Centrifugal pump apparatus

Claim 2

A high speed centrifugal pump apparatus comprising: a pump case having inlet flow passage means for communication of liquid from a suction line and outlet flow passage means for communication of liquid to a discharge line; a pump shaft mounted for rotational movement within said pump case; an impeller mounted concentrically on said shaft for rotational movement therewith within said pump case, said impeller having a center eye portion on at least one side thereof in communication with said inlet flow passage means, said impeller extending generally radially outward from said pump shaft and having a plurality of vanes projecting laterally from at least one side thereof and extending longitudinally from said center eye portion to its peripheral edge in communication with said outlet flow passage means, each said vane having a varying angle of inclination with respect to the side of the impeller and being curved longitudinally thereby providing a continuous helical surface for moving the liquid without undue shock from said inlet flow passage means to said outlet flow passage means; inducer means in communication with said inlet flow passage means and adapted for rotation with said pump shaft, said inducer means having at least one spiral blade winding concentrically about said shaft in the direction of rotation of said vanes and terminating adjacent the beginning of said vanes at said center eye portion of said impeller whereby said inducer means causes the liquid to accelerate in a direction toward said vanes and maintain a positive pressure against the helical surfaces thereof during high speed rotation of the impeller said inducer means separate from said impeller; and vanes are provided on each side of said impeller and separate inducer means are provided on each side of said impeller including at least one blade terminating adjacent the beginning of a set of vanes, said impeller including a shroud associated with each side of said impeller which extends about said inducer means.

Claim 3

The apparatus of claim 1, wherein each said inducer means includes a pair of axially spaced blades, each of which terminates adjacent the beginning of a set of vanes.

Claim 4

The apparatus of claim 1, wherein said vanes on one side of said impeller are staggered with respect to the vanes on the other side of said impeller.

Claim 5

The apparatus of claim 1, wherein said vanes are enclosed by a shroud, said shroud having an axially extending integral cylindrical flange concentric about said inducer means, said flange having means thereon for preventing a freezing of said impeller with respect to said pump case when the rotation of said impeller stops.

Claim 6

The apparatus of claim 1, wherein said impeller and said pump case are titanium.

Claim 7

The apparatus of claim 1, wherein the pitch of said inducer blade is adapted to accelerate the liquid both in a direction toward said vanes and in a direction corresponding to the direction of rotation of said vanes.

Claim 8

In a high speed centrifugal pump apparatus including a radially split pump case, a pump shaft extending axially within said pump case and adapted for high speed rotation therein, and an enclosed impeller with Francis type vanes on each side thereof mounted to said pump shaft for rotation therewith within said pump case, said pump case having a divided inlet flow passage for communicating liquid to each side of said impeller and an outlet flow passage with two volutes extending about the periphery of the impeller for receiving the discharge of liquid therefrom, said vanes extending substantially from the center eye portions at each side of the impeller to the impeller periphery and adapted to move liquid from the inlet flow passage to the volutes thereby imparting energy to the liquid, the improvement which comprises: inducer means on each side of said impeller proximate the center eye portion thereof for maintaining a positive pressure on said vanes, each said inducer means including at least one spiral blade extending radially substantially between said pump shaft and the axially extending shroud flange in said enclosed impeller, said blade winding concentrically from a leading edge in communication with said inlet flow passage about said pump shaft and terminating adjacent said vanes at said center eye portion, and means for operably connecting said blade to said pump shaft for rotation therewith whereby rotation of said blade causes the liquid from said inlet flow passage to move toward said vanes.

