CN218151648U - Improved centrifugal pump without water cooling - Google Patents

Abstract

The utility model discloses an improved generation need not water-cooled centrifugal pump, relate to the slurry pump field that contains the solid volume greatly, including the pump case, the pump cover, main shaft in the pump case, impeller and axle seal assembly, the impeller includes the impeller web, the positive impeller blade of impeller web, the impeller web back and pump case inner wall, the preceding terminal surface of axle seal, main shaft axle sleeve outer peripheral face encloses into the liquid storage chamber, at least one logical liquid hole has been seted up to the axial on the impeller web plate body, the logical liquid hole link up the liquid storage chamber and pump case inner chamber, the impeller web back is provided with radial sand grip around the centre of a circle, passageway between adjacent sand grip constitutes open decompression runner, decompression runner link up liquid storage chamber and pump case inner chamber, the axle sleeve section periphery that is located the liquid storage chamber is equipped with the liquid separation barrel casing, liquid separation barrel casing and pump body rigid coupling. Effectively prevent the blockage of the pressure reduction flow channel, keep the fluid negative pressure state at the shaft sealing position, and can convey slurry with the solid content of more than 30 percent in volume ratio for a long time without water cooling.

Description

Improved centrifugal pump without water cooling

Technical Field

The utility model relates to a centrifugation slurry pump field especially relates to carry the higher centrifugation slurry pump of solid content.

Background

The common shaft seal of the centrifugal pump for conveying slurry adopts mechanical seal, lip-shaped seal ring seal and the like. However, these shaft seals all have a common deficiency: all must external cooling water carry out the water-cooling and wash, not only need consume the water resource, but also can produce secondary pollution to the environment, increase user's environmental protection cost.

In order to overcome the defects, the patent number CN111120397A of the company discloses a centrifugal slurry pump 8194and discloses a sealing structure without cooling water, the technical scheme of the centrifugal slurry pump 8194is that a plurality of pressure reduction flow passages 2.1 (shown in figure 1) are radially arranged from the outer side wall to the inner side in the wall thickness of a curved surface of an impeller 2 amplitude plate, the back surface of the impeller amplitude plate is convexly and concavely matched with the inner surface of a pump shell, the back surface of the impeller amplitude plate, the inner wall of the pump shell, the front end surface of a shaft seal and the outer peripheral surface of a main shaft are encircled to form a liquid storage cavity 1, and the pressure reduction flow passages 2.1 penetrate through the liquid storage cavity 1 and the inner cavity of the pump shell. By adopting the liquid storage cavity 1, the pressure reduction flow channel 2.1 on the impeller and the liquid through hole 3, when the pump machine operates, the liquid storage cavity 1 close to the machine seal is pumped into a negative pressure state through the centrifugal action of the pressure reduction flow channel 2.1, so that the machine seal operates in the negative pressure state, the pressure ratio between a moving ring and a static ring of the machine seal is reduced, and the heating value of the friction kettle of the machine seal is reduced. The utility model discloses of above-mentioned technique for the slurry centrifugal pump also can carry the slurry that contains solid content height under the prerequisite of not external cooling water, nevertheless practice proves, and above-mentioned utility model technique's product still exists following not enoughly: namely, the pressure reducing flow passage on the impeller amplitude plate is in a closed state: the pressure reducing flow passage in a closed state is difficult to pass through slurry with high solid content, and when the mineral solid content of the slurry conveyed exceeds 20% of the volume ratio, the pressure reducing flow passage 2.1 on the impeller is blocked by thick slurry, so that the vacuum degree of the liquid storage containing cavity 1 is insufficient, further, the components of the combined machine seal are damaged, and the machine seal is damaged.

If the structure of the pressure reducing flow channel is changed, the closed pressure reducing flow channel is changed into an open structure 2.2 (as shown in figure 2), so that the sealing performance of the liquid storage cavity 1 between the impeller amplitude plate and the pump shell 4 is poor, partial vacuum of a sealing part can not be formed, the mechanical seal of the centrifugal pump can only work in a positive pressure fluid state, the mechanical seal can still generate heat, the seal still needs cooling water, and the purpose that the mechanical seal of the pump can not be added with cooling water can still be achieved.

