US4637779A — Two stage medium consistency pulp pumping

Claim 1

Independent Claim 87 words

A method of pumping a suspension having a consistency between about 6-20%, comprising the step of continuously acting upon a suspension to progressively (a) effect initial fluidization of the suspension; (b) effect removal of extreme pre-rotation of the fluidized suspension, and define a definite directional flow angle of the suspension; (c) effect a first fluidizing pumping of the suspension, in a first stage, to pump the suspension directly to a second stage; and (d) effect a second fluidizing centrifugal pumping of the suspension in the second stage.

Claim 2

Independent Claim 87 words

A method of pumping a suspension having a consistency between about 6-20%, comprising the step of continuously acting upon a suspension to progressively (a) effect initial fluidization of the suspension; (b) effect removal of extreme pre-rotation of the fluidized suspension, and define a definite directional flow angle of the suspension; (c) effect a first fluidizing pumping of the suspension, in a first stage, to pump the suspension directly to a second stage; and (d) effect a second fluidizing centrifugal pumping of the suspension in the second stage.

Claim 3

Dependent Claim 51 words

A method as recited in claim 1 wherein during the practice of steps (a)-(c), the suspension is moved with a primary vector in a first dimension, and wherein after the practice of step (d) the suspension is moved with a primary vector in a second dimension perpendicular to the first dimension.

Claim 4

Dependent Claim 49 words

A method as recited in claim 2 comprising the further step, prior to step (a), of storing the suspension is a vessel; and wherein step (a) takes place in the vessel and simultaneously effects movement of suspension out of the vessel with a primary vector in said first dimension.

Claim 5

Dependent Claim 25 words

A method as recited in claim 3 wherein step (b) is practiced by causing a suspension to move past a plurality of stationary guide vanes.

Claim 6

Dependent Claim 19 words

A method as recited in claim 1 wherein the suspension comprises a suspension of finely comminuted cellulosic fibrous material.

Claim 7

Dependent Claim 20 words

A method as recited in claim 1 wherein steps (a)-(c) impart approximately about a 40-foot head at the second stage.

Claim 8

Dependent Claim 120 words

A centrifugal pump for fluent material comprising: a housing having an inlet and an outlet; a shaft mounted for rotation within said housing about an axis of rotation; a first set of vanes mounted to said shaft within said housing adjacent said inlet; a second set of vanes mounted to said shaft within said housing between said first set of vanes and said outlet; a third set of vanes stationarily mounted to said housing between said inlet and said first set of vanes, said third set of vanes comprising means for removing extreme prerotation of fluent material passing therethrough; and means for effecting rotation of said shaft and said first and second sets of vanes with respect to said housing.

Claim 9

Dependent Claim 120 words

A centrifugal pump for fluent material comprising: a housing having an inlet and an outlet; a shaft mounted for rotation within said housing about an axis of rotation; a first set of vanes mounted to said shaft within said housing adjacent said inlet; a second set of vanes mounted to said shaft within said housing between said first set of vanes and said outlet; a third set of vanes stationarily mounted to said housing between said inlet and said first set of vanes, said third set of vanes comprising means for removing extreme prerotation of fluent material passing therethrough; and means for effecting rotation of said shaft and said first and second sets of vanes with respect to said housing.

Claim 10

Dependent Claim 45 words

A pump as recited in claim 7 further comprising a fourth set of vanes mounted to said shaft and disposed outside of said housing, said fourth set of vanes on the opposite side of said third set of vanes from said first set of vanes.

Claim 11

Dependent Claim 37 words

A pump as recited in claim 8 wherein the means for removing extreme pre-rotation of fluent material also defines a definite directional flow angle of the fluent material from the inlet to the first set of vanes.

Claim 12

Dependent Claim 53 words

A pump as recited in claims 9 wherein said housing presents no intervening stationary structure between said first set of vanes and said second set of vanes, and wherein said first set of vanes comprises means for pumping fluent material directly to said second set of vanes, with a primary vector extending axially.

Claim 13

Dependent Claim 58 words

A pump as recited in claim 10 wherein said third set of vanes comprises X vanes, wherein X is a positive integer 4 or greater, and wherein said first set of vanes comprises Y vanes, wherein Y is a positive integer 3 or greater, and wherein X is not equal to Y or an even multiple of Y.

Claim 14

Dependent Claim 37 words

A pump as recited in claim 7 wherein said third set of vanes extends between a hub and a peripheral member, said peripheral member affixed to said housing, and said hub comprising a bearing for said shaft.

