Abstract: Submerged jet nozzles are located at equal distances from the center of a tank containing a quantity of liquid and solids. Some of the nozzles induce flow partly inward and some induce flow partly outward, but all mixers are directed generally in the same circumferential direction. The inward directed nozzles are located close to the bottom of the tank and direct liquid across the central portion of the tank where solids tend to accumulate. Upper nozzles direct flow at least partly outward but in the same circumferential direction as the lower nozzles. The flow from the upper nozzles tends to reflect off the wall of the tank in addition to inducing a rotational flow of substantially the entire body of liquid in the tank.

Abstract: Submerged jet nozzles are located at equal distances from the center of a tank containing a quantity of liquid and solids. Some of the nozzles induce flow partly inward and some induce flow partly outward, but all mixers are directed generally in the same circumferential direction. The inward directed nozzles are located close to the bottom of the tank and direct liquid across the central portion of the tank where solids tend to accumulate. Upper nozzles direct flow at least partly outward but in the same circumferential direction as the lower nozzles. The flow from the upper nozzles tends to reflect off the wall of the tank in addition to inducing a rotational flow of substantially the entire body of liquid in the tank.

Abstract: A centrifugal pump has a bladed impeller rotating in the bowl of the pump casing. The inlet side of the pump bowl is closed by an intake plate. A hub rotated with the impeller extends through the intake plate, generally axially outward from the impeller blades. The hub has an abrupt projection in close cutting relationship with at least a portion of the intake plate as the impeller is rotated.

Abstract: Stationary cutter teeth project axially inward into the bowl of a centrifugal pump and cooperate with edge portions of the pump impeller vanes at the closed side of the pump bowl for chopping solid matter in the material being pumped.

Abstract: A centrifugal pump has an impeller with vanes including cutting edges at the intake side of the pump bowl. The intake side of the bowl is closed by an intake plate, and an external cutter has blades in close cutting relationship to raised anvil ribs on the intake plate. The intake plate has an outward opening recess including a first portion of one diameter and a second portion of a greater diameter. The external cutter has respective first and second portions closely received in the first and second recess portions, respectively. The first portion of the external cutter cooperates with the first portion of the intake plate recess, and the second portion cooperates with the second recess portion, to chop solid matter entering the pump through the intake plate.

Abstract: A centrifugal pump has an open impeller with vanes having cutting edges at both the intake side of the pump bowl and the closed side of the bowl. The cutting edges of the vanes cooperate with narrow anvil ribs projecting inward from both sides of the pump bowl such that solid matter in the material being pumped is sliced and chopped inside the bowl. In addition, the intake end plate of the pump has an outer depression or recess with raised anvil ribs extending externally outward and cooperating with an additional external cutter received in the recess.

Abstract: The rotary drive shaft of a centrifugal pump extends vertically through a cylindrical housing and into a casing defining a bowl for the impeller of the pump. A mechanical seal and bearings for the drive shaft are positioned between the pump bowl and the interior of the housing which forms a reservoir for liquid lubricant. The impeller includes a radial shroud plate, a first set of pumping blades projecting downward from the shroud plate toward the axial pump inlet and a second set of blades or vanes projecting upward from the shroud plate. The upper vanes result in slight suction being generated in the area of the seal tending to draw lubricant from the housing reservoir through the bearings and seal. Seal failure is detected by a rapid decrease in the level of lubricant in the reservoir.

Abstract: A booster propeller is located at the inlet of a flared funnel leading toward arcuate inlet apertures in an end plate of a centrifugal pump casing. Such propeller has radially projecting blades of generally right triangular cross section with bases formed of the broad trailing sides and broad bottom sides remote from the impeller; the hypotenuse side of each blade being a broad upper surface inclined relative to a plane perpendicular to the axis for propelling slurry toward the inlet apertures. The end plate is recessed into the impeller-receiving bowl of the pump casing such that the inner face of the end plate is flush with the adjoining inner face of the peripheral pump outlet conduit integral with the pump casing. The impeller has a circular shroud plate perpendicular to the axis with vanes or blades projecting toward the end plate and having cupped leading surfaces forming a sharpened edge.

Abstract: The face seal of a centrifugal pump has a stationary seal component mounted on the pump casing and a rotary seal component rotatable with the drive shaft extending into the casing and connected to the inner rotary pumping member or impeller. The rotary seal component is biased against the stationary seal component by a resilient welded metal bellows assembly having its end portion opposite the rotary seal component clamped to the drive shaft. To protect the welded metal bellows assembly against abrasive life-shortening contact with particulates in the liquid being pumped, a rigid shroud is provided including a generally cylindrical cavity having an inner wall portion extending close alongside the bellows for at least substantially the full axial extent of the bellows.