Solid particle reduction structure for sealed cavity

Abstract

The solid particle reduction structure comprises a machine shell, the sealing cavity is formed in the machine shell, a mechanical sealing structure is arranged at the first end, located in the sealing cavity, of the machine shell, and a shaft hole communicated with the sealing cavity is formed in the second end of the machine shell; the rotating shaft penetrates through the sealing cavity in the axial direction and penetrates out of the shaft hole, and a gap is formed between the rotating shaft and the inner wall of the shaft hole; the axial pushing structure is arranged on the rotating shaft, located in the sealing cavity and used for applying axial pushing force from the mechanical sealing structure to the shaft hole direction to a medium in the sealing cavity when rotating along with the rotating shaft. According to the solid particle reduction structure, reduction of solid particles moving near a mechanical sealing structure and discharging of the solid particles in a sealing cavity can be achieved, the working environment of the mechanical sealing structure is improved, the abrasion and damage speed of the mechanical sealing structure is reduced, and the service life of the mechanical sealing structure is prolonged; and the maintenance time and cost of pump products are greatly reduced.

Description

Technical Field

[0001] This application relates to the technical field of fluid machinery and engineering equipment, and particularly to a solid particle reduction structure for a sealing cavity. Background Art

[0002] Mechanical seals (referred to as "shaft seals" for short), as an efficient sealing technology, are widely used in equipment such as centrifugal pumps and reactors. When these devices operate in an environment with poor water quality, solid particles such as sediment and stones in the liquid often enter the sealing cavity. These solid particles move in the cavity along with the water flow, frequently collide with the surface of the shaft seal parts, forming a frictional effect, which easily causes wear of the mechanical seal. Moreover, when the solid particles swim near the friction pair of the shaft seal, they may enter the friction surface, resulting in leakage of the shaft seal failure. Therefore, it is necessary to clean the solid particles in the sealing cavity.

[0003] Currently, the solid particles in the sealing cavity are mainly discharged from the annular gap between the sealing cavity and the rotating shaft (or shaft sleeve) along with the shaft seal flushing water to achieve the cleaning purpose. However, the discharge efficiency of this method is low, and the discharge effect is not ideal, resulting in some solid particles being easily precipitated and accumulated at the bottom of the sealing cavity. Also, due to the height difference between the annular gap and the bottom of the cavity, the particles below the annular gap are difficult to be discharged from the cavity, so that these solid particles will remain in the sealing cavity, which is likely to cause damage to the mechanical seal. Utility Model Content

[0004] Based on this, the present utility model provides a solid particle reduction structure for a sealing cavity to solve the problem in the prior art that solid particles are likely to remain in the sealing cavity and have an adverse effect on the mechanical seal.

[0005] On the one hand, the present utility model provides a solid particle reduction structure for a sealing cavity, which includes:

[0006] A casing, the sealing cavity is arranged inside the casing. The casing is provided with a mechanical seal structure at the first end of the sealing cavity and a shaft hole communicating with the sealing cavity at the second end.

[0007] A rotating shaft, the rotating shaft axially penetrates through the sealing cavity and passes out from the shaft hole. There is a gap between the rotating shaft and the inner wall of the shaft hole.

[0008] An axial pushing structure, the axial pushing structure is arranged on the rotating shaft and located inside the sealing cavity, and is used to apply an axial driving force in the direction from the mechanical seal structure to the shaft hole to the medium in the sealing cavity when the rotating shaft rotates.

[0009] In one embodiment, a flow guiding surface is provided in the sealing cavity. The flow guiding surface extends at least from the inner wall of the sealing cavity below the shaft hole to the shaft hole, and the included angle between the flow guiding surface and the inner wall of the sealing cavity is an obtuse angle.

[0010] In one embodiment, the flow guiding surface is circumferentially connected between the inner wall of the shaft hole and the inner wall of the sealing cavity.

[0011] In one embodiment, the flow guiding surface is a conical surface.

[0012] In one embodiment, the included angle between the flow guiding surface and the inner wall of the sealing cavity is greater than or equal to 120 degrees.

