Multistage carbon ring shaft seal

Abstract

The utility model relates to the technical field of carbon ring shaft seals, and discloses a multistage carbon ring shaft seal which comprises a flange, two shells and a shaft sleeve, an oil seal channel is formed in the inner surface of one shell, an oil cylinder is fixedly communicated with the position, located at the oil seal channel, of the outer surface of the top of the shell, and a piston rod movably penetrates through the outer surface of the top of the oil cylinder. A piston disc is fixedly connected to the position, located in the oil cylinder, of the outer surface of the bottom of the piston rod, a first spring is fixedly connected to the outer surface of the rectangular seat, a limiting rod movably penetrates through the lateral outer surface of the rectangular seat, and a plurality of limiting holes are formed in the outer surface of the piston rod. The sealing oil is injected into the oil cylinder, the first spring is arranged to be matched with the limiting rod and the limiting hole, limiting of the piston rod is relieved, the piston rod drives the piston disc to inject the sealing oil into the gap between the carbon ring body and the shaft sleeve, gas media are blocked, and therefore additional equipment does not need to be added, and the sealing cost is reduced.

Description

Multi-stage carbon ring shaft seal Technical Field

[0001] This utility model relates to the field of carbon ring shaft seal technology, specifically to multi-stage carbon ring shaft seals. Background Technology

[0002] Multi-stage carbon ring shaft seals are sealing devices used for rotating shafts and are widely used in petrochemical, metallurgical, steam turbine, fan, generator, and compressor industries. Multi-stage carbon ring shaft seals utilize the sealing gas to form a gas film between the carbon graphite floating ring and the shaft. Through progressive throttling and pressure reduction, high-pressure gas is prevented from flowing to the low-pressure side. In the multi-stage structure, the gas passes sequentially through multiple carbon ring gaps; the pressure decreases with each stage of carbon ring passage, thus achieving a highly efficient seal.

[0003] In existing technologies, the pressure of the isolation gas needs to be greater than that of the leak-proof gas. At the same time, high-pressure isolation gas needs to be continuously injected into the sealing ring through the through hole during equipment operation. However, additional compression equipment is required to inject the gas flow during injection, which increases the sealing cost. Therefore, a multi-stage carbon ring shaft seal has been proposed. Summary of the Invention

[0004] In view of the shortcomings of the prior art, this utility model provides a multi-stage carbon ring shaft seal to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, this utility model provides the following technical solution: a multi-stage carbon ring shaft seal, comprising a flange, two outer shells, and a bushing. One of the outer shells has an oil seal channel on its inner surface. An oil cylinder is fixedly connected to the top outer surface of the outer shell at the oil seal channel. A piston rod movably passes through the top outer surface of the oil cylinder. A piston disc is fixedly connected to the bottom outer surface of the piston rod inside the oil cylinder. The piston disc movably fits against the inner wall of the oil cylinder. A rectangular seat is fixedly connected to the top outer surface of the oil cylinder. A first spring is fixedly connected to the outer surface of the rectangular seat. A limit rod movably passes through the lateral outer surface of the rectangular seat. Several limit holes are formed on the outer surface of the piston rod.

[0006] Furthermore, the inner wall of the outer shell is provided with multiple annular grooves, and carbon rings are provided inside the multiple annular grooves. Tension springs are provided outside the carbon rings in the two outer shells, and the tension springs are used to connect the corresponding carbon rings in the two outer shells.

[0007] Furthermore, the outer surface of the flange is provided with multiple screw holes, and the outer surface of the housing is provided with mounting holes, with bolts provided at the corresponding positions of the mounting holes and screw holes.

[0008] Furthermore, a positioning groove is provided on the inner side of the outer shell, and a positioning block that matches the positioning groove is fixedly connected to the outer surface of the bushing.

[0009] Furthermore, a spring seat is provided between each two adjacent carbon ring bodies, and a plurality of second springs are fixedly connected between the two spring seats.

[0010] Furthermore, an oil injection pipe is fixedly connected to the outer surface of the oil cylinder.

[0011] Furthermore, the oil cylinder is filled with sealing oil, which is glycerin.

