Marine anti-sand sealing assembly and gear box

Abstract

The present invention discloses a marine anti-mud seal assembly and a gearbox, which include a first sealing portion, a second sealing portion, an oil seal, an outer sleeve portion and an inner sleeve portion. The present invention adopts a conical surface as a sealing surface, and the first sealing surface and the second sealing surface can block most of the mud and sand from entering. When a small amount of mud and sand enters the gap between the first sealing surface and the second sealing surface, since the second sealing surface rotates with the propeller shaft, under the action of centrifugal force, mud and sand with a heavier specific gravity are more easily thrown out of the gap than water, so that the cooperation between the outer sleeve portion and the inner sleeve portion can block most of the mud and sand from entering. Therefore, compared with the prior art, the present invention can have a more stable seal and a longer service life.

Description

Technical Field

[0001] The invention relates to the field of marine equipment, in particular to a marine anti-sand sealing component and a gear box. Background Art

[0002] There is a lot of silt in offshore areas and ports. When tugboats operate in these areas for a long time, a large amount of silt will cause the steering propellers and propellers to be affected by it, especially the skeleton oil seals used for sealing. Staying in waters with a lot of silt for a long time will greatly affect the service life of the skeleton oil seals.

[0003] In sediment-free waters, the skeleton oil seal can provide reliable sealing for a long time, but if there is sediment, the sediment will enter the gap between the skeleton oil seal and the propeller shaft, acting as an abrasive, greatly increasing the wear rate of the skeleton oil seal. If the skeleton oil seal is not replaced in time after failure, the sediment and seawater will enter the gearbox, causing serious damage to the internal structure of the gearbox. Summary of the invention

[0004] The purpose of the invention is to provide a marine anti-sand sealing component.

[0005] To achieve the above-mentioned purpose, the technical solution adopted by the present invention is: a marine anti-mud and sand sealing assembly, which includes an annular first sealing portion fixedly connected to the gear box, an annular second sealing portion arranged on the outer periphery of the propeller shaft, and at least one oil seal arranged between the first sealing portion and the second sealing portion, and it also includes an outer sleeve portion arranged on the first sealing portion and an inner sleeve portion arranged on the second sealing portion, the outer sleeve portion has a first sealing surface, the inner sleeve portion has a second sealing surface that cooperates with the first sealing surface, and the first sealing surface and the second sealing surface are both conical surfaces.

[0006] Preferably, the inner sleeve further comprises a contact portion extending obliquely outward in a sheet shape, and the second sealing surface is located on the outside of the contact portion.

[0007] Further preferably, the inner sleeve portion further includes a guide portion extending outwardly perpendicular to the axial direction of the propeller shaft, and the outer sleeve portion is provided with a guide groove that cooperates with the guide portion.

[0008] Further preferably, the angle between the abutting portion and the guiding portion is an acute angle.

[0009] Preferably, the outer sleeve is arranged close to the outer end of the first sealing portion, and the first sealing portion is provided with an annular sealing cover for fixing the outer sleeve.

[0010] Further preferably, the sealing cover is detachably connected to the first sealing portion via bolts.

[0011] Preferably, a first sealing ring is provided between the outer sleeve and the first sealing portion.

[0012] Preferably, the inner sleeve portion and the second sealing portion are interference fit, and a second sealing ring is provided between the inner sleeve portion and the second sealing portion.

[0013] Preferably, the inner sleeve is made of stainless steel, and the outer sleeve is made of polytetrafluoroethylene.

[0014] A gear box is provided with the above-mentioned marine anti-sand sealing assembly.

[0015] Due to the application of the above technical solution, the present invention has the following advantages compared with the prior art:

[0016] Since the present invention uses a conical surface as a sealing surface, the first sealing surface and the second sealing surface can block most of the mud and sand from entering. When a small amount of mud and sand enters the gap between the first sealing surface and the second sealing surface, the second sealing surface rotates with the propeller shaft, and the second sealing surface drives the mud and sand and water between the first sealing surface and the second sealing surface to rotate in a circle. Under the action of centrifugal force, the mud and sand with a heavier specific gravity are easier to be thrown out of the gap than water, so that the cooperation of the outer sleeve and the inner sleeve can block most of the mud and sand from entering, and then the subsequent oil seal blocks water from entering the gear box to complete the sealing. The service life of the oil seal can be greatly extended after it is not affected by mud and sand. Therefore, compared with the prior art, the present invention can have a more stable seal and a longer service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Attached Figure 1 is a cross-sectional view of a gearbox seal assembly;

[0018] Attached Figure 2 It is a partial enlarged schematic diagram of the sealing component;

[0019] Attached Figure 3 is a schematic diagram of the cross section of the outer jacket;

[0020] Attached Figure 4 It is a schematic diagram of the cross section of the inner sleeve.