[0013] In one embodiment, the axial pushing structure is arranged between the mechanical seal structure and the junction of the flow guiding surface and the inner wall of the sealing cavity.

[0014] In one embodiment, the axial pushing structure is located on one side of the sealing cavity close to the mechanical seal structure.

[0015] In one embodiment, the rotational diameter of the axial pushing structure rotating with the rotating shaft is more than three-quarters of the diameter of the sealing cavity.

[0016] In one embodiment, the axial pushing structure includes an axial flow impeller or a spiral blade.

[0017] In one embodiment, a flushing water inlet pipe is provided on the mechanical seal structure, and the flushing water inlet pipe is communicated with the sealing cavity.

[0018] The utility model has at least the following beneficial effects compared with the prior art:

[0019] In this solid particle reduction structure, by arranging an axial pushing structure on the rotating shaft, when the axial pushing structure rotates with the rotating shaft, an axial pushing force from the mechanical seal structure to the shaft hole direction can be applied to the medium and solid particles in the sealing cavity, thereby realizing the reduction of solid particles wandering near the mechanical seal structure and the discharge of solid particles in the sealing cavity, improving the working environment of the mechanical seal, reducing the abrasion and damage speed of the mechanical seal, prolonging the service life of the mechanical seal, and greatly reducing the maintenance time and cost of pump products. Moreover, the mechanical seal structure can also cope with more complex working conditions with ordinary materials without using expensive wear-resistant materials, which can not only reduce the product cost but also expand the application scenarios of pump products, and has better universality. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic structural diagram of a solid particle reduction structure for a sealing cavity in one embodiment.

[0021] The reference numerals in the accompanying drawings of the specification include: the housing 1, the sealing cavity 2, the rotating shaft 3, the shaft hole 4, the axial pushing structure 5, the guiding surface 6, the mechanical seal structure 7, and the flushing water inlet pipe 8. Detailed implementation manners

[0022] In order to make the objectives, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0023] It should be noted that the illustrations provided in this embodiment only schematically illustrate the basic concept of the present utility model.

[0024] The structures, ratios, sizes, etc. shown in the drawings of this specification are only used to cooperate with the content disclosed in the specification for those skilled in this technology to understand and read, and are not used to limit the limiting conditions under which the present utility model can be implemented. Any modification of the structure, change of the proportional relationship or adjustment of the size, without affecting the effects that the present utility model can produce and the objectives that can be achieved, should still fall within the scope covered by the technical content disclosed by the present utility model.

[0025] The orientation or positional relationship indicated by terms such as "upper", "lower", "left", "right", "middle", "longitudinal", "transverse", "horizontal", "inner", "outer", "radial", "circumferential", etc. cited in this specification is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of simplified description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be construed as a limitation on the present utility model. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0026] Currently, the solid particles in the sealing cavity mainly reach the cleaning purpose by being discharged from the annular gap between the sealing cavity and the rotating shaft (or shaft sleeve) along with the random sealing flushing water. However, the discharge efficiency of this method is relatively low, and the discharge effect is not ideal, resulting in more solid particles still accumulating in the sealing cavity, which is likely to damage the mechanical seal.

[0027] In view of this, the embodiment of the present utility model provides a solid particle reduction structure for a sealing cavity, which includes:

[0028] The housing 1, the sealing cavity 2 is arranged inside the housing 1. The housing 1 is provided with a mechanical seal structure 7 at the first end of the sealing cavity 2, and a shaft hole 4 communicating with the sealing cavity 2 at the second end;

[0029] The rotating shaft 3 passes through the sealing cavity 2 in the axial direction and exits from the shaft hole 4. There is a gap between the rotating shaft 3 and the inner wall of the shaft hole 4.

[0030] The axial pushing structure 5 is arranged on the rotating shaft 3 and located inside the sealing cavity 2, and is used to apply an axial pushing force from the mechanical seal structure 7 to the shaft hole 4 to the medium in the sealing cavity 2 when the rotating shaft 3 rotates.