[0012] Compared with the prior art, the beneficial effects of this utility model are:

[0013] 1. This multi-stage carbon ring shaft seal injects sealing oil into the oil cylinder. By setting a first spring in conjunction with a limiting rod and a limiting hole, the piston rod is released from its limit, allowing the piston rod to drive the piston disc to inject sealing oil into the gap between the carbon ring body and the shaft sleeve, thus blocking the gas medium. This eliminates the need for additional equipment and reduces sealing costs.

[0014] 2. When assembling this multi-stage carbon ring shaft seal, the bolts are screwed into the mounting holes and into the bolt holes of the flange to install the outer shell and the flange. The positioning block of the shaft sleeve is aligned with the positioning groove, and the shaft sleeve is installed inside the outer shell. The shaft sleeve is then placed on the shaft, and the flange is installed. The structure is simple, and the installation and disassembly are convenient and efficient. Attached Figure Description

[0015] Figure 1 is a front view of the structure of this utility model;

[0016] Figure 2 is a side sectional view of the present invention.

[0017] Figure 3 is an enlarged structural schematic diagram of point A in Figure 1 of this utility model;

[0018] Figure 4 is an enlarged structural schematic diagram of section B in Figure 2 of this utility model.

[0019] In the diagram: 1. Flange; 2. Housing; 3. Bushing; 4. Oil cylinder; 5. Piston rod; 6. Rectangular seat; 7. First spring; 8. Limiting rod; 9. Limiting hole; 10. Annular groove; 11. Carbon ring; 12. Spring seat; 13. Second spring; 14. Positioning block; 15. Bolt. Detailed Implementation

[0020] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0021] Example 1:

[0022] Referring to Figures 1-4, this utility model provides a technical solution: a multi-stage carbon ring shaft seal, including a flange 1, two outer shells 2, and a bushing 3. One of the outer shells 2 has an oil seal channel on its inner surface. An oil cylinder 4 is fixedly connected to the oil seal channel on the top outer surface of the outer shell 2. A piston rod 5 movably passes through the top outer surface of the oil cylinder 4. A piston disc is fixedly connected to the bottom outer surface of the piston rod 5 inside the oil cylinder 4. The piston disc movably fits against the inner wall of the oil cylinder 4. A rectangular seat 6 is fixedly connected to the top outer surface of the oil cylinder 4. A first spring 7 is fixedly connected to the outer surface of the rectangular seat 6. A limiter passes through the lateral outer surface of the rectangular seat 6. The piston rod 5 has several limiting holes 9 on its outer surface. Specifically, pulling the limiting rod 8 causes the first spring 7 to deform, causing the limiting rod 8 to disengage from the limiting hole 9 and releasing the piston rod 5 from its limit. By pressing the piston rod 5, the piston rod 5 is pushed down to press the piston, which injects sealing oil into the oil seal channel. When the sealing oil is injected into the oil seal channel, it flows to the carbon rings 11 on both sides, thereby sealing the gap between the carbon rings 11 and the bushing 3. Thus, only the sealing oil needs to be added to the oil cylinder 4 periodically to block the gas medium, thereby eliminating the need for additional equipment and reducing sealing costs.

[0023] In this embodiment, the inner wall of the outer shell 2 is provided with a plurality of annular grooves 10, and carbon rings 11 are provided inside the plurality of annular grooves 10. A tension spring is provided outside the carbon rings 11 in the two outer shells 2. The tension spring is used to connect the corresponding carbon rings 11 in the two outer shells 2. Specifically, the carbon rings 11 are provided inside the annular grooves 10 and are connected to the corresponding carbon rings 11 in the two outer shells 2 by the tension spring.

[0024] In this embodiment, the outer surface of the flange 1 is provided with multiple screw holes, and the outer surface of the housing 2 is provided with mounting holes. Bolts 15 are provided at the corresponding positions of the mounting holes and screw holes. Specifically, the mounting holes are aligned with the screw holes, and the bolts 15 are inserted into the mounting holes and screwed into the screw holes to connect the housing 2 and the flange 1.

[0025] In this embodiment, a positioning groove is provided on the inner side of the outer shell 2, and a positioning block 14 that matches the positioning groove is fixedly connected to the outer surface of the bushing 3. Specifically, the positioning block 14 is inserted into the positioning groove to facilitate the assembly of the bushing 3 and the outer shell 2.