[0021] In the above drawings: 1. propeller shaft; 2. gearbox housing; 3. first sealing part; 4. second sealing part; 5. oil seal; 6. outer sleeve; 61. first sealing surface; 62. guide groove; 63. first sealing ring; 7. inner sleeve; 71. second sealing surface; 72. interference part; 73. guide part; 74. second sealing ring; 8. cover. DETAILED DESCRIPTION

[0022] The present invention will be further described below in conjunction with the embodiments shown in the accompanying drawings:

[0023] See attached Figure 1-2As shown, a marine gearbox adopts a marine anti-mud seal assembly to seal the gap between the propeller shaft 1 and the gearbox housing 2. The seal assembly includes an annular first seal portion 3 fixedly connected to the gearbox, an annular second seal portion 4 arranged on the outer periphery of the propeller shaft 1, three oil seals 5 arranged between the first seal portion 3 and the second seal portion 4, an outer sleeve portion 6 clamped on the inner wall of the first seal portion 3 and an inner sleeve portion 7 fixedly arranged on the outer periphery of the second seal portion 4. The outer sleeve portion 6 and the inner sleeve portion 7 are arranged on the outside of the gearbox, and when combined, they prevent mud and water from entering the oil seal 5.

[0024] In this embodiment, the first sealing part 3 is the end cover of the gear box, the second sealing part 4 is a sleeve fixed on the propeller shaft 1, the outer sleeve 6 is made of polytetrafluoroethylene material, and the inner sleeve 7 is made of 316L stainless steel. Polytetrafluoroethylene and 316L stainless steel have a certain sealing performance after contacting each other, and both polytetrafluoroethylene and 316L stainless steel have good wear resistance. When mud and sand enter the gap between the outer sleeve 6 and the inner sleeve 7 with the water flow, the outer sleeve 6 and the inner sleeve 7 are not easily worn by the mud and sand.

[0025] In addition, see Appendix Figure 3-4 As shown, the outer sleeve 6 has a first sealing surface 61, and the inner sleeve 7 has a second sealing surface 71 that cooperates with the first sealing surface 61. Both the first sealing surface 61 and the second sealing surface 71 are conical surfaces. Even if mud and water enter between the first sealing surface 61 and the second sealing surface 71, the second sealing surface 71 drives the mud and water to rotate together in a circle. Under the action of centrifugal force, mud with a larger specific gravity is easier to be thrown out than water, and only water without mud passes through the first sealing surface 61 and the second sealing surface 71. The sealing of the multiple oil seals 5 can effectively prevent mud and water from entering the gear box. In addition, since the water reaching the oil seal 5 does not contain mud, it can effectively slow down the wear of the oil seal 5, thereby extending the service life of the oil seal 5.

[0026] In this embodiment, the inner sleeve 7 further includes a sheet-shaped abutment portion 72 extending obliquely outward, and the second sealing surface 71 is located outside the abutment portion 72. The inner sleeve 7 further includes a guide portion 73 extending outward perpendicular to the axial direction of the propeller shaft 1, and the outer sleeve 6 is provided with a guide groove 62 that cooperates with the guide portion 73, and the angle between the abutment portion 72 and the guide portion 73 is an acute angle.

