CN113685358B

CN113685358B - Centrifugal slurry magnetic pump

Info

Publication number: CN113685358B
Application number: CN202111059265.5A
Authority: CN
Inventors: 蒋龙福; 张辉雄; 吴介军
Original assignee: Yixing Zeus Pump Manufacture Co ltd
Current assignee: Yixing Zeus Pump Manufacture Co ltd
Priority date: 2021-09-10
Filing date: 2021-09-10
Publication date: 2024-05-07
Anticipated expiration: 2041-09-10
Also published as: CN113685358A

Abstract

The invention discloses a centrifugal slurry magnetic pump, which comprises a pump shell, an impeller, a main shaft, a shaft sleeve, a middle partition, an inner magnetic steel rotor and an outer magnetic steel assembly, wherein a separation sleeve is arranged between the inner magnetic steel rotor and the outer magnetic steel assembly, one end of the main shaft is connected with the impeller, the other end of the main shaft penetrates through the middle partition to be connected with the inner magnetic steel rotor, the separation sleeve is in sealed connection with one end of the middle partition to form a sealed cavity of the inner magnetic steel rotor, a supporting sleeve is arranged between the shaft sleeve of the main shaft and the middle partition, a first solid-liquid separation cavity is arranged in the pump body, the first solid-liquid separation cavity is an annular cavity formed between the first solid-liquid separation cavity and the middle partition and is positioned behind an impeller web, the impeller web is provided with at least one slurry suction hole and a slag throwing hole, the slurry suction hole is communicated with a pump inlet and the first solid-liquid separation cavity, one end of the slag hole is communicated with the side wall of the first solid-liquid separation cavity, and the other end of the slurry suction hole is communicated with outside the impeller web Zhou Bengqiang. Solid particles can be effectively reduced from entering between the supporting sleeve and the shaft sleeve, the abrasion of the supporting sleeve is reduced, the market demand is met, and the blank of the magnetic pump industry is filled.

Description

Centrifugal slurry magnetic pump

Technical Field

The invention relates to a centrifugal pump, in particular to a magnetic pump capable of conveying slurry containing solid phase.

Background

The magnetic force driven centrifugal pump with the overcurrent component made of plastic has good corrosion resistance and leakage resistance, and is widely applied to various posts for conveying corrosive liquid in the industries of chemical industry, smelting, environmental protection and the like. The magnetic pump is characterized in that the impeller rotates by using the magnetic force of the inner magnetic steel and the outer magnetic steel to transmit torsion as power without rotating shaft dynamic seal, and the inner magnetic steel and the outer magnetic steel are isolated by an isolating sleeve, so that the liquid conveyed in the pump cavity can not leak, and the plastic magnetic force driven centrifugal pump (plastic lining or full plastic) is a conveying pump with good leak resistance and good corrosion resistance.

However, although the magnetic centrifugal pump has good sealing performance, the magnetic centrifugal pump can not convey the slurry of the belt particles for the following reasons:

Firstly, the inner magnetic steel of the plastic magnetic centrifugal pump is required to be wrapped by plastic for corrosion prevention, the isolation sleeve (1) is also made of plastic, the distance between the inner magnet and the isolation sleeve is very small, if the distance between the inner magnet and the isolation sleeve is enlarged, the distance between the inner magnetic steel and the outer magnetic steel is enlarged, the transmission efficiency of magnetic torque force between the inner magnetic steel and the outer magnetic steel is greatly reduced, generally, the distance between the inner wall (1-1) of the isolation sleeve and the periphery of the wrapping body of the inner magnetic steel is only 1-2mm, once the conveyed slurry enters the gap between the inner magnetic steel body and the isolation sleeve, the wrapping layer of the inner magnetic steel is worn out very quickly or the inner magnetic steel is worn out or the isolation sleeve (1) is worn out or the inner rotor is blocked by sand grains, so that the plastic magnetic centrifugal pump always serves as a forbidden zone.

