Positive displacement rotary pumps with improved cooling

摘要

Various rotary pumps are disclosed that are designed to pump viscous fluids or slurries. Often, the seals of such pumps can become over heated. The disclosed pumps include slots disposed in the rotors and/or slots disposed in the openings through which the drive and driven shafts task so that some of the fluid being pumped through the pumping chamber can migrate through the proximal wall of the pump casing to the seal assemblies disposed on the other side of the proximal wall of the pump casing. Thus, the seal assemblies of the pumps are cooled without resorting to the use of a cooling jacket or other cooling mechanism.

主权项

1. A rotary pump comprising:
a casing comprising a proximal wall and an open distal end that is closed by a head to form a pump chamber, the pump chamber accommodating first and second rotors; a drive shaft passing through a first bearing assembly and a proximal drive shaft seal before passing through a first opening in the proximal wall of the casing before being coupled to the first rotor; a driven shaft passing through a second bearing assembly and a proximal driven shaft seal before passing through a second opening in the proximal wall of the casing before being coupled to the second rotor; the first and second rotors each comprise a hub for accommodating the drive and driven shafts respectively, the first and second openings of the casing rotatably accommodating the hubs of the first and second rotors respectively; and the hubs of the first and second rotors each including a slot for permitting fluid to pass from the pump chamber, through the slot and past the proximal wall of the casing before reaching the proximal drive and driven shaft seals respectively.