KR20170038628A - Submarine cable having bimetallic armours - Google Patents

Abstract

The present invention relates to a submarine cable having heterogeneous armour and, specifically, to a submarine cable which can effectively suppress corrosion of armour made of heterogeneous metal and can avoid an outer diameter increase and structural instability of the cable and damage of the cable when the cable is produced and laid.

Description

{Submarine cable having bimetallic armours}

The present invention relates to a submarine cable having a hetero armor. More specifically, the present invention relates to a submarine cable capable of effectively suppressing corrosion of armor made of dissimilar metals, increasing the outer diameter of the cable, structural instability, and avoiding breakage of the cable upon production and installation of the cable.

The submarine cable is a cable installed in the seabed to transmit power between two isolated points, such as a continent, a continent, a land and an island, etc., It is.

As shown in FIG. 1A, a submarine cable 1000 'generally includes a conductor 110', an inner semiconductive layer 120 'surrounding the inner conductor layer 120', an insulation surrounding the inner semiconductive layer 120 ' A cable core 100 'including a layer 130', an outer semiconductive layer 140 'surrounding the insulating layer 130', and a metal sheath layer 150 'surrounding the outer semiconductive layer 140' And a cable protection layer 600 'surrounding the cable core 100'. The cable protection layer 600 'may include, for example, an inner sheath 610', a metal reinforcing layer 630 ' And may include bedding layers 620 'and 640', an outer sheath 650 ', an armor 660', an outer supporting layer 670 ', and the like disposed above and below the metal reinforcing layer 630'.

1B, the submarine cable 1000 'may include a plurality of cable cores 100' and a cable protection layer 600 'surrounding the plurality of cable cores 100'. Here, the cable core 100 'includes a conductor 110', an inner semiconductive layer 120 'surrounding the conductor 110', an insulating layer 130 'surrounding the inner semiconductive layer 120' A metallic sheath layer 150 'surrounding the outer semiconductive layer 140', and a sheath 160 'surrounding the metallic sheath layer 150', including an outer semiconductive layer 140 'surrounding the layer 130' can do.

Since the submarine cable (1000 ') is installed on the seabed, it is easily damaged by the anchor or fishing gear of the ship in areas where fishing activities are active, and it is damaged by natural phenomena such as sea currents and waves, And typically has an armature 660 'made of metal wire.

The armor 660 'is a structural reinforcement that provides resistance to external damage as well as performing the function of enhancing the mechanical properties and performance of the cable 1000' during handling and installation of the cable. In general, the armor 660 'may be formed by a steel wire having a low carbon content, zinc plated steel, copper, brass, bronze or the like, and a wire having a circular cross section, a square cross section, or the like.

On the other hand, the submarine cable 1000 'is generally installed in water at the time of installation, but part of it is buried in land such as other environments, The rated current of the submarine cable 1000 ', which is the current carrying capability of the submarine cable 1000', is finally determined by the section embedded in the land of the submarine cable 1000 '.

That is, since the magnetic field generated by the current flowing in the conductor 100 'changes, the rotation of the magnetic domain in the wire constituting the armature 660' is made of a ferromagnetic material such as low carbon steel containing high magnetic permeability And the temperature rise due to the magnetic hysteresis loss causes the rated current of the submarine cable 1000 'to be further restricted. The temperature rise due to the magnetic hysteresis loss is caused by the increase of the temperature of the submarine cable 1000' As a consequence, the rated current of the submarine cable 1000 'is greater than the rated current of the submarine cable 1000' on the land of the cable 1000 ', since it is a more serious problem in the land- Which is limited by the buried section and which is also derived from the conductive material of the cable armor 660 ' The same is true for eddy currents.

Accordingly, as shown in FIG. 2, the conventional submarine cable is constructed such that the wire 661a 'constituting the armor of the first section 1100' of cables uses ordinary steel wire and the armature of the second section 1200 ' The constituent wire 661b 'is made of a substantially ferromagnetic non-ferromagnetic metal wire, for example a stainless steel wire, so as to minimize the hysteresis loss and hence the temperature rise, thereby minimizing the rated current limitation of the cable use.

