Abstract: A bladed rotor arrangement comprises a rotor, a plurality of rotor blades and a plurality of lock plates. The rotor blades are mounted in circumferentially spaced axially extending slots in the periphery of the rotor. A plurality of lock plates are arranged at a first axial end of the rotor and a plurality of lock plates are arranged at a second axial end of the rotor. The radially outer ends of the lock plates engage corresponding grooves defined by radially inwardly extending flanges on the platforms of the rotor blades. The radially inner ends of the lock plates also engage circumferentially extending grooves. The radially inner end of each lock plate has three crushable, deformable, circumferentially spaced feet to reduce the risk of the lock plates chocking against the rotor, or seal plates and additional radial loads being reacted by the rotor blades into the rotor.

Abstract: A bladed rotor arrangement comprises a rotor, a plurality of rotor blades and a plurality of lock plates. The rotor blades are mounted in circumferentially spaced axially extending slots in the periphery of the rotor. A plurality of lock plates are arranged at a first axial end of the rotor and a plurality of lock plates are arranged at a second axial end of the rotor. The radially outer ends of the lock plates engage corresponding grooves defined by radially inwardly extending flanges on the platforms of the rotor blades. The radially inner ends of the lock plates also engage circumferentially extending grooves. The radially inner end of each lock plate has three crushable, deformable, circumferentially spaced feet to reduce the risk of the lock plates chocking against the rotor, or seal plates and additional radial loads being reacted by the rotor blades into the rotor.

Abstract: Mounting discs (20, 30, 40, 50) are used in gas turbine engines to present turbine or compressor blades. These discs (20, 30, 40, 50) incorporate a bore or cob end 31, 41, 51 which in turn previously had a flat end face surface. Such flat end face surfaces are weight efficient but can lead to reduced component life and a limitation with regard to rotational speed due to Von-Mises stresses. By providing a deviation (39, 49, 59, 69) in the end face from a flat aspect, a reduction in axial stress is achieved with a marginal increase in hoop stress but with a net result that there is a reduction in the general operational Von-Mises stresses and therefore improvement in disc life or potential rotation speed capacity or both.