CN114628085A - Dissimilar metal submarine cable conductor and processing method thereof - Google Patents

Abstract

A dissimilar metal submarine cable conductor and a processing method thereof belong to the technical field of submarine cable manufacturing. Copper wire and wire strand synthetic conductor earlier, then weld through non-through metal sleeve pipe and become whole and carry out the conductor connection, guarantee the whole mechanical properties of back conductor and electric property and satisfy the prerequisite of current-carrying capacity requirement, conductor material adopts aluminium or aluminum alloy to replace copper, can effectively reduce conductor manufacturing cost, and realize xenogenesis metallic conductor variable cross section welding through reducing copper conductor section sectional area, can further reduce the manufacturing cost of copper conductor section, and then reduce the manufacturing cost of submarine cable by a wide margin, reach the effect of saving cost increase.

Description

Dissimilar metal submarine cable conductor and processing method thereof

technical field

The invention relates to a dissimilar metal submarine cable conductor with cost saving and utility enhancement and a processing method thereof, belonging to the technical field of submarine cable manufacturing.

Background technique

As an important part of marine engineering development, submarine cables are mainly used for energy transmission in marine engineering fields such as offshore wind power, offshore oil and gas platforms, marine mineral mining, and island power grid interconnection. Traditional submarine cables use copper as the conductor material, but the market price of copper is relatively high. When used for long-distance transmission, the amount of copper is very large. In the composition of the cost of manufacturing a large-length copper-core submarine cable, copper As the cross-sectional area of the submarine cable increases, the proportion of the proportion is also increasing, even more than 50%, resulting in the high manufacturing cost of traditional submarine cables, which is not conducive to the development of offshore wind power. At the same time, due to the high density of copper, with the increase of the laying length of the submarine cable, the weight of the long-length copper-core submarine cable is relatively large, resulting in high installation and laying costs, and the laying efficiency is greatly affected.

As another conductor material, aluminum or aluminum alloy has the characteristics of corrosion resistance, good thermal conductivity, high elongation, good mechanical properties, environmental protection, etc. The price of raw materials is much lower than copper. However, if the submarine cable conductor is simply made of aluminum or aluminum alloy material, the aluminum conductor or aluminum alloy conductor will have a hidden danger of poor contact with the cable terminal end at the submarine cable terminal, and there are potential risks. This is also the case of aluminum core or aluminum alloy core sea. One of the reasons why cables are not widely used in practical projects. If aluminum or aluminum alloy conductors are used instead of copper conductors in the laying area, the cost of the submarine cable can be greatly reduced, and its density is also lower than that of copper, which can effectively reduce the weight of the submarine cable, facilitate laying, and improve efficiency.

The existing energy-saving and efficiency-enhancing submarine cable conductor processing methods mostly use aluminum or aluminum alloy metal wire and copper wire single wire butt welding, then layered and compressed, and adjacent layers are twisted in reverse to form conductors. The process must ensure that the number and diameter of copper wires and aluminum or aluminum alloy wires are equal. In the case of meeting the current carrying capacity requirements, the diameter of the conductor part of the copper wire is often larger than the actual need, resulting in a great waste of materials.

SUMMARY OF THE INVENTION

The purpose of the present invention is to reduce the diameter of the copper wire conductor under the premise of ensuring the overall mechanical and electrical properties of the submarine cable conductor after welding, and to provide a better, variable cross-section dissimilar metal submarine cable for the deficiencies of the above-mentioned prior art Conductor and method of processing the same.

The technical scheme of the present invention is as follows:

The first object of the present invention is to provide a dissimilar metal submarine cable conductor, characterized in that it includes:

Metal conductor 1, which is twisted by copper monofilament;

The second metal conductor is formed by twisting non-copper metal monofilament; the non-copper metal monofilament is aluminum wire or aluminum alloy wire;

The metal sleeve is provided with a partition inside the cavity to divide the cavity of the metal sleeve into two blind installation holes;

The sectional area of the first metal conductor is smaller than the sectional area of the second metal conductor, and the first metal conductor and the second metal conductor are respectively inserted into the two blind installation holes.

