RU2482333C1 - Stage of centrifugal multi-stage pump of open type - Google Patents

Abstract

FIELD: engines and pumps.

SUBSTANCE: stage includes impeller and guiding device. There are additional vanes mounted on guiding device from the side of open edges of impeller blades. Stage flowing channel is equipped with vortex breakers that are made in the form of annular bosses in stage flowing channel or in the form of supporting washes mounted in annular bores of impeller blades and vanes of guiding devices. Annular boss in flowing channel of impeller of minimal diameter is made in the form of axial support of impeller and is equipped with radial channels.

EFFECT: increase of stage pressure and efficiency coefficient.

4 cl, 4 dwg

Description

The invention relates to centrifugal multistage pumps and can be used for oil, water and other fluids from wells.

Known stages of centrifugal multistage pumps, including a directing apparatus and an open impeller according to the book: Bogdanov A.A. Submersible centrifugal electric pumps for oil production (calculation and design). Publishing house "NEDRA", Moscow 1968, pp. 110-122.

The main disadvantage of these steps is that there are gaps between the lower and upper edges of the blades and the disks of the guide vanes. As a result of the gaps, due to the pressure difference at the inlet of the pumped liquid into the impeller and the exit from it, fluid circulation is created. This leads to a decrease in the head pressure and efficiency.

The closest in technical essence to the invention is the step of a submersible centrifugal multistage pump, known according to patent RU 2209345 C2, IPC ⁶ F04D 13/10, F04D 31/00 from 06.22.2001, including a guiding apparatus and an open impeller with vanes on the bottom surface drive disk. The main disadvantage of this step is that there is a gap of at least 2 mm between the lower edge of the blades and the upper surface of the upper disk of the guide vane. The pressure of the pumped liquid at the outlet of the impeller is higher than the pressure at the inlet to it, and part of the liquid in the gap along the surface of the disk returns to the inlet. Then this liquid is again pumped to the exit. This creates a vortex fluid motion. The thickness of the vortex depends on the size of the gap and can cover a significant area of the blades, plugging the passage section of the channel of the impeller. This leads to a decrease in stage pressure and efficiency.

The objective of the invention is to obtain a technical result, which is expressed in increasing the pressure and efficiency of a centrifugal multistage open-type pump stage.

The indicated problem in the design of a stage of an open-type centrifugal multistage pump containing an impeller and a directing apparatus is solved by the fact that auxiliary blades are installed on the directing edges of the impeller blades on the directing apparatus, and the flow channel of the stage is equipped with vortex shredders, which are made in the form of ring protrusions in the flow channel of the stage or in the form of supporting washers installed in the annular grooves of the blades of the impellers and vanes of the guide vanes, and the ring protrusion in the flow channel of the impeller of smallest diameter is formed as an axial support of the impeller and is provided with radial channels.

The scientific and technical analysis of the proposal and the level of technology indicates that the proposed technical solution for a specialist does not follow explicitly from the prior art, while the features of the set described above are interconnected, are causally related to the expected result, and are necessary and sufficient for it receipt.

The invention is illustrated by drawings, where:

figure 1 shows a variant of the stage of an open-type centrifugal multistage pump with a vortex grinder in the form of ring protrusions;

figure 2 shows a variant of the stage of an open-type centrifugal multistage pump with a vortex grinder in the form of support washers;

figure 3 shows a variant of the stage of an open type centrifugal multistage pump with auxiliary vanes mounted on the guide apparatus from the open edges of the impeller vanes;

figure 4 shows a variant of the stage of an open-type centrifugal multistage pump with an annular protrusion made in the form of an axial support of the impeller.

The step variant (see FIG. 1) comprises an open guide apparatus 1 and an open impeller 2 mounted on the shaft 3. In the flow channel of the step, vortex shredders are made in the form of annular protrusions, for example, 4, 5, 6. During rotation of the shaft 3 with the impeller 2 creates a pressure difference of the pumped liquid at the entrance to the impeller 2 and its output, as well as at the entrance to the guide apparatus 1 and its output. In this regard, the pumped liquid (shown by the dashed line) from the input of the impeller 2 enters (shown by arrows) to its output, and then to the input of the guide apparatus 1 and then to its output. Since the pressure at the outlet of the impeller 2 is higher than at its inlet, part of the liquid tends to return to the inlet due to the presence of a gap between the open edge of the blade and the wall associated with it. In this case, the liquid bumps onto the annular protrusions 4 and 5. As a result, instead of one large vortex, two small vortices 7 appear (shown by the dashed line). The number and size of vortices depends on the number of annular protrusions. Less vortices are used to generate less energy. Moreover, smaller vortices to a lesser extent overlap the flow channel of the stage. This leads to an increase in the pressure and efficiency of the stage. A similar process takes place in the guide apparatus 1.

Shredders of vortices can be made in the form of supporting washers 8 installed in the annular grooves of the blades of the impellers 2 or the blades of the guide vanes 1 (Fig.2). Washers 8 can also serve as axial bearings of the impeller 2.

An increase in pressure is also facilitated by auxiliary blades 9 (see FIG. 3) on the guide apparatus 1 mounted on the side of the open edges of the impeller blades. Possessing kinetic energy, the part of the liquid 10, unwound in the flow channel of the impeller 2, hits the auxiliary blades 9 and loses kinetic energy, which is converted into pressure energy. As a result, the pressure created by the impeller 2 increases.

An annular protrusion 4 in the flow channel of the smallest impeller 2 (see FIG. 4) can be made in the form of an axial support of the impeller 2 and have radial channels 11 for the passage of the pumped liquid.

Thus, the invention allows to obtain a technical result, expressed in increasing the pressure and efficiency of the centrifugal multistage open-type pump stage.

Claims (4)

1. The stage of an open-type centrifugal multistage pump, comprising an impeller and a guiding apparatus, characterized in that auxiliary vanes are installed on the guiding apparatus on the side of the open edges of the impeller blades, and the flow channel of the stage is equipped with vortex shredders. 2. The stage of a centrifugal multistage pump according to claim 1, characterized in that the vortex shredders are made in the form of annular protrusions in the flow channel of the stage. 3. The centrifugal multistage pump stage according to claim 1, characterized in that the vortex shredders are made in the form of supporting washers installed in the annular grooves of the impeller blades and vanes of the guide vanes. 4. The stage of a centrifugal multistage pump according to claim 2, characterized in that the annular protrusion in the flow channel of the smallest impeller is made in the form of an axial support of the impeller and is provided with radial channels.

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