However, in the conventional submarine cable, the steel wire 661a 'and the stainless steel wire 661b' constituting the armor of each portion at the boundary between the first section 1100 'and the second section 1200' When the butt welded portion 664 'and the contact surface 665' of the adjacent steel wire 661a 'and the stainless steel wire 661b' are exposed to electrolytic seawater when they are connected to each other by butt welding or the like, That is, galvanic corrosion is caused, thereby damaging the armor.

On the other hand, as shown in U.S. Patent No. 8,686,290, a conventional undersea cable is formed on the butt weld portion 664 'of the steel wire 661a' and the stainless steel wire 661b 'to suppress the galvanic corrosion. A sacrificial anode such as a zinc rod is bonded in the longitudinal direction, but the sacrificial anode protruded from the wire locally increases the outer diameter of the cable, becomes structurally unstable, and irregularly forms the surface of the cable, There is a possibility of breaking the cable when passing through.

Therefore, there is a strong demand for an undersea cable capable of effectively suppressing the corrosion of armor made of different metals, increasing the outer diameter of the cable, structurally unstable, and preventing the cable from being damaged during production and installation of the cable.

An object of the present invention is to provide a submarine cable capable of effectively suppressing corrosion of an armor made of dissimilar metals.

The present invention also provides an undersea cable capable of avoiding the increase of the outer diameter of the cable and the structural instability and the breakage of the cable in the production and installation of the cable despite adding the means for suppressing the corrosion of the armor made of different metals .

In order to solve the above problems,

A submarine cable comprising at least one cable core and a cable protective layer surrounding the at least one cable core, wherein the submarine cable comprises a first section at least partially submerged in the seabed and a second section at least partially landed on the ground The cable core includes a conductor, an inner semiconductive layer surrounding the conductor, an insulating layer surrounding the inner semiconductive layer, an outer semiconductive layer surrounding the insulating layer, and a metal sheath layer surrounding the outer semiconductive layer, Wherein the armature includes a plurality of metal wires spirally wrapping the one or more cable cores, the metal wires having a first metal wire included in the armor disposed in the first section, A second metal wire included in the armor arranged in the first arm is connected, Wherein the inner wire is made of a first metal material and the second metal wire is made of a second metal material different from the first metal material and the armor is arranged in parallel with the metal wire, And at least one sacrificial anode wire made of a fourth metal material having a lower natural potential than the second metal material.

Here, the first metal wire is plated with a third metal material having a lower natural potential than the first metal material.

Further, the third metallic material is characterized in that the natural potential is smaller than or equal to that of the fourth metallic material.

And, the first metallic material is steel.

Furthermore, the submarine cable is characterized in that the second metallic material is a non-ferromagnetic metal.

Further, the submarine cable is characterized in that the second metallic material is stainless steel.

Here, the fourth metallic material is aluminum, zinc, magnesium or an alloy thereof.

The fourth metallic material is zinc and the third metallic material is zinc or magnesium.

The metal wire is circular or flat in cross section, and the sacrificial anode wire has substantially the same cross-sectional shape and cross-sectional area as the metal wire.

Further, the metal wire has a circular cross-section and a diameter of 3 to 8 mm.

The present invention also provides an undersea cable comprising an electrolyte shielding film for blocking a connection portion between the first metal wire and the second metal wire from an electrolyte.

Further, the submarine cable is characterized in that the surface of the first metal wire, the second metal wire or both of them is coated with a polymer resin.

And a connection portion of the metal wire is covered with a rustproofing agent.

Further, the cable protective layer includes a bedding layer, an armor, and an outer covering layer.

INDUSTRIAL APPLICABILITY The submarine cable according to the present invention effectively suppresses the corrosion of the metal wire constituting the armor, and exhibits an excellent effect of avoiding unnecessary increase of the outer diameter of the cable and the breakage of the cable upon production and installation of the cable.

