Abstract: A water ring vacuum pump including a body with end members, an impeller within the body and having extending outwardly from each end a shaft journaled for rotation in a bearing in the adjacent end member. Each shaft is extended by a stub shaft of equal diameter which abuts the impeller shaft in a driving connection within the bearing.

Abstract: A water ring vacuum pump having a body with end members, an impeller in the body and having a shaft which extends through the end members and being journalled for rotation therein. One end member has an inlet and the other an outlet. A port plate is located in each member and adjacent the ends of the blades of the impeller whereby a manifold is formed between each port plate and its adjacent end chamber. The port plates are moveable relative to their adjacent end members by screws or the like passing through the end member, which screws abut the face of the port plate and can act to vary its location relative to the impeller and locking bolts passing through the end member and into threads in the port plate whereby the port plate can be moved away from the impeller. The locking bolts, when the impeller is correctly positioned, acts against the screws or the like which abut the port plate, thus serving to lock the port plate in position.