JPH0156032B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a method for modifying the stern of a hull that can minimize the range of hull modifications necessary to position the propeller on the hull centerline, such as when converting a two-shaft ship to a single-shaft ship. Regarding the method.

Conventionally, when converting a two-shaft ship to a single-shaft ship, in order to remove the old propeller and place a new propeller on the hull centerline, as shown in Figures 1 and 2, the old propeller must be placed directly above the new propeller 1. A new stern shell plate portion in which the stern shell plate portion 2 (shown with hatching) is cut and removed to ensure a predetermined propeller aperture a, and the outer surface of the removed portion is formed into a curved shape. 3 (shown using a two-dot chain line), as well as this new stern shell section 3 and side shell panel 4.
In order to connect and shape the outer surface with a smooth curved surface, the intersection of the above-mentioned portion 3 and the side shell plate 4, that is, the old ship side shell plate portion 6 below cut position 5 (shown by hatching in Fig. 1) is cut. , was removed and a new outer panel was installed in this area. In the figure, 1a is the new propeller surface, 7a is the old propeller surface, 8 is the stern, 9 is the rudder, b is the baseline, c is the center of the hull, d is the stern perpendicular, and e is the new propeller axis. .

However, according to this method, the new stern skin part 3
Since it is constructed into a curved structure, the material cost of this part,
Not only are processing costs and installation costs high, but the remodeling area of the old ship side shell section 6 becomes large, so there is a drawback that remodeling this section also requires a large amount of materials and labor.

The present invention was made in order to eliminate the above-mentioned drawbacks, and the stern shell plate above the propeller is cut and removed, and the stern shell plate after removal is made into a substantially flat plate shape and the required propeller aperture is secured. This relates to a method for modifying the stern of a ship, in which a flat plate member is attached to the flat plate-shaped portion described above, and since the stern shell plate directly above the new propeller is formed into a flat plate, this part cannot be modified. It is inexpensive and the scope of shaping of the hull side panel can be reduced.
This part also has the advantage of being inexpensive to modify.

Embodiments of the present invention will be described below with reference to the drawings. 3 and 4 show an embodiment of the present invention, in which the old stern outer plate portion 22 (shown with hatching) directly above the new propeller 1 is shaped into a substantially flat plate and the required propeller aperture a A flat plate 23 is attached to the removed portion so as to ensure the following, and a reinforcing member (not shown) is placed inside this flat plate 23 to form a new stern outer plate portion 24 directly above the new propeller 1. In addition, the old ship's side shell plate part 26 (shown by hatching in FIG. 3) below the cut position 25 where the outer edge of this flat plate 23 intersects with the ship's side shell plate 4 is cut and removed as shown in the figure. Attach a new outer panel to the damaged area and reshape it.

It should be noted that, in order to avoid duplication of explanation, the symbols used in explaining the conventional modification method are used for the symbols of various parts of the hull other than those mentioned above.

Comparing the modification method of the present invention with the conventional modification method, when using this method, the removed part directly above the new propeller is smaller (see hatched part 22 in Figure 4 and hatched part 2 in Figure 2), and Since the hull section after removal was constructed with a simple flat plate structure, the amount of remodeling work such as removal work and materials, processing, and installation of newly installed parts can be reduced.In addition, the shaping work of the ship's side skin can also be cut using this method. Since the position 25 is lower than the cut position 5 according to the conventional method, the range of removal work due to the characteristics of the hull diagram, and therefore the range of new construction work on the outer skin, is also smaller (hatched part 26 in Figure 3 and cut position 5 in Figure 1). (See hatched part 6), the amount of modification work for this part can be greatly reduced, and the construction period can also be shortened.

In addition, the ship shape modified by this method is not inferior to the conventional ship shape in terms of propulsion performance, stability performance, etc.

Furthermore, this method can be used not only when converting a two-shaft ship into a single-shaft ship, but also when converting an old propeller in a single-shaft ship, for example.
It can be applied to many other types of modification work, such as when replacing a new propeller with a larger diameter.

Note that the present invention is not limited to the above-described embodiments; for example, the flat plate 23 has a cross section in the hull width direction forming a horizontal line (see FIG. 4), but has some primary curvature in the hull longitudinal direction. It goes without saying that various changes may be made without departing from the gist of the present invention, such as that the present invention may be modified to a different shape.

In the method for remodeling the stern of a hull according to the present invention, the old stern outer plate directly above the propeller is cut and removed so as to secure the required propeller aperture, and the removed part is formed into a flat plate shape. The amount of modification work can be reduced compared to the above method, and the scope of modification work on the ship's side shell below the cut position can also be reduced. It has excellent effects such as being able to shorten the time.

[Brief explanation of drawings]

Figures 1 and 2 show the conventional modification method;
Figure 1 is a partial side view of the ship, Figure 2 is a view from the - direction in Figure 1, Figures 3 and 4.
The figures show an embodiment of the present invention, FIG. 3 is a partial side view of a ship, and FIG. 4 is a view taken from the - direction in FIG. 3. In the figure, reference numeral 1 indicates the new propeller, 22 indicates the old stern outer plate, 23 indicates the flat plate, and a indicates the propeller aperture.

Claims (1)

[Claims] 1. Cut and remove the stern outer plate above the propeller, form the removed stern outer plate into a substantially flat plate shape and secure the required propeller aperture, and attach a flat plate to the flat plate-shaped portion. Attach the flat member, cut and remove the lower ship side skin from the cut position where the outer edge of the flat member intersects with the ship's side skin, and connect the removed portion to the outer edge of the flat member and the cut portion of the ship's side skin. A method for modifying the stern of a ship, which is characterized by installing a new outer panel.