Split mechanical seal structure

Abstract

The utility model relates to mechanical seal technical field, concretely is a kind of split mechanical seal structure.The utility model, including static ring subassembly, dynamic ring subassembly, drive seat, spring and the connecting flange for fixed installation, static ring subassembly and dynamic ring subassembly are both two half formula structure that can be along axial split, static ring subassembly includes static ring seat, static ring piece A, static ring piece B and static ring pressboard, the static ring seat is fixedly connected with the connecting flange by screw C, the connecting flange is fixed on equipment rack by screw A and screw B, static ring piece A and static ring piece B are split to form static ring and are fixed in static ring seat by static ring pressboard and screw E pressure tightly, static ring seat with static ring piece A, static ring piece B between being equipped with sealing ring D and sealing ring E, dynamic ring subassembly includes dynamic ring seat and dynamic ring pressboard, the dynamic ring seat is sleeved on rotating shaft.Solve the problem that existing conventional integral mechanical seal is not easy to disassemble, process is tedious and time-consuming.

Description

Technical Field

[0001] This utility model relates to the field of mechanical seal technology, and in particular to a split mechanical seal structure. Background Technology

[0002] Mechanical seals, also known as face seals, are high-performance sealing devices used in rotating equipment (such as pumps, compressors, agitators, reactors, etc.) to establish a dynamic seal between a rotating shaft and a stationary housing, preventing the working medium (liquid or gas) from leaking along the shaft while preventing external impurities from entering the equipment.

[0003] The most significant drawback of existing traditional integral mechanical seals lies in their non-separable integral structure. This means that the rotor (or long shaft system) must be moved axially during installation or replacement, which is not only cumbersome and time-consuming with high maintenance costs, but also difficult to implement or even impossible to operate in situations where space is limited or the rotor cannot be moved. Utility Model Content

[0004] The purpose of this invention is to address the shortcomings of existing traditional integral mechanical seals, which are difficult to disassemble and assemble, and involve a cumbersome and time-consuming process. Therefore, this invention proposes a split mechanical seal structure.

[0005] To achieve the above objectives, this utility model adopts the following technical solution: a split mechanical seal structure, including a stationary ring assembly, a rotating ring assembly, a drive seat, a spring, and a connecting flange for fixed installation, wherein both the stationary ring assembly and the rotating ring assembly are axially split into two halves.

[0006] The stationary ring assembly includes a stationary ring seat, stationary ring component A, stationary ring component B, and a stationary ring pressure plate. The stationary ring seat is fixedly connected to the connecting flange by screws C. The connecting flange is fixed to the equipment frame by screws A and B. The stationary ring component A and stationary ring component B are assembled to form a stationary ring and are pressed and fixed in the stationary ring seat by the stationary ring pressure plate and screws E. A sealing ring D and a sealing ring E are provided between the stationary ring seat and stationary ring components A and B.

[0007] The rotating ring assembly includes a rotating ring seat and a rotating ring pressure plate. The rotating ring seat is sleeved on the rotating shaft, and its split surface is fastened to the rotating shaft by a screw and a nut. The nut is prevented from loosening by a limit card. The drive seat is fixed to the rotating shaft by a fastening screw and has a transmission cooperation with the rotating ring seat. The spring is disposed between the drive seat and the rotating ring seat.

[0008] The stationary ring assembly and the rotating ring assembly are aligned by at least two sets of locating pin assemblies; the first set of locating pin assemblies includes a locating pin A disposed on the stationary ring seat and a corresponding pin hole disposed on the connecting flange; the second set of locating pin assemblies includes a locating pin B disposed on the rotating ring seat and a corresponding pin hole disposed on the drive seat.

[0009] Preferably, the rotating ring seat has a semi-circular groove for accommodating the spring on its split surface, and the two halves of the rotating ring seat form a complete spring accommodating chamber when they are closed.

[0010] Preferably, the split surfaces of the stationary ring A and stationary ring B are provided with mutually cooperating stepped structures.