Claim 15

Dependent Claim 64 words

A pump as recited in claim 7 wherein said housing comprises first and second parts connected together, said first part including said outlet and containing said second set of vanes therein, and said second part of said housing defining said inlet and containing said first and third set of vanes therein, said third set of vanes operatively rigidly connected to said housing second part.

Claim 16

Dependent Claim 204 words

A two stage centrifugal pump comprising: a housing elongated in a first dimension and having an inlet at one end thereof disposed in line with said first dimension, and having an outlet extending in a second dimension substantially perpendicular to said first dimension; said housing defining a single central cavity extending from said inlet to said outlet; a shaft elongated in said first dimension and mounted for rotation in said housing about an axis extending in said first dimension and substantially concentric with said inlet; a first set of vanes mounted to said shaft for rotation therewith, mounted within said housing adjacent said inlet, and for moving fluent material pumped thereby axially and away from said inlet; and a second set of vanes mounted to said shaft for rotation therewith, mounted within said housing remote from said inlet and having a portion thereof elongated in said second dimension and disposed adjacent said outlet; said housing presenting no intervening stationary structure between said first and second sets of vanes; and a third set of vanes stationarily mounted to said housing between said inlet and said first set of vanes, said third set of vanes comprising means for removing extreme prerotation of fluent material passing therethrough.

Claim 17

Dependent Claim 204 words

A two stage centrifugal pump comprising: a housing elongated in a first dimension and having an inlet at one end thereof disposed in line with said first dimension, and having an outlet extending in a second dimension substantially perpendicular to said first dimension; said housing defining a single central cavity extending from said inlet to said outlet; a shaft elongated in said first dimension and mounted for rotation in said housing about an axis extending in said first dimension and substantially concentric with said inlet; a first set of vanes mounted to said shaft for rotation therewith, mounted within said housing adjacent said inlet, and for moving fluent material pumped thereby axially and away from said inlet; and a second set of vanes mounted to said shaft for rotation therewith, mounted within said housing remote from said inlet and having a portion thereof elongated in said second dimension and disposed adjacent said outlet; said housing presenting no intervening stationary structure between said first and second sets of vanes; and a third set of vanes stationarily mounted to said housing between said inlet and said first set of vanes, said third set of vanes comprising means for removing extreme prerotation of fluent material passing therethrough.

Claim 18

Dependent Claim 45 words

A pump as recited in claim 14 further comprising a fourth set of vanes mounted to said shaft and disposed outside of said housing, said fourth set of vanes on the opposite side of said third set of vanes from said first set of vanes.

Claim 19

Dependent Claim 38 words

A pump as recited in claim 15 wherein the means for removing extreme pre-rotation of fluent material generated also defines a definite directional flow angle of the fluent material from the inlet to the first set of vanes.

Claim 20

Dependent Claim 37 words

A pump as recited in claim 14 wherein said third set of vanes extends between a hub and a peripheral member, said peripheral member affixed to said housing, and said hub comprising a bearing for said shaft.

Claim 21

Dependent Claim 46 words

A pump as recited in claim 15 wherein said housing is operatively connected to a vessel so that said inlet is in communication with an opening in said vessel; and further comprising a suction bell disposed in said vessel opening and immediately adjacent said housing inlet.

Claim 22

Dependent Claim 53 words

A pump as recited in claim 18 wherein said fourth set of vanes extends into the interior of the vessel above the suction bell, and wherein said vanes of said fourth set of vanes are angled so as to draw material from the vessel into the housing inlet upon rotation of said shaft.

Claim 23

Dependent Claim 69 words

A pump as recited in claim 19 wherein said housing comprises first and second housing parts, said first housing part including said outlet and containing said second set of vanes therein, and said second housing part connected between said suction bell and said first housing part, and containing said first and third set of vanes therein, said third set of vanes operatively rigidly connected to said second housing part.

Claim 24

Dependent Claim 58 words

A pump as recited in claim 14 wherein said third set of vanes comprises X vanes, wherein X is a positive integer 4 or greater, and wherein said first set of vanes comprises Y vanes, wherein Y is a positive integer 3 or greater, and wherein X is not equal to Y or an even multiple of Y.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1990-01-19	1990-07-21	1991-01-20	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	1994-01-19	1994-07-21	1995-01-20	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	1998-01-19	1998-07-21	1999-01-20	$7700.00	Window Closed / Lapsed

Two stage medium consistency pulp pumping

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