GB512606A - Improved method of manufacturing blade drums for radial flow turbines - Google Patents

Abstract

512,606. Making turbines. ALLMANNA SVENSKA ELEKTRISKA AKTIEBOLAGET. Sept. 22, 1938, No. 7441/39. Convention date, Oct. 26, 1937. Divided out of 502,946, [Group XXVI]. [Class 83 (ii)] Turbine blades 6 are mounted in a drumlike fixing device so that recesses 7 may be cut thereon, the blades then being removed and mounted by their recesses on the permanent strengthening rings 8 which act as part fixings for finishing the blade drum. The first fixing device, however, may be used also to hold the blades while the ends are prepared or dovetailed for securing end rings 1 thereon, e.g., by rolling. The recesses 7 may be formed by turning when mounted on a drum holder or by a planing, milling or like operation when mounted on a flat surface, the recesses then locating the blades axially in a holder of which the ring 8 may form a part, while the profile of the shanks is formed and the ends prepared for the end rings. The recesses 7 may have projections 18 to act as distance pieces for separating one blade from the next and may also'have overhanging parts 10 forced over to hold the ring 8. Fig. 7 shows a sectional view of blade through a recessed portion, the section being thickened from 13 at the ends to 17 at the recessed portion instead of having projections 18 there. Fig. 8 shows a view of part of the inside of the ring 8 showing grooves 14 to receive the part 15, Fig. 7, and lateral grooves 16 receiving the material surrounding the recess.