A high-temperature resistant rotary shaft seal

Abstract

This utility model discloses a high-temperature resistant rotary shaft seal, belonging to the field of shaft seals. It includes a rotary shaft with an expansion joint mounted on it. The expansion joint has connecting flanges at both ends. A secondary sealing assembly is provided on the end face of one set of connecting flanges, and the other end face of the other set of connecting flanges is also connected to the secondary sealing assembly. A dustproof assembly is provided on the connecting flanges, comprising two sets of dustproof parts and two sets of opposing fixed parts between the two sets of dustproof parts. This high-temperature resistant rotary shaft seal utilizes a primary packing seal, which is compressed by a packing gland. A cooling jacket circulates water for cooling, and a wear-resistant copper sleeve reduces friction. The secondary gas seal relies on compressed air to control the sealing ring to hold the shaft. The expansion joint compensates for the shaft's thermal expansion, nitrogen is introduced through the nitrogen purging port to create positive pressure and prevent leakage, O-rings seal the connection gaps, and a positioning screw stabilizes the flange position.

Description

Technical Field

[0001] This utility model relates to the field of shaft sealing technology, and in particular to a high-temperature resistant rotary shaft seal. Background Technology

[0002] As a core component of horizontal high-temperature reactors, shaft seals must possess strong environmental adaptability to meet the demands of complex operating conditions. They must not only achieve efficient sealing under positive pressure to prevent material leakage but also adapt to negative pressure operation to prevent external air infiltration. In particular, they must withstand the continuous high temperatures during the reaction process. Their sealing reliability directly determines the operational safety and production stability of the reactor. However, air leakage caused by shaft seal failure has become a major safety hazard in the use of horizontal high-temperature reactors.

[0003] Traditional packing seals are commonly used for the rotary shaft seals of horizontal high-temperature reactors. While these seals are low-cost and easy to install, their sealing performance is prone to continuous decline due to high-temperature aging and packing wear during long-term operation, making it difficult to maintain a stable sealing effect. This is especially true under high-temperature and pressure fluctuation conditions, which increases the risk of leakage. In some scenarios where high sealing performance is required, double-end mechanical seals are used. Although their sealing effect is superior to packing seals, they have limitations in adaptability to different operating conditions. They struggle to cope with the excessive elongation of the rotating shaft under high-temperature environments. Thermal elongation of the shaft can easily cause misalignment and damage to the dynamic and static sealing rings, directly affecting sealing performance. Furthermore, replacing double-end mechanical seals is cumbersome, often requiring significant disassembly of the reactor, which not only consumes a lot of production time but also leads to prolonged production line downtime, reducing overall production efficiency. Therefore, a multi-functional shaft sealing device needs to be designed.

[0004] It should be noted that the information disclosed in this background section is only for understanding the background technology of this application concept, and therefore may include information that does not constitute prior art. Utility Model Content

[0005] This utility model provides a high-temperature resistant rotary shaft seal to solve the problems of traditional packing seals being easily damaged at high temperatures and having a high risk of leakage; and double-end mechanical seals being difficult to adapt to shaft thermal expansion, requiring frequent replacement, and affecting production efficiency.

[0006] This utility model embodiment adopts the following technical solution: a high-temperature resistant rotary shaft seal. It mainly includes a rotary shaft, on which an expansion joint is fitted. The expansion joint has connecting flanges at both ends. One set of connecting flanges has a secondary sealing assembly on its end face to provide a first-level seal for the rotary shaft. The other set of connecting flanges has a secondary sealing assembly on its other end face to provide a second-level seal for the rotary shaft. A dustproof assembly is provided on the connecting flange to prevent external dust from entering the connection gap between the secondary sealing assembly and the connecting flange. The dustproof assembly includes two sets of dustproof parts on the connecting flange, and two sets of opposing fixing parts are provided between the two sets of dustproof parts.

[0007] Furthermore, the secondary sealing assembly includes an air-tight device fixed to one end face of the connecting flange. The air-tight device consists of a base fixed to one end face of the connecting flange, a first rotating ring, a clamp, a second rotating ring, and a pressure cover. A sealing ring is provided between the clamp and the rotating shaft.

[0008] Furthermore, the expansion joint has multiple sets of positioning screws connected between its two ends of the connecting flange. The two ends of the positioning screw pass through the connecting flange and are threadedly connected to nuts. A gasket is provided between the nuts and the connecting flange. The expansion joint has a nitrogen purging port for introducing inert gas.

