JPS58183381A - Method of sealing joint - Google Patents

Abstract

PURPOSE:To allow a joint to be worn in conformity with erosion of copper plates so that sealing of the joint would not increase the resistance in water, by filling a joint of outer copper plates with an organotin copolymer that may be modified with rubber. CONSTITUTION:Copper plates 1 are stuck to a steel plate 4 of a hull or the like through an insulating layer 3, so that the outer part of the hull is prevented from being stained. The joint part 2' of the copper plates is filled with an organotin copolymer, that is, tributyl tin methacrylate or triphenyl tin methacrylate copolymer, which may be modified with rubber. In conformity with the erosion of the copper plates, the joint part 2' is worn, so that the joint part would not project and the resistance in water would not increase.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for sealing the joints of external copper plates of ships, marine structures, etc. that are in contact with seawater.

Conventionally, as a measure to prevent contamination of the parts of the hull that come into contact with seawater, as shown in Figure 1 (top view) and Figure 2 (cross-sectional view),
It is known to adhere a rectangular copper plate 1 to a steel plate 4 of the ship's hull itself via an insulating layer 5. In addition, 2 in Figures 1 and 2
is a joint between the copper plates 1, and an organic elastic sealant is usually used.

The copper plate 1 of the hull outer plate sailing in the state shown in Fig. 1.2 is
Since it is electrochemically insulated from the steel plate 4 by the insulating layer 3, only the copper 1 is depleted by natural corrosion in seawater.
1. The thickness becomes as shown by 1' in Figure 3. On the other hand, since joint 2 is an organic elastic sealant, its thickness does not deteriorate due to corrosion, and as shown in Figure 3, joint 2 becomes a protrusion over many years3, and as a result, when sailing, Underwater resistance increases, and the original effect of reducing resistance by preventing fouling is inhibited.

The present invention provides a joint sealing method in which the joint is worn down in accordance with the corrosion wear and tear of the copper plate and does not increase underwater resistance.

In other words, the present invention uses a material that can be used as a joint material, which wears out at almost the same rate as the copper plate corrodes, has toxicity that is repelled by marine life, and is flexible enough to moderate expansion and contraction due to temperature changes of the copper plate. Regarding the method of sealing joints using It is characterized by the use of

The method of the present invention can be applied to ships, marine structures, etc.

Hereinafter, the method of the present invention will be explained using an example in which the method of the present invention is applied to a hull shell plate shown in FIG. 1.2.

In Figures 1 and 2, there are no particular restrictions on the shape of the copper plate 1;
``It may be strip-shaped, square, or any other type, but there is a limit to the joint width. In other words, if the joint width is extremely narrow, it will be difficult to seal the joint material, and if it is too wide, it will be easily damaged by the impact of driftwood, etc., so it is usually about 1 to 10 I.
The depth of the cut joint 2, which is referred to as IIIfi, is determined based on the service life of the copper plate 1 assuming natural corrosion and wear and tear in seawater.

The joint material filled in this joint 2 is made of a copolymer of tributyltin methacrylate or triphenyltin methacrylate (hereinafter abbreviated as organo-metallic copolymer - L-OMP), which is an organotin-based copolymer. Alone or manufactured by Banga Rayon Co., Ltd., product name Dianal) a
J*-197o) can be used.

Fill this joint material to the same height as copper plate 1 1, joint 2
The material OMP is self-poly/puffer (
natural corrosion loss (o,
o1~0. '05 mm 7 years) is equivalent to OMP wear. This situation is shown in Figure 4. In addition, OMP is hydrolyzed in seawater at p) (around 8) and is eluted as chin hydroxide, which is an extremely effective poison for antifouling.The minimum elution rate effective for antifouling is 1. ~2μf
7cm2/day, but the OM used here
P satisfies this range. Furthermore, OMP is flexible at room temperature and is effective in alleviating thermal stress.

Example 150 X 70 A test piece was filled with Dianal MR1970 (manufactured by Rayon Co., Ltd.) (rubber-modified OMP) with a spatula applied twice, and a joint bending test was performed on the test piece (2° A 90° bending test by applying a rod), a room-temperature seawater immersion test (immersion for 6 months), and a seawater rotation ship test (diameter 1ff+, circumferential speed 16 knots) were carried out.

The results were as shown in the table below.

In addition, since both OMP and rubber-modified OMP can be completed with two coats with a spatula, it can be said that the sealability is good.

[Brief explanation of drawings]

Figure 1 is a diagram (top view) to explain the normal hull skin.
, Fig. 2 is a cross-sectional view thereof, Fig. 3 is a diagram for explaining the state of a conventional hull shell plate after many years of use, and Fig. 4 is a diagram showing the state of a hull shell plate to which the method of the present invention has been applied after many years of use. This is a diagram to explain the state of 1゜Responsible agent 1) Resurgent agent Ryo Hagiwara - Figure 3, Figure 4 '+
f'l Agency 1ζ Shin ° Kazuo Wakasugi 1, ° 1 Tsukasa' 1) I/, Elementary 11B Japanese Patent Application No. 66226 2, 4h 'Jl' , , h and 14: V , , ,
,,7-7,Kaθ2:3, ? 1M 41 Name “1 out of 1 Hinno-related patent issuer llIn person 11 ゛l
45-1-11, Marunouchi 2-ro, Nanadai 111-ku, Tokyo amended as shown in the attached sheet.

Claims (1)

[Claims] A method for sealing the joints of external copper plates of ships, marine structures, etc., characterized in that the joints are filled with an organic tin-based copolymer or a rubber-modified organic tin-based copolymer. -Sill method