Corrosion-resistant, wear-resistant, high-sealing performance, long-life water pump mouth ring sealing device

Abstract

The present invention relates to a water pump sealing device, and in particular to a long-life water pump port ring sealing device with corrosion resistance, wear resistance and high sealing performance. The water inlet end of the impeller is the low-pressure end, and a buffer is formed between the low-pressure end of the sealing gap and the water inlet end of the impeller through a pressure relief gap and a pressure buffer cavity. The pressure values ​​are arranged in the order of the high-pressure end of the sealing gap > the pressure buffer cavity (the low-pressure end of the sealing gap) > the water inlet end of the impeller, thereby reducing the pressure difference between the high-pressure end of the sealing gap and the low-pressure end of the sealing gap, reducing the flow rate, and thus reducing the volume loss.

Description

Technical Field

[0001] The invention relates to a water pump sealing device, in particular to a water pump mouth ring sealing device with corrosion resistance, wear resistance and high sealing performance and long service life. Background Art

[0002] The water pump mouth ring seal refers to a sealing device installed between the impeller inlet and the pump body. It is a seal between the high-pressure chamber and the low-pressure chamber, reducing volume loss and improving the efficiency of the water pump. It is mainly used in centrifugal pumps.

[0003] The existing water pump mouth ring seal mainly includes the impeller mouth ring fixed on the impeller, and the pump body mouth ring fixed on the pump body mouth ring. There is a sealing gap between the impeller mouth ring and the pump body mouth ring to avoid friction loss during the operation of the pump. The sealing gap is usually 0.25-1mm. The sealing gap of water pumps with large flow and low head is larger.

[0004] The matching forms between the impeller mouth ring and the pump body mouth ring mainly include parallel type and labyrinth type, such as Figure 1-2 As shown, the parallel structure is simple and easy to install, but has high requirements for installation accuracy. The labyrinth structure can extend the length of the sealing gap, thereby improving the sealing effect and making up for the deficiency in the sealing gap width, but the installation is troublesome. Since the gap between the impeller mouth ring and the pump body mouth ring is small and relative movement occurs, the impeller mouth ring and the pump body mouth ring need to be made of corrosion-resistant, wear-resistant, high-sealing performance and long-life materials. The existing corrosion-resistant, wear-resistant, high-sealing performance and long-life impeller mouth rings and corrosion-resistant, wear-resistant, high-sealing performance and long-life pump body mouth rings mainly use corrosion-resistant, wear-resistant, high-sealing performance and long-life alloys or polymer materials, among which alloys include stainless steel, carbon steel or cast iron. Stainless steel itself has good corrosion resistance, wear resistance, high sealing performance and long life. For carbon steel and cast iron, coating is also performed, for example, Ni60-WC metal ceramic powder laser cladding, etc. Polymer materials include polytetrafluoroethylene, carbon fiber reinforced polyimide composite materials, etc. The bacteria have good corrosion resistance, wear resistance, high sealing performance and long life, thereby obtaining a corrosion-resistant, wear-resistant, high sealing performance and long-life water pump mouth ring sealing device.

[0005] In order to better achieve the seal between the impeller mouth ring and the pump body mouth ring, technicians in this field have studied the matching structure of the impeller mouth ring and the pump body mouth ring, and made better choices of materials, so that the water pump mouth ring sealing device can achieve better results.

[0006] The present invention reduces the pressure difference between the high-pressure end and the low-pressure end of the sealing gap by controlling the pressure at the high-pressure end and the low-pressure end of the sealing gap, thereby improving the sealing effect and reducing volume loss. Summary of the Invention

[0007] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a water pump mouth ring sealing device with corrosion resistance, wear resistance, high sealing performance and long life, which controls the pressure at the high-pressure end and the low-pressure end of the sealing gap, reduces the pressure difference between the high-pressure end and the low-pressure end of the sealing gap, improves the sealing effect, and reduces volume loss.

[0008] The present invention is achieved through the following technical solutions: a corrosion-resistant, wear-resistant, high-sealing-performance, long-life water pump mouth ring sealing device, including a corrosion-resistant, wear-resistant, high-sealing-performance, long-life impeller mouth ring, and a corrosion-resistant, wear-resistant, high-sealing-performance, long-life pump body mouth ring, there is a sealing gap between the impeller mouth ring and the pump body mouth ring, a pressure buffer chamber is provided between the pump body and the impeller at the low-pressure end of the sealing gap, the pressure buffer chamber is connected to the sealing gap, and a pressure relief gap is provided between the side wall of the pressure buffer chamber and the water inlet end of the impeller.

