Coupling joints to interconnect and transmit rotational torque between adjacent impeller bodies in a turbomachine

Abstract

Improved coupling joints configured to interconnect and transmit torque between adjacent impeller bodies in a turbomachine are provided. A plurality of impeller bodies is stacked on a tie bolt. A respective coupling joint is defined by features in adjacent impeller bodies to couple to one another the adjacent impeller bodies. The coupling joint involves a pair of corresponding axially engaging faces and a pair of corresponding radially engaging faces that define a coupling pilot fit. A torque transmitting arrangement is interposed between the axially engaging faces and radially engaging face. The pair of axially engaging faces in operation defines a compressed joint effective to form a seal between the pair of axially engaging faces to inhibit leakage of a process fluid being processed in the compressor section of the turbomachine. This allows elimination of separate seal arrangements, such as otherwise could involve sleeves with O-rings, etc.