The second is that the rotation supporting part of the plastic magnetic centrifugal pump is a shaft sleeve (2) outside the main shaft and a supporting sleeve (3) sleeved outside the shaft sleeve, and the shaft sleeve (2) and the supporting sleeve (3) are in dynamic sealing. The dynamic combination is not suitable for slurry or particles entering the gap between the shaft sleeve (2) and the supporting sleeve (3), and if the slurry or particles enter the gap, the supporting sleeve can be quickly worn to damage transmission parts, so that the sliding bearing parts of the prior art magnetic pump are not suitable for the working condition of slurry conveying.

The patent (201010195500.7) discloses a magnetic pump for conveying slurry, a sand collecting groove (5-1) and an auxiliary impeller (11-1) are arranged at the position of an inner magnetic steel rotor, fluid in an inner magnetic steel cavity is rotated through the auxiliary impeller, and then centrifugal force is generated by the fluid, sand grains are collected in the sand collecting groove, and then discharged out of the cavity of the inner magnetic steel rotor. However, although the magnetic pump with the structure can reduce some sand grains of fluid at the rotor part of the inner magnetic steel, the sand grains at the sliding bearing part still exist, and the supporting sleeve and the shaft sleeve (or the main shaft) of the magnetic pump can be worn to damage the pump when the pump works, so the magnetic pump also needs to be improved, and the magnetic drive centrifugal pump for conveying slurry is not found in the market at present, so the magnetic pump still needs to be innovated and promoted in the field.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides the centrifugal slurry magnetic pump which can effectively reduce solid particles from entering between the supporting sleeve and the shaft sleeve and reduce the abrasion of the supporting sleeve, meets the market demands and fills the blank of the magnetic pump industry.

In order to achieve the purpose of the invention, the following two technical schemes are provided:

Technical scheme 1: the utility model provides a centrifugal slurry magnetic drive pump, including the pump case, the impeller, the main shaft, the axle sleeve, the middle part, interior magnet steel rotor and outer magnet steel assembly, be provided with the spacer sleeve between interior magnet steel rotor and the outer magnet steel assembly, impeller is connected to main shaft one end, the other end passes middle part connection interior magnet steel rotor, spacer sleeve and middle part one end sealing connection, form interior magnet steel rotor's sealed chamber, be equipped with the supporting sleeve between the axle sleeve of main shaft and the middle part, its characterized in that is provided with first solid-liquid separation chamber in the pump body, first solid-liquid separation chamber is for being located the impeller web rear, form the annular cavity with middle part between, the impeller web is equipped with at least one thick liquid suction port and gets rid of the sediment hole, thick liquid suction port intercommunication pump inlet and first solid-liquid separation chamber gets rid of the sediment hole one end intercommunication first solid-liquid separation chamber lateral wall, the other end intercommunication impeller web is Zhou Bengqiang outward.

Preferably, the back of the impeller web plate is a horizontal plane without radial spokes, at least one circle of convex rings are arranged around the circle center, and a circular array with a plurality of grooves or annular grooves is arranged on the inner side of the convex ring closest to the circle center.

Further preferable as the ballast throwing hole is: the radial through holes are formed in the curved wall of the impeller web plate from the outer side wall to the circle center, and are communicated with the grooves in a one-to-one correspondence manner or communicated with the annular grooves.

As a further improvement, the sealing cavity forms a second solid-liquid separation cavity, a slag discharging hole is formed in the side wall of the annular inner cavity connected with the isolation sleeve on the middle partition part, and the slag discharging hole is communicated with the pump inlet through a pipeline. Further preferably, the annular inner cavity of the middle partition part is provided with an annular slag collecting groove, and the slag discharging hole is arranged at the bottom of the annular slag collecting groove and is arranged along the tangential direction of the annular inner cavity.

Preferably, a rotating wheel is arranged on one side of the inner magnetic steel rotor, and radial protruding strips are arranged on the rotating wheel.

