CN220168229U - Flow guiding device of multistage pump - Google Patents

Abstract

The utility model provides a flow guiding device of a multistage pump, which comprises a plurality of axial guide vanes arranged at the tail end of a flow channel and a plurality of anti-guide vanes connected with an annular space outlet at the middle section of the flow channel; and the annular space is connected with the flow channel outlet of the primary impeller close to the incoming flow direction. By adding the flow guiding device at the outlet of the back guide vane of the multi-stage pump, the water flow tends to enter the secondary impeller axially due to the action of the double guide vanes, and the circumferential velocity component of the water flow is reduced. The guide device is reasonably added at the outlet of the back guide vane of the multistage pump, so that the liquid rotation component is eliminated, and meanwhile, the liquid is introduced into the lower impeller; the flow state distribution of the inlet of the secondary impeller is more uniform, vortexes which possibly occur are avoided, the loss in the flowing process is reduced, and the overall hydraulic efficiency of the multistage pump is improved.

Description

Flow guiding device of multistage pump

Technical Field

The utility model relates to the technical field of connection and flow guiding of multistage pumps, in particular to a flow guiding device of a multistage pump.

Background

For the multistage pump, when liquid flows out from the rotation of the first-stage impeller, the rotation component of the liquid is larger, the liquid enters the back guide vane along the annular space, the flow speed is reduced, the rotation component of the liquid is eliminated, and the effect of introducing the liquid into the lower-stage impeller is also achieved. However, when the specific rotation speed of the centrifugal pump is lower, the rotation component of liquid cannot be well eliminated by the back guide vane, the circumferential velocity component of the outlet is larger than the axial velocity, the flow state in the back guide vane directly influences the flow field distribution of the secondary impeller, so that the inlet of the secondary impeller generates high-speed rotating water flow, and certain flow loss is necessarily generated in the process, so that the difference of the work applied by the secondary impeller compared with that of the primary impeller is obvious. Therefore, it is necessary to adjust the flow pattern of the outlet of the back guide vane to accommodate the secondary impeller, so that the flow pattern entering the secondary impeller is more uniform, and the loss in the flow process is reduced.

Prior art CN215171029U a section multistage pump impeller, discloses a section multistage pump impeller, including preceding stage impeller, preceding stage impeller one side fixedly connected with rear stage impeller, be provided with the stator wheel main part between preceding stage impeller and the rear stage impeller, the stator wheel main part includes positive stator, semi-circular space stator, stator fixed plate, back guide and stator wheel mounting panel, positive stator fixed connection is at the side end face of stator fixed plate one side, semi-circular space stator fixed connection is at the one end of positive stator, back guide fixed connection is at the one side that the stator fixed plate deviates from positive stator, stator wheel mounting panel fixed connection is at back guide and deviates from stator fixed plate one side. The problem in the prior art is that the semicircular space guide vane is complex to manufacture and form, and only plays a role in guiding flow between the front guide vane and the back guide vane, so that the rotation component cannot be eliminated, and liquid is introduced into the lower-stage impeller.

Disclosure of Invention

In order to solve the problems in the prior art, the utility model provides a flow guiding device of a multistage pump, which comprises a plurality of axial guide vanes of an annular pipe arranged at the tail end of a flow passage and a plurality of reverse guide vanes connected with an annular space outlet at the middle section of the flow passage; the runner initial section is an annular space for connecting the first-stage impeller and the runner outlet of the first-stage impeller. By adding the flow guiding device at the outlet of the back guide vane of the multi-stage pump, the water flow tends to enter the secondary impeller axially due to the action of the double guide vanes, and the circumferential velocity component of the water flow is reduced. The guide structure is reasonably added at the outlet of the back guide vane of the multistage pump, so that the liquid rotation component is eliminated, and meanwhile, the liquid is introduced into the lower impeller; the flow state distribution of the inlet of the secondary impeller is more uniform, vortexes which possibly occur are avoided, the loss in the flowing process is reduced, and the overall hydraulic efficiency of the multistage pump is improved.

Preferably, the bone line of the axial guide vane is a section of circular arc, and the thickness of the axial guide vane is 2-3 mm. The whole shape of the axial guide vane needs to have a guiding effect on the liquid introduced into the lower-stage impeller, and meanwhile, the time of cavitation and other phenomena caused by metal fatigue when the axial guide vane works for a long time is prolonged, and the service life of the axial guide vane is prolonged.

Preferably, the bone wire ends are perpendicular to the outlet edge of the annular tube ends. The bone line end is perpendicular to the outlet edge of the annular tube end, namely, liquid tends to be axially introduced into the secondary impeller, so that the circumferential velocity component of the secondary impeller is reduced, possible vortex is avoided, and the loss in the flowing process is reduced.

Preferably, the included angle between the tangent line of the starting point of the bone line and the inlet edge of the annular tube is 45-65 degrees. When the axial guide vane is in drainage work, the starting point of the bone line is a drainage end, the included angle between the drainage end and the inlet edge of the annular tube is 45-65 degrees, the flow state of liquid in the flow channel can be better attached, the loss of the liquid in the flowing process is reduced, and the possible vortex at the drainage end is avoided.

Preferably, the runner of the runner end section is an annular pipe axially parallel to the impeller, and the axial guide vane is arranged on the inner pipe wall of the annular pipe inner ring. Under the condition of low-speed rotation, the axial guide vane is arranged on the inner side pipe wall of the annular pipe inner ring and can drain most liquid.

Preferably, the axial guide vane is connected with the inner pipe wall of the inner ring and the outer ring of the annular pipe. The axial guide vane is used for guiding all liquid in the flow channel so that the water flow tends to enter the secondary impeller axially.

