| 摘要 |
A cantilever shaft centrifugal pump including a volute casing and impeller within said casing and mounted on the end of the cantilever shaft. The volute chamber has an inlet coaxial with the axis of the cantilever shaft and an outlet extending tangentially of the wall of said volute casing. The impeller is of the shrouded type having spaced front and rear shrouds opening at the periphery of said shrouds with impeller vanes therebetween. The outer walls of the front and rear shrouds conform to arcs struck from the center of the bearings for the shaft, and the walls of the pumping chamber have clearance with the walls of the front and rear shrouds along arcs struck from the same center as the center of the walls of the front and rear shrouds. This accommodates radial excursions of the impeller and shaft upon large radial thrusts on the impeller and avoids catastrophic contact between the shrouds of the impeller and the stationary surfaces of the pumping chamber. The pumping chamber is sealed by mechanical seals having mating arcuate sealing faces extending about the cantilever drive shaft for the impeller, to accommodate free radial excursions of the shaft and impeller relative to the pump casing upon high thrust conditions without leakage along the cantilever drive shaft for the impeller.
|
