JPH0246612A - Manufacture of reinforced plastic armored cable - Google Patents

Abstract

PURPOSE:To prevent the generation of cracks by a stress and resulting in a cutting off of the wire by heating a linear body at a hardenable temperature to promote to harden to almost a perfect hardening, and after that, winding the periphery of an elastic cable with the linear body up to a perfect hardening. CONSTITUTION:A reinforced plastic linear body 51 is conveyed through a preheating zone 14 to a heating zone 15 of a heating device 13, where it is heated by raising the temperature up to a hardening temperature, and the hardening is promoted near to a perfect hardening. The linear body 5 is advanced further, and stranded around an elastic cable 1 which has run through the center of a stranding device 10, at the position of a stranding mouth piece 18. The linear body 51 stranded to the periphery of the cable 1 after passing through the stranding mouth piece 18 is released from the ambiance of the hardenable temperature, and the hardening is promoted to make into a perfectly hardened reinforced plastic linear body 5. As a result, a reinforced plastic wire armored cable which has no fear of generating cracks resulting from the residual stress (bending deformation) can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method of providing an electrical cable with a reinforced plastic wire sheath as a high tensile strength body and as protection from external forces.

[Background Art] Various marine equipment such as underwater observation equipment and submarine working machines in marine development projects are connected to support equipment on land or at sea via electric cables in order to supply power to them and transmit and receive signals. In addition to the above-mentioned purposes, electrical cables are also used for the suspension and lifting of marine equipment, for which this type of electrical cable is used as a tensile strength body for suspension and lifting, as well as for mechanical protection from external forces. It is equipped with wire armor that serves as a.

Conventionally, steel wires have generally been used as the above-mentioned cable armor, but when it comes to long cables for deep sea use, the weight of the steel wires in the armor becomes a burden, making it difficult to handle the cables and marine equipment. Because of this problem, recently, wire braces made of reinforced plastic wires with low specific gravity have been used.

However, methods for applying reinforced plastic wire sheathing to the outer periphery of an electric cable include wrapping a pre-hardened reinforced plastic wire around the outer periphery of the electric cable, or when the reinforced plastic wire is relatively thick. A method is known in which a reinforced plastic filament with uncured or semi-cured impregnated resin is wound around the outer periphery of an electric cable and then heated and cured.

[Problems to be Solved by the Invention] In the former method described above, in which a pre-hardened reinforced plastic filament is wound around the outer periphery of an electric cable, when the filament becomes large in size, it becomes difficult to wrap the filament, and even if the filament is wrapped, The stress remaining in the strip causes cracks, which eventually lead to the reinforced plastic strip breaking.

In addition, in the latter method of wrapping the reinforced plastic filament in an uncured or semi-cured state around the outer periphery of an electric cable and post-curing, the uncured or semi-cured reinforced plastic filament is weak. Sufficient tightening prevents the cable from being wrapped around the outer periphery of the cable, making it difficult to integrate it with the cable.

Furthermore, since the reinforced plastic filament is heated for curing after being wrapped around the outer circumference of the cable, it is necessary to suppress the heating temperature to the extent that it does not adversely affect the cable's constituent materials, and the curing time is extended. As a result, the heating equipment for curing must be lengthened or the speed at which the cable is taken off must be slowed down, resulting in poor manufacturing efficiency.

In particular, this method cannot be used if the electric cable is of a structure that cannot withstand the temperature and time required for curing.

[Means for Solving the Problems] The manufacturing method of the present invention has been made in order to solve the various difficulties of the above-mentioned conventional manufacturing methods. Prior to winding the wire in a spiral around the outer periphery of an electric cable, the filament is heated to a hardening temperature to allow curing to proceed to a state close to complete hardening, and then the filament is heated to the hardenable temperature. It is released from the atmosphere and wrapped around the outer circumference of an electric cable, after which it is completely cured.

[Function] The reinforced plastic striae in an uncured or semi-cured state is
The cable is heated to a curable temperature before being wrapped around the outer circumference of the electrical cable, and the wrapping is later released from the heated atmosphere at the curable temperature. Further, although the filament has been hardened beyond semi-hardening to a state close to completely hardened, it is wound around an electric cable in a state where it is not completely hardened and can be plastically deformed.

[Example] Next, an example of the manufacturing method of the present invention will be described with reference to the drawings. FIG. 1 is a partially sectional side view showing a situation in which the manufacturing method of the present invention is being carried out, and FIG. 2 is a cross-sectional view of a reinforced plastic wire armored cable to be manufactured,
First, an example of a cable structure to which the manufacturing method of the present invention is applied will be described. Reference numeral 2 denotes a three-core twisted wire core, and 3 denotes an inner sheath covering the outer periphery of the twisted wire core 2, which is herein referred to as an electric cable 1. 4 is a reinforced plastic wire sheath wound spirally around the outer periphery of the electric cable l; 5 is the reinforced plastic wire body;
For example, a protective coating 7 is applied to the outer periphery of the reinforced plastic wire core 6 for adhesion prevention and mechanical protection, and 8 is an outer sheath applied to the outer periphery of the reinforced plastic wire sheath 4.

Here, the cross-sectional shape of the reinforced plastic filament 5 is not limited to the circular one shown in the figure, but may be a trapezoid or other commonly known cross-sectional shape, and the material of the filament core 6 may be, for example, Aramid fiber, glass fiber, polyester fiber, polyamide fiber, carbon fiber, ultra-high tensile strength polyethylene fiber, etc., unsaturated polyester, epoxy resin,
Those impregnated with phenolic resin, alkyd resin, silicone resin, etc. and hardened are used. Furthermore, the term "curing" here also includes crosslinking. Further, as the protective coating 7, for example, polyamide, polyvinylidene fluoride, polyether ether ketone, tetrafluoroethylene-hexafluoropropylene copolymer, etc. are used. This is to prevent adjacent filament cores 6 from adhering to each other when the filament cores 6 are heated and hardened, and to protect the filament cores 6 from external forces. Due to the selection of the material of the strip core, the protective coating 7 does not necessarily have to be applied if it also has the properties of a protective coating.