SUMMERY OF THE UTILITY MODEL

The utility model discloses to prior art's is not enough, provides one kind and effectively prevents that the decompression runner from blockking up to keep shaft seal department fluid negative pressure state, can need not the water-cooling and carry the improved generation that solid content surpassed 30% volume ratio ground paste for a long time and need not water-cooled centrifugal pump.

For realizing the purpose of the utility model, the following technical proposal is provided: a centrifugal pump without water cooling comprises a pump shell, a pump cover, a main shaft, an impeller and a shaft sealing assembly, wherein the main shaft, the impeller and the shaft sealing assembly are arranged in the pump shell, the impeller comprises an impeller amplitude plate and impeller blades on the front side of the impeller amplitude plate, the back of the impeller amplitude plate, the inner wall of the pump shell, the front end face of the shaft seal and the outer peripheral face of a shaft sleeve of the main shaft surround a liquid storage cavity, at least one liquid through hole is axially formed in a plate body of the impeller amplitude plate and penetrates through the liquid storage cavity and an inner cavity of the pump shell, the centrifugal pump is characterized in that radial raised strips are arranged on the back of the impeller amplitude plate around the circle center, channels between the adjacent raised strips form an open pressure reduction flow channel, the pressure reduction flow channel penetrates through the liquid storage cavity and the inner cavity of the pump shell, a liquid separation barrel sleeve is arranged on the periphery, close to a shaft sleeve section in the liquid storage cavity, and the liquid separation barrel sleeve is fixedly connected with the pump body. The liquid-isolating sleeve can prevent the pressure fluid from flowing back to the sleeve, so that the relief pattern on the sleeve can effectively reduce pressure during rotation and the pressure of the fluid in the shaft sealing part can still be maintained in negative pressure state when the pressure reducing flow passage is in developed structure.

The arrangement of the radial raised lines enables the channels between the adjacent raised lines to form an open pressure reduction flow channel, which can effectively prevent the pump from blocking when conveying thick slurry and overcome the defect that the suction hole of the impeller in the prior art is easily blocked by the thick slurry.

Preferably, the outer periphery of the sleeve section of the main shaft sleeve positioned in the liquid storage cavity is provided with a convex line I inclined towards one side of the impeller. The raised lines which are inclined towards one side of the impeller are arranged on the periphery of the shaft sleeve section of the shaft sleeve of the main shaft, which is positioned in the liquid storage cavity, so that when the main shaft rotates, the fluid at the shaft sealing part is pushed towards the pump cavity part (the impeller direction) through the rotation of the main shaft and the raised lines which are inclined towards one side of the impeller, the effect of reducing the fluid pressure at the shaft sealing part is achieved, and the fluid pressure at the sealing part is in a negative pressure state. Further preferably, the ribs inclined to the impeller side are trapezoidal threads or double-start threads. In order to increase the thrust of the ribs on the fluid during operation and to increase the vacuum in the mechanical seal, it is preferred to increase the length of the thread segments so that the length of the thread segments is between 3 and 8cm, preferably 4 to 6cm.

Preferably, the inner wall of the liquid-proof cylinder sleeve is provided with a second embossment which inclines towards the impeller side.

Preferably, the liquid isolating cylinder sleeve wall is provided with a backflow hole, one end of the backflow hole penetrates through the front end face of the near-shaft seal, and the other end of the backflow hole penetrates through the liquid storage cavity. The backflow hole is arranged to match with the shaft seal at the rear side, and when the shaft seal is a lip seal ring, the lip seal ring is washed through the backflow hole.

Preferably, the shaft seal assembly comprises a shaft seal, the shaft seal being a lip seal or a mechanical seal or a combination of both.

Preferably, the rear side of the shaft sealing assembly is provided with a wind wheel.

The centrifugal pumps are front suction centrifugal pumps, side suction centrifugal pumps, horizontal centrifugal pumps and vertical centrifugal pumps.

The impeller of the centrifugal pump is a semi-open impeller or a closed impeller or a semi-open impeller with a mouth ring.

