JPH04136283A - Rustproof cable - Google Patents

Abstract

PURPOSE:To obtain a rustproof cable eliminating a rust factor in oxygen or moisture from gaps between steel wires by sealing cables made of bound steel wires and an oxygen scavenger co-provided to said cable by covering with a covering material. CONSTITUTION:Many zinc-plated steel wires having 5-7mm diameter are bound to form a cable 14 and an oxygen scavenger 8 received in an air-diffusible bag material 10 is provided on the outer periphery of said cable 14, then the outer periphery of said cable 14 is wound by a tape 7 to form a circular cross section, and a covering material 6 made of a thermoplastic resin such as a polyethylene resin, etc., is provided on the most outer layer to afford the objective cable. Besides, an oxygen scavenger of a self-reaction type [e.g. composed of 50wt.% iron powder, 35wt.% zeolite, 5wt.% activated charcoal, 1.5wt.% cable salt, 0.5wt.% caustic soda, 0.05wt.% potassium sorbate and 8wt.% water] or a water-reaction type (e.g. composed of >=99wt.% iron powder and <=1wt.% table salt) is used as the oxygen scavenger.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a rust-proof cable used for cables such as cable-stayed bridges and suspension bridges, and for mooring marine facilities.

[Conventional technology]

Conventionally, cables used for suspending cable-stayed bridges and suspension bridges, and for mooring marine facilities, etc., have been made by bundling steel wires arranged in parallel or twisted at loose pitches. . These cables are used in the atmosphere, on the sea, or under the sea, and are important structural members, so they are required to be completely rust-proof.

Conventionally, as a countermeasure against this problem, rust-proof cables have been used, in which a large number of galvanized steel wires are bundled in parallel or twisted together, and a rust-proof layer made of resin such as polyethylene resin is extruded over the entire length of the cable. ing.

This anti-rust cable is made by first applying rust prevention to the steel wire by galvanizing it, and then using a rust preventive layer made of resin to isolate the cable from the corrosive environment outside.

[Problem to be solved by the invention]

In the case of the above-mentioned conventional rust-proof cable, since the outer sheath made of bundled steel wires is simply coated with a rust-proof layer made of resin, air containing moisture exists in the gaps between the steel wires, and the outside Due to changes in temperature, moisture in the air may condense on the surface of the steel wire, causing rust on the steel wire. As is well known, rust occurs when both moisture and oxygen are present, and if either one is missing, rust will not occur.

SUMMARY OF THE INVENTION An object of the present invention is to provide a rust-proof cable that can advantageously solve the above-mentioned problems.

[Means to solve the problem]

In order to achieve the above object, the rust-proof cable of the present invention includes a cable 14 formed by bundling a large number of steel wires l.
, an oxygen absorber 8 housed in a bag material 10 having air permeability, and a covering material 6 that seals and covers the cable 14 and the oxygen absorber 8 attached thereto.

〔Example〕

Next, the present invention will be explained in detail using illustrated examples.

1 and 2 show an embodiment of the present invention, in which a cable 14 is constructed by bundling a predetermined number of galvanized steel wires with a diameter of 5 to 7 mm, and on the outer periphery of the cable 14,
An oxygen absorber 8 housed in a breathable bag material 10 is placed, and a tape 7 is wrapped around the outer circumference of the cable 14 in which the oxygen absorber 8 is placed to form a circular cross section, and the outermost layer is made of polyethylene. A sheathing material 6 made of thermoplastic resin such as resin is provided for sealing.

In the case shown in FIG. 1, an oxygen absorber 8 housed in a bag material is placed on a part of the outer periphery of the cable 14, and the surrounding area is covered with a polyethylene resin covering material 6. In the cable shown in FIG. 1, an oxygen absorber 8 housed in a bag material is disposed over the entire outer periphery of the cable 14, and the surrounding area is covered with a polyethylene resin covering material 6.

FIG. 3 shows the structure of the cable terminal part. The terminal of the polyethylene covering material 6 that seals and covers the steel wire 1 and the deoxidizing material 8 is embedded in the epoxy resin 4 at the mouth of the socket 2, and The wires 1 are similarly embedded in epoxy resin 4 to seal the gaps between the steel wires. Furthermore, the cable 14 is connected to the heat shrinkable sleeve 5 at the mouth of the socket 2 and the cast metal 3 inside the socket.
The terminal is completely sealed.

For example, as shown in FIG. 4, the oxygen absorber contained in the bag material 10 used in the present invention may be provided with ventilation holes 11 on the inside, that is, on the side that comes into contact with the cable 14, to provide breathability. A bag material 10 containing an oxygen scavenger made of oxygen-reactive powder 9 is used.

As the bag material 10, a bag material made of polyester film, for example, is used, and ventilation holes 11 of several microns in size are provided therein to allow oxygen to pass through. The oxygen absorber 8 housed in the bag material 10 having such air permeability is used to prevent food oxidation, discoloration, and maintain freshness.

