Built-in liquid ring type vacuum pump deslagging device

Abstract

The utility model relates to a built-in liquid ring type vacuum pump deslagging device, which belongs to the field of vacuum pump operation, and comprises a deslagging long strip hole, a deslagging round hole, a pump body inner wall, an air suction hole, an exhaust hole, a deslagging pipe, a disc, a pump cover and a discharge port, the air suction hole is a semi-crescent hole, a working liquid inlet is a long strip hole, and the exhaust hole is a triangular hole. A plurality of flexible exhaust holes are formed in the disc, the flexible exhaust holes are all rounded rectangular air holes, slag discharging holes are formed in the disc, the slag discharging holes are long-strip-shaped or round, and the long-strip-shaped slag discharging holes or the round slag discharging holes are communicated with working fluid in the pump and a pump cover discharging opening through slag discharging pipes; the structure is simple, durability is good, and damage is not prone to occurring; maintenance is avoided, no part is added, the investment is minimum, and the output is maximum; the achieved effect is quite obvious, and the investment can be neglected relative to the price of the pump body, the disc and the impeller part.

Description

Technical Field

[0001] The utility model relates to a slag discharge device of a built-in liquid ring vacuum pump, belonging to the field of vacuum pump operation. Background Art

[0002] The design, manufacture and use of liquid ring pumps have a history of nearly a hundred years. Liquid ring vacuum pumps / compressors are widely used due to their simple structure, low manufacturing requirements, stable performance, reliable operation, easy maintenance, low noise, and large-scale manufacturing.

[0003] At present, there are only two main structural forms of liquid ring pumps in the world, namely single-acting and double-acting liquid ring pumps. The positions of the suction and exhaust ports of both are within the cavity range close to the axis position (within the liquid ring limit). Since the eccentric design requirements must be met (the working principle of the liquid ring pump), on the suction side, as the pump body and the hub that constrain the liquid gradually move away, the liquid ring is thrown out, the cavity changes from small to large, the pressure decreases, and the gas is introduced from the suction port set within the cavity range, thereby inhaling. On the compression side, as the pump body and the hub gradually approach each other, the cavity changes from large to small, and the pressure of the gas constrained therein increases. When it is greater than the external pressure, the gas is led out from the exhaust port located within the liquid ring interface range, thereby exhausting.

[0004] The pump body of the liquid ring vacuum pump and the disc (or end cover) at the end face of the impeller constitute the constraint mechanism of the liquid ring. The liquid ring rotates in the constraint mechanism driven by the impeller. The inner surface of the liquid ring periodically approaches or moves away from the hub. The liquid is always in the outer ring and the gas is in the inner ring. The suction and exhaust ports must be opened within the cavity range of the liquid ring interface. If the range is exceeded and the liquid overflows, the liquid ring becomes thinner, which will lead to insufficient suction and incomplete exhaust, thus affecting the efficiency of the pump, so it is not feasible.

[0005] Due to the above structural characteristics, welding slag accidentally introduced during the installation of the pump, dust and particles entering with the gas, sand entering with the working fluid, scale and crystals accumulated in the pump, and other solid substances with a density greater than the working fluid (hereinafter referred to as slag) cannot be discharged from the pump during operation. In many processes, the pump is required to work continuously for a long time. The wear of the pump body and disc by this part of the slag rotating at high speed with the liquid ring is inevitable. Some substances will also scale on the surface of the pump body and the disc, increasing the resistance to the rotation of the liquid ring and increasing power consumption. In particular, it continues to accumulate at the exhaust port, occupying the effective exhaust channel, resulting in poor exhaust, reduced gas volume, and increased motor power consumption. A large number of cases have proved that the reduced efficiency of the vacuum pump and the damage of components are closely related to the above situation. For example, in the processes of vacuum conveying of fly ash, vacuum conveying of sand, dry aluminum fluoride, catalyst regeneration in the PVC industry, vacuum casting, etc., the above situation exists in large quantities.

[0006] Even during the pump shutdown period, liquid ring pump damage is rarely discovered or resolved in the early stages due to personnel shortages, inadequate equipment management, unclear equipment damage, increased vacuum pump power consumption and slow decline in efficiency, and self-compensation of liquid ring pump parts after wear.

[0007] In view of the above situation, the more common solutions in the existing vacuum system are as follows: 1. Install a separation device or a blocking device at the entrance of the vacuum system according to the characteristics of the material, such as: a cyclone separator, a pulse bag dust collector, a vacuum buffer tank, a filter, a filter screen, etc. 2. Install a filter on the water supply side of the vacuum system, such as: a basket filter, a mesh filter, etc. 3. Open a flushing port at the lowest part of the pump body.