The utility model discloses beneficial effect: through the utility model discloses the centrifugal pump of technique preparation has overcome the centrifugal slurry pump that does not seal cooling water among the original technique, when carrying the ground paste more than 20% solid content, can block up the negative pressure suction hole, and then makes the sealed damage of pump shaft. Through the utility model discloses an after the improvement, under the prerequisite of not external cooling water, pump machine vacuum suction system can not block up, can carry the ground paste that contains solid more than 20%.

Drawings

Fig. 1 is a schematic diagram of the prior art.

Fig. 2 is a sectional view of an impeller of an open type pressure reducing flow passage of the related art.

Fig. 3 is a front view of the impeller of fig. 1 provided with a closed pressure reduction flow passage.

Fig. 4 is a half sectional view of fig. 3.

FIG. 5 is a front view of embodiment 1.

Fig. 6 is a schematic view of the shaft sleeve section of the first shaft sleeve in fig. 5, which is provided with trapezoidal threads inclined towards the impeller side at the periphery.

Fig. 7 is a front view of the impeller of fig. 5.

Fig. 8 is a half sectional view of fig. 7.

Fig. 9 is a schematic view of a double-start thread structure of a rib inclined to one side of the impeller on the first shaft sleeve.

Fig. 10 is a schematic view of a boss having an irregular concave-convex inclined groove as a convex pattern inclined to one side of the impeller.

FIG. 11 is a schematic view of example 2.

FIG. 12 is a schematic view of example 3.

FIG. 13 is a schematic view of example 4.

FIG. 14 is a schematic view of example 5.

Figure 15 is a schematic view of the fluid barrier sleeve of figure 14.

FIG. 16 is a schematic view of example 6.

Detailed Description

Embodiment 1, as shown in fig. 5, 6, 7, and 8, a horizontal centrifugal pump without water cooling includes a pump housing 1, a pump cover 3, a main shaft 4, an impeller 2, a shaft seal assembly, a bearing bracket 14, a bearing 15, a bearing cover 16, a coupling 17, a motor 18, and fastening bolts 20 of each part of a mounting base 19 in the pump housing 1, the impeller 2 is an open impeller, and includes an impeller vane 2.2 on the front of the impeller 2.2, the back of the impeller 2.2, the inner wall of the pump housing 1, the front end of a lip seal 9, and the outer peripheral surface of a main shaft sleeve 5 enclose a liquid storage chamber 21, 3 liquid through holes 2.3 are axially formed on the body of the impeller 2.2, the liquid through holes 2.3 penetrate through the liquid storage chamber 21 and the inner chamber of the pump housing 1, the shaft seal assembly includes a shaft seal, a seal box 11, and a seal box cover 12, the shaft seal is composed of a front seal and a rear seal, the front seal is two groups of lip-shaped seal rings 9, the rear seal is a mechanical seal 10 with moving and static rings 10.2 and 10.1, a wind wheel 13 is arranged on the rear side of the mechanical seal 10, radial convex strips 2.4 are arranged on the back surface of an impeller web 2.2 around the circle center, channels between the adjacent convex strips 2.4 form an open pressure reduction flow channel 2.5, the pressure reduction flow channel 2.5 penetrates through a liquid storage cavity 21 and an inner cavity of a pump shell 1, trapezoidal threads 5.1 inclined towards one side of an impeller are arranged on the periphery of a shaft sleeve section of a first main shaft sleeve 5 positioned in the liquid storage cavity 21, a liquid separation sleeve 7 is arranged on the periphery of a shaft sleeve section sleeved in the liquid storage cavity 21, the liquid separation sleeve 7 is fixedly connected with a pump body 1, a backflow hole 7.1 is arranged on the liquid separation sleeve 7, one end of the backflow hole 7.1 penetrates through the front end face of the lip-shaped seal ring 9, and the other end penetrates through the liquid storage cavity 21.

