Abstract: A turbomachinery rotor blade is provided having an aerofoil body, and a hole penetrating the aerofoil body from a suction surface to a pressure surface thereof. The hole is suitable to receive a lacing wire. The blade further has a protrusion from the suction or pressure surface. The protrusion extends in a downstream direction from a downstream side of the hole and/or extends in an upstream direction from an upstream side of the hole, thereby disturbing the suction or pressure surface to locally thicken the aerofoil body adjacent the hole. The maximum radial extent of the protrusion in the radially outward direction of the blade is radially coterminous with the outboard side of the hole, and the maximum radial extent of the protrusion in the radially inward direction of the blade is radially coterminous with the inboard side of the hole.

Abstract: A turbomachinery rotor blade is provided having an aerofoil body, and a hole penetrating the aerofoil body from a suction surface to a pressure surface thereof. The hole is suitable to receive a lacing wire. The blade further has a protrusion from the suction or pressure surface. The protrusion extends in a downstream direction from a downstream side of the hole and/or extends in an upstream direction from an upstream side of the hole, thereby disturbing the suction or pressure surface to locally thicken the aerofoil body adjacent the hole. The maximum radial extent of the protrusion in the radially outward direction of the blade is radially coterminous with the outboard side of the hole, and the maximum radial extent of the protrusion in the radially inward direction of the blade is radially coterminous with the inboard side of the hole.

Abstract: A connector for connecting an impeller to a shaft is provided. The connector is formed as a unitary body. The connector has a sleeve portion which is frictionally connected on a radially outer surface of a shaft-side hub extension of the impeller. The connector further has a threaded portion carrying a thread which screws onto a corresponding threaded portion of the shaft, such that the connector provides a rotationally fixed connection between the impeller and the shaft. The hub extension has a central recess, and a part of the connector is inserted into the recess. The frictional connection between the sleeve portion and the radially outer surface of the hub extension transmits, in use, substantially all of the torque between the shaft and the impeller.

Abstract: A connector for connecting an impeller to a shaft is provided. The impeller has a shaft-side hub extension with a central recess. The impeller is formed of a material having a greater coefficient of thermal expansion than the material of the shaft. The connector is inserted into the recess to frictionally connect an outwardly facing surface of the connector with a radially inner surface of the hub extension. The connector has a threaded portion carrying a thread which screws onto a corresponding threaded portion of the shaft, such that the connector provides a rotationally fixed connection between the impeller and the shaft. The connector is formed of a material having a coefficient of thermal expansion which is greater than the coefficient of thermal expansion of the material of the shaft.

Abstract: A connector for connecting an impeller to a shaft is provided. The connector is formed as a unitary body. The connector has a sleeve portion which is frictionally connected on a radially outer surface of a shaft-side hub extension of the impeller. The connector further has a threaded portion carrying a thread which screws onto a corresponding threaded portion of the shaft, such that the connector provides a rotationally fixed connection between the impeller and the shaft. The hub extension has a central recess, and a part of the connector is inserted into the recess. The frictional connection between the sleeve portion and the radially outer surface of the hub extension transmits, in use, substantially all of the torque between the shaft and the impeller.