Ball valve sealing structure with self-cleaning function

Abstract

The utility model discloses a ball valve sealing structure with self -cleaning function, including ball and valve seat subassembly, the ball sealing surface outside is equipped with spiral flow guide groove, and the inside of valve seat subassembly is installed with the scraping ring of interference, and the back of valve seat subassembly is provided with wedge self -adjusting mechanism, spiral flow guide groove can produce vortex and remove small particle when medium flows, and the scraping ring removes bigger particle through mechanical scraping mode, and wedge self -adjusting mechanism includes wedge adjusting block and spring, and can automatically compensate gap after the wear of sealing surface. The structure passes through multiple protection mechanism, and effectively solved the sealing surface wear, particle pressure inlay and sealing failure problem of ball valve under the particle medium working condition, significantly improved the service life and reliability of valve, is applicable to the harsh working condition of high solid content.

Description

Technical Field

[0001] This utility model belongs to the field of ball valve technology, and in particular relates to a ball valve sealing structure with self-cleaning function. Background Technology

[0002] Ball valves, as key control components in industrial pipelines, are widely used in slurry conveying systems in mining, metallurgy, and chemical industries. However, when the medium contains solid particles, the sealing performance of conventional ball valves faces serious challenges.

[0003] During valve opening and closing, solid particles can easily intrude into the sealing area between the valve ball and the valve seat, causing scratches and wear on the sealing surface, or even becoming embedded in the sealing surface, damaging the integrity of the sealing line and leading to media leakage. To address this problem, two main improvement directions have emerged in the existing technology: one is to install a scraper structure at the valve seat to remove particles through mechanical scraping; the other is to use an elastic element to push the valve seat and compensate for the wear of the sealing surface.

[0004] However, these solutions have significant shortcomings. The scraper structure can only remove larger particles, ineffective against fine particles, and it itself wears down, with its cleaning effect decreasing over time. The elastic compensation structure is prone to jamming in particulate media, losing its compensation function, and cannot solve the problem of accelerated wear caused by continuous particle accumulation. More importantly, existing technologies mostly focus on achieving a single function, lacking synergistic consideration of "self-cleaning" and "wear compensation," making it difficult to meet the long-term sealing requirements under high solids content conditions.

[0005] Therefore, there is an urgent need in the field for a ball valve sealing structure that can simultaneously achieve effective self-cleaning and reliable wear compensation in order to improve the service life and reliability of valves in slurry media. Utility Model Content

[0006] To address the problems existing in the prior art, this utility model provides a ball valve sealing structure with self-cleaning function.

[0007] This invention is implemented as follows: A ball valve sealing structure with self-cleaning function includes a ball and a valve seat assembly that seals with the ball. The key features are: a spiral guide groove is provided on the outer side of the sealing surface of the ball; a scraping ring is interference-fitted onto the inner side of the valve seat assembly; a wedge-shaped self-adjusting mechanism is provided on the back of the valve seat assembly; the wedge-shaped self-adjusting mechanism includes a wedge-shaped adjusting block and a spring, the spring applying a preload to the wedge-shaped adjusting block, and the inclined surface of the wedge-shaped adjusting block engaging with the corresponding inclined surface on the back of the valve seat body; when the medium flows through the spiral guide groove, a vortex is formed to clean the sealing surface, and the scraping ring is used to scrape off particles from the surface of the ball; when the sealing surface wears, the preload of the spring pushes the wedge-shaped adjusting block to move axially, and the inclined surface engagement converts the axial movement into radial compression of the valve seat body, thereby pushing the entire valve seat assembly towards the ball to automatically compensate for the wear gap.

[0008] More preferably, the cross-sectional shape of the spiral guide channel is an equilateral triangle with rounded corners at the apex, and one side of the equilateral triangle is parallel to the direction of medium flow.

[0009] Preferably, the scraping ring is made of PTFE material and is installed in the annular groove inside the valve seat body by an interference fit.

[0010] More preferably, the sealing surface of the sphere is provided with a wear-resistant coating, which is a tungsten carbide coating formed by laser cladding.

[0011] In a further preferred embodiment, the valve seat assembly also includes a valve seat adjusting ring and a pressure ring, with the valve seat body, valve seat adjusting ring and pressure ring connected in sequence, and the wedge-shaped self-adjusting mechanism disposed within the cavity formed by the valve seat body and the valve seat adjusting ring.

