Anti-fishing net stern tube protection system
By installing an anti-fishing net stern tube protection system on the stern propeller of the ship to collect and isolate the fishing net debris, the problem of seal leakage and wear caused by fishing net debris entering the seal gap is solved, and the stable operation and economical maintenance of the sealing system are achieved.
Patent Information
- Application Number
- CN202422240642.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-12
- Publication Date
- 2025-06-27
- Estimated Expiration
- 2034-09-12
AI Technical Summary
The stern propeller of the ship wraps around the fishing net during rotation, causing the net debris to enter the gap between the sealing bushing and the stern seal, destroying the oil/water film lubrication, resulting in seal leakage and seal ring wear.
A fishing net anti-fishing stern tube protection system is designed, including a protective cover and a stern tube fishing net collection device. The fishing net is cut through the fishing net cutting knife and the debris is collected into the stern tube fishing net collection device to prevent debris from entering the sealing gap.
Effectively isolate fishing net debris, reduce the risk of seal failure, reduce seal ring wear, extend service life, and avoid environmental pollution.
Smart Images
Figure CN223031245U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of ship protection, in particular to an anti-fishing net stern tube protection system. Background Art
[0002] The propeller hub at the stern of a ship is usually designed with evenly distributed fixed fishing net cutters. There is a gap of 5-10 mm between the fishing net cutter and the rotating propeller hub. During the rotation of the propeller, it will entangle the fishing net. The fishing net rotates together with the propeller and is cut into fragments by the fishing net cutter. Most of the fragments are carried away by the water flow, and at the same time, some fragments will fall into the gap between the sealing bushing and the stern seal from the gap between the tail pipe protection cover and the propeller hub. Since the sealing bushing is fixed on the stern shaft and rotates with the stern shaft, while the stern seal is a non-moving part fixed on the stern pipe, there is a gap between the sealing bushing and the stern seal. During the sealing operation, an effective oil film and water film lubrication will be established between the stern seal ring and the bushing to ensure the good operation condition of the stern seal. The fishing net fragments that fall into the gap between the sealing bushing and the stern seal will enter the sealing ring of the stern seal along with the rotation of the propeller hub, thus destroying the balance of oil pressure / air pressure / water pressure in the sealing ring, resulting in seal leakage, polluting the environment, and even causing the seal ring to be stuck, worn, and burned out, which requires dry-docking and replacement, bringing huge economic losses to the shipowner. Summary of the Utility Model
[0003] To solve the above technical problems, the utility model provides an anti-fishing net stern tube protection system, which physically and mechanically isolates fishing net fragments, avoids fishing net fragments from entering the gap between the sealing bushing and the stern seal, reduces the problem of seal failure caused by foreign objects entering the stern shaft seal ring, ensures the safe and stable operation of the stern seal system, and improves the economy of ship operation and maintenance.
[0004] To achieve the above purposes, the utility model adopts the following technical solutions:
[0005] An anti-fishing net stern tube protection system includes a protection cover and a stern tube fishing net collection device. The protection cover is arranged between the end face of the stern post close to the propeller hub and the propeller hub. A fishing net cutter extending to the outer surface of the propeller hub is installed at one end of the protection cover close to the propeller hub. The stern tube fishing net collection device is located on the front end face of the propeller hub inside the protection cover. The stern tube fishing net collection device is a ring with a groove structure on its outer wall. An underwater detection and measurement hole is provided on the protection cover.
[0006] Furthermore, the stern tube fishing net collecting device includes two semi-circular rings. Each semi-circular ring includes a cylindrical part. At both ends of the outer side wall of the cylindrical part, a first outer retaining ring and a second outer retaining ring are vertically provided along its circumference. The two ends of the first outer retaining ring and the second outer retaining ring are connected by a connecting component. A plurality of screw holes are evenly distributed on the first outer retaining ring, and the first outer retaining ring is fixedly connected to the front end face of the propeller hub through fixing bolts.
[0007] Furthermore, the connecting component includes four connecting plates and connecting bolts. A plurality of screw holes are oppositely provided on both ends of the first outer retaining ring and the second outer retaining ring. A plurality of screw holes are opened on the connecting plates. The connecting plates are lapped at the butt joint of the first outer retaining ring and the second outer retaining ring and are connected to both the first outer retaining ring and the second outer retaining ring through connecting bolts.