Preferably, the middle partition portion is provided with an annular groove corresponding to the convex ring on the impeller web, and the middle partition portion and the convex ring are mutually coupled.

Preferably, the total cross-sectional area of the slurry suction holes is smaller than the total cross-sectional area of the ballast removal holes.

Preferably, the impeller web diameter is greater than the impeller blade diameter.

Preferably, the middle partition part is provided with a liquid through hole for communicating the first solid-liquid separation cavity and the second solid-liquid separation cavity.

Preferably, the surface of the inner magnetic steel rotor is provided with a plastic coating layer, and a plurality of axial V-shaped sand storage grooves are formed around the surface of the plastic coating layer.

Preferably, the outer surface of the inner magnetic steel rotor matrix is conical, and the isolating sleeve and the inner surface of the outer magnetic steel rotor are correspondingly arranged to be matched conical surfaces.

The second technical scheme is as follows: the utility model provides a centrifugal slurry magnetic drive pump, including pump case, impeller, main shaft, axle sleeve, middle partition portion, interior magnet steel rotor and outer magnet steel assembly, be provided with the spacer sleeve between interior magnet steel rotor and the outer magnet steel assembly, impeller is connected to main shaft one end, the other end passes middle partition portion and connects interior magnet steel rotor, spacer sleeve and middle partition portion one end sealing connection form interior magnet steel rotor's sealed chamber, be equipped with the supporting sleeve between axle sleeve and the middle partition portion of main shaft, its characterized in that interior magnet steel rotor base member is the curved surface that has the sand throwing function, interior magnet steel rotor sets up to assorted curved surface with the mating surface of spacer sleeve, outer magnet steel rotor.

Preferably, the curved surface of the inner magnetic steel rotor matrix is a conical surface, a spherical surface, an arc surface, a plane or an inner concave surface.

Further preferably, the conical surface means that one end of the inner magnetic steel rotor is larger and the other end is smaller, the side close to the motor is smaller, and the side close to the impeller is larger. Most preferably, the taper of the inner magnetic steel rotor is larger than 5 degrees and smaller than 60 degrees based on the central line of the main shaft.

Preferably, the sealing cavity forms a second solid-liquid separation cavity, a slag discharging hole is formed in the side wall of the annular inner cavity connected with the isolation sleeve on the middle partition part, and the slag discharging hole is communicated with the pump inlet through a pipeline.

Preferably, the annular inner cavity of the middle partition part is provided with an annular slag collecting groove, and the slag discharging hole is arranged at the bottom of the annular slag collecting groove and is arranged along the tangential direction of the annular inner cavity.

Preferably, a first solid-liquid separation cavity is arranged in the pump body, the first solid-liquid separation cavity is an annular cavity formed between the impeller web and the middle partition, the impeller web is provided with at least one slurry suction hole and a ballast throwing hole, the slurry suction hole is communicated with the pump suction inlet and the first solid-liquid separation cavity, one end of the ballast throwing hole is communicated with the side wall of the first solid-liquid separation cavity, and the other end of the ballast throwing hole is communicated with the outside Zhou Bengqiang of the impeller web.

20. The centrifugal slurry magnetic pump of claim 19, wherein the back of the impeller web is a horizontal plane without radial spokes, at least one ring of convex rings is arranged around the circle center, and a circular array of a plurality of grooves or annular grooves is arranged on the inner side of the convex ring closest to the circle center.

Preferably, the ballast throwing holes are a plurality of radial through holes formed in the thickness of the curved surface of the impeller web plate from the outer side wall to the circle center, and the radial through holes are communicated with the grooves in a one-to-one correspondence manner or communicated with the annular grooves.

Preferably, the surface of the magnetic steel rotor is provided with a plastic coating layer, and a plurality of axial V-shaped sand storage grooves are formed around the surface of the plastic coating layer.

