines and pumps.;SUBSTANCE: invention relates to structures of aircraft gas turbine engines, in particular, to structures of units for removal of hot gases, and can be used in gas pumping units – GPUs or power plants based on a gas turbine engine – GTE. Aim of the invention: increasing the cyclic strength and resource of the scroll casing. To achieve this aim, a scroll casing for exhaust gases of a gas turbine engine is used, it comprises a housing with front, rear and side walls, an axial diffuser located between the front and rear walls of the housing, having a cavity for accommodating an output node of a gas turbine engine in it, and also containing inner and outer shell with flanges, while in the scroll casing each of the flanges of the inner and outer shells of the diffuser is made composite in the form of a ring and an annular shell interconnected by welding, the flange of the inner shell of the diffuser is made of hollow metal pipe, and the ring of the flange of the outer shell of the diffuser is made of a metal bar of circular cross-section, the annular shells of the flanges of the inner and outer rings of the diffuser are made of sheet metal material, each of them is connected by welding with the corresponding rings of the flanges of the diffuser side flaps, moreover, the fastening of the outer shell with the inner shell of the diffuser is made by welding arcs made of metal bar of circular cross-section, so that the front, rear and side walls are made of inner lining, supporting frame and outer lining, and the ratio of the thickness of the outer and inner casings is δ_1/δ₂ = 2–4, where δ₁ – the thickness of the inner lining, δ₂ – thickness of the outer skin. Further, the bearing frame can be made of shaped steel in the form of stainless heat-resistant profile pipes or rolled steel, made of a bent flat sheet. Said inner shell is made protruding above the upper flange. And the length of the protrusion of the inner shell above the upper flange can be selected in the range L = 220–270 mm. Said internal and external lining can be made of stainless heat-resistant sheet metal. Also, a groove of rectangular cross section can be made in the upper flange, in which the sealing cord is placed.;EFFECT: increased cyclic strength and life of the scroll casing.;6 cl, 5 dwg, 2 tbl