Set up lip rubber seal's aim at: firstly, the mechanical seal 10 is used for blocking sand, when a pump machine conveys slurry of solid-phase materials, particles in the slurry can enter the movable ring part and the static ring part of the mechanical seal 10, and further the movable ring and the static ring of the mechanical seal are worn, and after the lip-shaped seal ring 9 is arranged, the slurry in a pump cavity can be prevented from entering the inner cavity of the mechanical seal part; secondly, the lip elastic force of the lip-shaped sealing ring 9 is utilized to prevent the impact of the pump machine on the water hammer of the mechanical seal when the pump machine is stopped, thereby playing the role of protecting the mechanical seal.

The parts are manufactured according to the manufacturing mode of a conventional corrosion-resistant wear-resistant centrifugal pump:

the pump shell 1, the pump cover 3 and the impeller 2 are made of steel-plastic composite structures. The plastic of the steel-plastic composite structure is made of ultra-high molecular weight polyethylene and is manufactured by a hot press molding method. When the pump shell is manufactured, an annular concave pit is manufactured at the joint of the pump shell 1 and the impeller 2, and the purpose of manufacturing the concave pit is to enable the concave pit 1.1 on the pump shell and the concave pit 2.1 on the impeller to surround a liquid storage cavity 21. The main shaft 4, the shaft seat 14, the mounting bottom plate 19, the wind wheel 13 and other components are manufactured by casting, machining and other procedures according to a conventional method. The first shaft sleeve 5 is made of ceramic, and the second shaft sleeve 6 is made of stainless steel. When the first shaft sleeve 5 is manufactured, trapezoidal threads are machined on the outer peripheral surface of the shaft sleeve. The inclination rate of the trapezoidal threads can be determined according to parameters of the diameter of the shaft sleeve and the rotating speed of the main shaft, and the purpose is to push the fluid to move forwards. The liquid separation cylinder sleeve 7 is made of ultra-high molecular weight polyethylene by a hot press molding process, and a backflow hole 7.1 is formed in the liquid separation cylinder sleeve 7. The mechanical seal 10, the lip-shaped seal ring 9, the bearing 15, the wind wheel 13 and the fastening screw 20 can be purchased from the market or obtained by external cooperation. After all parts are manufactured, the components can be assembled and installed according to the installation process of the conventional and anticorrosive centrifugal pumps: the main shaft 4, the bearing 15, the bearing support 14 and the bearing gland 16 are assembled together. And a wind wheel 13, a first shaft sleeve 5, a movable ring 10.2 and a second shaft sleeve 6 are arranged on the main shaft. The pump shell 1 is provided with a liquid-proof cylinder sleeve 7, a sealing box 11, a machine seal static ring 10.1 and a static ring gland 12. Then the pump shell 1 and the shaft seat 14 are assembled together in sequence, and the impeller 2 and the fastening piece 22 for fastening the impeller are arranged on the main shaft 4. And then the pump cover 3, the shaft coupling 17, the motor 18 and the base 19 are assembled together in sequence, thus obtaining the complete centrifugal pump capable of conveying slurry.

In the embodiment 1, in order to prevent the particles in the slurry from entering the inner cavity of the mechanical seal through the backflow hole of the liquid isolating cylinder sleeve to abrade the mechanical seal, the pump shell 1 is provided with the annular concave part 1.1, and the impeller web is provided with the liquid through hole 2.3. An annular concave part is arranged at the rear side of the impeller amplitude plate close to the center part. When the pump is installed, the annular concave part 2.1 on the impeller and the annular concave part 1.1 on the pump shell enclose an annular liquid storage cavity 21, when the pump is started, slurry in the annular cavity 21 is driven by the impeller to rotate rapidly, the rotating fluid separates solid matters of the slurry in the cavity to the edge part of the cavity under the action of gravity and centrifugal force, and then the solid matters are discharged into the volute of the pump cavity from the clearance of the convex strip of the back blade, so that the fluid near the periphery of the liquid separation barrel sleeve 7 in the liquid storage cavity 21 is in a clear liquid state, and then the fluid enters the position of the lip-shaped sealing ring 9 from the return hole 7.1 on the liquid separation barrel sleeve 7, and the flushing fluid at the sealing position is also in a clear liquid state. The structure can prevent the liquid through hole from being blocked, reduce the solid of the lip-shaped ring part, reduce the abrasion of the lip-shaped ring and prolong the service life.

