GB666911A - Improvements in or relating to diaphragms for impulse turbines - Google Patents

Abstract

666,911. Turbines. YATES, H. G., and PARSONS & MARINE ENGINEERING TURBINE RESEARCH & DEVELOPMENT ASSOCIATION. Feb. 3, 1950. [June 7, 1949] No. 15167/49. Class 110(iii). In a diaphragm for an impulse turbine, the part thereof in which the steam or gas channels are accommodated is separate from the casing k and comprises a number of segments which are inserted in an annular groove in the inner face of the casing, the segments being so secured thereto as to prevent bending about axes tangential to the diaphragm periphery and lying in the plane of the diaphragm, and freedom for relative radial expansion between the part accommodating the steam or gas channels and the diaphragm h being provided at the inner periphery of the said part. The nozzles are built up of division plates d separated by packing pieces a, the division plates being secured in an inner shroud band b. The packing pieces are secured to the casing by means of serrated edges e and soft caulking pieces f. The inner shroud band b has a groove g within which a peripheral ridge on the diaphragm is a loose fit, a number of radial keys or pins i being provided to maintain the diaphragm concentric with the casing. In a second embodiment, the steam or gas flow annulus is formed of a number of separate nozzle segments each having a steam or gas channel machined therein and the nozzle segments are secured in the casing in the same manner as reaction blading of the integral root type. Specification 617.475 is referred to.