[0026] In this embodiment, a spring seat 12 is provided between each of two adjacent carbon ring bodies 11, and a plurality of second springs 13 are fixedly connected between the two spring seats 12. Specifically, the second springs 13 provide a suitable axial elastic force to the carbon ring body 11.

[0027] In this embodiment, an oil injection pipe is fixedly connected to the outer surface of the oil cylinder 4. Specifically, sealing oil can be injected into the oil cylinder 4 by opening the sealing cap outside the oil injection pipe.

[0028] In this embodiment, sealing oil is provided inside the oil cylinder 4. The sealing oil is glycerin. Specifically, glycerin has poor fluidity and high viscosity. In addition, other oils with poor fluidity and high viscosity can also be used as sealing oil.

[0029] Working principle: In use, the bushing 3 is placed on the shaft, and the sealing carbon ring is installed through the flange 1. Pulling the limiting rod 8 causes the first spring 7 to deform, causing the limiting rod 8 to disengage from the limiting hole 9, releasing the piston rod 5 from its limit. By pressing the piston rod 5, the piston rod 5 is pushed down, causing the sealing oil to be injected into the oil seal channel. When the sealing oil is injected into the oil seal channel, it flows to the carbon rings 11 on both sides, thereby sealing the gap between the carbon rings 11 and the bushing 3. Thus, only the sealing oil needs to be added to the oil cylinder 4 periodically to block the gas medium, thereby eliminating the need for additional equipment and reducing sealing costs.

[0030] When assembling the device, the bolts 15 are screwed into the mounting holes and into the bolt holes of the flange 1 to install the housing 2 and the flange 1. The positioning block 14 of the bushing 3 is aligned with the positioning groove, the bushing 3 is installed inside the housing 2, the bushing 3 is placed on the shaft, and the flange 1 is installed to install the device.

[0031] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A multi-stage carbon ring shaft seal, comprising a flange (1), two outer shells (2) and a shaft sleeve (3), characterized in that: One of the outer shells (2) has an oil seal channel on its inner surface. The top outer surface of the outer shell (2) is fixedly connected to an oil cylinder (4) at the oil seal channel. A piston rod (5) is movably passed through the top outer surface of the oil cylinder (4). A piston disc is fixedly connected to the bottom outer surface of the piston rod (5) inside the oil cylinder (4). The piston disc is movably fitted to the inner wall of the oil cylinder (4). A rectangular seat (6) is fixedly connected to the top outer surface of the oil cylinder (4). A first spring (7) is fixedly connected to the outer surface of the rectangular seat (6). A limit rod (8) movably passes through the lateral outer surface of the rectangular seat (6). Several limit holes (9) are opened on the outer surface of the piston rod (5).

2. The multi-stage carbon ring shaft seal according to claim 1, characterized in that: The inner wall of the outer shell (2) is provided with a plurality of annular grooves (10), and carbon ring bodies (11) are provided inside the plurality of annular grooves (10). A tension spring is provided outside the carbon ring bodies (11) in the two outer shells (2), and the tension spring is used to connect the corresponding carbon ring bodies (11) in the two outer shells (2).

3. The multi-stage carbon ring shaft seal according to claim 1, characterized in that: The outer surface of the flange (1) is provided with a plurality of screw holes, and the outer surface of the housing (2) is provided with mounting holes, and bolts (15) are provided at the mounting holes and screw holes respectively.

4. The multi-stage carbon ring shaft seal according to claim 1, characterized in that: The outer casing (2) has a positioning groove on its inner side, and the outer surface of the bushing (3) is fixedly connected with a positioning block (14) that is adapted to the positioning groove.

5. The multi-stage carbon ring shaft seal according to claim 2, characterized in that: A spring seat (12) is provided between each of the two adjacent carbon ring bodies (11), and a plurality of second springs (13) are fixedly connected between the two spring seats (12).

6. The multi-stage carbon ring shaft seal according to claim 1, characterized in that: An oil injection pipe is fixedly connected to the outer surface of the oil cylinder (4).

7. The multi-stage carbon ring shaft seal according to claim 1, characterized in that: The oil cylinder (4) is filled with sealing oil, which is glycerin.

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