Now, the manufacturing method of the present invention will be explained with reference to FIG. Here, the same reference numerals as in FIG. 2 are used for the same constituent parts as those of the cable in FIG. 2.

In the production line shown in FIG. 1, 10 is a twisting device, 11
51 is the bobbin placed on the twisting device 10, bobbin 1
1 is an uncured or semi-cured reinforced plastic filament sent out from 1; 12 is a dividing plate provided in the twisting device IO;
13 is a heating device also provided in the twisting device IO;
4 is a preheating zone whose temperature is below the curable temperature; 15 is a heating zone whose curable temperature is also the same;
1, the heating zone 15 is the preheating zone 14.
It's further forward.

16 is a preheating medium inlet for the preheating zone 14, 17 is a heating medium inlet for the heating zone 15, 18 is a twisting base provided at the tip of the twisting device IO, and 1 is the center of the twisting device 10. 19 is a guide tube for the electric cable l to run through the inside of the twisting device 10; 5 is a guide tube through which the electric cable l is twisted around the outer periphery of the electric cable l; A hardened reinforced plastic filament, 4 a reinforced plastic filament constructed by the method of the present invention, 20 a take-off device, 2! is a winding device.

The electric cable l fed into the center of the twisting device 10 from the left to the right in FIG. 1 runs through the guide tube I9. On the other hand, the uncured or semi-cured reinforced plastic filament bodies 5I sent out from the pobbin 11 are fed into the twisting device 10, but are first passed through the dividing plate 12 and arranged evenly at equally divided positions on the circumference. Then heating device 13
is fed into the preheating zone 14, and further into the heating zone 15.
Here, it is heated to a temperature that allows it to harden, and curing progresses to a state close to complete hardening. The filament 51 further advances and is twisted at the position of the twisting base 18 around the outer periphery of the electric cable 1 that has passed through the center of the twisting device IO. In order to twist the reinforced plastic filament 51 around the outer periphery of the electric cable 1, either the sending side, that is, the left side of the twisting device IO in the drawing, or the winding side, that is, the right side of the twisting device IO that includes the pulling device 20 in the drawing. Rotate one of them around the axis of travel of the electric cable l.

The filamentous body 51 twisted around the outer periphery of the electric cable l can be hardened after leaving the twisting base 18! However, the curable thermal energy applied while passing through the heating zone 15 is not immediately dissipated, and the curing proceeds thereafter to completely cure the reinforced plastic strand 5. becomes.

In this way, the hardened reinforced plastic wire sheathing 4 is applied to the outer periphery of the electric cable l, which is taken off by the take-up device 20 and wound up by the take-up device 21. Note that the external north 8 of the cable structure shown in FIG. 2 will be further formed in the next step, but is not shown. Here, as the preheating and heating medium for the preheating zone 14 and the heating zone 15, for example, in addition to hot water and steam, silicone oil, paraffin, liquid paraffin, polybutene oil, etc. are used. Alternatively, electric heating such as blowing hot air may be used.

[Effects of the Invention] According to the manufacturing method of the present invention, the reinforced plastic filament in an unconventional or semi-cured state is brought to a temperature at which it can be cured before it is twisted in contact with the outer periphery of an electric cable. After being heated and twisted around the outer circumference of the cable, it is not heated at all, so the electrical cable is not exposed to a high temperature heating atmosphere for curing, and therefore remains in an uncured or semi-cured state. Using the reinforced plastic strand, the hardened reinforced plastic strand can be applied to the outer periphery of an electrical cable without adversely affecting the electrical cable.

In addition, the uncured or semi-cured reinforced plastic filament is accelerated to a state close to complete hardening in the heated atmosphere of the heating zone, and is wrapped around the cable in a strong state, so the reinforced plastic filament Therefore, it is possible to obtain a reinforced plastic wire sheath that does not cause the electric cable to become warm.

Furthermore, although the reinforced plastic filament is already in a state of hardening when it is twisted around the outer circumference of an electric cable, it is not yet completely cured, so it causes plastic deformation surface ridges on the outer circumference of the electric cable. As it arises and wraps around,
There is no fear of cracks occurring due to residual stress (bending strain).

[Brief explanation of the drawing]

FIG. 1 is a partially sectional side view showing an example of a situation in which the present invention is practiced, and FIG. 2 is a cross-sectional view showing an example of the structure of a reinforced plastic wire-inserted cable to be manufactured by the present invention. l: Electrical cable, 2: 3-core twisted insulated wire core, 3: Inner sheath, 4: Reinforced plastic wire armor, 5: Reinforced plastic wire body, 6: Reinforced plastic wire core, 7:
Protective coating, 8: Outer sheath, lO: Twisting device, 11:
Bobbin, 12; Separating plate, I3: Heating device, 14: Preheating zone, I5: Heating zone, 16: Preheating medium population, 17:
Heating medium population, 18: Twisting cap, 19: Guide tube, 20
: Take-up device, 21: Take-up device.

Claims (1)

[Claims] Prior to spirally wrapping an uncured or semi-cured reinforced plastic filament around the outer periphery of an electric cable, the filament is heated to a temperature at which it can be cured to allow curing to proceed to a state close to complete hardening, A method for manufacturing a reinforced plastic wire-inserted cable, characterized in that the filament is then released from the heating atmosphere at the curing temperature and wound around the outer periphery of an electric cable, and then completely cured.