Example 2: referring to embodiment 1, the impeller 2, main shaft 4 and shaft seal assembly structure can be used in a vertical centrifugal pump (see fig. 11).

Example 3: referring to embodiment 1, the impeller 2, main shaft 4 and shaft seal assembly structure can be used for a direct centrifugal pump without a bearing seat (see fig. 12).

Example 4: referring to example 1, the impeller 2, main shaft 4 and shaft seal assembly arrangement can be used in a side draft centrifugal pump (see fig. 13).

Example 5: referring to embodiment 1, as shown in fig. 14 and 15, the remaining features are unchanged, and the inner wall of the liquid barrier sleeve 7 is provided with a trapezoidal thread inclined toward the impeller 2 side.

Example 6: referring to embodiment 1, as shown in fig. 16, a horizontal centrifugal pump without water cooling includes a pump housing 1, a pump cover 3, a main shaft 4, an impeller 2, a shaft seal assembly, a bearing bracket 14, a bearing 15, a bearing gland 16, a coupler 17, a motor 18, and fastening bolts 20 for each part of a mounting base 19 in the pump housing 1, wherein the impeller 2 is an open impeller, and includes an impeller web 2.2 and impeller blades 2.6 on the front side of the impeller web 2.2, the back side of the impeller web 2.2 surrounds a liquid storage cavity 21 with the inner wall of the pump housing 1, the front end face of a lip-shaped seal ring 9, and the outer peripheral surface of a main shaft sleeve 5, 3 liquid through holes 2.3 are axially formed in the plate body of the impeller web 2.2, the liquid through holes 2.3 penetrate through the liquid storage cavity 21 and the inner cavity of the pump housing 1, the shaft seal assembly includes a shaft seal, a seal box 11, and a seal box cover 12, the shaft seal is composed of a front seal and a rear seal, the front seal is two groups of lip-shaped seal rings 9, the rear seal is a mechanical seal 10 containing a moving ring 10.2 and a static ring 10.1, a wind wheel 13 is arranged on the rear side of the mechanical seal 10, radial convex strips 2.4 are arranged on the back surface of an impeller web 2.2 around the circle center, channels between the adjacent convex strips 2.4 form an open pressure reduction flow channel 2.5, the pressure reduction flow channel 2.5 penetrates through a liquid storage containing cavity 21 and an inner cavity of a pump shell 1, a liquid separation cylinder sleeve 7 is arranged on the periphery of a shaft sleeve section sleeved in the liquid storage containing cavity 21, the liquid separation cylinder sleeve 7 is fixedly connected with the pump body 1, a backflow hole 7.1 is formed in the cylinder wall of the liquid separation cylinder sleeve 7, one end of the backflow hole 7.1 penetrates through the front end face of the lip-shaped seal ring 9, the other end penetrates through the liquid storage containing cavity 21, and trapezoidal threads inclined towards one side of the impeller 2 are arranged on the inner wall of the liquid separation cylinder sleeve 7.

The material of the flow passage component in the above embodiment can be made of metal material and non-metal material.

In the above embodiment, the material of the first bushing 5 may be ceramic or metal.

The convex ridge inclined towards the impeller side on the first shaft sleeve 5 in the above embodiment can also be a thread (as shown in fig. 9) or an irregular concave-convex inclined groove (as shown in fig. 10).