The second object of the present invention is to provide a method for processing dissimilar metal submarine cable conductors, which is characterized by comprising the following steps:

1) Prepare copper wire and non-copper metal wire, the metal wire is aluminum wire or aluminum alloy wire; clean the oxide film layer on the surface of copper wire and non-copper metal wire and keep it clean and shiny;

2) Twist and compress several conductor monofilaments of the same material after surface finishing in step 1) to obtain conductors for submarine cables composed of several layers of conductor monofilaments of the same material—metal conductor one (copper conductor), metal conductor Two (non-copper metal conductors);

Use copper wire as a tie wire, tie the ends of the copper conductor and the non-copper metal conductor core respectively, then saw and file them flat, and then grind the surface to ensure that the surface is smooth and free of burrs;

3) Prepare metal bushings. The metal bushings generally use copper bushings considering the electrical connection performance. The cylindrical cavity of the copper bushings is provided with a non-penetrating partition to form two installation blind holes, and the inner diameter of the two blind installation holes is D. ₁ , D2 varies, with the change of the cross _- sectional size of the metal conductors on both sides, the inner diameter tolerance is high, and the inner wall is smooth; the blind holes installed on both sides of the metal sleeve have a smooth inner wall and a tin-plated layer on the surface;

4) Insert the metal conductors of the two materials formed in step 2) into the two blind installation holes from both ends of the metal sleeve, until the ends of the two metal conductors stand against the partition of the metal sleeve;

5) Weld the casing and the metal conductors on both sides respectively to obtain the overall conductor segments with different materials, namely: the part made of copper wire is the copper conductor The part is the conductor metal sleeve section, and the part is completely made of non-copper metal wire material is the non-copper metal wire conductor section;

After welding, use a fine-toothed file to remove the edges and corners caused by the deformation of the end of the metal sleeve during the welding process, polish it with sandpaper, and then wipe it with a cotton cloth rubbed with gasoline. After welding, ensure that the two metal conductors are in good contact with the metal sleeve. , There shall be no transverse cracks at the weld, and no burrs, eccentricity and bending defects are allowed on the surface.

Further, in step 2), the specification of the cross-sectional area of the copper conductor (metal conductor 1) should be smaller than that of the non-copper metal conductor (metal conductor 2), and the current carrying capacity is calculated according to the IEC60287 standard, and the current carrying capacity of the conductor after welding is guaranteed to meet the requirements. Under certain circumstances, the gap between the cross-sectional area of copper conductors and non-copper metal conductors can be up to two levels specified in IEC 60228-2004 or GB/T3956-2008 for the nominal cross-sectional area of cable conductors (for example, the cross-sectional area of non-copper metal conductors is 630mm). ² , the copper conductor cross-sectional area can be reduced to a maximum of 400m ² ).

In step 4), before installing the blind hole cavity on both sides of the metal sleeve and inserting the metal conductor, the oil stains on the inner wall of the blind hole cavity on both sides should be removed first, and then the oxidation on the surface of the tin-plated layer should be wiped off with metal sandpaper. film, and then evenly apply a thin layer of conductive grease; mark the insertion ends of copper conductors and non-copper metal conductors, and apply conductive grease evenly;

The pretreatment work can ensure good electrical contact between the conductors on both sides and the metal sleeve after welding, so as to ensure the good electrical performance of the conductors in the transition section of the butt welding.

In step 5), after welding, the surface of the connecting sleeve should be covered with a layer of metallized paper or two layers of aluminum foil to eliminate the effect of electric field distortion caused by welding pits; the electrical and mechanical properties of the conductor section of the metal sleeve after welding The performance shall comply with the provisions of GB/T 9327.

The welding method of the two dissimilar conductors in the present invention is to weld the stranded dissimilar conductors through a non-connected metal sleeve, which can effectively ensure the mechanical and electrical properties of the conductors after welding, and because of the blind holes on both sides of the metal sleeve The inner diameters D ₁ and D ₂ are variable in size, which can realize the welding connection of dissimilar metal conductors with variable cross-sections.