1A and 1B schematically show a cross-sectional structure of a conventional submarine cable.
2 schematically shows the armor at the boundary of the first section and the second section of a conventional undersea cable.
3A and 3B schematically show a cross-sectional structure of a submarine cable according to the present invention.
4 shows an embodiment of an electrolyte barrier film as corrosion preventing means for armor of a submarine cable according to the present invention.
5 schematically shows a method of providing a heat-shrinkable tube as an electrolyte shielding film in a submarine cable according to the present invention.
6 schematically shows the arrangement of a metal wire and an electrolyte shielding film constituting an armor in a submarine cable according to the present invention.
7 is a schematic view showing an unstable structure of the armor when the number of the electrolyte shielding films disposed on any cross section of the submarine cable according to the present invention is excessive.
8 shows an embodiment of a polymer coating as corrosion protection means for armor of a submarine cable according to the present invention.
Figs. 9 and 10 illustrate an embodiment of a sacrificial anode line as a corrosion preventing means for an armor of a submarine cable according to the present invention.
Figures 11 to 13 illustrate the combination of corrosion prevention means shown in Figures 4 to 10, respectively.

Hereinafter, preferred embodiments of the present invention will be described in detail. However, the present invention is not limited to the embodiments described herein but may be embodied in other forms. Rather, the embodiments disclosed herein are provided so that this disclosure will be thorough and complete, and will fully convey the concept of the invention to those skilled in the art. Like reference numerals designate like elements throughout the specification.

3A and 3B schematically show a cross-sectional structure of a submarine cable according to the present invention.

The submarine cable 1000 according to the present invention is a moving path of electric current for transmission, and is a high-purity copper (Cu) or aluminum (Al) having excellent conductivity and excellent strength and flexibility so as to minimize power loss, A conductor (110) that surrounds the conductor (110), suppresses uneven distribution of electric charges on the surface of the conductor (110), relaxes the electric field distribution from the inside of the cable (1000) An inner semiconductive layer 120 for preventing partial discharge and dielectric breakdown by eliminating a gap between the inner semiconductive layer 110 and a later-described insulating layer 130, and an inner semiconductive layer 120 surrounding the semiconductive semiconductive layer 120 and made of an insulating material such as a polymer resin or insulating paper The insulating layer 130 surrounds the insulating layer 130 to reduce uneven charge distribution between the insulating layer 130 and the metallic sheath layer 150 to be described below to alleviate the electric field distribution, An outer semiconductive layer 140 physically protecting the insulating layer 130 from the metal sheath layer 150 and an outer semiconductive layer 140 surrounding the outer semiconductive layer 140 to uniformize the electric field inside the insulating layer 130, 1000 to prevent the electrostatic shielding effect from being caused to the outside of the cable 1000 and also to act as a return current of the fault current in the event of a short circuit or a short circuit of the cable 1000 through the ground at the end of the cable 1000, At least one cable core (100) including a metal sheath layer (150) that protects the cable (1000) from external shocks, pressures and the like as well as improves water repellency and flame resistance of the cable (1000) A cable protection layer 600 that surrounds the cable core 100 and is disposed at an outer periphery of the cable 1000 to protect the cable 1000 from external impacts or pressures.

The submarine cable 1000 according to the present invention may be applied to a single cable core 100 as shown in FIG. 3A, but may also be applied to a case having a plurality of cable cores 100 as shown in FIG. 3B. The plurality of cable cores 100 may further include an inner sheath 160 surrounding the metal sheath layer 150, respectively.

Here, the cable protection layer 600 may include an inner sheath 610 that improves the corrosion resistance, water repellency and the like of the cable and functions to protect the cable 1000 from mechanical trauma, heat, fire, ultraviolet rays, A metal reinforcing layer 630 that functions to protect the cable 1000 from mechanical impact, a bedding layer 620 and 640 disposed above and below the metal reinforcing layer 630, an ocean current, And an armor 660 formed of a wire or the like, an outer supporting layer 670, and the like. 3B may not include the inner sheath 610, the metal reinforcing layer 630, and the like. The cable protective layer 600 may be formed of the cable The protective layer 600 can be variously designed according to the cable design.

In particular, the armor 660 may be formed by a plurality of metal wires 661 having a circular or flat cross-section and made of metal, and the plurality of metal wires 661 may be made of steel, stainless steel And the like. Here, the diameter of the metal wire 661 may be about 3 to 8 mm.

The submarine cable according to the present invention may include one or more corrosion inhibiting means selected from the group consisting of an electrolyte barrier film, a polymer coating, a sacrificial anode, and the like, which will be described later, as shown in FIGS.

4 shows one embodiment of an electrolyte barrier membrane as a corrosion preventing means for armor of a submarine cable according to the present invention.