The utility model discloses the structure has constituted following new function and advantage when the pump machine operation: firstly, after the threaded section 5.1 and the liquid-isolating cylinder sleeve 7 are arranged on the shaft sleeve, a new pressure reduction function is immediately generated at the 5 part of the shaft sleeve, the raised line 2.4 of the impeller is used for reducing the pressure of the sealing part for the first time when the pump operates, the pressure of fluid is reduced for the liquid outlet of the threaded section 5.1 in advance, then the secondary pressure reduction is carried out at the combined part of the threaded section 5.1 and the liquid-isolating cylinder sleeve 7, and after the pressure reduction is carried out for the first time and the second time, the fluid in the inner cavity of the mechanical seal operation is in a negative pressure state, the internal environment condition of the mechanical seal operation is improved, the mechanical seal is not washed by pressure slurry, and the service life of the mechanical seal is longer; secondly, after the liquid isolating cylinder sleeve 7 is arranged, the inner cavity 21 of the mechanical seal part is relatively isolated from the pump cavity, so that the fluid pressure in the inner cavity of the seal part is not fluctuated by the fluid pressure in the pump cavity, the mechanical seal works in an environment with balanced fluid pressure, the stability of the mechanical seal during working is improved, and the defects that the mechanical seal 10 and the lip-shaped seal ring 9 are damaged due to the fact that the fluid pressure of the mechanical seal part is unstable because the open convex strip is used for reducing the pressure of the mechanical seal at the back of an impeller amplitude plate in the prior art and the fluid pressure of the mechanical seal part is changed by the fluid pressure in the pump cavity are overcome; thirdly, owing to remain the step-down structure of open sand grip behind the impeller web, do not adopt the step-down structure that sets up decompression runner 2.5 on the web for can not be like original technique when the pump machine carries thick liquid, confined decompression runner 2.5 is blockked up, makes the utility model discloses a technique has following advantage simultaneously: namely, the thick slurry can not be blocked by the hole, the thick slurry with the solid content of about 30 percent can be conveyed, and the liquid contacted with the component of the sealing part is the clear liquid in a relatively negative pressure state, so the mechanical seal is not easy to damage.

Claims (9)

1. The improved centrifugal pump without water cooling comprises a pump shell, a pump cover, a main shaft in the pump shell, an impeller and a shaft sealing assembly, wherein the impeller comprises an impeller web and impeller blades on the front side of the impeller web, the back of the impeller web, the inner wall of the pump shell, the front end face of the shaft seal and the outer peripheral face of a shaft sleeve of the main shaft surround a liquid storage cavity, at least one liquid through hole is axially formed in a plate body of the impeller web and penetrates through the liquid storage cavity and an inner cavity of the pump shell, the improved centrifugal pump is characterized in that radial convex strips are arranged on the back of the impeller web around the circle center, channels between the adjacent convex strips form an open pressure reduction flow channel, the pressure reduction flow channel penetrates through the liquid storage cavity and the inner cavity of the pump shell, a liquid separation cylinder sleeve is arranged on the periphery of a shaft sleeve section in the liquid storage cavity, and the liquid separation cylinder sleeve is fixedly connected with the pump body.

2. An improved centrifugal pump without water cooling as set forth in claim 1, wherein the outer periphery of the sleeve portion of the main shaft sleeve located in the liquid storage chamber is provided with a ridge I inclined to the impeller side.

3. An improved centrifugal pump without water cooling as claimed in claim 1, wherein the inner wall of the liquid separation barrel casing is provided with a second convex line inclined to one side of the impeller.

4. An improved centrifugal pump without water cooling as claimed in claim 2 or 3 wherein the ridge one or two inclined to the impeller side is a trapezoidal thread or a double start thread.

5. An improved centrifugal pump without water cooling as claimed in claim 1, wherein the improved centrifugal pump without water cooling is characterized in that a backflow hole is formed in the wall of the sleeve of the liquid separation barrel, one end of the backflow hole penetrates through the front end face of the shaft seal, and the other end of the backflow hole penetrates through the liquid storage cavity.

6. An improved centrifugal pump which does not require water cooling as set forth in claim 1 wherein the shaft seal assembly comprises a shaft seal which is a lip seal or a mechanical seal or a combination thereof.

7. The improved centrifugal pump without water cooling as claimed in claim 1 wherein the rear side of the shaft seal assembly is provided with a wind wheel.

8. An improved centrifugal pump without water cooling as claimed in claim 1, wherein the centrifugal pump is a front suction centrifugal pump, a side suction centrifugal pump, a horizontal centrifugal pump, or a vertical centrifugal pump.

9. An improved centrifugal pump without water cooling as claimed in any one of claims 1-3, 5-7 wherein the impeller is a semi-open impeller or a shrouded impeller or a semi-open impeller with a ported ring.

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