Double-layer mechanical seal housing structure combined with labyrinth seal

Abstract

The invention discloses a double-layer mechanical seal housing structure combined with labyrinth seal. Most of existing mechanical seal housings are of a single-layer structure, only have a basic protection function, cannot solve the influence of negative pressure on the sealing performance, and are inconvenient to replace on the premise that the main body structure of equipment is not changed. The mechanical sealing device comprises a gear box body bearing seat, inner hexagon bolts, an upper mechanical sealing inner cover shell, hexagon screws, an upper mechanical sealing outer cover shell, a lower mechanical sealing inner cover shell and a lower mechanical sealing outer cover shell. The upper mechanical seal inner housing is matched with a gear box body bearing seat and is fixedly connected with the gear box body bearing seat through a hexagon socket screw; the upper mechanical sealing outer housing is matched with an outer flange of the upper mechanical sealing inner housing and is fixedly connected with the upper mechanical sealing inner housing through a hexagon screw; the lower mechanical seal inner housing is matched with the gear box body bearing seat and is fixedly connected with the gear box body bearing seat through a hexagon socket screw; and the lower mechanical sealing outer housing is matched with an outer side flange of the lower mechanical sealing inner housing. The invention is applied to the field of gearbox mechanical sealing.

Description

Technical Field

[0001] This invention relates to the field of mechanical seal housing structures, and more specifically to a double-layer mechanical seal housing structure incorporating a labyrinth seal. Background Technology

[0002] During gearbox operation, mechanical seals are commonly used at the high-speed ends of the input and output shafts to prevent oil leakage. However, mechanical seals require extremely high installation precision. Their internal oil return holes are very small. If problems such as coaxiality deviation or improper seal compression occur during installation, or if the seal wears out after long-term use, the sealing performance can easily deteriorate, leading to oil leakage at the shaft ends.

[0003] Meanwhile, some gearboxes have a closed outer structure, which creates a negative pressure environment outside the mechanical seal when adjacent equipment rotates at high speed. This negative pressure can exacerbate the leakage of the mechanical seal and even lead to seal failure. The leaked lubricating oil or oil mist may enter the interior of surrounding equipment, not only contaminating equipment components but also increasing the risk of equipment failure, posing a serious safety hazard in the long term.

[0004] Currently, most existing mechanical seal housings are single-layer structures, providing only basic protection. They cannot address the impact of negative pressure on sealing performance and are not easy to replace without altering the main structure of the equipment, making it difficult to meet the requirements for sealing reliability and ease of installation in practical applications. Summary of the Invention

[0005] In order to address the problem that most existing mechanical seal housings are single-layer structures that only provide basic protection and cannot solve the impact of negative pressure on sealing performance, this invention provides a double-layer mechanical seal housing structure that combines a labyrinth seal.

[0006] The technical solution of this invention is:

[0007] A double-layer mechanical seal housing structure incorporating a labyrinth seal includes a gearbox bearing housing, hexagonal socket head cap screws, an upper mechanical seal inner housing, hexagonal screws, an upper mechanical seal outer housing, a lower mechanical seal inner housing, and a lower mechanical seal outer housing. The upper mechanical seal inner housing mates with the inner locating of the gearbox bearing housing via an outer locating joint and is fixedly connected by hexagonal socket head cap screws. The upper mechanical seal outer housing mates with the inner locating of the outer flange of the upper mechanical seal inner housing via an outer locating joint and is fixedly connected by hexagonal screws. The lower mechanical seal inner housing mates with the inner locating of the gearbox bearing housing via an outer locating joint and is fixedly connected by hexagonal socket head cap screws. The lower mechanical seal outer housing mates with the inner locating of the outer flange of the lower mechanical seal inner housing via an outer locating joint and is fixedly connected by hexagonal screws.

[0008] Furthermore, it also includes screw plugs and mounting holes;

[0009] The outer flanges of both the upper mechanical seal inner cover and the lower mechanical seal inner cover are provided with mounting holes. The hexagonal socket bolts pass through the mounting holes for fixing. The plugs are installed in the mounting holes to isolate the air pressure between the upper mechanical seal inner cover and the upper mechanical seal outer cover, and between the lower mechanical seal inner cover and the lower mechanical seal outer cover.

[0010] Furthermore, this also includes labyrinth seals and gearbox shaft end flanges;

[0011] The labyrinth seal is fixedly connected to the gearbox shaft end flange, and the labyrinth seal and the gearbox shaft end flange form a sealing structure to reduce the negative pressure inside the casing.