4, in the submarine cable 1000 according to the present invention, the armor 660 includes a plurality of metal wires spirally wrapping the one or more cable cores, and the armor 660 is at least partially The first metal wire 661a constituting the armor 660 disposed in the first section 1100 and the armature 660 disposed in the second section 1200 at least partly landed on the ground, And a second metal wire 661b constituting the second metal wire 661b.

Preferably, the first metal wire 661a is made of a first metal material, preferably of low cost and steel with good feed availability and good mechanical properties, while the second metal wire 661b is formed of And may be made of a different second metallic material, preferably a non-ferromagnetic metal that is substantially non-ferromagnetic, for example, stainless steel.

More preferably, the first metal wire 661a may be plated with a third metal material having a lower natural potential than the first metal material constituting the first metal wire 661a, for example, zinc, and the plating layer may be an electrolyte The first metal wire 661a may be negated to be corroded in place of the first metal wire 661a to prevent corrosion of the first metal wire 661a.

The first section 1100 can utilize the cooling action of the seawater and can reduce the heat loss due to magnetic hysteresis loss or eddy current such as eddy current according to the change of the magnetic field generated by the current flowing in the conductor 100 The undersea cable 1000 according to the present invention has such a problem that the first section 1100 is connected to the armature 660 with a relatively low-cost steel wire because the problem of raising the rated current, which is the current carrying capability of the undersea cable, It is possible to achieve the effect of reducing the manufacturing cost of the cable.

On the other hand, since the ambient temperature of the second section 1200 is higher than the seabed by about 10 ° C or more, heat due to energy loss in the form of heat such as magnetic hysteresis loss or eddy current may be a serious problem, The submarine cable 1000 according to the present invention can avoid such a magnetic hysteresis loss in such a second section 1200 because the rated current that is the current carrying capacity of the submarine cable 1000 may decrease or the outer diameter of the submarine cable 1000 may unnecessarily increase By forming the armor 660 with a nonferromagnetic non-ferromagnetic metal, for example, stainless steel wire, which can be minimized, the effect of reducing the rated current of the cable and suppressing unnecessary increase in outer diameter can be achieved.

4, an armor 660 disposed at each of the parts 1100 and 1200 at the boundaries thereof, which is switched from the first section 1100 to the second section 1200 of the submarine cables 1000, The first metal wire 661a and the second metal wire 661b are connected to each other by butt welding or the like and the steel wire as the first metal wire 661a and the stainless steel When the contact point 664 and the contact surface 665 of the adjacent first metal wire 661a and the second metal wire 661b are exposed to an electrolyte such as seawater because the wires are dissimilar dissimilar metals, Galvanic corrosion may occur and the armor 660 may be damaged.

Therefore, the submarine cable according to the present invention can be used as the armor 660 to connect the connecting portions of the first metal wire 661a and the second metal wire 661b constituting the armor 660, for example, The electrolytic shielding film 663 for shielding the electrolytic water from the electrolyte such as seawater can be additionally contained to inhibit galvanic corrosion, which is a dissimilar metal contact corrosion.

The electrolyte shielding film 663 may be formed of, for example, a heat shrinkable tube, an aluminum tape, an adhesive, or the like. The electrolyte shielding film 663 may be formed by bonding the above- Since the cable does not protrude substantially from the surface of the metal wire 661, the protrusion of the conventional sacrificial anode increases the outer diameter of the cable and becomes structurally unstable. Moreover, when the surface of the cable becomes irregular and passes through the cable production and laying path And further shows an excellent effect of suppressing breakage of the cable.

Here, the thickness of the electrolyte barrier layer 663 is preferably 0.01% or less, since the electrolyte barrier layer 663 is difficult to apply to the armor forming process when the thickness of the electrolyte barrier layer 663 is thick and the outer diameter of the electrolyte barrier layer 663 is uniform. To 2 mm, and more preferably 15% or less of the thickness of the metal wire 661.

In the present invention, the connecting portion of the first metal wire 661a and the second metal wire 661b may be coated by applying an anti-rust agent containing aluminum or zinc particles or the like before the heat-shrinkable tube 663 is formed . The rust inhibitor has metal particles with low natural potential contained therein are electrically connected to the first metal wire 661a and the second metal wire 661b to reduce the corrosion of the metal wire 661 by negative electrode Since it performs the function of cathodic protection, it can play an auxiliary role of corrosion prevention.