[0008] Although the above devices can solve some problems to a large extent, there are still many problems. The reasons are unreasonable setting of the filter device, inadequate equipment management, insufficient management personnel, insufficient experience, untimely replacement and cleaning of the filter device, and working conditions that do not allow. For example, in the fly ash transportation process in vacuum smelting, a pulse bag dust removal device is generally installed at the entrance of the system. However, due to the wide distribution of the particle size of the transported material, there are always dust particles smaller than the mesh of the filter cloth, bagging damage, and leakage of the sealing device. The density of this dust is greater than that of water. After enrichment in the pump, it agglomerates into larger particles, causing damage to the pump. Another example: in the dry aluminum fluoride process, the inhaled hydrogen fluoride gas reacts with the alkali solution in the working fluid (added to neutralize the pH of the working fluid) to generate sodium fluoride crystals, which crystallize in the pump. The flushing port at the bottom of the vacuum pump has a small diameter, and the flushing effect is very limited by relying on the self-flow of the working fluid retained in the pump, and in many cases, the discharge of the working fluid is not allowed.

[0009] Therefore, it is inevitable that materials will enter the pump, resulting in efficiency loss and component damage. Disassembly and cleaning and component replacement are almost the only solutions, and the cost of downtime and component damage is huge. Utility Model Content

[0010] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0011] A built-in liquid ring vacuum pump slag discharge device comprises a disc, a pump cover and a pump body, wherein the disc is provided with an air suction hole, a working fluid inlet, a flexible exhaust hole and an exhaust hole, wherein the air suction hole is a semi-crescent-shaped hole, the working fluid inlet is a long strip opening, and the exhaust hole is a triangular hole, wherein seven to ten flexible exhaust holes are provided on the disc, wherein the flexible exhaust holes are all rounded rectangular air holes, and the disc is provided with a slag discharge hole, wherein the slag discharge hole is a long strip or a circle, and the slag discharge long strip hole or the slag discharge circular hole is connected to the working fluid in the pump and the discharge port of the pump cover through a slag discharge pipe, and the slag is discharged into the exhaust pipeline through the outer layer working fluid with the highest slag content of the partial drainage liquid ring, thereby achieving the purpose of slag discharge.

[0012] As a further solution of the utility model: the shape and size of the slag discharge hole depends on the size of the pump and the amount of slag contained. A strip or circular hole is used, and the outer edge of the hole wall is close to the inner surface of the pump body, the purpose is to drain the outermost layer of liquid in the liquid ring.

[0013] As a further solution of the utility model: one end of the slag discharge pipe is connected to the slag discharge hole, and the other end is connected to the inside of the pump cover, and the flow is drained downward through the elbow.

[0014] As a further solution of the utility model: the compression side of the entire disc can be used as the opening position of the slag discharge hole, and the water pressure at the opening position is greater than the exhaust pressure of the pump.

[0015] As a further solution of the utility model: the hole wall material of the slag discharge hole should be selected from wear-resistant and corrosion-resistant materials according to requirements.

[0016] Compared with the prior art, the utility model has the following beneficial effects:

[0017] 1. The structure is extremely simple, durable and not easy to damage.

[0018] 2. Maintenance-free: No additional parts are required and the pump structure is not changed, so no maintenance is required.

[0019] 3. Efficient separation, good effect; the working fluid (outermost side of the liquid ring) drawn out from the pump body has the maximum concentration of particles, so the separation efficiency is the highest, and its effectiveness has been proven by experiments.

[0020] 4. Minimum investment and maximum output; with nearly zero investment, the effect achieved is quite obvious. Compared with the price of pump body, disc and impeller parts, the investment is negligible. Compared with the loss of production suspension and maintenance labor cost, the investment is also negligible. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a schematic diagram of the slag discharge opening of the utility model;

[0022] Figure 2 This is a schematic diagram of the installation of the slag discharge pipe of the utility model;

[0023] Figure 3 This is the installation diagram of the disc and pump cover of the utility model.

[0024] Notes on figure numbers: 1. Long strip hole for slag discharge; 2. Round hole for slag discharge; 3. Inner wall of pump body; 4. Air intake hole; 5. Air exhaust hole; 6. Slag discharge pipe; 7. Disc; 8. Pump cover; 9. Discharge port; 10. Pump chamber. DETAILED DESCRIPTION

[0025] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0026] By drilling holes in the compression side of the disc, the liquid and slag are discharged to the discharge port of the pump, and the dynamic removal of the slag in the pump is achieved in the simplest way. Its feasibility is based on the process method of self-flow of the working fluid based on the pressure difference when the pressure of the exhaust liquid ring in the pump body is greater than the pressure of the exhaust port. It is the result of in-depth research on the characteristics and structure of the liquid ring and the result of innovative thinking.