[0012] The advantages and technical effects of this utility model are as follows: In summary, this utility model constructs a complete self-cleaning and automatic compensation system through three technical means: fluid cleaning via a spiral guide groove, mechanical scraping via a scraping ring, and wear compensation via a wedge-shaped self-adjusting mechanism. This structure can effectively cope with the sealing challenges under conditions containing solid particles, prevent particle embedding and wear on the sealing surface, and automatically restore the sealing pressure after wear occurs, significantly extending the valve maintenance cycle and service life. The entire design is compact and reasonable, with all components working in concert, providing technical assurance for the reliable operation of the ball valve under harsh conditions. Attached Figure Description

[0013] Figure 1 This is a schematic axial cross-sectional view of the overall structure of this design; Figure 2 This is a schematic diagram of a spiral guide channel; In the diagram: 1. Ball; 2. Valve body; 3. Spiral guide groove; 4. Scraper ring; 5. Valve seat body; 6. Spring; 7. Wedge-shaped adjusting block; 8. Valve seat adjusting ring; 9. Pressure ring. Detailed Implementation

[0014] To make the objectives, technical solutions, and advantages of this utility model clearer, the following detailed description is provided in conjunction with embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this utility model.

[0015] Please see Figures 1 to 2 A ball valve sealing structure with self-cleaning function includes a ball 1 and a valve seat assembly that seals with the ball 1. The outer side of the sealing surface of the ball 1 is provided with a spiral guide groove 3. A scraping ring 4 is interference-fitted on the inner side of the valve seat assembly. A wedge-shaped self-adjusting mechanism is provided on the back of the valve seat assembly. The wedge-shaped self-adjusting mechanism includes a wedge-shaped adjusting block 7 and a spring 6. The spring 6 applies a preload to the wedge-shaped adjusting block 7, and the inclined surface of the wedge-shaped adjusting block 7 cooperates with the corresponding inclined surface on the back of the valve seat body 5.

[0016] This technical solution achieves long-term sealing of the ball valve in particulate media conditions through a triple protection mechanism. The spiral guide groove generates a vortex effect during media flow, effectively removing fine particles from the sealing surface; the scraper ring removes larger particles through mechanical scraping; and the wedge-shaped self-adjusting mechanism automatically compensates for gaps after the sealing surface wears. This multi-protection design significantly improves the service life of the ball valve in media containing solid particles, reduces maintenance frequency, and ensures sealing reliability.

[0017] More preferably, the cross-sectional shape of the spiral guide channel 3 is an equilateral triangle with rounded corners at the apex, and one side of the equilateral triangle is parallel to the direction of medium flow.

[0018] This specially designed trough structure optimizes hydrodynamic performance, generating strong vortices while reducing flow resistance losses. The rounded corners prevent stress concentration and improve structural strength; the specific angle between the equilateral triangular cross-section and the flow direction ensures optimal vortex generation efficiency, enhancing cleaning performance without compromising the overall strength of the sphere.

[0019] Preferably, the scraper ring 4 is made of PTFE material and is installed in the annular groove inside the valve seat body 5 by an interference fit. PTFE material has excellent self-lubricating properties and chemical stability, which can effectively scrape off particles without damaging the surface of the ball. The interference fit installation ensures the scraper ring is firmly positioned, preventing displacement or detachment under the scouring of the medium. At the same time, the thermal expansion and contraction properties of PTFE are used to achieve a tight assembly, ensuring long-term reliability.

[0020] Preferably, spring 6 is a high-rigidity return helical spring. A high-rigidity helical spring provides a stable and sustained preload, ensuring the wedge mechanism has sufficient compensation force and rapid response capability. Its excellent return performance ensures that the compensation mechanism can be activated immediately after wear occurs, maintaining a constant sealing pressure and avoiding compensation failure due to spring fatigue.

[0021] Preferably, the sealing surface of the sphere 1 is provided with a wear-resistant coating, which is a tungsten carbide coating formed by laser cladding. The tungsten carbide coating has extremely high hardness and wear resistance, significantly improving the sealing surface's resistance to particle erosion. Laser cladding technology ensures a metallurgical bond between the coating and the substrate, resulting in high bonding strength and resistance to peeling, greatly extending the sphere's service life, making it particularly suitable for harsh working conditions with high solids content.