The rust inhibitor may include 10 to 50% by weight of metal particles having lower natural potential than the first metal material and the second metal material, for example, 30 to 40% by weight, based on the total weight of dimethylether, 25 to 30% by weight of toluol, 20 to 30% by weight of zinc particles, and 15 to 20 parts by weight of an epoxy resin.

In particular, the heat-shrinkable tube as the electrolyte shielding film 663 can be formed by performing the steps (a) to (e) as shown in FIG. 5, It is possible to seal the connection between the metal wire 661a and the second metal wire 661b to prevent penetration of electrolytes such as seawater and to prevent the electrolyte interception 663 from being easily formed, The most preferable from the viewpoints.

The method for forming the heat-shrinkable tube includes the steps of (a) inserting a heat-shrinkable tube as an electrolyte shielding film 663 at an end of a first metal wire 661a, (B) connecting both ends of the wire 661b by butt welding or the like and applying an antirust agent 666 around the connecting portion 664 of the first metal wire 661a and the second metal wire 661b (d) moving the heat-shrinkable tube over the connection portion 664, and (e) heating and shrinking the heat-shrinkable tube.

The heat-shrinkable tube is not particularly limited and may be formed of, for example, a fluororesin, a silicone resin, a polyolefin resin, an ethylene-vinyl acetate copolymer resin, a polyester resin, , An antioxidant, a crosslinking aid, a lubricant, an ultraviolet ray inhibitor, an antistatic agent, a pigment, and the like.

The heat shrinkable tube may have an inner diameter before shrinkage of 8 to 12 mm, an inner diameter of 2.4 to 3.6 mm upon complete shrinkage, and a change in length upon complete shrinkage of about -15% or less. The heat-shrinkable tube may further include an adhesive on the inner surface thereof to further improve the sealing property.

The electrolyte shielding film 663 may be formed by using an aluminum tape layer formed by the transverse direction of the aluminum tape. For example, a thin aluminum tape having a thickness of about 0.01 to 0.07 mm may be laminated on the connecting portion of the first metal wire 661a and the second metal wire 661b by a plurality of layers in the transverse direction to form an aluminum By forming the tape layer, the connection portion can be sealed to block the penetration of electrolytes such as seawater. The aluminum tape has an advantage that the thickness of the aluminum tape layer formed by the transverse direction is thin and light.

For example, it may be an epoxy bond for metal bonding having a high strength of at least about 230 kg / cm 2 and a high heat resistance of 120 ° C or higher, and may be an epoxy bond that does not flow at the time of application It is preferable that the sintering is excellent. The adhesive has a very thin thickness and is easy to be coated, so that it is easy to form the electrolyte shielding film 663.

6 is a schematic view showing the arrangement of the metal wires and the electrolyte barrier film constituting the armor in an arbitrary section of the submarine cable according to the present invention, and Fig. 7 is a cross- And the structure of the armor is unstable when the number of electrolyte shields is excessive.

7, in an arbitrary cross-section of the submarine cable according to the present invention, when the number of electrolyte shielding films 663 disposed on the metal wires 661 constituting the armor 660 is excessive, the metal wires 661 And as a result the metal wire 661 may protrude locally outward to increase the outer diameter of the submarine cable or make the submarine cable structurally unstable.

In order to solve this problem, in the present invention, the connection portions of the first metal wires 661a and the second metal wires 661b are formed to be distributed along the cable longitudinal direction, thereby forming the number of the metal wires 661 A plurality of electrolyte shielding films 663 are formed so as to be dispersed along the cable longitudinal direction so that the number of the electrolyte shielding films 663 is not excessive in any cross section of the submarine cable.

Therefore, the number of the electrolyte barrier film 663, disposed at an arbitrary cross-section of a submarine cable according to the invention is preferably an electrolyte barrier maximum number (N _t) or less, which is defined by the equation (1) below. As a result, the submarine cable according to the present invention can suppress the outer diameter of the submarine cable from being locally increased or structurally unstable by the locally overly arranged electrolyte barrier film 663.

