JPS6286606A - Strand for cable conductor and conductor for power cable - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a conductor wire and a power cable conductor.

(Prior Art) (Problems to be Solved by the Invention) Copper or aluminum has traditionally been used as a conductor for power cables, but they undergo thermal expansion and contraction due to temperature changes associated with load current and seasonal changes. As a result, the cable may become undulated or tension may be applied to the connection point, which may cause various cable failures. Therefore, in order to absorb the above-mentioned thermal expansion and contraction, it is necessary to perform so-called snake installation in which the cable meanderes in advance, or to provide offsets, etc., and measures against thermal behavior are extremely important. There is a problem in that the cost required for countermeasures accounts for a large proportion of the track construction cost. Further, there is a problem that if there is a large amount of curlen, it becomes difficult to draw the wire as a wire.

(Means for Solving the Problems) The present invention has been made to solve the above problems, and in order to increase the strength of various metals, various fibers are interposed in a metal matrix. Fiber-reinforced composite metal materials (abbreviated as FRM)
Carbon fiber has been carefully researched for various purposes, but it has been focused on the fact that carbon fiber has a negative coefficient of linear expansion, and it has been used as a base metal for power cables. Rough wire made of carbon fiber-reinforced composite alloy with carbon fiber volume content of 5 to 30% (up to about 50% in volume resistivity) made of copper or aluminum as the reinforcing fiber is cut to the required size. The drawn wire is used as a conductor for power cables.

(Function) The isolateral linear expansion coefficient α' of the carbon fiber reinforced alloy as described above is expressed by the following equation.

Here, α is the coefficient of linear expansion, %A is the volumetric content in the alloy, E is the elastic modulus, and 5uffix i is the base metal (copper or aluminum) for 1 m of carbon fiber.

In the above equation, αi is negative, so α′<6m.

That is, by reinforcing with carbon fiber, the linear expansion coefficient of the alloy becomes smaller than that of the base metal, and n
becomes smaller and smaller as the carbon fiber content increases. Although it is preferable for a conductor for a power cable to have a smaller linear expansion coefficient, the reason why the carbon fiber content is limited as described above in the present invention will be explained. Since carbon fibers have a lower electrical conductivity than the base metal, the equivalent conductivity of the carbon fiber reinforced alloy will be worse than the conductivity of the base metal.

Therefore, if the content of carbon fiber is small, the coefficient of linear expansion will be too thick, and if the content is too thick, the conductivity will decrease, so the content tt
This is a range that is determined to be optimal.

Short carbon fibers with an outer diameter of 5 to 10 μm are used as reinforced fibers, the content of the fibers is 5 to 30%, fibers are produced in the longitudinal direction as in Example 2, copper is used as the base metal, and reinforcing fibers with an outer diameter of 5 to 10 μm are used.
Using lOμ long carbon fibers, the fiber content is 5 to 30%.
A carbon fiber reinforced steel wire was manufactured by passing a long carbon fiber thread through molten steel.

For the above examples, the linear expansion coefficient, volume resistivity, and tensile strength were estimated and the results are shown in the following table.

Next, the calculated values of linear expansion coefficient and volume resistivity are shown in the figure when the base metal is copper or aluminum and the content ratio of carbon fiber is varied. In Figures 1 to 3, the optimum value of the carbon fiber content ratio is determined as described above in the present invention from values that reduce the linear expansion coefficient by at most 50% and increase the volume resistivity by 50% or less. .

(Effects of the Invention) According to the present invention, the coefficient of linear expansion as a conductor is considerably reduced, and when used in an f'L'i electric cable, thermal expansion and contraction due to temperature changes is reduced. Since undulations and tension at connections are reduced, the need for thermal behavior measures such as snake installation and off-series installation during cable installation is reduced, which is expected to result in reductions in track construction costs.
Ru.

[Brief explanation of drawings]

Figure 1 is a graph showing the relationship between carbon fiber content and linear expansion coefficient in the conductor of the present invention, Figure 2 is a graph showing the relationship between carbon fiber content and volume resistivity, and Figure 3 is a graph showing the relationship between carbon fiber content and volume resistivity. It is a graph showing the relationship between tensile strength. Agent Patent Attorney Mamoru Takeuchi 1st Zu and Jumura #1 Goukukushi (ni) - Charcoal (Original Rei π hand (%) - 3rd Ward Izumi 1** Shahat 1z) -

Claims (2)

[Claims] (1) Copper or aluminum is reinforced with carbon fiber having a negative coefficient of linear expansion, and the volume content of the carbon fiber is 5 to 30%.
A wire for a cable conductor characterized by being made of a carbon fiber composite metal material. (2) Copper or aluminum is reinforced with carbon fiber having a negative coefficient of linear expansion, and the volume content of the carbon fiber is 5 to 30%.
A conductor for a power cable, characterized by being made of a carbon fiber reinforced composite metal material.