[0031] In the solid particle reduction structure provided by the embodiment of the present utility model, by arranging the axial pushing structure 5 on the part of the rotating shaft 3 located inside the sealing cavity 2, when the rotating shaft 3 rotates, it can drive the axial pushing structure 5 to rotate, and the rotation of the axial pushing structure 5 can apply an axial pushing force from the mechanical seal structure 7 to the shaft hole 4 to the medium in the sealing cavity 2, driving the medium to flow towards the outlet (shaft hole 4) of the sealing cavity 2, that is, making the medium flow away from the mechanical seal structure 7. Correspondingly, the solid particles in the medium will also move away from the mechanical seal structure 7, so as to achieve the purpose of reducing the solid particles wandering near the mechanical seal structure 7 and improving the working environment of the mechanical seal. Moreover, when the axial pushing structure 5 rotates, the flow velocity of the medium in the sealing cavity 2 is increased, exceeding the sedimentation flow velocity of the solid particles, avoiding the occurrence of sedimentation phenomenon, so that the solid particles can be discharged from the shaft hole 4 with the flowing medium from the sealing cavity 2 and do not precipitate and stay in the sealing cavity 2, realizing the reduction and removal of solid particles in the sealing cavity 2.

[0032] In the solid particle reduction structure provided by the embodiment of the present utility model, by arranging the axial pushing structure 5, it is possible to achieve the reduction of the solid particles wandering near the mechanical seal structure 7 and the external discharge of the solid particles in the sealing cavity 2, improve the working environment of the mechanical seal, reduce the abrasion and damage speed of the mechanical seal, extend the service life of the mechanical seal, and greatly reduce the maintenance time and cost of the equipment product. Moreover, the mechanical seal structure 7 can also cope with more complex working conditions by using ordinary materials instead of expensive wear-resistant materials, which can not only reduce the product cost, but also expand the application scenarios of the equipment product and have better universality.

[0033] The following will describe in detail the solid particle reduction structure for the sealing cavity provided by the embodiment of the present utility model with reference to the accompanying drawings.

[0034] It should be noted that the solid particle reduction structure provided in this embodiment can be applied to various rotating fluid mechanical equipment with mechanical seals installed, such as rotor pumps, reaction kettles, etc. The following will only describe it exemplarily with the solid particle reduction structure applied to a rotor pump.

[0035] According to Figure 1An exemplary solid particle reduction structure showing at least one embodiment of the present invention. The solid particle reduction structure for a sealing chamber includes: a housing 1, a rotating shaft 3, and an axial pushing structure 5.

[0036] Among them, the housing 1 is a housing part. In particular, in the solid particle reduction structure provided in this embodiment, which is applied to a rotor pump, the housing 1 is the housing part of a horizontal rotor pump. Depending on different usage environments, installation methods, etc., the housing 1 can be designed into different shapes and structures. Figure 1 Only an exemplary part of the structure of one of the housings 1 is shown.

[0037] The rotating shaft 3 is the rotating shaft of the pump, which is inserted through the housing 1. One end is used to connect to a driving member such as a motor, and the other end is used to connect to the pump impeller to achieve power transmission from the motor to the pump impeller.

[0038] To ensure the sealing of the pump, a sealing structure is also provided between the rotating shaft 3 and the housing 1. Specifically, referring to Figure 1 , a sealing chamber 2 is provided inside the housing 1. In this embodiment, the sealing chamber 2 is a cylindrical cavity. The sealing chamber 2 has a first end and a second end in the axial direction. A mechanical seal structure 7 is provided at the position of the housing 1 at the first end of the sealing chamber 2, and a shaft hole 4 is provided at the position of the housing 1 at the second end of the sealing chamber 2. The rotating shaft 3 is inserted through the sealing chamber 2 in the axial direction. One end is in sealing cooperation with the mechanical seal structure 7 and extends outwards, and the other end extends outwards from the shaft hole 4 to achieve dynamic sealing cooperation between the rotating shaft 3 and the housing 1.

[0039] It should be noted that in this embodiment, the first end of the sealing chamber 2 can be understood as Figure 1 the right end of the sealing chamber 2 in the shown orientation, and the second end of the sealing chamber 2 can be understood as Figure 1 the left end of the sealing chamber 2 in the shown orientation.