[Equation 1]

N _t = Int [(D _a + D _c ) × π - (Int ((D _a + D _c ) × π × S ÷ D _a ) × D _a )}

In the above equation (1)

D _a is the diameter of the metal wire,

D _c is the outer diameter of the armor inside the submarine cable,

S is the point rate,

t is the thickness of the electrolyte barrier.

Here, the function value Int (x) is an integer which is rounded off to the decimal point of x, and the dot factor S indicates the degree of the clearance space between the metal wires 661. As the dot factor S becomes larger Which means that there is no space, can be defined by the following equation (2) and can be 0.90 or more, for example, 0.95 to 0.98.

&Quot; (2) "

(S) = {(metal wire diameter x metal wire number) / length of circumference connecting center of metal wires}

Here, the dot ratio S is a ratio of the length of the metal wires 661 between the metal wires 661 at a circumferential length L _c connecting the centers of the metal wires around which the metal wires 661 are arranged, Means a ratio of the length occupied by the metal wires 661 excluding the gap, and is a design value predetermined before cable fabrication, and is generally set at 0.95 to 0.98. If the dot ratio S is too small, the space without the metal wire 661 becomes large, which may cause a problem in the role of the armor, and if it is too large, the manufacturing becomes difficult.

The process of deriving the above formula will be described in detail as follows.

L _c = (D _a + D _c ) × π, where L _c is the circumferential length of the circumference of the metal wires 661, that is, the center of the metal wires 661, L _a , L _a = L _c × S, the number N _a of the metal wires 661 arranged in this way becomes equal to Int (L _a / D _a ).

Therefore, the total clearance G _a = L _c - (N _a x D _a ), which is the sum of the clearances between the metal wires 661 around the metal wires 661, is calculated so that the cable is structurally stable (N _t ) can be calculated by N _t = Int (G _a / (t x 2)), which can be expressed by the following equation (1).

If the electrolyte shielding film 663 is formed on the cross-sectional surface of an arbitrary cable, the metal wire can not be properly positioned and lifted as shown in FIG. 7, so that the outer diameter of the cable is increased or structurally unstable .

In the present invention, the above-described problems are not caused by designing the connection portions of the first metal wires 661a and the second metal wires 661b, which are formed with the electrolyte barrier 663, to be distributed along the cable longitudinal direction .

Here, the diameter (D _a ) of the metal wire is 3 to 8 mm, the outer diameter (D _c ) of the inside of the armature in the submarine cable is 80 to 300 mm and the thickness t of the electrolyte barrier film is the heat- 0.5 to 2 mm.

6, in the adjacent metal wires 661 constituting the armor 660, the first metal wire 661a and the second metal wire 661 are connected to the metal wire 661, 661b may be disposed at positions different from each other along the cable longitudinal direction so that the first metal wire 661a of one of the metal wires 661 adjacent to each other in parallel with the other metal wire 661a 661 may come into contact with each other to cause dissimilar metal contact corrosion at the contact surface 665. [

The electrolyte shielding film 663 has a length that can cover the contact surface 665 where the side surfaces of the first metal wire 661a and the second metal wire 661b are in contact with each other in parallel adjacent metal wires 661 To prevent contact between the first metal wire 661a and the second metal wire 661b, and may have a length of, for example, 300 to 500 mm.

On the other hand, when the length of the electrolyte shielding films 663 formed on the parallel metal wires 661 is excessively overlapped with each other, the outer diameter of the cable may be locally increased or the structure of the armor may become unstable.

Therefore, the length of the electrolyte shielding film 663 is set such that the length of the electrolyte shielding film 663 formed in parallel adjacent metal wires 661 does not overlap with each other along the cable longitudinal direction, The first metal wire 661a and the second metal wire 661b constituting the metal wire and the second metal wire 661b constituting the metal wire, The horizontal distance between the connection portions can be adjusted to be shorter than the short horizontal distance.

The first metal wire 661a of one of the adjacent metal wires 661 and the second metal wire 661b of another metal wire 661 are connected to each other, A surface in which the wires 661b come into contact with each other may occur and corrosion of the dissimilar metals may occur on the contact surface 665. In this case, by applying the means for coating the surface of the metal wire to be described later with the polymer resin in parallel, It is possible to solve the problem of contact corrosion of the dissimilar metals at the contact surfaces of the metal wires.