Claim 9

In a high speed centrifugal pump apparatus including a radially split pump case, a pump shaft extending axially within said pump case and adapted for high speed rotation therein, and an enclosed impeller with Francis type vanes on each side thereof mounted to said pump shaft for rotation therewith within said pump case, said pump case having a divided inlet flow passage for communicating liquid to each side of said impeller and an outlet flow passage with two volutes extending about the periphery of the impeller for receiving the discharge of liquid therefrom, said vanes extending substantially from the center eye portions at each side of the impeller to the impeller periphery and adapted to move liquid from the inlet flow passage to the volutes thereby imparting energy to the liquid, the improvement which comprises: inducer means on each side of said impeller proximate the center eye portion thereof for maintaining a positive pressure on said vanes, each said inducer means including at least one spiral blade extending radially substantially between said pump shaft and the axially extending shroud flange in said enclosed impeller, said blade winding concentrically from a leading edge in communication with said inlet flow passage about said pump shaft and terminating adjacent said vanes at said center eye portion, and means for operably connecting said blade to said pump shaft for rotation therewith whereby rotation of said blade causes the liquid from said inlet flow passage to move toward said vanes.

Claim 10

The apparatus of claim 7, wherein said pump case and said impeller are each cast of titanium.

Claim 11

The apparatus of claim 7, wherein the vanes on one side of said impeller are staggered with respect to the vanes on the other side of said impeller.

Claim 12

The apparatus of claim 7, wherein each said inducer means includes a pair of axially spaced blades, each said blade winding concentrically about said pump shaft in the direction of rotation of said impeller.

Claim 13

The apparatus of claim 7, wherein a wearing ring is secured to said pump case concentrically about each said shroud flange and adjacent thereto, said exterior surface of said shroud flanges and said interior surfaces of said wearing rings being provided with oppositely oriented spiral grooves to prevent said wearing rings and said shrouds from freezing together.

Claim 14

A single stage high speed, high capacity centrifugal pump apparatus comprising: a split pump case having an integrally cast body member and an integrally cast insert member, said body member having an axially extending bore enlarged at one end, said insert member extending partially into the enlarged portion of said bore and having an axially extending bore in concentric parallel alignment with the other portion of said body member bore thereby providing a continuous axially extending bore through said pump case, said body member and said insert member being sealably joined alonG an annular radially extending surface and forming within said pump case an impeller chamber between the inwardly extending end of said insert member and the end of the enlarged portion of said body member bore; a pump shaft extending through said pump case bore and mounted for rotational movement therein; an impeller member mounted concentrically on said pump shaft for rotational movement therewith within said impeller chamber, said impeller member having a central wall which tapers radially outward to its periphery from center eye portions on each side thereof adjacent said pump shaft, said generally radially extending sides of said central wall being symmetrical concave surfaces of revolution about said pump shaft, adjacent each said side of said center wall and spaced therefrom a shroud having an integral cylindrical flange extending axially about said pump shaft and concentric therewith; inlet flow passage means formed within said pump case by said body member and said insert member for communication of liquid from a suction line, said inlet flow passage means having a pair of channels for communication of the liquid to each of said center eye portions; outlet flow passage means formed within said pump case by said body member and said insert member for communication of liquid to a discharge line, said outlet flow passage means having a pair of volute passages extending about the periphery of said impeller, each said volute passage having an opening for receiving discharge flow from the impeller with said openings being substantially 180* apart; a set of vanes on each side of said impeller member center wall extending laterally from said side to said shroud and extending longitudinally from a center eye portion thereof to the impeller periphery, each said vane having a varying angle of inclination with respect to said sides of said impeller member and being curved longitudinally along its length and thereby providing a continuous helical surface for moving liquid from said center eye portions to said volute openings; and inducer means operably connected to said pump shaft for rotation therewith on each side of said impeller member substantially within the cylindrical flange of said shroud and in communication with said channel of said inlet flow passage means, each said inducer means having at least one spiral blade extending substantially between said shroud and said pump shaft said blade winding from a leading edge concentrically about said pump shaft in the direction of curvature of said vanes and terminating adjacent the beginning of said vanes at said center eye portion whereby said inducer means move the liquid from said channels toward said vanes and maintain a positive pressure on the helical surfaces thereof during high speed operation of the pump.