[0011] Preferably, a sealing ring A and a sealing ring B are provided between the moving ring seat and the rotating shaft.

[0012] Preferably, a sealing ring C is provided between the stationary ring seat and the connecting flange.

[0013] Preferably, the drive seat and the moving ring seat transmit torque through a meshing structure of protrusions and grooves, and are further connected by screws D.

[0014] Preferably, a locating pin C and a locating pin D for circumferential positioning are further provided between the stationary ring seat and the connecting flange.

[0015] Preferably, the connecting flange is further provided with a screw F for tightening the stationary ring seat.

[0016] Preferably, the spring is a plurality of helical compression springs evenly distributed along the circumference.

[0017] Preferably, an auxiliary sealing ring is provided between the drive seat and the rotating shaft.

[0018] In summary, the beneficial effects of this utility model are as follows:

[0019] In this invention, the superior alignment and stability are achieved by using multiple sets of precision positioning pins between the stationary ring assembly and the connecting flange, and between the rotating ring assembly and the drive seat. This ensures that the two halves of the assembly can be quickly and accurately restored to the designed concentricity and perpendicularity during assembly, greatly improving the fit of the sealing end faces and avoiding uneven wear and leakage caused by poor alignment.

[0020] Excellent sealing reliability: Multi-layered and multi-type sealing structures are designed for all potential leakage paths, forming a complete sealing system that effectively controls the leakage risks that may be caused by the split structure.

[0021] Efficient torque transmission: The drive seat transmits torque directly and reliably by engaging with the groove on the moving ring seat through the protrusion, avoiding slippage or jamming.

[0022] Stable end-face compensation: The spring is properly placed in a specially designed chamber inside the moving ring seat, and is evenly distributed circumferentially, providing a smooth and consistent axial thrust for the moving ring assembly, ensuring that the sealing end face has good following and fit under various working conditions.

[0023] Excellent installation and maintainability: This utility model fully retains the core advantages of split seals. All major components are split designs, allowing for installation, debugging, and replacement without moving the main equipment, significantly reducing downtime and maintenance costs. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the structure of this utility model.

[0025] Legend: 1. Screw; 2. Nut; 3. Fastening screw; 4. Limiting clip; 5. Sealing ring A; 6. Sealing ring B; 7. Moving ring seat; 8. Screw A; 9. Screw B; 10. Flange; 11. Sealing ring C; 12. Stationary ring seat; 13. Sealing ring D; 14. Sealing ring E; 15. Stationary ring A; 16. Locating pin A; 17. Screw C; 18. Locating pin B; 19. Screw D; 20. Moving ring pressure plate; 21. Stationary ring pressure plate; 22. Stationary ring B; 23. Screw E; 24. Locating pin C; 25. Locating pin D; 26. Screw F; 27. Spring; 28. Drive seat. Detailed Implementation

[0026] Reference Figure 1 As shown, this utility model provides a technical solution: the mechanical seal is fixed to the equipment housing via a two-part split connecting flange 10. The two halves of the connecting flange 10 are fastened to the equipment foundation by screws A8 and B9, forming a complete mounting platform. The stationary ring assembly is fixedly mounted on the connecting flange 10 by screws C17.

[0027] The following is a detailed description of the specific structure and function of the entire system: The stationary ring assembly is the sealed stationary part, located on the medium side. It mainly consists of the stationary ring seat 12, stationary ring component A15, stationary ring component B22, stationary ring pressure plate 21, and related fastening and sealing components.

[0028] The stationary ring seat 12 is a two-part split structure, which is fixed to the connecting flange 10 by screws C17. To ensure the accuracy of the connection, locating pins A16, C24, and D25 are provided at the mating surface. Locating pin A16 ensures axial positioning, while locating pins C24 and D25 ensure circumferential positioning, preventing the stationary ring seat 12 from rotating slightly during operation. In addition, a sealing ring groove is formed at the mating surface between the stationary ring seat 12 and the connecting flange 10, which contains a sealing ring C11 to effectively prevent media leakage from this point.