The invention has the beneficial effects that:

Through the improvement of the impeller and the pump cavity internal structure, the solid-phase materials in the liquid of the magnetic steel rotor part in the magnetic pump bearing part can be reduced, the pump can run more safely, the magnetic pump which can not convey slurry originally can convey slurry, and the blank in the industry is filled. The leakage resistance of the magnetic pump is thoroughly improved, the leakage-free shaft-sealed centrifugal slurry pump is obtained, and the quality level of domestic similar products is improved.

Drawings

Fig. 1 is a schematic structural diagram of embodiment 1.

Fig. 2 is a schematic view of the impeller of fig. 1.

FIG. 3 is a schematic view of the septum of FIG. 1.

Fig. 4 is a front view of the inner magnetic steel rotor of embodiment 2.

Fig. 5 is a left side view of fig. 4.

Fig. 6 is a schematic structural diagram of embodiment 4.

Fig. 7 is a partial schematic view of b-b of fig. 6.

Fig. 8 is a schematic view of the inner magnet steel rotor of fig. 6.

Fig. 9 is a schematic view of the outer magnet steel rotor of fig. 6.

Fig. 10 is a schematic structural view of embodiment 5.

Fig. 11 is a schematic structural diagram of embodiment 6.

FIG. 12 is a schematic diagram of the mechanism of example 7.

FIG. 13 is a schematic view of the integration of the septum and the pump body.

Fig. 14 is a schematic view of the pump cover being provided at the suction port portion of the impeller.

FIG. 15 is a schematic view of the independent fabrication of the housing of the second solid-liquid separation chamber.

Fig. 16 is a schematic view of an impeller with a semi-open impeller.

Detailed Description

Example 1: as shown in fig. 1 and 2, a centrifugal slurry magnetic pump comprises a pump body 7, an impeller 6, a main shaft 9, a shaft sleeve 2, a middle partition 5, a front thrust ring 4, a rear thrust ring 10, a mounting seat 13, a motor 12, an inner magnetic steel rotor 11 and an outer magnetic steel assembly 14, wherein a separation sleeve 1 is arranged between the inner magnetic steel rotor 11 and the outer magnetic steel assembly 14, one end of the main shaft 9 is connected with the impeller 6, the other end passes through the middle partition 5 and is connected with the inner magnetic steel rotor 11, the separation sleeve 1 is in sealing connection with one end of the middle partition 5 to form a sealing cavity of the inner magnetic steel rotor 11, a supporting sleeve 3 is arranged between the shaft sleeve 2 of the main shaft 9 and the middle partition 5, a first solid-liquid separation cavity a is arranged in the pump body 7 and is positioned behind an impeller web 6-1, an annular cavity is formed between the middle partition 5, the back of the impeller web 6.1 is a horizontal plane without radial radiation, a circle of convex rings 6-3 is arranged around the circle center, the middle partition 5 is provided with annular grooves corresponding to the convex rings 6-3 on the impeller web 6-1, and the two cavities are mutually coupled to form a sealed cavity which is opposite to the first solid-liquid separation cavity and the outside cavity; the inner side of the convex ring 6.3 is provided with a circular array with a plurality of grooves 6-5. The slurry suction hole 6-4 formed in the impeller web 6-1 is communicated with the pump suction inlet 15 and the first solid-liquid separation cavity a, one end of the ballast throwing hole 6-2 is communicated with the side wall of the first solid-liquid separation cavity a, the other end of the ballast throwing hole is communicated with the peripheral pump cavity of the impeller web 6-1, the ballast throwing hole 6-2 is a radial through hole formed in the curved wall of the impeller web 6-1 from the outer side wall to the circle center, and the radial through hole is correspondingly communicated with the grooves 6-5. The sealing cavity forms a second solid-liquid separation cavity b, a slag discharging hole 5-3 is arranged on the side wall of the annular inner cavity connected with the isolation sleeve 1 on the middle partition part 5, and the slag discharging hole 5-3 is communicated with the pump suction inlet 15 through a pipeline. The annular inner cavity of the middle partition part 5 is provided with an annular slag collecting groove 5-1, and the slag discharging hole 5-3 is arranged at the bottom of the annular slag collecting groove 5-1 and is arranged along the tangential direction of the annular inner cavity. The purpose of the arrangement is that sand grains rotating on the inner wall of the volute can flow into the ballast discharging holes 5-3 in the same direction and be discharged out of the cavity. One side of the inner magnetic steel rotor 11 is provided with a rotating wheel 11-1, the rotating wheel 11-1 is provided with radial convex strips, the total sectional area of the slurry suction hole is smaller than that of the ballast throwing hole, and the diameter of the impeller web 6-1 is larger than that of the impeller blades. The main shaft 9 is made of integral silicon carbide material.