[0040] Among them, regarding the mechanical seal structure 7, it is mainly used to achieve dynamic sealing between the rotating shaft 3 and the housing 1, to prevent the fluid medium in the pump volute from flowing out of the pump through the rotating shaft 3. Its specific structure and principle are both prior arts and not the focus of the present invention. Therefore, the structure of it will not be elaborated in this embodiment, and it can be understood with the structure shown in Figure 1 .

[0041] Referring to Figure 1 , a flushing water inlet pipe 8 is also provided on the mechanical seal structure 7. The flushing water inlet pipe 8 is used to inject flushing water into the sealing chamber 2. The flushing water cleans and cools the mechanical seal structure 7, and then carries solid particles and discharges from the liquid discharge part of the sealing chamber 2.

[0042] Regarding the shaft hole 4, it mainly serves as a passage for the rotating shaft 3 to pass through the sealing cavity 2 and also as a drainage part for the flushing water in the sealing cavity 2. Therefore, the diameter of the shaft hole 4 is slightly larger than that of the rotating shaft 3, so that there is an annular gap between the inner wall of the shaft hole 4 and the rotating shaft 3, and the flushing water can be discharged from this gap.

[0043] Correspondingly, the diameter of the shaft hole 4 is also smaller than that of the sealing cavity 2, so that a step is formed between the sealing cavity 2 and the shaft hole 4. In the prior art, due to the existence of this step, a local reflux dead zone is formed in the part of the sealing cavity 2 below the step. It is difficult for the solid particles in this area to cross the step and be discharged from the annular gap between the rotating shaft 3 and the inner wall of the shaft hole 4, resulting in a large amount of solid particles being retained in the sealing cavity 2. The retained solid particles are likely to cause damage to the mechanical seal and affect the service life of the mechanical seal.

[0044] In view of this, in this embodiment, an axial pushing structure 5 is arranged in the sealing cavity 2 to apply an axial driving force to the medium and solid particles in the sealing cavity 2, so that the solid particles can be away from the mechanical seal structure 7, improving the working environment of the mechanical seal, reducing the abrasion and damage speed of the mechanical seal, extending the service life of the mechanical seal, and accelerating the medium flow rate, making it exceed the sedimentation flow rate of the solid particles, avoiding the sedimentation phenomenon, enabling the solid particles to be discharged from the shaft hole 4 with the flowing medium and not settling and staying in the sealing cavity 2, realizing the reduction and elimination of solid particles in the sealing cavity 2.

[0045] Specifically, referring to Figure 1 , in this embodiment, the axial pushing structure 5 is arranged on the rotating shaft 3, so that the axial pushing structure 5 can rotate with the rotating shaft 3. When the axial pushing structure 5 rotates with the rotating shaft 3, it can apply an axial driving force from the mechanical seal structure 7 to the shaft hole 4 direction to the medium in the sealing cavity 2, so that the solid particles in the sealing cavity 2 are away from the mechanical seal structure 7, thereby realizing the reduction of solid particles near the mechanical seal structure 7 and improving the working environment of the mechanical seal. By setting it in this way, the operation of the structure component (rotating shaft 3) of the pump itself can be used to provide driving force for the axial pushing structure 5, making clever use of the internal energy of the pump, without adding a power source, saving costs, and its structure is simpler and the installation is more convenient.

[0046] More specifically, in this embodiment, the axial pushing structure 5 can be an axial flow impeller, a spiral blade, etc. Taking the spiral blade as an example, when the blade rotates with the rotating shaft 3, the spiral blade can apply an axial driving force from right to left to the medium in the sealing cavity 2, so that the solid particles move with the medium in the direction away from the mechanical seal structure 7 and close to the shaft hole 4, achieving the purpose of reducing the solid particles wandering near the mechanical seal structure 7.