When the invention is applied, it can ensure that the terminal contact parts at both ends of the submarine cable conductor still retain copper conductor sections, use copper conductors in the land section with poor heat dissipation in the submarine cable laying environment, and replace copper with aluminum in the seabed section with good heat dissipation in the laying environment. Or aluminum alloy, and on the premise of ensuring that the current carrying capacity meets the standard, the cross-sectional area of the copper conductor section can be reduced, the cost of the submarine cable can be reduced by at least 15%, and the manufacturing cost and price of the submarine cable can be greatly reduced.

Compared with the prior art, the submarine cable conductor processing method adopted in the present invention adopts first twisting copper wire and metal wire into a conductor, and then welding the non-penetrating metal sleeve into a whole for conductor connection, so as to ensure the overall mechanical properties of the conductor after welding. On the premise of improving the electrical performance and meeting the requirements of the current carrying capacity, aluminum or aluminum alloy is used as the conductor material instead of copper, which can effectively reduce the cost of conductor manufacturing. The manufacturing cost of the conductor section, thereby greatly reducing the manufacturing cost of the submarine cable, achieves the effect of saving cost and increasing efficiency.

Description of drawings

Fig. 1 is the structural representation of the present invention;

Fig. 2 is the internal structure schematic diagram of the present invention;

3 is a schematic diagram of a conductor segment structure in the present invention;

4 is a cross-sectional view of a copper conductor segment in the present invention;

5 is a cross-sectional view of a non-copper metal conductor segment in the present invention;

In the figure: metal conductor one 1, metal sleeve 2, metal conductor two 3, copper monofilament 4, non-copper metal monofilament 5.

Detailed ways

The present invention is further described below in conjunction with specific embodiment, but the protection scope of the present invention is not limited to this:

Example 1

Dissimilar metal submarine cable conductors, including: metal conductor 1, metal conductor 2 3, metal sleeve 2. As shown in Figures 1 and 2, the conductors for submarine cables are divided into three sections according to different materials, including copper wire conductor sections, conductor metal sleeve sections and non-copper wire conductor sections. In general, it is recommended to be used for conductors with a cross-sectional area of not less than ^400mm2 .

The first metal conductor is formed by twisting copper single wire 4; the second metal conductor is formed by twisting non-copper metal single wire 5, and the non-copper metal single wire is aluminum wire or aluminum alloy wire, as shown in Figures 4 and 5 , The conductor of the submarine cable is made of copper monofilament 4 and non-copper metal monofilament 5 layered and twisted into a circular shape. The cross-sectional area of the metal conductor 1 is smaller than that of the metal conductor 2. The metal sleeve has a partition inside the cavity to divide the cavity of the metal sleeve into two blind installation holes, and the metal conductor 1 and the metal conductor 2 are respectively inserted. in the two blind mounting holes.

Specifically, the method for processing dissimilar metal submarine cable conductors includes the following steps:

1) Clean the oxide film on the surface of copper wire and metal wire and keep it clean and shiny;

2) A number of conductor monofilaments of the same material that have been surface-finished in step 1) are respectively twisted and compressed by a frame stranding machine to obtain a submarine cable conductor composed of several layers of conductor monofilaments of the same material—metal conductor one (copper conductor). ), metal conductor two (non-copper metal conductor);

The specification of the cross-sectional area of the copper conductor (metal conductor 1) should be smaller than that of the non-copper metal conductor (metal conductor 2). The ampacity is calculated according to the IEC60287 standard. Under the condition that the current-carrying capacity of the conductor after welding is guaranteed to meet the requirements, the specification of the cross-sectional area of the copper conductor shall be The gap with non-copper metal conductors can be up to two levels specified in IEC 60228-2004 or GB/T 3956-2008 for the nominal cross-sectional area of cable conductors;