The bearing sleeve is made of materials such as tetrafluoroethylene filled carbon graphite and the like for the sliding bearing sleeve 3. The front thrust ring 4 and the rear thrust ring 10 are made of silicon carbide or toughened ceramic materials. The inner magnetic steel rotor 11 is made of neodymium iron boron magnetic steel and is coated with a perfluorinated ethylene propylene material. The isolation sleeve 1 can be made of carbon fiber composite resin and then is internally lined with a structure of poly-perfluoroethylene propylene. The second solid-liquid separation cavity b is made of steel lining ultra-high molecular weight polyethylene material. The rotating wheel 11-1 is made of ultra-high molecular weight polyethylene material.

After the components are manufactured according to the figures and the material requirements, the components can be assembled: the magnetic pump is characterized in that the sliding bearing 3 is sleeved in the middle hole of the middle partition part 5, the inner magnetic steel rotor body 11 and the rear thrust ring 10 are respectively sleeved on the silicon carbide main shaft 9, the main shaft 9 passes through the middle hole of the sliding bearing, then the parts such as the second solid-liquid separation cavity shell 5 of the impeller 6 of the front thrust ring 4, the installation seat 13 of the pump shell 7 of the isolation sleeve 1 and the like are sequentially assembled, and when the magnetic pump is installed, a leakage-proof bed is required to be padded on each part, and after the parts are fastened by fastening bolts, the magnetic pump can be obtained.

Example 2: as shown in fig. 3, in example 1, the remaining features are not changed, and only the middle partition portion is provided with a liquid passage hole 5-2 for communicating the first solid-liquid separation chamber a and the second solid-liquid separation chamber b. Filling the second solid-liquid separation cavity with fluid.

Example 3: as shown in fig. 4 and 5, referring to embodiment 1, the remaining features are unchanged, the surface of the inner magnetic steel rotor is provided with a plastic coating layer, and a plurality of axial V-shaped sand storage grooves 11-2 are formed around the surface of the plastic coating layer. The plastic coating layer of the inner magnetic steel rotor is prevented from being scratched by sand grains.

Example 4: as shown in fig. 6, 7, 8 and 9, referring to embodiment 1, the other characteristics are unchanged, a rotating wheel 11-1 is arranged on one side of an inner magnetic steel rotor 11, radial convex strips are arranged on the rotating wheel 11-1, liquid passing holes 11-3 are arranged on a substrate of the inner magnetic steel rotor 11, a blade 11-4 is arranged at the rotating wheel, the substrate of the inner magnetic steel rotor is a conical surface with a sand throwing function, and the matching surfaces of the inner magnetic steel rotor 11, the isolation sleeve 1 and the outer magnetic steel rotor 14 are conical surfaces which are matched. The conical surface is that one end of the inner magnetic steel rotor 11 is big and the other end is small, the side close to the motor is small, and the side close to the impeller is big. The taper of the inner magnetic steel rotor 11 takes the central line of the main shaft as a reference, and the taper is 10 degrees.

The inner magnetic steel rotor is formed by wrapping neodymium iron boron magnetic steel into a whole by fluoroplastic, the angle of the contact surface of the metal core contacted by the inner magnetic steel is processed into 10 DEG taper, and the mould for mould pressing the lining rotor is also formed by mould pressing according to the 10 DEG taper, and is processed.

