A cutting blade assembly establishes a bidirectional and/or multifaceted scissor-type cutting action to efficiently and effectively process various types of debris encountered by the cutting blade assembly. The assembly includes a cutting plate and a cutting hub configured for relative rotation. A cutting slot is formed in the cutting plate and intersects the axial face to define a cutting edge at the intersection of the cutting slot and the axial face. The cutting hub has a cutting arm positioned adjacent to the axial face. When the cutting plate and the cutting hub undergo relative rotation, the cutting arm passes adjacent to the cutting edge to perform a scissor-type cutting action.

A stator for a helical gear device includes a first section having first helically convoluted chamber with a set of radially inwardly extending lobes and a second section adjacent to the first section. The second section includes a stack of cutter disks. Each cutter disk includes a front surface, a rear surface, an interior surface defining a central opening extending from the front surface to the rear surface, a forward cutting edge, and a rearward cutting edge. The interior surface forms a same number of lobes for the central opening as the set of radially inwardly extending lobes in the first section. Each cutter disk is aligned along a common centerline, and each cutter disk is rotated slightly relative to each other to form a second helically convoluted chamber with a same pitch as the first helically convoluted chamber. The second helically convoluted chamber exposes, to materials passing through, portions of the forward cutting edge or the rearward cutting edge of each cutter disk.

A well tool assembly, system, and method for handling well debris is described. The assembly includes an electric submersible pump (ESP) configured to be positioned within a wellbore and a well debris cutting tool configured to be positioned downhole relative to the ESP within the wellbore. The ESP is configured to rotate in a first direction to pump well fluid in an uphole direction. The well debris cutting tool is configured to rotate in a second direction opposite the first direction and to grind debris carried by the well fluid in the uphole direction.

The purpose of the present invention is to provide a pump device that has a function to separate foreign matter from a working fluid in which foreign matter is mixed and that is capable of supporting a large working fluid flow rate. The present invention includes a first pump that is provided above a working fluid reservoir, and a second pump that has a rotary shaft that is concentric with a rotary shaft of the first pump and that is provided further down than an inlet of the first pump. A centrifuge filtration device having functionality to separate foreign matter from the working fluid is provided in an area below the inlet of the first pump and above the second pump, and the centrifuge filtration device is disposed so that the inner diameter on the second pump side is large and the inner diameter on the first pump side is small.

A cutting blade assembly establishes a bidirectional and/or multifaceted scissor-type cutting action to efficiently and effectively process various types of debris encountered by the cutting blade assembly. The assembly includes a cutting plate and a cutting hub configured for relative rotation. A cutting slot is formed in the cutting plate and intersects the axial face to define a cutting edge at the intersection of the cutting slot and the axial face. The cutting hub has a cutting arm positioned adjacent to the axial face. When the cutting plate and the cutting hub undergo relative rotation, the cutting arm passes adjacent to the cutting edge to perform a scissor-type cutting action.

A stator for a helical gear device includes a first section having first helically convoluted chamber with a set of radially inwardly extending lobes and a second section adjacent to the first section. The second section includes a stack of cutter disks. Each cutter disk includes a front surface, a rear surface, an interior surface defining a central opening extending from the front surface to the rear surface, a forward cutting edge, and a rearward cutting edge. The interior surface forms a same number of lobes for the central opening as the set of radially inwardly extending lobes in the first section. Each cutter disk is aligned along a common centerline, and each cutter disk is rotated slightly relative to each other to form a second helically convoluted chamber with a same pitch as the first helically convoluted chamber. The second helically convoluted chamber exposes, to materials passing through, portions of the forward cutting edge or the rearward cutting edge of each cutter disk.

Embodiments of the invention provide a cutting assembly for a chopper pump. The cutting assembly includes a cutting insert having a cutting blade extending radially therefrom, and an impeller having a central hub, a plurality of vanes, and an insert surface. The insert surface defines an axial recess that is dimensioned to receive the cutting insert therein. The cutting assembly further includes a cutting plate having a plate hub with a cutting extension protruding radially inward therefrom. Rotation of the impeller rotates the cutting blade past the cutting extension.

A centrifugal pump that is used for conveying water and other fluids. The pump is constructed such that the movement of water is provided without undue pressures being needed.

A contra-rotating multi-layer propeller unit for multi-phase flow according to an exemplary embodiment of the present disclosure includes: a shaft part; a front propeller and a rear propeller connected to the shaft part; an air collection part including a predetermined space therein and the shaft part positioned in the internal space; and an air supply pipe configured to supply air into the air collection part, and a rear propeller blade includes a two-phase blade connected to a rear propeller hub, a layer structure of which an inner surface is connected to an end portion of the two-phase blade, and a single-phase blade positioned at a location corresponding to the two-phase blade on an outer surface of the layer structure.

The invention provides a centrifugal pump, distinctive in that the pump comprises two or more stages; the last stage in the direction of flow has been adapted so that it provides a larger equilibrium droplet size than the upstream stages. Method of designing the pump and use of the pump.