[0029] The stationary ring components A15 and B22 are two halves of a rigid material, which, when joined together, form a complete stationary ring. Their split surfaces are machined with a precise stepped structure to ensure that no circumferential or radial misalignment occurs after joining. The joined stationary ring is placed in the inner cavity of the stationary ring seat 12 and secured by another two-half stationary ring pressure plate 21 and screws E23. Sealing rings D13 and E14 are respectively provided on the contact surfaces between the stationary ring and the stationary ring seat 12 to achieve a static seal.

[0030] The rotating ring assembly is a sealed rotating part that rotates with the shaft. It mainly consists of a rotating ring seat 7, a rotating ring pressure plate 20, a spring 27, and a drive seat 28.

[0031] The rotating ring seat 7 is a two-part split structure that directly covers the rotating shaft. The two halves are tightened together by screws 1 and nuts 2, and a limiting card 4 is inserted into the groove at the end of screw 1 to prevent nut 2 from loosening. The rotating ring pressure plate 20 uses screws (not separately labeled in the figure, but can be understood as having a similar function to screw E23) to press the rotating ring (not shown in the figure, usually integrated with or carried by the rotating ring seat 7) onto the rotating ring seat 7. Sealing rings A5 and B6 are provided between the rotating ring seat 7 and the rotating shaft to achieve a dynamic seal between the shaft and the rotating ring seat.

[0032] The drive seat 28 is an independent, split ring-shaped part, tightly fixed to the rotating shaft by fastening screws 3, and its function is to transmit torque. The end face of the drive seat 28 is designed with protrusions that engage with corresponding grooves on the end face of the moving ring seat 7. When the shaft rotates, the torque is directly transmitted to the moving ring seat 7 through the drive seat 28. To further ensure transmission reliability, screws D19 are used to auxiliaryly connect the moving ring seat 7 and the drive seat 28. To ensure precise alignment between the moving ring seat 7 and the drive seat 28, a locating pin B18 is provided between them.

[0033] Multiple springs 27 are evenly distributed circumferentially. Semi-circular spring mounting grooves are machined on the split surface of the moving ring seat 7. When the two halves of the moving ring seat 7 are closed, these semi-circular grooves combine to form a complete circular cavity for accommodating and fixing the springs 27. One end of the spring 27 abuts against the drive seat 28, and the other end abuts against the moving ring seat 7, thereby providing a continuous axial force that presses against the end face of the stationary ring for the entire moving ring assembly.

[0034] Working principle: During installation, first, fix the two halves of the connecting flange 10 to the equipment using screws A8 and B9. Then, assemble the components of the stationary ring assembly (stationary ring seat 12, stationary ring component A15, stationary ring component B22, stationary ring pressure plate 21, etc.) on the shaft, fix them to the flange 10 with screws C17, and ensure alignment using locating pins.

[0035] Next, the drive seat 28 is fixed to the shaft with the fastening screws 3. Then, the spring 27 is placed into the semi-circular groove of the moving ring seat 7, covering the two halves of the moving ring seat 7 onto the shaft, so that the transmission groove on its end face engages with the protrusion on the drive seat 28. Next, the moving ring seat 7 is tightened and closed with the screw 1 and nut 2, and the upper limit clip 4 is installed to prevent loosening. Finally, screw in the screw D19 for auxiliary tightening, and install the moving ring pressure plate 20.

[0036] During operation, the rotating shaft drives the drive seat 28 to rotate, and the drive seat 28 drives the rotating ring seat 7 to rotate together via its protrusion. The thrust of the spring 27 acts on the rotating ring through the rotating ring seat 7 and the rotating ring pressure plate 20, ensuring that its end face is always tightly pressed against the stationary ring end face. This rotating rotating ring end face and the stationary ring end face form an extremely thin liquid film, constituting the main sealing surface and preventing media leakage. All other sealing rings constitute the auxiliary sealing system, preventing media leakage through other paths.