[0008] Furthermore, the system further includes a sealing bushing and a stern seal. The longitudinal section of the sealing bushing is L-shaped. Its vertical part is fixed to the propeller hub through bolts. The stern seal is sleeved on the sealing bushing to form a shaft seal for the propeller shaft. The stern seal is installed on the stern tube through bolts.
[0009] Furthermore, a sealing wear measurement hole is opened on the cylindrical part. A sealing wear measurement hole cover plate is provided outside the sealing wear measurement hole. The sealing wear measurement hole cover plate is connected to the cylindrical part through cover plate fixing bolts.
[0010] Furthermore, the longitudinal section of the sealing wear measurement hole cover plate is L-shaped. Its horizontal part covers the sealing wear measurement hole. Screw holes are opened at positions opposite to the screw holes on the first outer retaining ring on its vertical part. Fixing bolts pass through the screw holes on the vertical part.
[0011] Furthermore, the width of the first outer retaining ring is smaller than the width of the second outer retaining ring.
[0012] For the anti-fishing net stern tube protection system of the present utility model, by adding a stern tube fishing net collector on the propeller hub to collect the fishing net debris that falls after being cut by the fishing net cutter, the fishing net debris will slide along the outer surface of the fishing net collector to the bottom of the stern tube seal protection cover and scatter into the surrounding waters through the underwater detection holes at the bottom of the protection cover. Through the present invention, the fishing net is mechanically isolated from entering the sealing ring, greatly reducing the possibility of broken fishing nets entering the stern seal, avoiding the damage of the oil film / water film between the sealing ring and the bushing, reducing the risk of seal failure, reducing the wear of the sealing ring, and extending the service life.
[0013] Compared with the sealing design of conventional ships, this device can optimize and transform the sealing system without affecting the operation of the conventional seal. The semi-fishing net collector adopts a two-half assembled form, which is convenient for installation on newly built ships and modification of operating ships. BRIEF DESCRIPTION OF THE DRAWINGS
[0014] Figure 1 is a schematic structural view of the anti-fishing net stern tube protection system of the present utility model;
[0015] Figure 2 is a side view of the stern tube fishing net collecting device of the present utility model;
[0016] Figure 3 is a front view of the stern tube fishing net collecting device of the present utility model.
[0017] Among them, 1 - propeller hub, 2 - stern shaft, 3 - fishing net cutter, 4 - seal wear measurement instrument, 5 - stern tube fishing net collecting device; 6 - protective cover; 7 - stern seal; 8 - stern tube; 9 - stern post; 10 - cover fixing bolt; 11 - cover plate of seal wear measurement hole; 12 - semi-circular ring; 13 - connecting bolt; 14 - connecting plate; 15 - fixing bolt, 16 - seal bushing, 17 - underwater detection measurement hole, 121 - cylindrical part, 122 - first outer retaining ring, 123 - second outer retaining ring, 1211 - seal wear measurement hole. Detailed implementation manners
[0018] Next, the technical solutions in the embodiments of the present utility model will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present utility model. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without making creative efforts shall fall within the protection scope of the present utility model.
[0019] As Figures 1 - 3 shown, an anti-fishing net stern tube protection system includes a protective cover 6, a seal bushing 16, a stern seal 7 and a stern tube fishing net collecting device 5. The protective cover 6 is arranged between the end face of the stern post 9 close to the propeller hub 1 and the propeller hub 1. A fishing net cutter 3 extending to the outer surface of the propeller hub 1 is installed at one end of the protective cover 6 close to the propeller hub 1. The stern tube fishing net collecting device 5 is located on the front end face of the propeller hub 1 inside the protective cover 6. The stern tube fishing net collecting device 5 is a ring with a groove structure on its outer wall. An underwater detection measurement hole 61 is opened on the protective cover 6; the longitudinal section of the seal bushing 16 is L-shaped, and its vertical part is installed on the propeller hub 1 through bolts. The stern seal 7 is sleeved on the seal bushing 16 to form a propeller shaft seal, and the stern seal 7 is installed on the stern tube 8 through bolts.
[0020] The stern tube fishing net collecting device 5 includes two semi-circular rings 12. The semi-circular ring 12 includes a cylindrical part 121. At both ends of the outer side wall of the cylindrical part 121, a first outer retaining ring 122 and a second outer retaining ring 123 are vertically provided along its circumference. At both ends of the first outer retaining ring 122 and the second outer retaining ring 123, they are connected by a connecting component. A plurality of screw holes are evenly distributed on the first outer retaining ring 122, and the first outer retaining ring 122 is fixedly connected to the front end face of the propeller hub 1 through a fixing bolt 15; A sealing wear measurement hole 1211 is provided on the cylindrical part 121. A sealing wear measurement hole cover plate 11 is provided outside the sealing wear measurement hole 1211. The sealing wear measurement hole cover plate 11 is connected to the cylindrical part 121 through a cover plate fixing bolt 10; The longitudinal section of the sealing wear measurement hole cover plate 11 is L-shaped. Its horizontal part covers the sealing wear measurement hole 1211. A screw hole is provided at a position opposite to the screw hole on the first outer retaining ring 122 on its vertical part. The fixing bolt 15 passes through the screw hole on the vertical part; The width of the first outer retaining ring 122 is smaller than the width of the second outer retaining ring 123.
[0021] The connecting component includes four connecting plates 14 and connecting bolts 13. A plurality of screw holes are oppositely provided on both ends of the first outer retaining ring 122 and the second outer retaining ring 123. A plurality of screw holes are provided on the connecting plate 14. The connecting plate 14 is lapped at the butt joint of the first outer retaining ring 122 and the second outer retaining ring 123 and is connected to both the first outer retaining ring 122 and the second outer retaining ring 123 through the connecting bolt 13.
[0022] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principle and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.
Claims
1. A fishing net stern tube protection system, characterized in that: It includes a protective cover and a stern tube fishing net collecting device. The protective cover is arranged between the end surface of the stern column close to the propeller hub and the propeller hub. A fishing net cutter extending to the outer surface of the propeller hub is installed at the end of the protective cover close to the propeller hub. The stern tube fishing net collecting device is located on the front end surface of the propeller hub inside the protective cover. The stern tube fishing net collecting device is a circular ring with a groove structure on the outer wall, and an underwater detection and measurement hole is opened on the protective cover.
2. The anti-fishing net stern tube protection system according to claim 1, characterized in that: The stern tube fishing net collecting device includes two semicircular rings, each of which includes a cylindrical portion, and a first outer retaining ring and a second outer retaining ring are vertically provided at both ends of the outer side wall of the cylindrical portion along its circumference, and both ends of the first outer retaining ring and the second outer retaining ring are connected by a connecting assembly, and a plurality of screw holes are evenly distributed on the first outer retaining ring, and the first outer retaining ring is fixedly connected to the front end surface of the propeller hub by fixing bolts.
3. The anti-fishing net stern tube protection system according to claim 2, characterized in that: The connecting assembly includes four connecting plates and connecting bolts. A plurality of screw holes are arranged on the two end sides of the first outer retaining ring and the second outer retaining ring. A plurality of screw holes are opened on the connecting plates. The connecting plates are overlapped at the joint of the first outer retaining ring and the second outer retaining ring, and are connected to the first outer retaining ring and the second outer retaining ring at the same time through the connecting bolts.
4. The anti-fishing net stern tube protection system according to claim 2, characterized in that: The system also includes a sealing bushing and a stern seal. The longitudinal section of the sealing bushing is L-shaped, and its vertical portion is installed on the propeller hub through bolts. The stern seal sleeve is mounted on the sealing bushing to form a propeller shaft seal, and the stern seal is installed on the stern tube through bolts.
5. The anti-fishing net stern tube protection system according to claim 4, characterized in that: A seal wear measurement hole is provided on the cylindrical portion, a seal wear measurement hole cover plate is provided on the outer side of the seal wear measurement hole, and the seal wear measurement hole cover plate is connected to the cylindrical portion via a cover plate fixing bolt.
6. The anti-fishing net stern tube protection system according to claim 5, characterized in that: The longitudinal section of the seal wear measurement hole cover plate is L-shaped, its transverse portion covers the seal wear measurement hole, and a screw hole is opened at a position of its vertical portion relative to the screw hole on the first outer retaining ring, and a fixing bolt passes through the screw hole on the vertical portion.
7. The anti-fishing net stern tube protection system according to claim 3, characterized in that: The width of the first outer retaining ring is smaller than the width of the second outer retaining ring.