[0027] The built-in liquid ring vacuum pump slag discharge device is composed of a slag discharge long strip hole 1, a slag discharge circular hole 2, a pump body inner wall 3, an air suction hole 4, an exhaust hole 5, a slag discharge pipe 6, a disc 7, a pump cover 8, and a discharge port 9. The disc 7 is provided with a slag discharge long strip hole 1, and the slag discharge long strip hole 1 and the slag discharge circular hole 2 are a two-or-one structure. The slag discharge long strip hole 1 or the slag discharge circular hole 2 is connected to the slag discharge pipe 6. The working fluid containing slag is discharged into the cavity between the pump cover 8 and the disc 7 through the slag discharge hole 1 and the slag discharge pipe 6, and is discharged to the outside of the pump through the pump discharge port together with the working fluid and gas discharged from the exhaust hole 5.

[0028] The position, diameter and number of the slag discharge strip hole 1 or the slag discharge circular hole 2 are determined by the size of the pump, the type of slag, the influence of the holes on the strength of the pump body and other factors; including single-acting liquid ring vacuum pumps (single-acting flat disc liquid ring vacuum pumps, single-acting cone liquid ring vacuum pumps), double-acting liquid ring vacuum pumps (double-acting flat disc liquid ring vacuum pumps, double-acting cone liquid ring vacuum pumps), liquid ring compressor products of the above structural forms (liquid ring vacuum pumps with variable purposes), and deformed products of the above structural forms.

[0029] The slag discharge hole is drilled on the exhaust side of the disc close to the inner edge of the pump body. The aperture shape and aperture area determine the slag discharge effect. Part of the working fluid is extracted from the outermost layer of the liquid ring (i.e. the inner surface of the pump body) for discharge. The density of the slag is greater than that of the working fluid. Under the action of centrifugal force, the principle of centrifugal separation is used to extract the liquid with the highest slag content for discharge, which has the best slag discharge effect. The size and shape of the hole depend on the process conditions.

[0030] The liquid is drained downward through the conduit to protect the pump cover from damage due to long-term jet action; since the high-speed and debris-containing fluid will have a significant scouring effect on the wall of the aperture (the flow-facing surface) after flowing through the opening position, causing the aperture to expand (in the direction of fluid flow, similar to the wake effect), it is necessary to adopt measures such as sleeve wear-resistant materials, thickening the thickness of the hole wall (thickening the outer layer of the pump body) in advance to reinforce the pump body, while ensuring the strength of the pump body and extending the service life of the pump body.

[0031] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A slag discharge device for a built-in liquid ring vacuum pump, comprising a disc (7) and a pump cover (8), wherein the disc (7) is disc-shaped, and the pump cover (8) is connected to the disc (7), characterized in that: The built-in liquid ring vacuum pump slag discharge device is composed of a slag discharge long strip hole (1), a slag discharge round hole (2), an inner wall of a pump body (3), an air suction hole (4), an air discharge hole (5), a slag discharge pipe (6), a disc (7), a pump cover (8), and a discharge port (9); The slag discharge strip hole (1) is arranged on the outside of the disc (7), and the slag discharge circular hole (2) is arranged on the inside of the disc (7). The disc (7) is provided with an air intake hole (4) on the air intake side and an air exhaust hole (5) on the compression side. The air intake hole (4) is in a semi-crescent shape, and the air exhaust hole (5) is in a triangular shape. The disc (7) is provided with a plurality of flexible air exhaust holes. The air intake hole (4), the air exhaust hole (5) and the plurality of flexible air exhaust holes are distributed on the disc (7) with the inner wall of the pump body as the center. One end of the slag discharge pipe (6) is connected to the slag discharge circular hole (2), and the other end is connected to the pump cavity (10). The pump cavity (10) is connected to the discharge port (9) of the pump cover.

2. A slag discharge device with a built-in liquid ring vacuum pump according to claim 1, characterized in that: A slag discharge long strip hole (1) or a slag discharge circular hole (2) is provided at the intersection of the compression side of the disc (7) and the inner wall (3) of the pump body.

3. A slag discharge device with a built-in liquid ring vacuum pump according to claim 1, characterized in that: One end of the slag discharge pipe (6) is connected to the slag discharge long hole (1) or the slag discharge circular hole (2), and the other end is connected to the inside of the pump cover (8), and the pipe mouth of the slag discharge pipe (6) faces the center of the disc (7).

4. The slag discharge device with a built-in liquid ring vacuum pump according to claim 1, characterized in that: The slag discharge long strip hole (1) or the slag discharge round hole (2) is connected to the working fluid in the pump and the discharge port (9) of the pump cover through the slag discharge pipe (6).

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