8 shows an embodiment of a polymer coating as corrosion protection means for armor of a submarine cable according to the present invention.

8, a submarine cable according to the present invention is coated with a polymer resin on the surface of the first metal wire 661a, the second metal wire 661b, or both of the metal wires 661 And the polymer resin may include resins such as polyamide, polyethylene, and polypropylene. Wherein the second metal wire (661b) included in the second section, in which the submarine cable is at least partially laid on land, is at least partially located relative to the first metal wire (661a) contained in the first section Since the length is short, the surface of the second metal wire 661b may preferably be coated with a polymer resin. The polymer resin thus formed prevents the contact surface where the side surfaces of the first metal wire 661a and the second metal wire 661b are directly in contact with each other in parallel adjacent metal wires 661, thereby suppressing dissimilar metal contact corrosion can do.

The polymer resin has a density of about 1.4 to 1.6 g / cc for the polyamide resin, a density of about 62 to 150 g / cc for the polyamide resin in order to realize physical properties such as ruggedness, strength, elongation, A tensile strength of MPa, an elongation of about 2 to 20%, and an elastic modulus of about 3.0 to 5.5 GPa.

The polyethylene resin may have a density of about 0.9 to 1.3 g / cc, a tensile strength of about 13 to 200 MPa, an elongation of about 3 to 2200%, an elastic modulus of about 0.6 to 1.3 GPa, The resin may have a density of about 0.9 to 1.8 g / cc, a tensile strength of about 14 to 460 MPa, an elongation of about 8 to 750%, and an elastic modulus of about 0.7 to 3.6 GPa.

The submarine cable according to the present invention is formed by coating the surface of the metal wire 661 constituting the armor 660 with a polymer resin so that the first metal wire 661a, The contact surface where the side surfaces of the two-metal wire 661b are in direct contact with each other is not generated, so that corrosion of the dissimilar metals can be suppressed.

Figs. 9 and 10 illustrate an embodiment of a sacrificial anode line as a corrosion preventing means for an armor of a submarine cable according to the present invention.

9 and 10, the submarine cable according to the present invention is corroded in place of the first metal wire 661a and the second metal wire 661b constituting the armor 660 as the armor 660 And at least one sacrificial anode line 662 that functions to avoid or suppress damage to the armor 660 due to the galvanic corrosion.

The sacrificial anode line 662 has substantially the same cross-sectional shape, diameter, cross-sectional area, and the like as the metal wire 661, unlike the sacrificial anode that is protruded and bonded onto the connection portion of the conventional dissimilar metal wire, The outer diameter of the cable increases due to the protrusion of the conventional sacrificial anode and the surface of the cable becomes irregular so that the cable can be prevented from being damaged when the cable passes through the production and installation paths.

The fourth metal material constituting the sacrificial anode line 662 is a first metal material constituting the first metal wire 661a constituting the armor 660 and a second metal material constituting the second metal wire 661b constituting the armor 660. [ It can have a natural potential lower than that of the material and a natural potential equal to or greater than the natural potential of the third metal material constituting the plating layer of the first metal ion 661a.

In the embodiment of the present invention, steel of -0.46 to 0.65 V is used as the first metal material, and stainless steel of -0.28 V is used as the second metal material, so that the fourth metal material is aluminum, zinc, magnesium (Zn) having a spontaneous potential of -1.07 V, the third metal material constituting the plating layer may be zinc (Zn), or the third metal material constituting the plating layer may be zinc Or magnesium (Mg) having a lower natural potential than that, that is, natural potential -1.6V.

Thus, the sacrificial anode line 662 is electrically connected to the metal wire 661 constituting the armor 660 so as to negate the metal wire 661, thereby performing a negative electrode protection function for suppressing corrosion thereof . In addition, since the plating layer is corroded in comparison with the sacrificial anode line 662, the sacrificial anode line 662 can maintain the external role during the corrosion of the plating layer.

Meanwhile, the sacrificial anode line 662 included in the armor 660 of the submarine cable according to the present invention can design the required total weight in consideration of the cable target lifetime, the sacrificial anode consumption rate, the sacrificial anode generation current, and the like.