[0012] Furthermore, the outer circumference of the mounting flanges of the upper mechanical seal inner cover, lower mechanical seal inner cover, upper mechanical seal outer cover, and lower mechanical seal outer cover are all provided with irregularly shaped mounting holes. These irregularly shaped mounting holes are used to adapt to the bolts of the external equipment cover, enabling in-situ replacement.

[0013] Furthermore, it also includes a screw plug baffle;

[0014] The screw plug baffle is welded to the inner side of the upper mechanical seal inner cover and the lower mechanical seal inner cover, and is located directly below the mounting hole to prevent the screw plug from loosening and falling into the cover.

[0015] Furthermore, the screw plug baffle has a three-section structure. The three baffles are evenly distributed along the inner circumference of the upper mechanical seal inner cover and the lower mechanical seal inner cover, and there is a gap between adjacent baffles. This reduces the processing difficulty while ensuring the effective prevention of bolt falling off and ensures the smoothness of oil return.

[0016] Furthermore, both the upper and lower mechanical seal outer covers are provided with oil return ports at their inner bottoms. These oil return ports are connected to an oil collection cup via pipes to collect lubricating oil leaking from the mechanical seal.

[0017] Furthermore, the fit clearance between the upper mechanical seal inner cover and the gearbox bearing seat, and the fit clearance between the lower mechanical seal inner cover and the gearbox bearing seat are both 0.02-0.05 mm.

[0018] Furthermore, the labyrinth seal has rectangular teeth with a tooth height of 5-8 mm and a tooth thickness of 2-3 mm, and the gap between the labyrinth seal and the end face of the lower mechanical seal outer casing is 0.1-0.2 mm.

[0019] Furthermore, the upper mechanical seal inner cover, lower mechanical seal inner cover, upper mechanical seal outer cover, and lower mechanical seal outer cover are all made of 304 stainless steel, and their surfaces are polished.

[0020] Furthermore, the stop fit clearance between the upper mechanical seal inner cover and the upper mechanical seal outer cover, and the stop fit clearance between the lower mechanical seal inner cover and the lower mechanical seal outer cover are both 0.03-0.06mm, and the mating surfaces are coated with oil-resistant sealant with a thickness of 0.01-0.02mm to enhance the sealing performance between the inner and outer covers.

[0021] Compared with the prior art, the present invention has the following advantages:

[0022] The invention features oil return ports at the bottom of both the upper and lower mechanical seal outer housings, allowing for the collection of leaked lubricating oil into an oil collection cup when the mechanical seal leaks. Labyrinth seal structures on the edges of the upper and lower mechanical seal outer housings reduce the negative pressure inside the housings, minimizing its impact on the mechanical seal. Furthermore, these seals effectively prevent leaked lubricating oil or oil mist from entering other equipment when the mechanical seal leaks.

[0023] This invention aims to solve the problems of leakage due to improper installation, wear, and negative pressure in existing mechanical seals. It increases oil return, isolates pressure differential, and prevents lubricating oil from leaking to the outside. Furthermore, the double-layer cover is easy to install, has a compact structure, and can be replaced in situ on existing equipment.

[0024] This invention adds a gearbox shaft end flange to the traditional mechanical seal housing for mounting and fixing the upper and lower mechanical seal outer housings. In addition to collecting lubricating oil leaking from the mechanical seal end, the upper and lower mechanical seal inner housings also have a labyrinth seal structure on the edge to reduce the negative pressure inside the housing and reduce the impact of negative pressure on the mechanical seal, thereby reducing the phenomenon of lubricating oil or oil mist entering other equipment due to air pressure difference. Attached Figure Description

[0025] Figure 1 This is a general cross-sectional view of the installation of the double-layer mechanical seal housing of the present invention;

[0026] Figure 2 This is a cross-sectional view of the upper part of the double-layer mechanical seal housing of the present invention.

[0027] Figure 3 This is a cross-sectional view of the lower part of the double-layer mechanical seal housing of the present invention.

[0028] Figure 4 This is a view of the end face of the upper and lower mechanical seal inner housings of the present invention.