Preferably, the circumferential array of axial guide vanes is distributed within the annular tube. The circumferential arrays of the axial guide vanes are uniformly distributed in the annular tube, so that the flow state distribution of the inlet of the secondary impeller is more uniform, and vortex which possibly occurs is avoided.

Preferably, the boundary of the annular space is a transition curved surface, and the boundary of the junction of the annular space and the primary impeller is a transition curved surface at the tail end of the flow channel. The junction of the annular space and the axial guide vane is a transition curved surface, so that the water flow is smoother.

The utility model has the beneficial effects that the guide device is reasonably added at the outlet of the back guide vane of the multistage pump, so that the liquid rotation component is eliminated, and meanwhile, the liquid is introduced into the lower impeller; the flow state distribution of the inlet of the secondary impeller is more uniform, vortexes which possibly occur are avoided, the loss in the flowing process is reduced, and the overall hydraulic efficiency of the multistage pump is improved.

Drawings

FIG. 1 is a schematic view of a cross-sectional flow channel of the present utility model;

FIG. 2 is a side view of the present utility model;

FIG. 3 is a schematic diagram of the structure of the present utility model;

1. an axial guide vane; 2. a counter vane; 3. an annular space; 4. a primary impeller; 5. an outlet edge; 6. an inlet edge; 7. and an annular tube.

Detailed Description

The technical solutions of the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present utility model. The described embodiments are only some, but not all, embodiments of the utility model.

As shown in fig. 1, a flow guiding device of a multi-stage pump, wherein a flow channel of the flow guiding device comprises a first-stage impeller 4 at a flow channel initial section, a flow channel tail end of the first-stage impeller is connected with an annular space 3, the tail end of the annular space 3 is connected with a flow channel middle section where a back guide vane 2 is positioned, the tail end of the flow channel middle section is connected with an annular pipe 7 serving as the flow channel tail end, and the axis of the annular pipe 7 is the same as that of a flow guiding structure.

The primary impeller and the annular space are connected with the middle section of the flow passage where the back guide vane 2 is positioned, and the joints of the middle section of the flow passage and the annular pipe 7 at the tail end of the flow passage are connected by adopting transition curved surfaces.

As shown in fig. 1 and 3, the annular tube at the end of the flow passage is provided with axial guide vanes, the axial guide vanes are circumferentially distributed in the annular tube, the bone lines of the axial guide vanes are in a section of circular arc, and the bone lines of the axial guide vanes are on the inner wall of the annular tube in the inner ring of the annular tube.

The vertical distance between the inlet edge 6 of the annular tube and the outlet edge 5 of the annular tube is 38mm, the vertical distance between the nearest end point of the bone line and the inlet edge is 6mm, and the vertical distance between the nearest end point of the bone line and the outlet edge is 5mm.

The 8 axial guide vanes are uniformly distributed along the circumferential direction, the thickness of each axial guide vane is set to be 2.6mm, and the head and the tail are rounded.

The diameter of the circle where the end point of the inlet end of the axial guide vane 1 is located is the same as the diameter of the circle where the end point of the outlet end of the back guide vane is located; the included angle between the tangential direction of the starting point of the bone line of the axial guide vane and the inlet edge 6 is 55 degrees, the included angle between the tangential direction of the end point of the bone line and the outlet edge 5 is 90 degrees, the end point of the bone line is perpendicular to the outlet edge, and the bone line is stretched along the plane perpendicular to the bone line and is connected with the inner wall of the annular tube 7, so that the axial guide vane is obtained. The axial guide vanes cause the water flow to tend to enter the secondary impeller axially, and the circumferential velocity component thereof is reduced.

As shown in FIG. 2, the back guide vane is arranged inside the closed impeller, the middle section of the flow channel is provided with the back guide vane, and the rotating direction of the arc where the back guide vane is positioned is opposite to that of the arc where the impeller guide vane is positioned. The counter-vane changes the radial flow direction of the liquid in the primary impeller, directing the liquid to the axial vane.

The foregoing is only a preferred embodiment of the present utility model, but the scope of the present utility model is not limited thereto, and any person skilled in the art, who is within the scope of the present utility model, should make equivalent substitutions or modifications according to the technical scheme of the present utility model and the inventive concept thereof, and should be covered by the scope of the present utility model.

Claims (8)

1. The flow guiding device of the multistage pump is characterized by comprising a plurality of axial guide vanes (1) of an annular pipe (7) arranged at the tail end of a flow passage and a plurality of back guide vanes (2) connected with an annular space outlet at the middle section of the flow passage;

the flow passage initial section is an annular space (3) connected with the primary impeller (4) and the primary impeller flow passage outlet.

2. The flow guiding device of a multistage pump according to claim 1, wherein the bone line of the axial guide vane is a section of circular arc, and the thickness of the axial guide vane is 2-3 mm.

3. A multistage pump flow guiding device according to claim 2, characterized in that the bone wire ends perpendicular to the outlet edge (5) of the annular tube (7) ends.

4. A flow guiding device for a multistage pump according to claim 2 or 3, characterized in that the angle between the tangent to the origin of the bone line and the inlet edge (6) of the annular tube is 45-65 degrees.

5. The flow guiding device of the multistage pump according to claim 4, wherein the flow passage of the flow passage end section is an annular tube axially parallel to the impeller, and the axial guide vane is arranged on the inner tube wall of the annular tube inner ring.

6. The flow guiding device of a multistage pump according to claim 5, wherein the axial guide vanes are connected with the inner pipe wall of the inner and outer rings of the annular pipe.

7. The flow guiding device of a multistage pump according to claim 6, wherein the circumferential array of axial guide vanes is distributed within the annular tube.

8. The flow guiding device of a multistage pump according to claim 1, wherein the boundary of the annular space is a transition curved surface, the boundary of the junction of the annular space and the flow passage is a transition curved surface.