[0009] Furthermore, the secondary sealing assembly includes a stuffing box connected to the other end face of the connecting flange, the stuffing box being sleeved on the rotating shaft, the stuffing box having connecting flanges at both ends, one end of the positioning screw passing through the connecting flange and threadedly connected to a nut, and an O-ring being provided between the stuffing box and the expansion joint, with a portion of the O-ring being embedded in the end face of the connecting flange.

[0010] Furthermore, a cooling jacket is provided around the outer periphery of the stuffing box. The cooling jacket has a cooling water inlet and a cooling water outlet. The cooling water inlet is used to introduce cooling water, and the cooling water circulates within the cooling jacket before flowing out from the cooling water outlet, thereby achieving heat exchange cooling.

[0011] Furthermore, a sealing copper sleeve is simultaneously fitted inside the stuffing box on the rotating shaft, and a packing gland is fixed on the cooling jacket. There is a packing gap between the packing gland and the stuffing box, and a packing seal is provided in the packing gap.

[0012] Furthermore, the dustproof part includes two sets of symmetrically arranged mounting arc blocks fixed to the connecting flange. A hinge is vertically arranged on the mounting arc block. The hinge has a movable rotating part. A dust cover is fixed on the hinge. The dust cover has a hollow columnar structure split in half. The two sets of dust covers are joined together to form a columnar structure to cover the airtight device. A silicone sealing strip is provided on the side of the two sets of dust covers that are in contact with each other.

[0013] Furthermore, the dust cover located at the upper end is defined as dust cover one, and the dust cover located at the lower end is defined as dust cover two. The fixing part includes a mounting base fixed to the surface of dust cover two. The mounting base has an integrally extended upward protrusion. The protrusion is movably connected to a gripping member through a shaft. A connecting shaft is movably provided through the front end of the gripping member. A U-shaped hook is connected to the connecting shaft. A fastener adapted to the hook is fixed to the surface of dust cover one.

[0014] The above-mentioned technical solutions adopted in the embodiments of this utility model can achieve the following beneficial effects:

[0015] A high-temperature resistant rotary shaft seal employs a primary packing seal (composed of multiple layers of packing within a stuffing box) that achieves basic sealing through packing gland compression. A cooling jacket circulates cooling water to reduce the aging rate of the packing due to high temperatures, while a wear-resistant copper sleeve minimizes direct wear between the shaft and the packing. A secondary gas-tight seal controls the tightness between the sealing ring and the shaft by introducing compressed air, creating a double-seal guarantee. An expansion joint in the middle compensates for the thermal expansion of the shaft at high temperatures, preventing shaft deformation that could lead to misalignment and damage to the sealing components. Its nitrogen purging port introduces nitrogen to create internal positive pressure; even if a minor leak occurs in the primary packing, the positive pressure nitrogen prevents external air from entering the reactor, thus preventing material oxidation or combustion. O-rings further seal the connection between the expansion joint and the stuffing box, and positioning screws ensure the stability of the flange positions at both ends of the expansion joint. Attached Figure Description

[0016] The accompanying drawings, which are provided to further illustrate the present invention and constitute a part of the present invention, illustrate exemplary embodiments of the present invention and are used to explain the present invention, but do not constitute an undue limitation of the present invention.

[0017] In the attached diagram:

[0018] Figure 1 This is a cross-sectional view of a high-temperature resistant rotary shaft seal according to this application;

[0019] Figure 2 for Figure 1 The right view;

[0020] Figure 3 for Figure 1Schematic diagram of the expansion joint structure;

[0021] Figure 4 for Figure 1 Schematic diagram of the filling gland structure;

[0022] Figure 5 This is a schematic diagram of the three-dimensional structure of the shaft seal;

[0023] Figure 6 for Figure 5 Enlarged view of point A;

[0024] Figure label:

[0025] 1. Rotating shaft; 2. Connecting flange two; 3. Sealing copper sleeve; 4. Cooling water inlet; 5. Packing seal; 6. Packing gland; 7. Expansion joint; 71. Connecting flange one; 8. Gas sealing device; 81. Base; 82. Rotating ring one; 83. Clamp; 84. Rotating ring two; 85. Pressure cover; 9. Positioning screw; 10. Nitrogen purging port; 11. O-ring seal; 12. Stuffing box; 13. Cooling jacket; 14. Mounting arc block; 15. Hinge; 16. Rotating component; 17. Dust cover; 18. Mounting seat; 19. Protrusion; 110. Holding component; 111. Connecting shaft; 112. Hanging component; 113. Fastener. Detailed Implementation

[0026] To further illustrate the technical means and effects adopted by this utility model in order to achieve the intended utility model purpose, the following detailed description of the specific implementation methods, structure, features and effects of this utility model is provided in conjunction with the accompanying drawings and preferred embodiments.