[0029] Figure 5 This is a view of the end face of the upper and lower mechanical seal outer casing of the present invention;

[0030] In the diagram: 1. Gearbox housing bearing seat, 2. Socket head bolt, 3. Upper mechanical seal inner cover, 4. Hex bolt, 5. Upper mechanical seal outer cover, 6. Plug, 7. Plug baffle, 8. Gearbox shaft end flange, 9. Labyrinth seal, 10. Lower mechanical seal inner cover, 11. Lower mechanical seal outer cover, 12. Mounting hole. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments will be clearly and completely described below with reference to the accompanying drawings. The following embodiments are used to illustrate the present invention, but are not intended to limit the scope of the present invention. Specific implementation method one:

[0033] Combination Figure 1 — Figure 5 This embodiment describes a double-layer mechanical seal housing structure incorporating a labyrinth seal, comprising a gearbox bearing housing 1, hexagonal bolts 2, an upper mechanical seal inner housing 3, hexagonal screws 4, an upper mechanical seal outer housing 5, a lower mechanical seal inner housing 10, and a lower mechanical seal outer housing 11. The upper mechanical seal inner housing 3 engages with the inner locating of the gearbox bearing housing 1 via an outer locating joint and is fixedly connected by the hexagonal bolts 2. The upper mechanical seal outer housing 5 engages with the inner locating of the outer flange of the upper mechanical seal inner housing 3 via an outer locating joint and is fixedly connected by the hexagonal screws 4. The lower mechanical seal inner housing 10 engages with the inner locating of the gearbox bearing housing 1 via an outer locating joint and is fixedly connected by the hexagonal bolts 2. The lower mechanical seal outer housing 11 engages with the inner locating of the outer flange of the lower mechanical seal inner housing 10 via an outer locating joint and is fixedly connected by the hexagonal screws 4.

[0034] The overall structure is based on the upper mechanical seal inner cover 3, the upper mechanical seal outer cover 5, the lower mechanical seal inner cover 10, and the lower mechanical seal outer cover, which are symmetrically arranged and fixed to the gearbox bearing seat 1.

[0035] Both the upper mechanical seal inner cover 3 and the lower mechanical seal inner cover 10 are fitted with the inner stop of the gearbox bearing seat 1 through the outer stop (the fit clearance is strictly controlled within 0.02-0.05mm to ensure sealing accuracy). Then, the inner cover is fixed to the bearing seat by passing the hexagonal bolts 2 through the mounting holes 12 of the outer flange of the inner cover. Specific Implementation Method Two:

[0037] Combination Figure 1 — Figure 5 This embodiment describes a double-layer mechanical seal housing structure that incorporates a labyrinth seal, and further includes a screw plug 6 and a mounting hole 12.

[0038] The outer flanges of the upper mechanical seal inner cover 3 and the lower mechanical seal inner cover 10 are both provided with mounting holes 12. The hexagonal socket bolts 2 pass through the mounting holes 12 for fixing. The screw plugs 6 are installed in the mounting holes 12 to isolate the air pressure between the upper mechanical seal inner cover 3 and the upper mechanical seal outer cover 5, and between the lower mechanical seal inner cover 10 and the lower mechanical seal outer cover 11.

[0039] The screw plug 6 is installed in the mounting hole 12, which can isolate the air pressure between the inner and outer shells and prevent the air pressure difference from affecting the seal; the screw plug baffle 7 is welded to the inner side of the inner shell, directly below the mounting hole 12, and adopts a three-section structure.

[0040] The three sections of the screw plug baffle 7 are evenly distributed along the circumference, which reduces the processing difficulty while ensuring the effective prevention of bolt falling off and ensuring the smooth flow of oil return. Specific implementation method three:

[0042] Combination Figure 1 — Figure 5 This embodiment describes a double-layer mechanical seal housing structure combined with a labyrinth seal, which further includes a labyrinth seal 9 and a gearbox shaft end flange 8.

[0043] The labyrinth seal 9 is fixedly connected to the gearbox shaft end flange 8, and the labyrinth seal 9 and the gearbox shaft end flange 8 form a sealing structure to reduce the negative pressure inside the casing.

[0044] The labyrinth seal 9 is fixedly connected to the gearbox shaft end flange 8 to form a sealing structure. Its tooth shape is rectangular, with a tooth height of 5-8mm and a tooth thickness of 2-3mm. The gap between it and the end face of the lower mechanical seal outer cover 11 is 0.1-0.2mm, which can effectively weaken the negative pressure inside the cover and reduce the impact of negative pressure on the mechanical seal. Specific implementation method four:

[0046] Combination Figure 1 — Figure 5 This embodiment describes a double-layer mechanical seal housing structure combined with a labyrinth seal, which also includes a screw plug baffle 7.