It is commercially available for long-term storage of pharmaceuticals, etc., and for example, Sanso Cut (trade name 2, manufactured by Finetic Co., Ltd.) can be used.

The oxygen scavenger 8 includes a self-reactive type and a water-reactive type. Self-reactive type is a type of oxygen scavenger that contains moisture in its composition, and can start the deoxidizing effect by its own moisture even if there is no moisture caused by condensation inside the cable. It is a drug.

The composition of the self-reactive oxygen scavenger is, for example, 50% iron powder in weight ratio (percentage). Zeolite 35. Activated carbon 59 salt 1
．． 5. Caustic soda 0.5. Potassium sorbate 0.0
5. Water is 8.

On the other hand, the moisture-reactive type is a type that reacts only when there is moisture generated due to dew condensation inside the cable, and the composition of the moisture-reactive oxygen scavenger is, for example, iron powder in weight ratio 99 or more.

The salt content is 1 or less. When carrying out the present invention, either a self-reactive type or a moisture-reactive type deoxidizing material may be used.

In addition, in order to reduce the deoxidation reaction during operation, it is preferable to delay the deoxidation reaction time after the bag material 10 containing the oxygen absorber 8 used in the present invention is opened and ready for use. It is better to make the ventilation holes 11 of the bag material 10 as small as possible or to reduce the number of ventilation holes 11.

The amount of oxygen scavenger 8 provided is determined by the void volume of cable 14. Generally, the oxygen concentration in the air is about 21%, so in principle, all the voids in the cable should be regarded as air, and the amount that has an oxygen absorption capacity of 21% of this volume should be installed as a predetermined amount. . However, in practical terms, the amount of oxygen scavenger placed may be adjusted because there is an oxygen scavenging reaction during the working time and the antirust effect can be achieved even if all oxygen is not absorbed.

FIG. 5 and FIG. 6 are experimental examples of the rust-proof cable of the present invention.

In this experimental example, a predetermined amount of oxygen absorber 8 housed in a bag material is placed on a cable 14 with a length of 500 mm, which is made by bundling 85 steel wires 1 with a diameter of 7 mm, and a tape-shaped covering material 6 is placed around the cable 14.
The device was sealed with a sealing material 12, and the oxygen removal effect was measured using an oxygen thermometer 13 placed at the terminal. According to this experiment, the oxygen concentration, which was initially 21%, decreased to 6% after 8 hours, to 4% or less after 24 hours, and after that, stable results were obtained at 3% over a long period of time.

In the present invention, when disposing the oxygen absorber 8 housed in the bag material on the cable 14, the initial deoxidizing reaction after opening is fast, as seen in the experimental results, so the cable 14 must be sealed immediately during construction. Covering is necessary. As a means of achieving this, it is effective to temporarily cover the area with taping before completely covering it. Further, as described above, the bag material 10 that delays the initial deoxidation reaction is used, and the cable 14 in the bag material 10 is
It is preferable to provide ventilation holes 11 only on one side.

〔Effect of the invention〕

According to the present invention, the oxygen absorber 8 housed in the air-permeable bag material 1o is disposed in the cable 14, which is formed by bundling a large number of steel wires 1, and the oxygen absorber-equipped cable is Since the surrounding area is hermetically covered with a covering material 6 to isolate it from the outside air, oxygen can be absorbed into the oxygen scavenger 8 from the gaps between the steel wires 1 in the cable 14, thereby preventing the steel wires 1 from corroding. You can remove the factors that cause
The effect of significantly increasing the rust prevention effect of the cable 14 can be obtained.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing a first example of the rust-proof cable of the present invention, and FIG. 2 is a cross-sectional view showing a second example of the rust-proof cable of the present invention. Figure 3 is a partially cutaway longitudinal side view showing the structure near the cable end where the steel wire and oxygen scavenger are arranged in parallel;
FIG. 4 is a cross-sectional view showing a state in which an oxygen absorber is housed in a bag material having air permeability. FIG. 5 is a partially cutaway vertical side view for explaining an experimental example of a rust-proof cable, and FIG. 6 is a chart showing the relationship between oxygen concentration and elapsed time determined by the experiment. In the figure, ■ is steel wire, 2 is socket, 3 is cast metal, 4 is epoxy resin, 5 is heat-shrinkable sleeve, 6 is coating material, 7 is tape, 8 is oxygen absorber, 9 is oxygen reactive powder, 1
0 is a bag material, 11 is a ventilation hole, and 14 is a cable.

Claims (1)

[Claims] A cable 14 formed by bundling a large number of steel wires 1, an oxygen absorber 8 housed in a bag material 10 having air permeability, and the cable 14 and the oxygen absorber 8 attached thereto are hermetically coated. A rust-proof cable consisting of a covering material 6.