[0027] The technical solutions provided by the various embodiments of this utility model are described in detail below with reference to the accompanying drawings.

[0028] Reference Figures 1 to 4 As shown, this utility model embodiment provides a high-temperature resistant rotary shaft seal, including a rotary shaft 1, which is used to transmit power and realize the rotation function, and an expansion joint 7 is fitted on the rotary shaft 1. The expansion joint 7 can compensate for the thermal expansion and contraction of the rotary shaft 1 caused by factors such as temperature changes, and avoid the deformation of the shaft from damaging the sealing structure. The expansion joint 7 has connecting flanges 71 at both ends, which are mainly used to connect and fix with other components.

[0029] A secondary sealing assembly is provided on the end face of a set of connecting flanges 71. This secondary sealing assembly includes an airtight device 8 fixed to the end face of the connecting flanges 71 by fasteners. This airtight device 8 is prior art and consists of a base 81 fixed to the end face of the set of connecting flanges 71, a first rotating ring 82, a clamp 83, a second rotating ring 84, and a pressure cap 85. A sealing ring (not shown in the figure) is provided between the clamp 83 and the rotating shaft 1. The clamp 83 is used to encircle the rotating shaft 1, providing a mounting carrier for the sealing ring, allowing the sealing ring to... It can stably contact the rotating shaft 1. The rotating ring 2 84 and rotating ring 1 82 work together to form a moving component for sealing adjustment. The sealing tightness is adjusted according to the air pressure change. The pressure cover 85 is used to press and fix the internal components of the air sealing device 8 to ensure that the position of each component is stable during operation. The middle part of the air sealing device 8 can be filled with compressed air through external equipment. The pressure generated by the compressed air pushes the clamp 83 to drive the sealing ring, thereby controlling the tightness of the sealing ring with the rotating shaft 1. Good sealing performance can be guaranteed under different working conditions.

[0030] Multiple sets of positioning screws 9 are connected between the two end connecting flanges 71 of the expansion joint 7. The positioning screws 9 play the role of positioning and connection and fixation, ensuring that the relative position of the connecting flanges 71 at both ends of the expansion joint 7 is stable. The two ends of the positioning screws 9 pass through the connecting flanges 71 and are threaded with nuts (not shown in the figure). A gasket is placed between the nut and the connecting flange 71. At the same time, the expansion joint 7 has a nitrogen purging port 10, which is used to introduce inert gas (nitrogen) to form a positive pressure environment inside the expansion joint 7, preventing air from entering the main unit and affecting the material quality when the packing seal 5 leaks slightly.

[0031] Furthermore, a secondary sealing assembly is connected to one end face of another set of connecting flanges 71. The secondary sealing assembly includes a stuffing box 12 connected to the other end face of the connecting flange 71. The stuffing box 12 is sleeved on the rotating shaft 1, and the stuffing box 12 has connecting flanges 2 at both ends. One end of the positioning screw 9 passes through the connecting flange 2 and is threaded with a nut 2 to facilitate the connection and fixation of the stuffing box 12 and the expansion joint 7. At the same time, an O-ring seal 11 is provided between the stuffing box 12 and the expansion joint 7. The O-ring seal 11 is partially embedded in the end face of the connecting flange 2 and the O-ring seal 11 plays a sealing role to prevent gas inside the expansion joint 7 or external medium from leaking at the connection between the stuffing box 12 and the expansion joint 7.

[0032] Meanwhile, a cooling jacket 13 is fitted around the outer periphery of the stuffing box 12. The cooling jacket 13 cools the stuffing box 12 and the internal packing seal 5 and other components through the internally circulating cooling water, so as to avoid the sealing performance and component life due to excessive temperature. The cooling jacket 13 has a cooling water inlet 4 and a cooling water outlet (not shown in the figure). The cooling water inlet 4 is used to introduce cooling water. After circulating in the cooling jacket 13, the cooling water flows out from the cooling water outlet to achieve heat exchange cooling. At the same time, a sealing copper sleeve 3 is fitted on the rotating shaft 1 inside the stuffing box 12. The sealing copper sleeve 3 can reduce the direct wear between the rotating shaft 1 and the packing seal 5 on the one hand, and also assist in the sealing function on the other hand.