[0027] The sheet-shaped abutment portion 72 can provide a certain elastic force when the first sealing surface 61 and the second sealing surface 71 abut against each other, so that the first sealing surface 61 and the second sealing surface 71 fit more closely. The cooperation of the guide portion 73 and the guide groove 62 can ensure that the first sealing surface 61 and the second sealing surface 71 will not separate from each other during the rotation of the propeller shaft 1. Even if the propeller shaft 1 is slightly displaced relative to the first sealing portion 3, the cooperation of the guide portion 73 and the guide groove 62 can make the outer sleeve 6 move slightly along with the inner sleeve 7, or the outer sleeve 6 made of polytetrafluoroethylene material can be deformed to offset the influence of this part of the displacement on the first sealing surface 61 and the second sealing surface 71.

[0028] In addition, in this embodiment, the outer sleeve 6 is arranged near the outer end of the first sealing portion 3, and an annular cover 8 for fixing the outer sleeve 6 is arranged on the first sealing portion 3, and the cover 8 is detachably connected to the first sealing portion 3 by bolts. The cover 8 can prevent the outer sleeve 6 from being separated from the first sealing portion 3.

[0029] In order to prevent muddy water from entering through the gap between the outer sleeve 6 and the first sealing part 3, and the gap between the inner sleeve 7 and the second sealing part 4, a first sealing ring 63 is arranged between the outer sleeve 6 and the first sealing part 3, the inner sleeve 7 and the second sealing part 4 are interference fit, and a second sealing ring 74 is arranged between the inner sleeve 7 and the second sealing part 4.

[0030] Compared with the prior art, this embodiment has the following advantages:

[0031] Since the present embodiment adopts a conical surface as a sealing surface, the first sealing surface 61 and the second sealing surface 71 can block most of the mud and sand from entering. When a small amount of mud and sand enters the gap between the first sealing surface 61 and the second sealing surface 71, since the second sealing surface 71 rotates with the propeller shaft 1, the second sealing surface 71 drives the mud and sand between the first sealing surface 61 and the second sealing surface 71 to rotate together in a circle. Under the action of centrifugal force, the mud and sand with a heavier specific gravity are easier to be thrown out of the gap than water, so that the cooperation of the outer sleeve 6 and the inner sleeve 7 can block most of the mud and sand from entering, and then the subsequent oil seal 5 blocks water from entering the gear box to complete the sealing. After not being affected by mud and sand, the service life of the oil seal 5 can be greatly extended. Therefore, the present embodiment can have a more stable seal and a longer service life.

[0032] The above embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with the technology to understand the content of the present invention and implement it accordingly, and they cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be included in the protection scope of the present invention.

Claims

1. A marine anti-sand sealing assembly, comprising an annular first sealing portion fixedly connected to a gearbox, an annular second sealing portion arranged on the outer periphery of a propeller shaft, and at least one oil seal arranged between the first sealing portion and the second sealing portion; Features: It also includes an outer sleeve portion arranged on the first sealing portion and an inner sleeve portion arranged on the second sealing portion, the inner sleeve portion is a stainless steel part, the outer sleeve portion is a polytetrafluoroethylene part, the outer sleeve portion has a first sealing surface, the inner sleeve portion has a second sealing surface that cooperates with the first sealing surface, and the first sealing surface and the second sealing surface are both conical surfaces; The inner sleeve also includes a resistance portion extending outwardly in a sheet-like shape and tilted, and the second sealing surface is located on the outside of the resistance portion; the inner sleeve also includes a guide portion extending outwardly perpendicular to the axial direction of the propeller shaft, and the outer sleeve is provided with a guide groove that cooperates with the guide portion; the angle between the resistance portion and the guide portion is an acute angle.

2. A marine anti-sand sealing assembly according to claim 1, characterized in that: The outer sleeve is arranged close to the outer end of the first sealing portion, and the first sealing portion is provided with an annular sealing cover for fixing the outer sleeve.

3. A marine anti-sand sealing assembly according to claim 2, characterized in that: The sealing cover is detachably connected to the first sealing portion via bolts.

4. A marine anti-sand sealing assembly according to claim 1, characterized in that: A first sealing ring is arranged between the outer sleeve and the first sealing portion.

5. A marine anti-sand sealing assembly according to claim 1, characterized in that: The inner sleeve part and the second sealing part are interference fit, and a second sealing ring is arranged between the inner sleeve part and the second sealing part.

6. A gear box, characterized in that: The invention comprises a marine anti-sand sealing assembly as claimed in any one of claims 1 to 5.

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