[0047] Furthermore, referring to Figure 1, in this embodiment, the rotational diameter of the axial pushing structure 5 rotating with the rotating shaft 3 is more than three - quarters of the diameter of the sealing cavity 2. Herein, the rotational diameter can be understood as the diameter of the circular locus where the outermost part of the axial pushing structure 5 is located when it rotates. With such a setting, the rotational diameter of the axial pushing structure 5 rotating with the rotating shaft 3 is slightly smaller than the diameter of the sealing cavity 2. When the axial pushing structure 5 rotates, its rotating surface can almost cover the entire longitudinal section of the sealing cavity 2, increasing the action range of the axial pushing structure 5, enhancing the pushing effect of the axial pushing structure 5 on solid particles, ensuring that most of the solid particles in the sealing cavity 2 can move away from the mechanical seal structure 7, guaranteeing an operating environment with no or few solid particles near the mechanical seal structure 7, reducing the influence of solid particles in the sealing cavity 2 on the mechanical seal structure 7, prolonging the service life of the mechanical seal structure 7, and improving the reliability of the pump.

[0048] Further, referring to Figure 1 , in this embodiment, a flow - guiding surface 6 is arranged in the sealing cavity 2. The flow - guiding surface 6 extends at least from the inner wall of the sealing cavity 2 below the shaft hole 4 to the shaft hole 4, and the included angle between the flow - guiding surface 6 and the inner wall of the sealing cavity 2 is an obtuse angle. With such a setting, since the included angle between the flow - guiding surface 6 and the inner wall of the sealing cavity 2 is an obtuse angle, the flow - guiding surface 6 is an inclined plane inclined relative to the inner wall of the sealing cavity 2. This inclined plane is equivalent to a gentle slope connecting the inner wall of the sealing cavity 2 and the shaft hole 4, which can play a role in transitional flow - guiding, eliminating the flow dead zone at the vertical step between the shaft hole 4 and the sealing cavity 2, enabling solid particles even below the shaft hole 4 to move along the flow - guiding surface 6 to the gap of the shaft hole 4 and finally be discharged outwards, avoiding the precipitation of solid particles at the bottom of the sealing cavity 2, and having a better solid - particle reduction effect.

[0049] Even further, referring to Figure 1 , in this embodiment, the flow - guiding surface 6 is circumferentially connected between the inner wall of the shaft hole 4 and the inner wall of the sealing cavity 2. With such a setting, the flow - guiding surface 6 can cover the entire circumferential range of the step, enabling the flow - guiding surface 6 not only to guide the flow of solid particles at the bottom of the sealing cavity 2 but also to guide the flow of solid particles at other positions in the sealing cavity 2, improving the outer - discharge efficiency of solid particles and enhancing the solid - particle reduction effect. Specifically, the flow - guiding surface 6 is a conical surface connecting the inner wall of the sealing cavity 2 and the shaft hole 4.

[0050] Even further, in this embodiment, the included angle between the flow - guiding surface 6 and the inner wall of the sealing cavity 2 is greater than or equal to 120 degrees. For example, it can be 120 degrees, 130 degrees, 160 degrees, etc. With such a setting, the slope of the flow - guiding surface 6 can be reduced, the difficulty of solid particles flowing along the flow - guiding surface 6 can be lowered, and thus the outer - discharge effect of solid particles can be improved.

[0051] Correspondingly, referring to Figure 1, in this embodiment, the axial pushing structure 5 is arranged between the mechanical seal structure 7 and the intersection of the flow guiding surface 6 and the inner wall of the sealing cavity 2, that is to say, the part of the axial pushing structure 5 located outside the flow guiding surface 6. With such an arrangement, the axial pushing structure 5 can push the solid particles at the bottom of the sealing cavity 2 onto the flow guiding surface 6 and make the solid particles discharge outward along the flow guiding surface 6, enhancing the reduction effect of the solid particles in the sealing cavity 2.

[0052] Furthermore, referring to Figure 1 , in this embodiment, the axial pushing structure 5 is located on the side of the sealing cavity 2 close to the mechanical seal structure 7, that is to say, the axial pushing structure 5 is arranged close to the mechanical seal structure 7. In this way, the acting range of the axial pushing structure 5 can be further increased, and the reduction effect of the solid particles can be improved.