For example, if the cross-sectional area of the non-copper metal conductor is 630mm ² , the cross-sectional area of the copper conductor can be reduced to a maximum of 400m ² , and the overall tensile strength of the welded conductor reaches more than 80% of the tensile strength of the wire conductor;

Then use copper wire as a tie wire, tie the ends of the copper conductor and non-copper metal conductor cores formed by twisting, and then saw and file them flush, and then grind the surface to ensure that the surface is smooth and free of burrs;

3) Prepare metal bushings. The metal bushings generally use copper bushings considering the electrical connection performance. The cylindrical cavity of the copper bushings is provided with a non-penetrating partition to form two installation blind holes, and the inner diameter of the two blind installation holes is D. ₁ , D2 varies, with the change of the cross _- sectional size of the metal conductors on both sides, the inner diameter tolerance is high, and the inner wall is smooth; the blind holes installed on both sides of the metal sleeve have a smooth inner wall and a tin-plated layer on the surface;

4) Insert the metal conductors of the two materials formed in step 2) into the two blind installation holes from both ends of the metal sleeve, until the ends of the two metal conductors stand against the partition of the metal sleeve;

Before installing the blind hole cavity on both sides of the metal sleeve and inserting the metal conductor, the following pretreatment operations are required:

(1) The oil stains on the inner walls of the cavities on both sides should be removed first, then the oxide film on the surface of the tin-plated layer should be wiped off with metal sandpaper, and then a thin layer of conductive grease should be evenly coated;

(2) Make a mark on the copper conductor at a distance of l ₁ ±0.1mm from the insertion end, and apply conductive grease to the cross section of the copper conductor and the conductor surface from the access end to the l ₁ +0.1mm mark. ;

(3) Mark the non-copper metal conductor at the distance l ₂ ±0.1mm from the insertion end, and apply conductive grease to the cross section of the non-copper metal conductor and the conductor surface from the access end to the l ₂ +0.1mm mark. evenly spread;

The pretreatment work can ensure good electrical contact between the conductors on both sides and the metal sleeve after welding, so as to ensure the good electrical performance of the conductors in the transition section of butt welding;

5) Weld the casing and the metal conductors on both sides separately to obtain an overall conductor section with different materials; the obtained submarine cable is formed into three sections with conductors, and the section entirely made of copper wire is the copper conductor section, and the copper wrapped by the metal casing The wire material and the part made of metal wire are the conductor metal sleeve section, and the part completely made of non-copper wire material is the non-copper wire conductor section.

After the metal conductors on both sides are inserted into the copper sleeve, they are respectively placed in the welding mold for welding. After welding, the edge of the welding point and the end of the connecting sleeve should be removed with a fine-tooth file to remove the edges and corners caused by welding, and polished with sandpaper. Wipe clean with a cotton cloth moistened with gasoline. Welds should be smooth, free from cracks and burrs, and free of sharp edges at all edges.

After welding, the surface of the connecting sleeve should be covered with a layer of metallized paper or two layers of aluminum foil to eliminate the effect of electric field distortion caused by welding pits. The electrical and mechanical properties of the metal sleeve conductor section after welding shall comply with the provisions of GB/T 9327.

Example 2

On the basis of embodiment 1, above-mentioned scheme is adjusted:

In step 2), the cross-sectional area of the copper conductor is 400 mm ² , and the cross-sectional area of the non-copper metal conductor is 500 mm ² . After welding, the tensile strength of the connecting section ranges from 160 to 170 MPa, which can reach 85% of the tensile strength of the metal wire (single wire butt welding). , AC resistance and other related electrical performance tests.

As shown in Figure 3, in step 3), the wall thickness t ₁ of the installation blind hole cavity on the copper conductor side of the metal sleeve is not less than 4mm, and the depth l ₁ is not less than 58mm; the blind hole cavity wall on the non-copper metal conductor side is installed Thickness t ₂ is not less than 2mm, depth l ₂ is not less than 80mm; the inner wall of the blind hole cavity is smooth and the surface is coated with tin-plated layer on both sides.