Claim 15

A single stage high speed, high capacity centrifugal pump apparatus comprising: a split pump case having an integrally cast body member and an integrally cast insert member, said body member having an axially extending bore enlarged at one end, said insert member extending partially into the enlarged portion of said bore and having an axially extending bore in concentric parallel alignment with the other portion of said body member bore thereby providing a continuous axially extending bore through said pump case, said body member and said insert member being sealably joined alonG an annular radially extending surface and forming within said pump case an impeller chamber between the inwardly extending end of said insert member and the end of the enlarged portion of said body member bore; a pump shaft extending through said pump case bore and mounted for rotational movement therein; an impeller member mounted concentrically on said pump shaft for rotational movement therewith within said impeller chamber, said impeller member having a central wall which tapers radially outward to its periphery from center eye portions on each side thereof adjacent said pump shaft, said generally radially extending sides of said central wall being symmetrical concave surfaces of revolution about said pump shaft, adjacent each said side of said center wall and spaced therefrom a shroud having an integral cylindrical flange extending axially about said pump shaft and concentric therewith; inlet flow passage means formed within said pump case by said body member and said insert member for communication of liquid from a suction line, said inlet flow passage means having a pair of channels for communication of the liquid to each of said center eye portions; outlet flow passage means formed within said pump case by said body member and said insert member for communication of liquid to a discharge line, said outlet flow passage means having a pair of volute passages extending about the periphery of said impeller, each said volute passage having an opening for receiving discharge flow from the impeller with said openings being substantially 180* apart; a set of vanes on each side of said impeller member center wall extending laterally from said side to said shroud and extending longitudinally from a center eye portion thereof to the impeller periphery, each said vane having a varying angle of inclination with respect to said sides of said impeller member and being curved longitudinally along its length and thereby providing a continuous helical surface for moving liquid from said center eye portions to said volute openings; and inducer means operably connected to said pump shaft for rotation therewith on each side of said impeller member substantially within the cylindrical flange of said shroud and in communication with said channel of said inlet flow passage means, each said inducer means having at least one spiral blade extending substantially between said shroud and said pump shaft said blade winding from a leading edge concentrically about said pump shaft in the direction of curvature of said vanes and terminating adjacent the beginning of said vanes at said center eye portion whereby said inducer means move the liquid from said channels toward said vanes and maintain a positive pressure on the helical surfaces thereof during high speed operation of the pump.

Claim 16

The apparatus of claim 12, wherein the vanes on one side of said impeller are staggered with respect to the vanes on the other side of said impeller.

Claim 17

The apparatus of claim 12, wherein said leading edge is inclined to provide a cutting angle with respect to the liquid from said channel of about 7- 1/2 *.

Claim 18

The apparatus of claim 12, wherein each said inducer means includes a pair of axially spaced blades.

Claim 19

The apparatus of claim 15, wherein said leading edges of said part of blades are angularly spaced substantially 180* apart.

Claim 20

The apparatus of claim 15, wherein each said leading edge is inclined to provide a cutting angle with respect to the liquid from said channel of about 7- 1/2 *.

Claim 21

The apparatus of claim 12, wherein said body member and said insert member are titanium.

Claim 22

The apparatus of claim 12, wherein said impeller member is integrally cast and is titanium.

Claim 23

The apparatus of claim 12, wherein a wearing ring is secured to said pump case concentrically about each said shroud flange and adjacent thereto, said exterior surface of said shroud flanges and said interior surfaces of said wearing rings beinG provided with oppositely oriented spiral grooves to prevent said wearing rings and said shrouds from freezing together.

Claim 24

The apparatus of claim 12, wherein a mechanical seal is provided at each end of said pump case concentrically about said pump shaft, said mechanical seal having frictionally engaging relatively movable components adapted to provide a seal between said pump shaft and said pump case, and means for communicating liquid discharged from said impeller to said mechanical seal and thereby cooling said components.

Claim 25

The apparatus of claim 12, wherein turbine drive means are provided for driving said pump shaft, and means are provided on said pump shaft for coupling said pump shaft directly to said turbine drive means.

Claim 26

The apparatus of claim 22, wherein said pump shaft is rotatably mounted within bearing assembly means, and means are provided for connecting said bearing assembly means directly to the oil pressure system of said turbine drive means thereby providing lubricant for said bearing assembly means.

Claim 27

The apparatus of claim 22, wherein turbine drive means is adapted to drive said pump shaft at speeds in excess of 20,000 rpm.