[0033] Furthermore, a packing gland 6 is fixed to the cooling jacket 13 by bolts. The packing gland 6 is used to press the packing seal 5, so that the packing seal 5 fits tightly with the rotating shaft 1, ensuring the sealing effect. There is a packing gap (not shown in the figure) between the packing gland 6 and the stuffing box 12, and the packing seal 5 is in the packing gap. The packing seal 5 fills the gap between the rotating shaft 1 and the stuffing box 12 through its own compression deformation, preventing the medium from leaking.

[0034] like Figures 5-6 As shown, a dustproof assembly is provided on the connecting flange 71. The function of the dustproof assembly is to prevent external dust and other impurities from entering the connection gap between the airtight device 8 and the connecting flange 71. The dustproof assembly includes two sets of dustproof parts provided on the connecting flange 71. Each dustproof part includes two sets of symmetrically arranged mounting arc blocks 14 fixed to the connecting flange 71 by bolts. A hinge 15 is vertically arranged on the mounting arc block 14. The hinge 15 has a movable rotating part 16, and a dust cover 17 is fixed on the hinge 15. The dust cover 17 can rotate around the hinge 15 to realize the action of opening or closing. The dust cover 17 has a hollow columnar structure with half split.

[0035] The two sets of dust covers 17 are joined together to form a columnar structure that covers the gas-tight device 8, thereby blocking the connection gap between the gas-tight device 8 and the connecting flange 71. At the same time, a silicone sealing strip (not shown in the figure) is provided on the side of the two sets of dust covers 17 that are in contact with each other. The silicone sealing strip provides compression space when the two sets of dust covers 17 are rotated and opened, avoiding mutual interference when the dust covers 17 are rotated. On the other hand, when the two sets of dust covers 17 are in contact with each other, the silicone sealing strip is locally squeezed, which can fill the gap between the mating surfaces and further improve the dustproof sealing effect.

[0036] Meanwhile, two sets of opposing fixing parts are provided between the two sets of dust covers 17, at which point... Figure 5Based on this, the dust cover 17 located at the upper end is defined as dust cover one, and the dust cover 17 located at the lower end is defined as dust cover two. The fixing part includes a mounting base 18 fixed to the surface of dust cover two. The mounting base 18 has an integrally extended upward protrusion 19, and a gripping member 110 is movably connected to the protrusion 19 via a shaft. A connecting shaft 111 is movably and throughly disposed at the front end of the gripping member 110. A U-shaped hook 112 is connected to the connecting shaft 111. The shaft 111 serves to connect the grip 110 and the hook 112, allowing the hook 112 to move with the grip 110. At the same time, a fastener 113 adapted to the hook 112 is fixed on one surface of the dust cover. The fastener 113 cooperates with the hook 112 to form a locking structure, connecting and fixing the two sets of dust covers 17. The grip 110 is convenient for manual operation by the operator, and the connection or separation of the hook 112 and the fastener 113 can be controlled by rotating the grip 110.

[0037] Working principle: During operation, the rotating shaft 1 transmits power and rotates. Cooling water is introduced into the cooling jacket 13 through the cooling water inlet 4, circulates internally, and flows out from the cooling water outlet, cooling the stuffing box 12 and internal stuffing seal 5, etc., to prevent excessive temperature from affecting sealing performance and component life. The stuffing gland 6 presses the stuffing seal 5, causing the stuffing seal 5 to fill the gap between the rotating shaft 1 and the stuffing box 12 through its own compression deformation, achieving a primary seal. At the same time, the sealing copper sleeve 3 reduces direct wear between the rotating shaft 1 and the stuffing seal 5, and also assists in sealing.

[0038] Expansion joint 7 compensates for the thermal expansion and contraction of rotating shaft 1 caused by temperature changes, preventing shaft deformation from damaging the sealing structure. Nitrogen gas is introduced through nitrogen purging port 10, creating a positive pressure environment inside expansion joint 7. Even if there is a small leak in packing seal 5, the positive pressure nitrogen gas inside expansion joint 7 makes it difficult for external air to enter the main unit, preventing it from affecting the quality of materials; and O-ring seal 11 seals the connection between expansion joint 7 and stuffing box 12, further preventing gas or medium leakage.

[0039] The airtight sealing device 8 serves as a secondary seal, and its interior can be filled with compressed air. The air pressure pushes the clamp 83, controlling the tightness of the sealing ring between the clamp 83 and the rotating shaft 1, ensuring a good seal under different operating conditions. Furthermore, the two sets of dust covers 17 of the dustproof assembly are fitted onto the airtight sealing device 8, with silicone sealing strips filling the gap between the mating surfaces to prevent dust from entering the connection gap between the airtight sealing device 8 and the connecting flange 71. By operating the grip 110, the connection or separation of the hook 112 and the fastener 113 can be controlled, allowing the dust cover 17 to be fixed or opened. This facilitates equipment maintenance while continuously providing dust protection, ensuring the long-term stable operation of the sealing system.