In step 5), after the metal conductors on both sides are inserted into the metal sleeve, they are respectively placed in the welding mold for welding (the metal conductor and the corresponding blind hole for installation), and the distance between the welding points on the non-copper metal conductor side should be away from the sleeve The pipe end should be at least 6mm, and each welding operation point should be at least 7mm apart; the distance between the welding points on the copper conductor side should be at least 7mm from the sleeve end, and each welding operation point should be at least 5mm apart. After welding, use a fine-tooth file to remove the edges and corners of the welding point and the end of the connecting sleeve due to welding, polish with sandpaper, and then wipe clean with cotton cloth dipped in gasoline. Welds should be smooth, free from cracks and burrs, and free of sharp edges at all edges.

The above description of the disclosed embodiments enables any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (10)

1. A dissimilar metal submarine cable conductor, characterized in that it includes: Metal conductor 1, which is twisted by copper monofilament; The second metal conductor is made of non-copper metal monofilament twisted; The metal sleeve is provided with a partition inside the cavity to divide the cavity of the metal sleeve into two blind installation holes; the first metal conductor and the second metal conductor are respectively inserted into the two blind installation holes. 2 . The dissimilar metal submarine cable conductor according to claim 1 , wherein the cross-sectional area of the first metal conductor is smaller than the cross-sectional area of the second metal conductor. 3 . 3. The dissimilar metal submarine cable conductor according to claim 1 or 2, wherein the non-copper metal monofilament is an aluminum wire or an aluminum alloy wire. 4. A method for processing dissimilar metal submarine cable conductors, characterized in that it comprises the following steps: 1) Prepare copper wire and non-copper metal wire, clean the oxide film on the surface of copper wire and non-copper metal wire, and keep it clean and shiny; 2) Twist and compress several conductor monofilaments of the same material processed in step 1) to obtain metal conductor 1 and metal conductor 2 for submarine cables; tie the ends of metal conductor 1 and metal conductor 2 respectively, and then saw Filed flush and polished until the surface is smooth and free of burrs; 3) Prepare a metal sleeve. The cylindrical cavity of the metal sleeve is provided with a non-penetrating partition to form two blind installation holes; 4) Insert the metal conductors of the two materials formed in step 2) into the two blind installation holes from both ends of the metal sleeve, until the ends of the two metal conductors stand against the partition of the metal sleeve; 5) Weld the metal sleeve and the metal conductors on both sides respectively to obtain the overall conductor segments with different materials. 5 . The method for processing dissimilar metal submarine cable conductors according to claim 4 , wherein in step 1), the non-metallic wire is an aluminum wire or an aluminum alloy wire. 6 . 6. The method for processing dissimilar metal submarine cable conductors according to claim 4 or 5, wherein in step 2), the cross-sectional area of the first metal conductor should be smaller than the cross-sectional area of the second metal conductor to ensure that the conductor meets the load after welding. flow requirements. 7 . The method for processing dissimilar metal submarine cable conductors according to claim 6 , wherein in step 3), the metal sleeve is made of copper sleeve, and the inner diameters D ₁ and D ₂ of the two blind installation holes are different. 8 . , which varies with the cross-sectional size of the two metal conductors. 8 . The method for processing dissimilar metal submarine cable conductors according to claim 6 , wherein in step 3), the inner wall of the blind installation hole of the metal sleeve is smooth and clean, and the inner surface is covered with a tin-plated layer. 9 . 9. The method for processing dissimilar metal submarine cable conductors according to claim 6, wherein in step 4), the inner wall of the installation blind hole is evenly coated with a thin layer of conductive grease, and the metal conductors one and two are inserted. Apply conductive grease evenly to the contact surface. 10. The method for processing dissimilar metal submarine cable conductors according to claim 4, wherein in step 5), after the welding is completed, a layer of metallized paper or two layers of aluminum foil is wrapped on the surface of the metal sleeve to eliminate the Welding pits cause electric field distortion.

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