[0037] Material Selection: The friction pair materials (stationary ring A15, stationary ring B22, and rotating ring) can be pressureless sintered silicon carbide, cemented carbide, or graphite to meet the requirements of wear resistance, corrosion resistance, and high temperature resistance. Auxiliary sealing rings can be made of perfluoroether, Alflucose, or fluororubber to ensure compatibility with various chemical media. Metal components can be selected from stainless steel or special alloys such as 304, 316L, 2205, 2507, 904L, or 1.4529, depending on the corrosive environment.

[0038] The split mechanical seal of this invention is particularly suitable for working conditions with shaft diameters of 50-300mm, pressures ≤2.5MPa, temperatures ≤200℃, and linear velocities ≤5m / s, with an allowable axial movement of ±1mm.

[0039] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

Claims

1. A split mechanical seal structure, comprising a stationary ring assembly, a rotating ring assembly, a drive seat (28), a spring (27), and a connecting flange (10) for fixed installation, wherein both the stationary ring assembly and the rotating ring assembly are axially split two-half structures, characterized in that: The stationary ring assembly includes a stationary ring seat (12), a stationary ring component A (15), a stationary ring component B (22), and a stationary ring pressure plate (21). The stationary ring seat (12) is fixedly connected to the connecting flange (10) by screw C (17). The connecting flange (10) is fixed to the equipment frame by screw A (8) and screw B (9). The stationary ring component A (15) and the stationary ring component B (22) are assembled to form a stationary ring and are pressed and fixed in the stationary ring seat (12) by the stationary ring pressure plate (21) and screw E (23). A sealing ring D (13) and a sealing ring E (14) are provided between the stationary ring seat (12) and the stationary ring component A (15) and the stationary ring component B (22). The moving ring assembly includes a moving ring seat (7) and a moving ring pressure plate (20). The moving ring seat (7) is sleeved on the rotating shaft, and its split surface is fastened by a screw (1) and a nut (2). The nut (2) is prevented from loosening by a limiting card (4). The drive seat (28) is fixed on the rotating shaft by a fastening screw (3) and is in transmission cooperation with the moving ring seat (7). The spring (27) is disposed between the drive seat (28) and the moving ring seat (7). The stationary ring assembly and the rotating ring assembly are aligned by at least two sets of locating pin assemblies; the first set of locating pin assemblies includes a locating pin A (16) disposed on the stationary ring seat (12) and a corresponding pin hole disposed on the connecting flange (10); the second set of locating pin assemblies includes a locating pin B (18) disposed on the rotating ring seat (7) and a corresponding pin hole disposed on the drive seat (28).

2. The split mechanical seal structure according to claim 1, characterized in that: The rotating ring seat (7) has a semi-circular groove for accommodating the spring (27) on its split surface. When the two halves of the rotating ring seat (7) are closed, a complete spring accommodating chamber is formed.

3. The split mechanical seal structure according to claim 1, characterized in that: The static ring A (15) and static ring B (22) are provided with mutually cooperating stepped structures at their split surfaces.

4. The split mechanical seal structure according to claim 1, characterized in that: The moving ring seat (7) is provided with a sealing ring A (5) and a sealing ring B (6) between it and the rotating shaft.

5. A split mechanical seal structure according to claim 1, characterized in that: A sealing ring C (11) is provided between the stationary ring seat (12) and the connecting flange (10).

6. The split mechanical seal structure according to claim 1, characterized in that: The drive seat (28) and the moving ring seat (7) transmit torque through a meshing structure of protrusions and grooves, and are further connected by screws D (19).

7. The split mechanical seal structure according to claim 1, characterized in that: The stationary ring seat (12) and the connecting flange (10) are further provided with a locating pin C (24) and a locating pin D (25) for circumferential positioning.

8. A split mechanical seal structure according to claim 1, characterized in that: The connecting flange (10) is also provided with screws F (26) for tightening the stationary ring seat (12).

9. A split mechanical seal structure according to claim 1, characterized in that: The spring (27) is a plurality of helical compression springs evenly distributed along the circumference.

10. A split mechanical seal structure according to claim 1, characterized in that: An auxiliary sealing ring is provided between the drive seat (28) and the rotating shaft.

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