CN110729696A - Strong grounding intermediate joint for submarine cable and installation method thereof - Google Patents

Abstract

The invention discloses a strong grounding intermediate joint for a submarine cable, comprising: an outer insulating protective layer, a stainless steel outer protective shell, a braided net, a stainless steel anchoring device, an optical fiber joint box and an insulating straight-through joint; the two stainless steel anchoring devices are installed in the Both ends of the stainless steel outer protective shell; the stainless steel anchoring device is installed on both ends of the submarine cable, and the stainless steel anchoring device is composed of an anchoring cover plate, an anchor and a hoop; the outer insulating protective layer is completely covered on the The stainless steel outer protective shell and the outer wall of the anchoring cover plate; the optical fibers at both ends of the submarine cable are connected in the optical fiber splice box. Through the above method, the present invention provides a strong grounding intermediate joint for submarine cables and an installation method thereof. The strong grounding intermediate joint has excellent safety performance, waterproof performance, and anti-corrosion performance, and is easy to install and has strong practicability.

Description

Strong grounding intermediate joint for submarine cable and installation method thereof

technical field

The invention belongs to the field of submarine cable intermediate joints, and in particular relates to a strong ground intermediate joint for submarine cables and an installation method thereof.

Background technique

The voltage level of the submarine cable system is high, generally 35kV~500kV, of which the 220kV submarine cable installation intermediate joint is the most common at present. The length of the submarine cable is large, and the length is more than 20km. , is a magnetic material. During the normal operation of the submarine cable system, the armored wire produces large circulating currents and eddy currents, especially for single-core submarine cables, the induced current is even higher than the running current in the conductor.

At present, the stainless steel outer protective shell of the intermediate joint of the submarine cable is directly exposed to the air or the sea, and is directly grounded. It is prone to electrochemical corrosion during long-term operation, and there is also the danger of safety accidents caused by direct contact between people and animals.

In the current intermediate joints of submarine cables, the induced current in the armored wires at both ends of the submarine cable is conducted through the stainless steel anchoring device, the fastening bolts, and the stainless steel outer protective shell, and the resistance at both ends of the armored wires is relatively large. During the process, due to the action of ocean currents and tides, the vibration of the submarine cable itself, and the thermal expansion and contraction of the joint caused by the load change, the fastening bolts are loosened, resulting in an increase in the contact resistance.

To sum up, hot spots are easily formed at the flange of the outer protective shell of the intermediate joint, which may lead to the failure of the intermediate joint after long-term operation. There is no grounding terminal on the outer protective shell, so the grounding treatment cannot be performed.

SUMMARY OF THE INVENTION

The main technical problem solved by the present invention is to provide a strong grounding intermediate joint for a submarine cable and an installation method thereof, which can have excellent safety performance and waterproof performance, convenient installation and strong practicability.

In order to solve the above-mentioned technical problems, a technical solution adopted in the present invention is: a strong grounding intermediate joint for submarine cables, comprising: an outer insulating protective layer, a stainless steel outer protective shell, a braided net, a stainless steel anchoring device, an optical fiber splice box and an insulating straight-through The stainless steel outer protective shell is composed of an upper half shell and a lower half shell, the upper half shell and the lower half shell are connected by fastening bolts, and the upper half shell is provided with plastic injection port;

The two stainless steel anchoring devices are installed at both ends of the stainless steel outer protective shell, and the two ends of the stainless steel outer protective shell are respectively connected with the anchoring cover plate through flanges and fastening bolts;

The stainless steel anchoring device is installed on both ends of the submarine cable. The stainless steel anchoring device is composed of an anchoring cover plate, an anchor and a hoop, and the rear end of the anchoring and the rear end of the anchoring cover plate are fixedly connected by tightening screws. The front end of the anchoring cover plate is connected to the stainless steel outer protective shell by tightening screws, and the front end of the anchoring is fixedly connected to the braided mesh by means of a stainless steel hoop;

The outer insulating protective layer is completely covered on the stainless steel outer protective shell and the outer wall of the anchoring cover plate, and the anchoring cover plate is provided with a ground wire terminal;

The optical fibers at both ends of the submarine cable are continued in the optical fiber splice box, and the optical fiber splice box is placed in the lower half shell of the stainless steel outer protective shell;

Waterproof glue is filled between the stainless steel protective shell, the stainless steel anchoring device, the optical fiber splice box, and the insulating straight-through joint.

In a preferred embodiment of the present invention, the upper half-shell and the lower half-shell are composed of the left and right identical structures.

In a preferred embodiment of the present invention, the connection between the upper half-shell and the lower half-shell, the connection between the left and right parts of the upper half-shell, and the connection between the left and right parts of the lower half-shell are all A rubber seal is installed.