[0022] In a further preferred embodiment, the valve seat assembly also includes a valve seat adjusting ring 8 and a pressure ring 9. The valve seat body 5, valve seat adjusting ring 8, and pressure ring 9 are connected sequentially, and the wedge-shaped self-adjusting mechanism is disposed within the cavity formed by the valve seat body 5 and the valve seat adjusting ring 8. This modular design makes assembly more convenient, and the division of labor among the components is clear. The valve seat adjusting ring and the pressure ring together form a stable support structure, ensuring the precise movement of the wedge-shaped mechanism; the cavity design provides a protected working space for the self-adjusting mechanism, preventing media intrusion from affecting the mechanism's operation and improving the reliability of the entire compensation system.

[0023] The working principle of this invention is as follows: When the valve is opened and the medium flows, the fluid passes through the spiral guide groove 3 on the outer side of the sealing surface of the ball 1. Due to the special spiral design and specific cross-sectional shape of the groove, the medium generates a strong spiral vortex as it flows through. This vortex continuously scours the sealing contact area between the ball and the valve seat, agitating the fine particles attached to the sealing surface and carrying them away with the main fluid, achieving the first stage of cleaning. Simultaneously, during the rotation of the ball 1, the PTFE scraping ring 4, interference-fitted to the inner side of the valve seat 5, mechanically scrapes the surface of the ball, effectively removing larger particles not removed by the vortex, completing the second stage of cleaning. When long-term use of the valve causes wear and gaps to appear on the sealing surface, the wedge-shaped self-adjusting mechanism starts working: the preload of the spring 6 pushes the wedge-shaped adjusting block 7 to move axially along its inclined surface. Through the inclined surface engagement, the axial displacement is converted into radial compression of the valve seat 5, thereby pushing the entire valve seat assembly towards the ball 1, automatically compensating for the gaps caused by wear and restoring the required sealing pressure. This working mechanism ensures that the valve maintains reliable sealing performance throughout its entire service life.

[0024] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A ball valve sealing structure with self-cleaning function, comprising a ball (1) and a valve seat assembly that seals with the ball (1), characterized in that: The outer side of the sealing surface of the sphere (1) is provided with a spiral guide groove (3); The valve seat assembly is interference-fitted with a scraping ring (4) on its inner side. A wedge-shaped self-adjusting mechanism is provided on the back of the valve seat assembly; The wedge self-adjusting mechanism includes a wedge adjusting block (7) and a spring (6). The spring (6) applies a preload to the wedge adjusting block (7). The inclined surface of the wedge adjusting block (7) is engaged with the corresponding inclined surface on the back of the valve seat body (5). When the medium flows through the spiral guide groove (3), a vortex is formed to clean the sealing surface. The scraping ring (4) is used to scrape off particles on the surface of the ball (1). When the sealing surface is worn, the preload of the spring (6) pushes the wedge-shaped adjusting block (7) to move axially. The axial movement is converted into radial compression on the valve seat body (5) through the inclined surface cooperation, thereby pushing the entire valve seat assembly to move towards the ball (1) to automatically compensate for the wear gap.

2. The ball valve sealing structure with self-cleaning function according to claim 1, characterized in that: The cross-sectional shape of the spiral guide groove (3) is an equilateral triangle with rounded corners at the apex, and one side of the equilateral triangle is parallel to the direction of medium flow.

3. The ball valve sealing structure with self-cleaning function according to claim 1, characterized in that: The scraping ring (4) is made of PTFE material and is installed in the annular groove inside the valve seat body (5) by interference fit.

4. The ball valve sealing structure with self-cleaning function according to claim 1, characterized in that: The sealing surface of the sphere (1) is provided with a wear-resistant coating, which is a tungsten carbide coating formed by laser cladding.

5. The ball valve sealing structure with self-cleaning function according to claim 1, characterized in that: The valve seat assembly also includes a valve seat adjusting ring (8) and a pressure ring (9). The valve seat body (5), valve seat adjusting ring (8) and pressure ring (9) are connected in sequence. The wedge-shaped self-adjusting mechanism is disposed in the cavity formed by the valve seat body (5) and the valve seat adjusting ring (8).

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