The minimum number of sacrificial anode lines 662 required can be obtained by dividing the total weight of the least sacrificial anode lines 662 by one mass according to the design outer diameter of the sacrificial anode line 662, The design exhibits an excellent effect of effectively suppressing the corrosion of the armor 660 during the life of the cable.

Figures 11 to 13 illustrate the combination of corrosion prevention means shown in Figures 4 to 10, respectively.

11, the submarine cable according to the present invention is formed by the electrolyte barrier film 663 at the contact point 664 between the first metal wire 661a and the second metal wire 661b and at the contact point 664 at the contact surface 665 A sacrificial anode line 662, which is corroded in place of the armor 660, is additionally provided for suppressing dissimilar metal contact corrosion, that is, galvanic corrosion, and for preventing the armor 660 from being damaged due to corrosion .

12, the underside cable according to the present invention is formed by coating a non-ferromagnetic metal wire 661b with a polymer resin to form a contact surface 665 between the first metal wire 661a and the second metal wire 661b The sacrificial anode line 662 which is corroded in place of the armor 660 to suppress the damage of the armor 660 due to corrosion even if it occurs, May be further included.

13, the submarine cable according to the present invention has the contact point 664 and the contact surface 665 between the first metal wire 661a and the second metal wire 661b by the electrolyte shielding film 663, The second metal wire 661b may be made of a polymer resin in order to prevent the dissimilar metal contact corrosion in the first metal wire 661b, that is, the galvanic corrosion, and to prevent the electrolyte breaker 663 from covering the contact surface 665 Can be coated.

While the present invention has been particularly shown and described with reference to preferred embodiments thereof, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention as defined in the following claims. . It is therefore to be understood that the modified embodiments are included in the technical scope of the present invention if they basically include elements of the claims of the present invention.

100: Cable core 600: Cable protection layer

Claims (14)

A submarine cable comprising at least one cable core and a cable protective layer surrounding the at least one cable core,
Wherein the submarine cable comprises a first section at least partially laid to the seabed and a second section at least partially laid to land,
The cable core includes a conductor, an inner semiconductive layer surrounding the conductor, an insulation layer surrounding the inner semiconductive layer, an outer semiconductive layer surrounding the insulation layer, and a metal sheath surrounding the outer semiconductive layer,
Wherein the cable protective layer comprises an armor,
Wherein the armature includes a plurality of metal wires helically wrapping the at least one cable core,
Wherein the metal wire is connected to a first metal wire included in the armor disposed in the first section and a second metal wire included in the armor disposed in the second section,
Wherein the first metal wire is made of a first metal material and the second metal wire is made of a second metal material different from the first metal material,
Wherein the armature comprises at least one sacrificial anode wire comprising a fourth metal material arranged in parallel with the metal wire and having a lower natural potential than the first metal material and the second metal material. The method according to claim 1,
Characterized in that the first metal wire is plated with a third metal material having a lower natural potential than the first metal material. 3. The method of claim 2,
Wherein the third metal material has a natural potential smaller than or equal to that of the fourth metal material. The method of claim 3,
Wherein the first metallic material is steel. 5. The method of claim 4,
And the second metallic material is a non-ferromagnetic metal. 6. The method of claim 5,
Wherein the second metallic material is stainless steel. The method according to claim 6,
And the fourth metal material is aluminum, zinc, magnesium or an alloy thereof. The method of claim 3,
Wherein said fourth metallic material is zinc and said third metallic material is zinc or magnesium. 9. The method according to any one of claims 1 to 8,
Wherein the metal wire has a circular or flat cross-section, and the sacrificial anode has a cross-sectional shape and a cross-sectional area that are substantially the same as those of the metal wire. 10. The method of claim 9,
Wherein the metal wire has a circular cross-section and a diameter of 3 to 8 mm. 9. The method according to any one of claims 1 to 8,
And an electrolyte shielding film for shielding a connection portion between the first metal wire and the second metal wire from the electrolyte. 9. The method according to any one of claims 1 to 8,
Characterized in that the surface of the first metal wire, the second metal wire or both are coated with a polymeric resin. 9. The method according to any one of claims 1 to 8,
Wherein a connection portion of the metal wire is coated with a rustproofing agent. 9. The method according to any one of claims 1 to 8,
Characterized in that the cable protective layer comprises a bedding layer, an armor and an outer covering layer.

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