Single volute centrifugal pump with two stage impeller

Abstract

Typical centrifugal pumps by their general definition include a single impeller inside a single pump casing, or volute. Two stage, three stage or more stages of pump casings and impellers may be assembled together to achieve higher pump discharge pressures with one pump suction, one pump casing discharge, with input by one driver. This patent covers an impeller design that incorporates two stages of impeller pumping action by using only one impeller operating inside one casing. This same design herein described could be used for more than two stages of impellers operating inside one casing also and is covered by the design parameters shown in this patent application.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

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STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH FOR DEVELOPMENT

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INCORPORATION-BY-REFERENCE OF MATERIAL SUBMITTED ON A COMPACT DISC

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BACKGROUND OF THE INVENTION

Typical centrifugal pumps by their general definition include a single impeller inside a single pump casing, or volute. Two stage, three stage or more stages of pump casings and impellers may be assembled together to achieve higher pump discharge pressures with one pump suction, one pump casing discharge, with input by one driver. This patent applies to a new and unique arrangement of a single pump impeller operating inside a pump casing that produces a partial effect as if it were a two or more stage pump assembly comprised of two or more separate pump impellers and pump casings.

BRIEF SUMMARY OF THE INVENTION

This patent covers an impeller design that incorporates two stages of impeller pumping action by using only one impeller operating inside one casing. This same design herein described could be used for more than two stages of impellers operating inside one casing also and is covered by the design parameters shown in this patent application.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

The attached drawings listed as Figures show the basic arrangement relationship between the claimed new combination of single centrifugal pump casing and impeller to achieve benefits normally gained in pump pressure from the assembly of two separate pump casings and two separate pump impellers.

Figure One: See Figure one sketch of the general arrangement of the two stage impeller design shown inside the pump casing with an adapter shown on the backside of the pump casing. This figure shows the first and second stage impeller vanes, the pump casing inlet (suction), the pump casing discharge flange (outlet),

Figure Two: This sketch shows the passage from the first to the second stage impeller vanes within the pump casing (volute).

Figure Three: This sketch shows two of the various impeller vane shapes that are included in this patent. There are other variations of impeller vane edge shapes that are included by this patent.

Figure Four: This sketch shows a variation of the inlet angle (pump casing suction) to the pump first stage vanes. Straight or any angle of this inlet relationship is covered by this patent.

Figure Five: This sketch shows the first and second stage impeller vanes in staggered design. There maybe any combination of number of impeller vanes, and in any offset degrees as can be built to achieve various flow rates, pressure increases, and best efficiency design of the impeller.

Figure Six: This sketch shows the first and second stage impeller vanes in inline configuration. There may be any number of impeller vanes as can be built to achieve various flow rates, pressure increases, and best efficiency design of the impeller.

Figure Seven: This sketch shows the pump impeller only without the pump casing (volute) or other pump components. The impeller includes an impeller hub of diameter 7.C, a first stage set of impeller vanes of diameter 7.B and a vane height of 7.F, a second stage set of impeller vanes of diameter 7.A and a vane height of 7.D. The total design of the impeller includes back pump out vanes on the top (or back) side of the impeller shroud. This height total then becomes the total height of the impeller vane and shroud.

Figure Eight: Sheet One of Two: This sketch shows an example of this patented impeller design as an enclosed two stage impeller. With an enclosed impeller design there are impeller top 8.B and bottom 8.C shrouds.

Figure Eight: Sheet Two of Two: There are openings 8.i in the bottom shroud of the second stage of the impeller to allow for the flow of the pumped fluid 8.H from the outlet of the first stage impeller vanes into the second stage set of impeller vanes.

DETAILED DESCRIPTION OF THE INVENTION

This invention relates to the basic arrangement of a centrifugal pump in the purpose of raising fluid pressure from a lower to a higher pressure. In some cases the pump may require the assembly of two or more stages (or sets of impellers) to achieve the required design final pressures.

The two stage centrifugal pump impeller design in this patent takes the combined velocity energy from both the first and the second stage impeller diameters and adds them together minus losses, and achieves a higher impeller second stage impeller velocity than would normally be realized from a single stage impeller at the same speed and diameter would produce.

This invention achieves a partial benefit of increase in a pumped fluid pressure as relates to the two or more stage pump impeller combination but achieved with only one pump casing and one impeller. The ability of this pump arrangement is to introduce a fluid into the eye of the first stage impeller vanes and discharge the fluid from these first stage impeller vanes into a larger diameter set of second stage impeller vanes within one common pump casing (or volute). The flow of fluid from the first set of impeller vanes is introduced into the second set of impeller vanes from the larger diameter area of the first set of impeller vanes into the smaller diameter area of the second set of impeller vanes. This flow of fluid from the first set of impeller vanes into the larger diameter set of impeller vanes is directed by the shape of the single pump casing increasing in diameter to follow the increase in the diameter of the first to second set of impeller vanes. The dimensional relationships shown on the attached figure drawings are not precise, nor are intended to be. The dimensional relationships shown are general only and may be changed and still be covered by this patent. This patent covers the fact that there are two (or more) stages of pumping vanes raising the pressure of the pumped fluid from the suction (inlet) of a centrifugal pump to the outlet (discharge) of the same pump more than would be in a single stage impeller vane arrangement. This patent is not specific on the number of impeller vanes in either the first or the second stages of the impeller, but covers from one vane in each of the two stages to as many as necessary to achieve the best combination of flow, pressure, and efficiency of the pump. The impeller vanes may be staggered (FIG. 5, 5.A) in assembly between the first and second stage or may be in line (FIG. 5, 5.D) with each other. There will be many different dimensional sizes of this patented impeller and casing design. There will be different size combinations based on small to larger flow and pressure requirements. The same two or more stage concept may be used for smaller to larger size pump inlet (suction) and outlet (discharge) combinations.

Claims

1. A centrifugal pump design with one impeller providing the effects of a two stage impeller design operating within one pump casing, FIG. 1.

2. A centrifugal pump impeller with a “step” design which include single stage and second stage impeller vanes as part of one impeller. FIG. 1, (1.G., 1.H)

3. A pump design that incorporates the effects of a single stage impeller raising of pressure along with the added pressure of the pump by a second set of impeller vanes, FIG. 1, (1.G., 1.H.)

4. A single casing (volute) FIG. 1 (1.i) design centrifugal pump that includes a first set of impeller vanes FIG. 2 (2.E) pumping a fluid that flows from the first impeller stage vanes up to and into the inlet FIG. 2 (2.F) of a second stage FIG. 2 (2.B) of impeller vanes within the said one single volute

5. The patented single casing (volute), two or more stage impeller design may be built in various sizes to accommodate various flow, pressure, and efficiencies as required. There is no limit to the number of sizes possible by this design.

6. A centrifugal pump impeller with two sets of impeller vanes such that the diameter of the first stage impeller vanes FIG. 7 (7.B) is smaller than the second stage impeller vanes FIG. 7 (7.A)

7. A centrifugal pump impeller with two sets of impeller vanes such that the sum total of the centrifugal pump discharge pressure realized from the exit flow of the second stage impeller vanes is more than would be measured if the pump impeller consisted of only one set of vanes the same diameter as the claimed second set of impeller vanes in this two stage impeller design and did not include a two stage design set of impeller vanes.

8. A centrifugal pump design with either an open or a closed design impeller set of vanes to achieve a two stage pump effect of raising pressure more than if just a one stage set of impeller vanes are used. The actual pump discharge pressure from this two stage impeller design is more than would be realized from a same single stage impeller of the same diameter as the second stage impeller diameter of this two stage impeller design.