In a preferred embodiment of the present invention, the braided mesh is composed of tinned copper braided tape and armored wire.

In a preferred embodiment of the present invention, the outer insulating protective layer is a heat shrinkable sleeve.

In a preferred embodiment of the present invention, a ground wire terminal is provided on the upper half of the anchoring cover at both ends.

In a preferred embodiment of the present invention, the insulating straight-through joints are, from outside to inside, a protective sleeve, a copper shell, a prefabricated insulating piece and a connecting hardware in sequence.

In a preferred embodiment of the present invention, an electrical connection is achieved between the insulating straight-through joint and the conductors and metal shields at both ends of the submarine cable.

A method for installing a strong grounding intermediate joint for a submarine cable, the specific steps comprising:

(1) Pretreatment: Move both ends of the submarine cable to be connected to a suitable platform, re-weight and fix it to an appropriate length, and preprocess the two ends respectively, so that the armored wire, optical fiber, and conductor are exposed to a suitable length, and Put the armored wire and the optical fiber in the proper position to avoid damage;

(2) Installation joints: After connecting the conductors at both ends of the submarine cable through the connecting fittings, assemble the prefabricated insulating parts to a predetermined position, connect the metal shields at both ends of the submarine cable through the copper shell, and then completely envelop the protective cover;

(3) Optical fiber splicing: the optical fiber at the end of the submarine cable is connected through the optical fiber splice box by using an optical fiber fusion splicer, and the optical fiber splice box is built into the stainless steel outer protective shell;

(4) Install the outer protective shell and the stainless steel anchoring device: fix the braided mesh on the front end of the anchor, tighten the fastening bolts to make the rear end of the anchor and the anchor cover fixedly connected, and the An anchoring cover plate is fixedly connected with the upper half shell and the lower half shell;

(5) Grounding wire installation: Connect the grounding wire that meets the requirements from the reserved grounding wire terminal, and then connect to the main grounding network. If the intermediate joint does not need to be grounded, use epoxy mud to seal the grounding wire. wire terminal;

(6) Outer insulating protective layer: the outer insulating protective layer is completely covered on the stainless steel outer protective shell and the outer wall of the anchoring cover plate by heating;

(7) Filling and sealing layer: pour the waterproof glue from the glue injection port of the stainless steel outer protective shell. After the waterproof glue is completely cured, a strong grounding intermediate joint for submarine cables is obtained. Bend limiters of appropriate lengths are installed on both ends of the joint.

In a preferred embodiment of the present invention, the manufacturing method of the braided net in the step (4) is that after the armor wires at both ends of the submarine cable are reversely tied from the front end of the anchor, the first wire The tinned copper braid with a suitable cross-sectional area is pressed under the first group of the armored wires, and wound out from the second group of the armored wires, and the tinned copper braided tape is connected to the axis of the submarine cable. The angle is 45°, the second tinned copper braided tape of the same cross-sectional area is pressed under the second group of the armoring wires, and wound out on the third group of the armoring wires, the first one is The tinned copper braided tape and the second tinned copper braided tape are next to each other, and so on, and the braiding composed of the tinned copper braided tape and the armoring wire is formed at the anchorage network.

The beneficial effects of the present invention are as follows: a strong grounding intermediate joint for a submarine cable and an installation method thereof of the present invention, the strong grounding intermediate joint has excellent safety performance, waterproof performance, and anti-corrosion performance, is convenient to install, and has strong practicability , There is an outer insulating protective layer outside the stainless steel outer protective shell, which is not directly exposed in water or air to avoid electrochemical corrosion caused by direct grounding, and at the same time effectively prevent people and animals from directly touching and causing safety accidents. The wires are tightly connected by multiple tinned copper braided tapes, the contact resistance is small, the resistance between the armor layers at both ends of the joint is small, and the induced current capacity is large, so as to avoid the induced current being conducted only through the fastening bolts, thus avoiding the stainless steel outer protection The hot spot is generated at the shell flange, which improves the safety, stability and long service life of the submarine cable system. The ground wire terminal is reserved on the anchoring cover, so that the intermediate joint can be directly grounded, adding more grounding schemes for the submarine cable system and improving the Safety and lower construction costs.

Description of drawings

FIG. 1 is a schematic structural diagram of a strong grounding intermediate joint for a submarine cable.

FIG. 2 is a partially enlarged three-dimensional structural schematic diagram of a strong grounding intermediate joint A for a submarine cable.