The outer magnetic steel rotor also adopts neodymium iron boron magnetic steel, and is processed and manufactured according to the requirements of conical magnetic steel.

The inner peripheral surface of the outer magnetic steel rotor assembly is also processed into a 10-degree cone shape of the isolating sleeve, which is matched with the outer peripheral surface of the isolating sleeve.

Example 5: as shown in fig. 10, referring to embodiment 4, the curved surface of the magnetic steel rotor base body is a spherical curved surface without changing the other characteristics.

Example 6: as shown in fig. 11, referring to example 4, the remaining features are unchanged, and the curved surface of the inner magnetic steel rotor base body is a plane.

Example 7: as shown in fig. 12, referring to example 4, the remaining features are unchanged, and the curved surface of the inner magnetic steel rotor base is an inner concave surface.

In the above embodiments 1 to 7, the pump body 7 and the impeller 6 are made of steel lining ultra-high molecular weight polyethylene material.

The middle partition 5 in the above examples 1 to 7 was made of a material of steel body 5-5 coated with poly-perfluoroethylene propylene (F46). The middle partition part 5 is a partition part between the pump body and the isolation cover and comprises a cavity connected with the pump body, a shaft cavity used for placing the supporting shaft and a cavity connected with the isolation cover and used for sealing the inner magnetic steel rotor.

The working principle of the invention is as follows: after the pump is started, the slurry in the slurry suction hole 6-4 on the impeller enters the first solid-liquid separation cavity a, under the rotation of the impeller, centrifugal force is generated in the first solid-liquid separation cavity a, the centrifugal force concentrates the solids to the periphery of the first solid-liquid separation cavity a, under the suction action of the ballast throwing hole 6-2, the separated clear liquid medium is discharged into the pump cavity, the clear liquid medium is remained at the center of the first solid-liquid separation cavity, enters the sliding bearing 3 and then enters the second solid-liquid separation cavity b, when the clear liquid in the first solid-liquid separation cavity enters the second solid-liquid separation cavity b, the rotation of the rotating wheel 11-1 and the inner magnetic rotor drives the fluid to rotate, and under the action of the centrifugal force, a small amount of solids of the liquid are separated into the annular ballast collecting groove 5-1 of the second solid-liquid separation cavity, enter the ballast discharging hole 5-3 and are discharged out of the pump cavity. The solid content in the liquid in the inner magnetic steel rotor cavity 11 is greatly reduced, so that the inner magnetic steel rotor works in a relatively clean liquid environment, and the operation safety of the inner magnetic steel rotor is ensured.

The middle partition 5 in embodiments 1-7 may be integrally formed with the pump body 7 (fig. 13), and the pump cover is provided at the suction port of the impeller (fig. 14), and this design has the advantage of convenient assembly and disassembly, since the pump cover of the slurry centrifugal pump is easily worn and damaged, and the maintenance amount is large, so that the running cost can be saved by such a structure.

The second solid-liquid separation chamber in examples 1 to 4 may be formed as a separate body (fig. 15), may be formed integrally with the septum (fig. 3), or may be formed integrally with the pump body (fig. 13).

In example 1, the slag discharging hole 5-3 can be communicated with the suction inlet pipeline of the pump to allow sand grains to enter the pump suction inlet, and can also be directly discharged into the waste slurry collecting tank, and when the pressure of the fluid at the pump suction inlet is higher than that of the second solid-liquid separation cavity, the slurry at the slag discharging hole 5-3 must be discharged into the waste liquid collecting system.

In the above embodiments 1 to 7, the impeller 6 may be a semi-open impeller (fig. 16) or a closed impeller (fig. 2), and is not limited in this embodiment.

The impeller web is provided with a ballast throwing hole 6-2, the aperture of which is determined according to the solid content of the conveyed materials, and the diameter of the particles can be selected within a range of 6-20 mm.