[0009] Furthermore, the width of the pressure relief gap is 1-2 mm.

[0010] Furthermore, an auxiliary sealing ring for cooperating with the pressure relief gap is provided at the low-pressure end of the impeller ring, the auxiliary sealing ring extends into the pressure buffer cavity, and a reflux gap is provided between the auxiliary sealing ring and the pressure buffer cavity.

[0011] Furthermore, the width of the reflux gap is 1-2 mm.

[0012] Furthermore, a plurality of pressure transfer holes are evenly arranged on the auxiliary sealing ring, and the pressure transfer holes are radially distributed on the auxiliary sealing ring.

[0013] Furthermore, a pump body mouth ring installation groove is provided on the pump body, and the pump body mouth ring is arranged in the pump body mouth ring installation groove.

[0014] The beneficial effects of the present invention are: a corrosion-resistant, wear-resistant, high-sealing-performance, long-life water pump mouth ring sealing device, comprising a corrosion-resistant, wear-resistant, high-sealing-performance, long-life impeller mouth ring, and a corrosion-resistant, wear-resistant, high-sealing-performance, long-life pump body mouth ring, a sealing gap is provided between the impeller mouth ring and the pump body mouth ring, a pressure buffer chamber is provided between the pump body and the impeller at the low-pressure end of the sealing gap, the pressure buffer chamber is communicated with the sealing gap, a pressure relief gap is provided between the side wall of the pressure buffer chamber and the impeller water inlet end, the water inlet end of the impeller is the low-pressure end, and the low-pressure end of the sealing gap and the water inlet end of the impeller are buffered by the pressure relief gap and the pressure buffer chamber, the pressure values ​​are arranged as the sealing gap high-pressure end>pressure buffer chamber (sealing gap low-pressure end)>impeller water inlet end, thereby reducing the pressure difference between the sealing gap high-pressure end and the sealing gap low-pressure end, reducing the flow rate, and thereby reducing the volume loss. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a schematic diagram of the parallel water pump mouth ring seal structure;

[0016] Figure 2 This is a schematic diagram of the labyrinth water pump mouth ring seal structure;

[0017] Figure 3 This is a schematic diagram of the installation position of the water pump mouth ring sealing structure;

[0018] Figure 4 This is a partial enlarged view of Example 1A;

[0019] Figure 5 This is a partial enlarged view of Example 2A;

[0020] Figure 6 This is a schematic diagram of the impeller ring structure of Example 3.

[0021] Figure 7 Schematic cross-sectional view of the impeller port ring and pump port ring of Example 4;

[0022] Among them: 1. Impeller; 2. Impeller mouth ring; 3. Pump body mouth ring; 4. Sealing gap; 5. Pump body; 6. Pressure buffer chamber; 7. Pressure relief gap; 8. Auxiliary sealing ring; 9. Pressure transfer hole; 10. Return gap. DETAILED DESCRIPTION

[0023] In the description of the present invention, it should also be noted that, unless otherwise expressly specified or limited, the terms "disposed," "installed," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; they may refer to mechanical connections or electrical connections; they may refer to direct connections or indirect connections through an intermediate medium; and they may refer to internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0024] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0025] Example 1

[0026] like Figure 3-4As shown, a corrosion-resistant, wear-resistant, high-sealing performance and long-life water pump mouth ring sealing device comprises a corrosion-resistant, wear-resistant, high-sealing performance and long-life impeller mouth ring 2, and a corrosion-resistant, wear-resistant, high-sealing performance and long-life pump body mouth ring 3. There is a sealing gap between the impeller mouth ring and the pump body mouth ring. In this embodiment, the corrosion-resistant, wear-resistant, high-sealing performance and long-life impeller mouth ring is made of 316 stainless steel, is precision-cast and formed, and then fine-machined to obtain an impeller mouth ring of a predetermined size. The impeller mouth ring is installed with the impeller 1 by means of interference fit, and can be fixed with auxiliary welding or without welding. The corrosion-resistant, wear-resistant, high-sealing performance and long-life pump body mouth ring is made of 316 stainless steel, is precision-cast and formed, and then fine-machined to obtain an impeller mouth ring of a predetermined size. After fine machining, a pump body mouth ring of a predetermined size is obtained. The pump body mouth ring is installed with the pump body 5 by means of interference fit, and can be fixed with auxiliary welding or without welding. A pump body mouth ring mounting groove that matches the pump body mouth ring is processed on the pump body. The inner wall of the pump body mouth ring exceeds the pump body mouth ring mounting groove by 0-1mm. There is a sealing gap 4 between the impeller mouth ring and the pump body mouth ring. The sealing gap is 0.25-0.75mm. The high-pressure end of the sealing gap is connected to the outlet end of the impeller, and the low-pressure end of the sealing gap is connected to the inlet end of the impeller. During the rotation of the impeller, water flows from the inlet end to the outlet end in the impeller. Under the action of the pressure difference, the water at the sealing gap flows from the high-pressure end to the low-pressure end, resulting in volume loss and reducing the efficiency of the water pump.

