Bearing and seal percolator for a centrifugal pump

A percolator system for providing fluid flow to mechanical seals and to bearings supporting a drive shaft, on which is mounted an impeller having pumping vanes and at least a back shroud, disposed within a housing of a centrifugal pump, during intermittent dry running periods, said pump having a discharge nozzle, comprising:

• a chamber having a lower end attached to said discharge nozzle and an upper end attached to a discharge pipe, said chamber having an inside diameter greater than an outside diameter of said discharge, and said chamber further having an internal percolator pipe at least equal in diameter to the discharge and extending from said discharge to a height less than the height of the chamber such that fluid coming from said nozzle discharge overflows into the chamber;
• a fluid return port near the lower end of said chamber and having one end of a return tube attached thereto;
• an external injection connection on the pump housing for receiving a second end of said return tube;
• means within said housing for conducting fluid from said injection connection to said bearings and seals;
• and
• means for pumping said fluid from said bearings and seals to a torus surrounding said impeller.