The number of the holes of the impeller web provided with the ballast throwing holes 6-2 is determined according to the ballast discharging effect and the size of the pump, and is generally between 6 and 18, and the invention is not limited.

The length of the slag throwing hole formed in the impeller is determined according to the outer diameter of the impeller web, and the diameter of the web of the slag throwing hole is generally larger than the outer diameter of the impeller main blade.

The impeller may be made of non-metal materials such as plastics and ceramics, or metal materials with corrosion resistance and wear resistance, and is not limited in the invention.

The magnetic steel of the inner magnetic steel rotor 11 and the outer magnetic steel rotor can be rare earth magnetic steel such as neodymium iron boron, cobalt, etc.

The sliding bearing described in example 1 is an embodiment of the invention, and ceramic rolling bearings or other transmission methods may be used instead of the sliding bearing described in the example.

Examples 1-7 are preferred embodiments of the present invention, and one skilled in the art can achieve the object of the present invention by adding or subtracting solid-liquid separation modules and changing the solid-liquid separation structure, but any structural changes and functional substitutions are within the scope of the present invention.

Claims

1. The centrifugal slurry magnetic pump comprises a pump shell, an impeller, a main shaft, a shaft sleeve, a middle partition, an inner magnetic steel rotor and an outer magnetic steel assembly, wherein a spacer sleeve is arranged between the inner magnetic steel rotor and the outer magnetic steel assembly, one end of the main shaft is connected with the impeller, the other end of the main shaft penetrates through the middle partition to be connected with the inner magnetic steel rotor, the spacer sleeve is in sealing connection with one end of the middle partition to form a sealing cavity of the inner magnetic steel rotor, and a supporting sleeve is arranged between the shaft sleeve of the main shaft and the middle partition.

2. The centrifugal slurry magnetic pump of claim 1, wherein the sealing chamber forms a second solid-liquid separation chamber, a slag discharging hole is formed in the side wall of the annular inner chamber connected with the isolation sleeve on the middle partition part, and the slag discharging hole is communicated with the pump inlet through a pipeline.

3. The centrifugal slurry magnetic pump of claim 1, wherein the annular cavity of the middle partition is provided with an annular slag collecting groove, and the slag discharging hole is formed at the bottom of the annular slag collecting groove and is formed along the tangential direction of the annular cavity.

4. The centrifugal slurry magnetic pump as claimed in claim 1, wherein a first solid-liquid separation chamber is provided in the pump body, the first solid-liquid separation chamber is an annular cavity formed between the impeller web and the middle partition, the impeller web is provided with at least one slurry suction hole and a ballast throwing hole, the slurry suction hole is communicated with the pump suction inlet and the first solid-liquid separation chamber, one end of the ballast throwing hole is communicated with the side wall of the first solid-liquid separation chamber, and the other end is communicated with the outside Zhou Bengqiang of the impeller web.

5. The centrifugal slurry magnetic pump of claim 4, wherein the back of the impeller web is a horizontal plane without radial spokes, at least one ring of convex rings is arranged around the circle center, and a circular array of a plurality of grooves is arranged on the inner side of the convex ring closest to the circle center.

6. The centrifugal slurry magnetic pump of claim 4, wherein the ballast throwing holes are a plurality of radial through holes formed in the curved wall of the impeller web from the outer side wall to the center of a circle, and the radial through holes are communicated with the grooves in a one-to-one correspondence.

7. The centrifugal slurry magnetic pump of claim 1, wherein a rotor is provided on one side of the inner magnetic steel rotor, and radial ribs are provided on the rotor.

8. The centrifugal slurry magnetic pump of claim 1, wherein the middle partition is provided with a liquid through hole for communicating the first solid-liquid separation cavity and the second solid-liquid separation cavity.

9. The centrifugal slurry magnetic pump of claim 1, wherein the inner magnetic steel rotor surface is provided with a plastic coating layer, and a plurality of axial V-shaped sand storage grooves are formed around the plastic coating layer surface.