GB697687A - Improvements relating to turbine or compressor rotors - Google Patents

Abstract

697,687. Turbine and compressor rotors. ATKINSON, J. May 7, 1951, No. 10718/51. Addition to 630,395. Class 110(iii) Alternate laminae of laminated rotor bodies for axial flow gas turbines or compressors have their rims provided with spaced recesses which are each shaped to accommodate a tongue on the root of a separately fabricated blade, the recesses being completely overlapped by an unrecessed portion of at least one adjacent lamina. The rotor may comprise five disc-like laminae 1, 2, 3, 4, 5, the laminae 2, 4 having recesses 6 spaced around their peripheries in which the tongues 7 of the blade roots are received. Each tongue is bonded by a metal fusion method, e.g. brazing or soldering, to the walls of the recess 6 containing the tongue and also to the surfaces of the adjacent laminae which overlap the recess. The bonding may extend only over a part of the abutting surfaces of the tongue and rotor body, for example as indicated by the dotted line 10. The blade fixing may be supplemented by pins or rivets 11 which may be hollow for the passage of cooling air. Slots 12 may be made between each blade root in the laminae having unrecessed rims to permit distortion and relieve stresses in the rim at high temperatures. The laminae may decrease in thickness in a radially outward direction as described and claimed in Specification 662,527; as shown in Fig. 4, the rotor comprises three discs of which only the inner, 2, has recesses 6 at the rim to accommodate blade root tongues 7. The cavities 13 may be used to contain a cooling medium as disclosed and claimed in Specification 628,100. In a further embodiment, the rotor comprises five laminae each of which has equidistantly spaced recesses, the discs on alternate laminae being offset relatively to those of other laminae, some blades having three tongues while alternate blades have two tongues: