JPH067040Y2 - Anti-corrosion structure of marine propeller shaft - Google Patents

Description

[Detailed Description of the Invention] 1) Purpose of the Invention (a) Field of Industrial Application The present invention relates to an anticorrosion structure for a propeller shaft for a ship.

(B) Conventional Technology Conventionally, rubber has been wound around the propeller shaft or a FRP (glass fiber reinforced plastic) lining 4 has been provided as a means for preventing corrosion of marine propeller shafts by seawater. A conventional example is shown in FIG. A seawater-lubricated propeller shaft 1 is axially supported by a rubber bearing 11 of a hull 10 via a sleeve 2. The sleeve is shrink-fitted only on the sliding portion of the propeller shaft 1 with the rubber bearing 11. If a sleeve is fitted over the entire peripheral surface of the propeller shaft that comes into contact with seawater, corrosion of the propeller shaft can be prevented, but it is very expensive and is not used for long shafts. For this reason, the portion of the propeller shaft between the sleeves is wrapped with rubber or is FRP-lined as described above.

This rubber winding is a method in which raw rubber is wound around a propeller shaft, a tape is wound over the propeller shaft and fixed, and this is put in a vulcanized sill and processed, but it has the following drawbacks. First, the propeller shaft must be transported to the factory where the vulcanization tyre is installed. Second, since the propeller shaft generally has a large shaft diameter and a large shaft length, a large facility for accommodating the propeller shaft is required. Thirdly, the processing time including the propeller shaft transfer time becomes long.

On the other hand, the FRP lining method is a method of alternately laminating resin and glass fiber on the exposed portion of the propeller shaft, and since the work can be performed in the propeller shaft manufacturing factory, the processing time and cost are greatly reduced.

(C) Problem to be devised The FRP lining method is an anticorrosion method that depends only on the adhesive force between the resin and the metal of the propeller shaft, and the adhesive force is greatly affected by the type of resin and the pretreatment of the metal surface, etc., and the adhesive force is weak. When peeling. There is also a risk of peeling due to the torsional stress of the propeller shaft. Seawater invades from the peeled part,
It may cause corrosion or breakage of the propeller shaft. Therefore, it is somewhat unreliable for long-term corrosion protection of 3 years or more.

Therefore, the object of the present invention is to prevent the entry of seawater regardless of the strength of the FRP and to greatly improve the reliability of the propeller shaft of a ship which can be used for long-term (for example, 4 years or more) corrosion protection. It is to provide an anticorrosion structure.

2) Configuration of the Invention (a) Means for Solving the Problem In the invention, a seal ring having a lip portion presses the lip portion against an end surface of a sleeve fitted to a sliding portion of a propeller shaft, and With the inner peripheral surface of the seal ring in pressure contact with the outer peripheral surface of the propeller shaft, the seal ring is fitted onto the propeller shaft, and F
It is characterized in that the RP lining is applied to the propeller shaft so as to cover the pressure contact portion between the lip portion and the end surface of the sleeve.

(B) Action In the present invention, the seal ring is fitted to the propeller shaft with its lip portion pressed against the end surface of the sleeve and the inner peripheral surface of the seal ring pressed against the outer peripheral surface of the propeller shaft. There is. Therefore, the adhesive force between the sleeve and the FRP lining is weak, so that even if seawater enters from between them, the seawater does not reach the propeller shaft.

(C) Example Hereinafter, the example shown in FIGS. 1 and 2 will be described. In these embodiments, the seal ring 3 having a lip portion 8 and made of a rubber-like elastic body is used to replace the lip portion 8 with the propeller shaft 1.
It is fitted to the propeller shaft 1 in a state where it is pressed against the end surface of the sleeve 2 fitted in and the inner peripheral surface of the seal ring 3 is pressed against the outer peripheral surface of the propeller shaft 1. The seal ring 3 is securely fixed to the propeller shaft 1 by winding a wire made of, for example, a copper wire 5 around the seal ring 3. The seal ring 3 is attached to the shaft in one piece and then bonded to form a continuous ring. However, an endless annular body may be used if it can be mounted. After the seal ring 3 is fitted on the propeller shaft 1 as described above, the FRP lining 4 is applied from above. That is, the resin is first applied, and the glass fiber is wound on the resin. Repeat this work. The FRP shrinks when it hardens after the lining work. Therefore, due to the contraction, the FRP lining 4 and the seal ring 3 are in better contact with each other.
Further, the contraction improves the adhesion between the seal ring 3 and the propeller shaft 1 and between the lip portion 8 and the sleeve 2. In the embodiment shown in FIG. 2, of the seal ring 3,
Concavities and convexities 6 are provided in the portion that comes into contact with the propeller shaft 1 to enhance the hermeticity.

According to the configuration of the embodiment shown in FIGS. 1 and 2, seawater is discharged from the boundary between the FRP lining 4 and the sleeve 2, that is, the boundary between the FRP lining 4 and the sleeve 2 at the upper right of FIGS. , The seawater does not reach the propeller shaft 1 because the lip portion 8 exists. That is, the seal ring 3 is tightened with the copper wire 5, and the FRP lining 4 is applied so as to cover it, so that the propeller shaft 1
Is sufficiently pressed against, and therefore the lip 8
Even in the absence of the above, it is possible to prevent corrosion of the propeller shaft 1 due to seawater passing between the seal ring 3 and the end surface of the sleeve 2 and entering between the seal ring 3 and the propeller shaft 1. However, if the lip portion 8 does not exist, seawater that has passed between the seal ring 3 and the end surface of the sleeve 2 will not flow when the sleeve 2 and the propeller shaft 1 are not fitted together sufficiently. It is not possible to prevent corrosion of the propeller shaft 1 due to penetration between the propeller shaft 1 and the propeller shaft 1. If the structure in which the lip portion 8 is pressed against the end surface of the sleeve 2 is adopted as in the embodiment shown in FIGS. 1 and 2, corrosion of the propeller shaft 1 due to intrusion of seawater between the sleeve 2 and the propeller shaft 1. Can also be prevented, and as a result, the anticorrosion effect is significantly improved.

3) Effect of the device Only by adding the seal ring 3 to the conventional FRP lining technology, a high sealing effect can be obtained regardless of the adhesive force between the FRP lining and the metal sleeve, and seawater can be prevented from entering by the seal ring. Since it is prevented and does not reach the propeller shaft, the anticorrosion property is improved, and the anticorrosion structure is sufficiently resistant to long-term use of 3 years or 4 years or more. For this reason, conventionally, the lining must be replaced every 1 year or 2 years, but it can be used for 4 years or more, which greatly contributes to the reduction of the lining cost.

[Brief description of drawings]

1 and 2 are schematic sectional views of an embodiment of the present invention, and FIG.
The figure is a cross-sectional view of a conventional anticorrosion structure. 1 ... propeller shaft, 2 ... sleeve, 3 ... seal ring, 4 ... FRP lining, 5 ... copper wire, 6 ... unevenness, 8 ... lip part.

Claims (1)

[Scope of utility model registration request] 1. A ship propeller shaft (1) for corrosion protection of a shaft (1)
In an anticorrosive structure for a propeller shaft for a ship, which has a structure provided with an RP lining (4), a seal ring (3) having a lip portion (8) has a propeller shaft (1) for the lip portion (8).
Of the propeller shaft (1) in a state where the end face of the sleeve (2) fitted to the sliding part of the propeller shaft (1) and the inner peripheral surface of the seal ring (3) are pressed against the outer peripheral surface of the propeller shaft (1).
The FRP lining (4) is applied to the propeller shaft (1) so as to cover the pressure contact portion between the lip portion (8) and the end surface of the sleeve (2). Characteristic anti-corrosion structure for propeller shafts for ships.