[0027] In order to reduce the pressure difference between the high-pressure end and the low-pressure end of the sealing gap, a pressure buffer chamber 6 is processed at the low-pressure end of the sealing gap between the pump body and the impeller. The pressure buffer chamber is connected to the sealing gap, and a pressure relief gap 7 is provided between the side wall of the pressure buffer chamber and the water inlet end of the impeller. Specifically, a sink groove matching the impeller inlet end is processed on the pump body, a pump body mouth ring mounting groove is processed on the side wall of the sink groove, and a groove is processed on the bottom of the sink groove. The groove and the impeller inlet end face cooperate to form a pressure buffer chamber. The size of the pressure buffer chamber is based on not affecting the structural strength of the pump body. The larger the volume, the better the pressure buffering effect. Through casting, in this embodiment, taking the ZA25-200 centrifugal pump as an example, the groove depth is 10mm and the width is 6mm, which can ensure the stability of the pump body and obtain a larger pressure buffer chamber volume. The width of the pressure relief gap is 1-2mm, which is 1.5mm in this embodiment, so that there is a larger gap between the bottom surface of the sink groove and the end face of the impeller water inlet end, thereby avoiding collision / friction during axial movement of the impeller.

[0028] During the operation of the centrifugal pump, due to the action of centrifugal force, water flows from the water inlet end to the water outlet end inside the impeller. The water pressure at the water inlet end is low and the water pressure at the water outlet end is high. In the existing parallel mouth ring sealing device, the high-pressure end of the sealing gap is directly connected to the water outlet end, and the low-pressure end is directly connected to the water inlet end. The pressure difference between the high-pressure end and the low-pressure end is large, and the water flow through the sealing gap is large. In this embodiment, a pressure buffer chamber is introduced, and a pressure relief gap is provided between the side wall of the pressure buffer chamber and the water inlet end of the impeller, thereby preventing the sealing gap from being directly connected to the water inlet end of the impeller. The outer diameter value of the pressure relief gap is smaller than the outer diameter value of the pressure relief gap. When the width value of the pressure relief gap is larger than the sealing gap, When the width value is set, the difference in water flow cross-sectional area is small. During the operation of the water pump, the pressure values ​​are ranked as follows: high-pressure end of the sealing gap > pressure buffer chamber (low-pressure end of the sealing gap) > impeller water inlet end. Since the pressure buffer chamber has a large volume, it is connected to the impeller water inlet end through the pressure relief gap, causing a delay in water pressure reduction, thereby making the pressure at the low-pressure end of the sealing gap greater than the pressure at the impeller water inlet end. The water flow through the sealing gap is reduced, and the impact on the water pressure of the pressure buffer chamber is reduced, thereby causing the water pressure difference between the pressure buffer chamber and the impeller water inlet end to increase and be buffered. The pressure is released through the pressure relief gap to achieve balance, thereby achieving the purpose of reducing water outflow from the sealing gap and reducing volume loss.

[0029] Example 2

[0030] like Figure 5 As shown, a corrosion-resistant, wear-resistant, high-sealing performance, long-life water pump mouth ring sealing device is different from Example 1 in that the low-pressure end of the impeller mouth ring 2 is integrally formed with an auxiliary sealing ring 8 for cooperating with the pressure relief gap 7. The auxiliary sealing ring extends into the pressure buffer chamber. There is a reflux gap 10 between the auxiliary sealing ring and the pressure buffer chamber. The width of the reflux gap is 1-2mm, which is 1mm in this embodiment. The width of the reflux gap is slightly larger than the width of the sealing gap. During the rotation of the impeller, the radial runout amplitude is smaller than the width of the sealing gap, so that no collision / friction occurs between the auxiliary sealing ring and the side wall of the pressure buffer chamber. Through the cooperation of the reflux gap and the pressure relief gap, the length of the narrow flow channel between the pressure buffer chamber and the impeller inlet is increased, and at the same time, the water flow area is reduced, thereby reducing the pressure reduction rate of the pressure buffer chamber. In the equilibrium state, the pressure in the pressure buffer chamber is further increased, thereby further reducing water outflow from the sealing gap and reducing volume loss.

