Abstract: A sealing ring for controlling gas leakage through the annular space between two rotating concentric members; for example engine shafts. The sealing ring 20 has a generally trapezoidal cross section and an overlapping scarf joint. The sealing ring improves sealing by providing continuous lines of contact at edges between inner and outer coaxial shaft members.

Abstract: A cooling air pick up for use in a gas turbine engine includes a cooling air duct incorporating a diffuser to maximize the cooling air pressure. The entry orifice of the pick up duct is formed in the leading edge of a flow vane in the interior of a flow passage downstream of the engine compressor section.

Abstract: A rotor assembly for use in a rotodynamic machine comprises a rotor disc (10) with a plurality of blades (14) attached to its outer rim (12) and a seal plate (22) for substantially preventing the escape of blade cooling air. The rotor disc (10) is provided with a plurality of hooked restraining members (30) each including a radially inward directed abutment face (32) which in use restrain the seal plate from moving axially and from moving radially outward under centrifugal force by abutment with the seal plate. In this way the blades (14) are not subjected to additional loading by the seal plate (22).

Abstract: A stator assembly for a turbomachine having a sealing plate which co-operates with sealing members on an adjacent rotor assembly to form air seals. The sealing plate is provided with a thermal slugging mass, the thermal response of which controls the rate of expansion and contraction of the sealing plate to match that of the rotor. In this way tip clearances between the stationary and rotating parts of the air seals are maintained substantially uniform throughout all operating conditions of the turbomachine.