[0047] The screw plug baffle 7 is welded to the inner side of the upper mechanical seal inner cover 3 and the lower mechanical seal inner cover 10, and is located directly below the mounting hole 12 to prevent the screw plug 6 from loosening and falling into the cover. Specific implementation method five:

[0049] Combination Figure 1 — Figure 5This embodiment describes a double-layer mechanical seal housing structure combined with a labyrinth seal. The screw plug baffle 7 has a three-section structure. The three baffles are evenly distributed along the inner circumference of the upper mechanical seal inner housing 3 and the lower mechanical seal inner housing 10, and there is a gap between adjacent baffles. This reduces the processing difficulty while ensuring the function of effectively preventing bolts from falling off and ensuring the smoothness of oil return. Specific implementation method six:

[0051] Combination Figure 1 — Figure 5 This embodiment describes a double-layer mechanical seal housing structure combined with a labyrinth seal. The inner bottom of both the upper mechanical seal outer housing 5 and the lower mechanical seal outer housing 11 are provided with oil return ports. The oil return ports are connected to an oil collection cup through pipes to collect lubricating oil leaking from the mechanical seal. Specific implementation method seven:

[0053] Combination Figure 1 — Figure 5 This embodiment describes a double-layer mechanical seal housing structure combined with a labyrinth seal. The locating clearance between the upper mechanical seal inner housing 3 and the gearbox bearing seat 1, and the locating clearance between the lower mechanical seal inner housing 10 and the gearbox bearing seat 1, are both 0.02-0.05 mm. Detailed implementation method eight:

[0055] Combination Figure 1 — Figure 5 This embodiment describes a double-layer mechanical seal housing structure combined with a labyrinth seal. The labyrinth seal 9 has rectangular teeth with a tooth height of 5-8 mm and a tooth thickness of 2-3 mm. The gap between the labyrinth seal 9 and the end face of the lower mechanical seal outer housing 11 is 0.1-0.2 mm. Specific implementation method nine:

[0057] Combination Figure 1 — Figure 5 This embodiment describes a double-layer mechanical seal housing structure combining a labyrinth seal. The upper mechanical seal inner housing 3, the lower mechanical seal inner housing 10, the upper mechanical seal outer housing 5, and the lower mechanical seal outer housing 11 are all made of 304 stainless steel and have been polished.

[0058] The present invention comprises a double-layer cover structure consisting of an upper mechanical seal outer cover 5 and a lower mechanical seal outer cover 11, an upper mechanical seal inner cover 3 and a lower mechanical seal inner cover 10. The upper mechanical seal outer cover 5 and the lower mechanical seal outer cover 11 can collect the lubricating oil leaking from the mechanical seal, preventing the lubricating oil from leaking directly to the outside.

[0059] The labyrinth seal structure effectively reduces the negative pressure inside the housing, minimizing its impact on the mechanical seal, while also preventing oil mist diffusion. This dual protection significantly improves the reliability of the seal.

[0060] The upper mechanical seal outer cover 5, the lower mechanical seal outer cover 11, the upper mechanical seal inner cover 3, and the lower mechanical seal inner cover 10 are fixed with stop-positioning bolts, ensuring precise installation and positioning.

[0061] The irregularly shaped mounting hole structure is compatible with existing equipment and can directly replace the original cover in situ without modifying the equipment, reducing installation costs and time.

[0062] The three-section design of the screw plug baffle is evenly distributed along the inner circumference of the upper mechanical seal inner cover 3 and the lower mechanical seal inner cover 10, with gaps between adjacent baffles to avoid interference with the internal structure of the cover. This design not only prevents equipment accidents caused by screw plug detachment but also avoids structural interference, ensuring safe equipment operation. The overall structure is compact, occupies little space, and is suitable for the confined installation environment of gearboxes.

[0063] While the invention has been described herein with reference to specific embodiments, it should be understood that these embodiments are merely examples of the principles and applications of the invention. Therefore, it should be understood that many modifications can be made to the exemplary embodiments, and other arrangements can be designed without departing from the spirit and scope of the invention as defined by the appended claims. It should be understood that different dependent claims and features described herein can be combined in ways different from those described in the original claims. It is also understood that features described in conjunction with individual embodiments can be used in other described embodiments.