[0040] The above description is merely a preferred embodiment of the present utility model and is not intended to limit the present utility model in any way. Although the present utility model has been disclosed above with reference to a preferred embodiment, it is not intended to limit the present utility model. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present utility model. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present utility model without departing from the scope of the present utility model shall still fall within the scope of the present utility model.

Claims

1. A high-temperature resistant rotary shaft seal, characterized in that: include A rotating shaft (1) is fitted with an expansion joint (7). The expansion joint (7) has connecting flanges (71) at both ends. One set of connecting flanges (71) has a secondary sealing assembly that provides a first seal for the rotating shaft (1) on its end face. The other set of connecting flanges (71) has a secondary sealing assembly that provides a second seal for the rotating shaft (1) on its other end face. A dustproof assembly is provided on the connecting flanges (71). The dustproof assembly is used to prevent external dust from entering the connection gap between the secondary sealing assembly and the connecting flanges (71). The dustproof assembly includes two sets of dustproof parts provided on the connecting flanges (71). Two sets of oppositely arranged fixing parts are provided between the two sets of dustproof parts.

2. The high-temperature resistant rotary shaft seal according to claim 1, characterized in that: The secondary sealing assembly includes an air-tight device (8) fixed to the end face of the first connecting flange (71). The air-tight device (8) consists of a base (81) fixed to the end face of the first connecting flange (71), a first rotating ring (82), a clamp (83), a second rotating ring (84), and a pressure cover (85). A sealing ring is provided between the clamp (83) and the rotating shaft (1).

3. The high-temperature resistant rotary shaft seal according to claim 2, characterized in that: The expansion joint (7) has multiple sets of positioning screws (9) connected between two connecting flanges (71). The two ends of the positioning screws (9) pass through the connecting flanges (71) and are threaded with nuts. A gasket is provided between the nuts and the connecting flanges (71). The expansion joint (7) has a nitrogen purging port (10) for introducing inert gas.

4. The high-temperature resistant rotary shaft seal according to claim 3, characterized in that: The secondary sealing assembly includes a stuffing box (12) connected to the other end face of the connecting flange (71). The stuffing box (12) is sleeved on the rotating shaft (1). The stuffing box (12) has connecting flanges (2) at both ends. One end of the positioning screw (9) passes through the connecting flange (2) and is threaded with a nut. An O-ring (11) is provided between the stuffing box (12) and the expansion joint (7). A portion of the O-ring (11) is embedded in the end face of the connecting flange (2).

5. A high-temperature resistant rotary shaft seal according to claim 4, characterized in that: The outer periphery of the stuffing box (12) is fitted with a cooling jacket (13), which has a cooling water inlet (4) and a cooling water outlet. The cooling water inlet (4) is used to introduce cooling water, and the cooling water circulates in the cooling jacket (13) and flows out from the cooling water outlet to achieve heat exchange cooling.

6. A high-temperature resistant rotary shaft seal according to claim 5, characterized in that: A sealing copper sleeve (3) is fitted on the rotating shaft (1) and inside the stuffing box (12). A packing gland (6) is fixed on the cooling jacket (13). There is a packing gap between the packing gland (6) and the stuffing box (12). A packing seal (5) is provided in the packing gap.

7. A high-temperature resistant rotary shaft seal according to claim 2, characterized in that: The dustproof part includes two sets of symmetrically arranged mounting arc blocks (14) fixed to the connecting flange (71). A hinge (15) is vertically arranged on the mounting arc block (14). The hinge (15) has a movable rotating part (16). A dust cover (17) is fixed on the hinge (15). The dust cover (17) is a hollow columnar structure with a split shape. The two sets of dust covers (17) are joined together to form a columnar structure to cover the airtight device (8). A silicone sealing strip is provided on the side of the two sets of dust covers (17) that are in contact with each other.

8. A high-temperature resistant rotary shaft seal according to claim 7, characterized in that: The dust cover (17) located at the upper end is defined as dust cover one, and the dust cover (17) located at the lower end is defined as dust cover two. The fixing part includes a mounting base (18) fixed on the surface of dust cover two. A protrusion (19) extends upward integrally on the mounting base (18). The protrusion (19) is movably connected to a grip (110) through a shaft. A connecting shaft (111) is movably provided through the front end of the grip (110). A U-shaped hook (112) is connected to the connecting shaft (111). A fastener (113) adapted to the hook (112) is fixed on the surface of dust cover one.

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