[0031] Example 3

[0032] like Figure 6As shown, a corrosion-resistant, wear-resistant, high-sealing performance and long-life water pump mouth ring sealing device is different from Example 2 in that a plurality of pressure transfer holes 9 are evenly processed on the auxiliary sealing ring 8, and the pressure transfer holes are radially distributed on the auxiliary sealing ring. When the auxiliary sealing ring rotates with the impeller, due to the action of centrifugal force, the water flow in the pressure transfer hole moves from the inner end to the outer end, thereby increasing the water pressure at the outer end of the pressure transfer hole. The outer end of the pressure transfer hole corresponds to the low-pressure end of the sealing gap, which increases the water pressure at the low-pressure end, thereby reducing the pressure difference between the high-pressure end and the low-pressure end of the sealing gap, thereby further reducing the water outflow from the sealing gap and reducing the volume loss.

[0033] Example 4

[0034] like Figure 7 As shown, a corrosion-resistant, wear-resistant, high-sealing performance, long-life water pump mouth ring sealing device is shown. Unlike Example 1, the impeller mouth ring 2 or the pump body mouth ring 3 uses aramid packing. In this embodiment, the pump body mouth ring 3 uses aramid packing. Aramid packing is woven from aramid fiber impregnated with polytetrafluoroethylene emulsion and treated with a lubricant. It has good chemical resistance, high resilience, and low cold flow. Specifically, aramid fiber packing numbered GX3-2 from Dacheng County Guangxin Insulation Material Factory can be used. A sealing gap is formed between the pump body mouth ring and the impeller mouth ring formed by the aramid packing. The impeller mouth ring is a stainless steel ring. The hardness of the pump body mouth ring is lower than that of the impeller mouth ring. No rigid collision will occur during rotation. It can be used with a smaller sealing gap width, thereby improving the sealing effect.

[0035] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A corrosion-resistant, wear-resistant, high-sealing performance, long-life water pump mouth ring sealing device, comprising a corrosion-resistant, wear-resistant, high-sealing performance, long-life impeller mouth ring, and a corrosion-resistant, wear-resistant, high-sealing performance, long-life pump body mouth ring, a sealing gap is provided between the impeller mouth ring and the pump body mouth ring, characterized in that: A pressure buffer chamber is provided between the pump body and the impeller at the low-pressure end of the sealing gap. The pressure buffer chamber is communicated with the sealing gap, and a pressure relief gap is provided between the side wall of the pressure buffer chamber and the water inlet end of the impeller. The low-pressure end of the impeller ring is provided with an auxiliary sealing ring for cooperating with the pressure relief gap. The auxiliary sealing ring extends into the pressure buffer cavity. A reflux gap is provided between the auxiliary sealing ring and the pressure buffer cavity. The width of the reflux gap is 1-2 mm, and the sealing gap is 0.25-0.75 mm. The width of the reflux gap is slightly larger than the width of the sealing gap. By coordinating the reflux gap with the pressure relief gap, the length of the narrow flow channel between the pressure buffer chamber and the impeller inlet is increased, while the water flow area is reduced, thereby reducing the pressure reduction speed of the pressure buffer chamber. A plurality of pressure transfer holes are evenly arranged on the auxiliary sealing ring, and the pressure transfer holes are radially distributed on the auxiliary sealing ring. When the auxiliary sealing ring rotates with the impeller, due to the action of centrifugal force, the water flow in the pressure transfer hole moves from the inner end to the outer end, thereby increasing the water pressure at the outer end of the pressure transfer hole. The outer end of the pressure transfer hole corresponds to the low-pressure end of the sealing gap, which increases the water pressure at the low-pressure end, thereby reducing the pressure difference between the high-pressure end and the low-pressure end of the sealing gap.

2. The corrosion-resistant, wear-resistant, high-sealing performance and long-life water pump mouth ring sealing device according to claim 1 is characterized in that: The width of the pressure relief gap is 1-2 mm.

3. The corrosion-resistant, wear-resistant, high-sealing performance and long-life water pump mouth ring sealing device according to claim 1 is characterized in that: The pump body is provided with a pump body mouth ring installation groove, and the pump body mouth ring is arranged in the pump body mouth ring installation groove.

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