Claims

1. A double-layer mechanical seal housing structure incorporating a labyrinth seal, characterized in that, Includes gearbox bearing housing (1), internal hex bolt (2), upper mechanical seal inner cover (3), hex screw (4), upper mechanical seal outer cover (5), lower mechanical seal inner cover (10) and lower mechanical seal outer cover (11); The upper mechanical seal inner cover (3) is fitted with the inner stop of the gearbox bearing seat (1) through the outer stop and is fixedly connected by hexagonal bolts (2); the upper mechanical seal outer cover (5) is fitted with the inner stop of the outer flange of the upper mechanical seal inner cover (3) through the outer stop and is fixedly connected by hexagonal screws (4); the lower mechanical seal inner cover (10) is fitted with the inner stop of the gearbox bearing seat (1) through the outer stop and is fixedly connected by hexagonal bolts (2); The lower mechanical seal outer cover (11) is fitted with the inner stop of the outer flange of the lower mechanical seal inner cover (10) through the outer stop, and is fixedly connected by hexagonal screws (4).

2. The double-layer mechanical seal housing structure combining a labyrinth seal according to claim 1, characterized in that, It also includes a screw plug (6) and a mounting hole (12); The outer flanges of the upper mechanical seal inner cover (3) and the lower mechanical seal inner cover (10) are provided with mounting holes (12). The hexagonal bolts (2) pass through the mounting holes (12) for fixing. The plugs (6) are installed in the mounting holes (12) to isolate the air pressure between the upper mechanical seal inner cover (3) and the upper mechanical seal outer cover (5), and between the lower mechanical seal inner cover (10) and the lower mechanical seal outer cover (11).

3. The double-layer mechanical seal housing structure combining a labyrinth seal according to claim 1, characterized in that, It also includes a labyrinth seal (9) and a gearbox shaft end flange (8); The labyrinth seal (9) is fixedly connected to the gearbox shaft end flange (8), and the labyrinth seal (9) and the gearbox shaft end flange (8) form a sealing structure to reduce the negative pressure inside the cover.

4. The double-layer mechanical seal housing structure combined with a labyrinth seal according to claim 2, characterized in that, It also includes a screw plug baffle (7); The screw plug baffle (7) is welded to the inner side of the upper mechanical seal inner cover (3) and the lower mechanical seal inner cover (10), and is located directly below the mounting hole (12) to prevent the screw plug (6) from loosening and falling into the cover.

5. The double-layer mechanical seal housing structure combined with a labyrinth seal according to claim 4, characterized in that, The screw plug baffle (7) has a three-section structure. The three baffles are evenly distributed along the inner circumference of the upper mechanical seal inner cover (3) and the lower mechanical seal inner cover (10), and there is a gap between adjacent baffles to prevent the bolts from falling off and to ensure the smooth flow of oil return.

6. The double-layer mechanical seal housing structure combining a labyrinth seal according to claim 1, characterized in that, The inner bottom of both the upper mechanical seal outer cover (5) and the lower mechanical seal outer cover (11) are provided with oil return ports, which are connected to the oil collection cup through pipes to collect lubricating oil leaking from the mechanical seal.

7. The double-layer mechanical seal housing structure combining a labyrinth seal according to claim 1, characterized in that, The locating clearance between the upper mechanical seal inner cover (3) and the gearbox bearing seat (1), and the locating clearance between the lower mechanical seal inner cover (10) and the gearbox bearing seat (1) are both 0.02-0.05 mm.

8. The double-layer mechanical seal housing structure combined with a labyrinth seal according to claim 3, characterized in that, The labyrinth seal (9) has a rectangular tooth shape, a tooth height of 5-8 mm, a tooth thickness of 2-3 mm, and a gap of 0.1-0.2 mm between the labyrinth seal (9) and the end face of the lower mechanical seal outer cover (11).

9. The double-layer mechanical seal housing structure combining a labyrinth seal according to claim 1, characterized in that, The upper mechanical seal inner cover (3), the lower mechanical seal inner cover (10), the upper mechanical seal outer cover (5) and the lower mechanical seal outer cover (11) are all made of 304 stainless steel and have been polished.

10. The double-layer mechanical seal housing structure combined with a labyrinth seal according to claim 9, characterized in that, The locating clearance between the upper mechanical seal inner cover (3) and the upper mechanical seal outer cover (5), and the locating clearance between the lower mechanical seal inner cover (10) and the lower mechanical seal outer cover (11) are both 0.03-0.06 mm, and the mating surfaces are all coated with oil-resistant sealant with a thickness of 0.01-0.02 mm to enhance the sealing performance between the inner and outer covers.

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