[0053] Based on the solid particle reduction structure provided by the present utility model, its working principle is as follows:

[0054] Flush water is poured into the sealing cavity 2 through the flushing water inlet pipe 8. The flushing water cleans and cools the mechanical seal structure 7, and then flows towards the shaft hole 4 while carrying the flushed solid particles. At the same time, the rotating shaft 3 drives the axial pushing structure 5 to rotate, and the axial pushing structure 5 applies an axial driving force to the flushing water to increase the flow rate of the flushing water. On the one hand, it makes the solid particles in the flushing water away from the mechanical seal structure 7, creating a working environment without or with few solid particles for the mechanical seal structure 7. On the other hand, it makes the axial flow velocity of the solid particles greater than the sedimentation velocity, so that the solid particles are discharged from the gap of the shaft hole 4 before settling at the bottom of the sealing cavity 2, realizing the external discharge of the solid particles. Moreover, even if some solid particles settle at the bottom of the sealing cavity 2, they can also be discharged through the guiding action of the flow guiding surface 6, making the reduction effect of the solid particles better.

[0055] The technical features of the above embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as the combinations of these technical features do not conflict, they should be considered as the scope described in this specification.

[0056] The above embodiments only represent several implementation manners of the present application, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the utility model patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present application, several deformations and improvements can still be made, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims.

Claims

1. A solid particle reduction structure for a sealed cavity, characterized in that: include: A casing (1), wherein the sealed cavity (2) is arranged in the casing (1), a mechanical sealing structure (7) is arranged at a first end of the casing (1) located at the sealed cavity (2), and an axial hole (4) communicating with the sealed cavity (2) is arranged at a second end of the casing (1); A rotating shaft (3), the rotating shaft (3) is arranged in the sealing cavity (2) along the axial direction and passes through the shaft hole (4), and a gap is provided between the rotating shaft (3) and the inner wall of the shaft hole (4); An axial propulsion structure (5) is arranged on the rotating shaft (3) and is located in the sealing chamber (2), and is used to apply an axial propulsion force from the mechanical sealing structure (7) to the shaft hole (4) to the medium in the sealing chamber (2) when the rotating shaft (3) rotates.

2. The solid particle reduction structure according to claim 1, characterized in that: A flow guide surface (6) is provided in the sealing cavity (2), and the flow guide surface (6) at least extends from the inner wall of the sealing cavity (2) below the axial hole (4) to the axial hole (4), and the angle between the flow guide surface (6) and the inner wall of the sealing cavity (2) is an obtuse angle.

3. The solid particle reduction structure according to claim 2, characterized in that: The guide surface (6) is circumferentially connected between the inner wall of the shaft hole (4) and the inner wall of the sealing cavity (2).

4. The solid particle reduction structure according to claim 2, characterized in that: The flow guide surface (6) is a conical surface.

5. The solid particle reduction structure according to claim 2, characterized in that: The included angle between the flow guide surface (6) and the inner wall of the sealing cavity (2) is greater than or equal to 120 degrees.

6. The solid particle reduction structure according to claim 2, 3, 4 or 5, characterized in that: The axial pushing structure (5) is arranged between the boundary between the mechanical sealing structure (7), the flow guide surface (6) and the inner wall of the sealing cavity (2).

7. The solid particle reduction structure according to claim 6, characterized in that: The axial pushing structure (5) is located in the sealing cavity (2) on a side close to the mechanical sealing structure (7).

8. The solid particle reduction structure according to claim 1, characterized in that: The rotation diameter of the axial pushing structure (5) rotating with the rotating shaft (3) is more than three quarters of the diameter of the sealing cavity (2).

9. The solid particle reduction structure according to claim 1, characterized in that: The axial propulsion structure (5) comprises an axial flow impeller or a spiral blade.

10. The solid particle reduction structure according to claim 1, characterized in that: A flushing water inlet pipe (8) is provided on the mechanical sealing structure (7), and the flushing water inlet pipe (8) is connected to the sealing cavity (2).

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