The components in the accompanying drawings are marked as follows: 1. Outer insulating protective layer; 2. Stainless steel outer protective shell; 3. Waterproof glue; 4. Braided mesh; 5. Stainless steel anchoring device; 6. Optical fiber splice box; ;8, submarine cable; 21, glue injection port; 22, upper half shell; 23, lower half shell; 41, tinned copper braid; 42, armored wire; 51, anchoring cover; 52, anchoring; 53. Hoop; 54. Ground wire terminal.

Detailed ways

The preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings, so that the advantages and features of the present invention can be more easily understood by those skilled in the art, and the protection scope of the present invention can be more clearly defined.

See Figure 1 and Figure 2,

A strong grounding intermediate joint for a submarine cable, comprising: an outer insulating protective layer 1, a stainless steel outer protective shell 2, a braided mesh 4, a stainless steel anchoring device 5, an optical fiber splice box 6 and an insulating straight-through joint 7, the outer insulating protective layer 1 For heat shrinkable sleeve, heat shrinkable sleeve is a new type of environmentally friendly halogen-free flame retardant sleeve, which can provide insulation protection for wires, cables and wire terminals, and is widely used in wire harnesses, solder joints, inductor insulation protection and metal Anti-rust and anti-corrosion of pipes and rods.

The stainless steel outer protective shell 2 is composed of an upper half shell 22 and a lower half shell 23. The upper half shell 22 and the lower half shell 23 are connected by fastening bolts. 22 and the lower half shell 23 are both composed of the same structure on the left and right. Both the left and right parts of the lower half shell 23 are equipped with rubber sealing strips, and the stainless steel outer protective shell 2 adopts the "up, down, left and right" half shell structure, which is convenient for on-site installation and construction of beach joints on the one hand, and on the other hand, through the rubber seal The sealing strip and mechanical parts cooperate to achieve effective waterproof sealing.

The upper half shell 22 is provided with a glue injection port 21, and the glue injection port 21 is used for pouring the waterproof glue 3, thereby forming a waterproof filling layer.

The two stainless steel anchoring devices 5 are installed at both ends of the stainless steel outer protective shell 2, and the two ends of the stainless steel outer protective shell 2 are respectively connected with the anchoring cover plate 51 through flanges and fastening bolts.

The stainless steel anchoring device 5 is installed on both ends of the submarine cable 8. The stainless steel anchoring device 5 is composed of an anchoring cover plate 51, an anchoring 52 and a hoop 53. The rear end of the anchoring 52 is connected to the anchoring cover plate. The rear end of 51 is fixedly connected by fastening screws, the front end of the anchor cover 51 is connected with the stainless steel outer protective shell 2 by fastening screws, and the front end of the anchor 52 is pressed with the woven mesh 4 by a stainless steel hoop 53. Fixed connection, the braided mesh 4 is composed of a tinned copper braided tape 41 and an armored wire 42. The armored wires 42 are tightly connected by a plurality of the tinned copper braided tapes 41, and the contact resistance is small. The resistance between the end armor layers is small, and the capacity of transmitting induced current is large, which avoids the conduction of induced current only through fastening bolts, thereby avoiding hot spots at the flange of the stainless steel outer protective shell 2, and improving the safety of the submarine cable 8 system. Stability and long service life.

The outer insulating protective layer 1 completely covers the outer wall of the stainless steel outer protective shell 2 and the anchoring cover plate 51, and the stainless steel outer protective shell 2 has the outer insulating protective layer 1, so that the strong grounding intermediate joint It is not directly exposed to water or air to avoid electrochemical corrosion caused by direct grounding, and at the same time, it can effectively prevent safety accidents caused by direct contact between people and animals.

The anchoring cover plate 51 is provided with a ground wire terminal 54, and the upper half of the anchoring cover plate 51 at both ends is provided with a ground wire terminal 54. The ground wire terminal 54 can be used for the intermediate joint of the submarine cable 8 as a direct terminal. Grounding treatment, adding more grounding solutions to the submarine cable 8 system, improving safety and reducing construction costs.

The optical fibers at both ends of the submarine cable 8 are continued in the optical fiber splice box 6, and the optical fiber splice box 6 is placed in the lower half shell 23 of the stainless steel outer protective shell 2. The lower half shell 23 is provided with a downwardly protruding groove for accommodating the optical fiber splice box 6 .

The insulating straight-through joint 7 is sequentially composed of a protective sleeve, a copper shell, a prefabricated insulating piece and a connecting hardware from the outside to the inside. The electrical connection between the insulating straight-through joint 7 and the conductors and metal shields at both ends of the submarine cable 8 is realized, so The insulating straight joint 7 is an existing product, so its structure will not be described in detail, and the typical model is YJJJ(T)I.

Waterproof glue 3 is filled between the stainless steel protective shell and the stainless steel anchoring device 5, the optical fiber splice box 6, and the insulating straight-through joint 7. Parts of polyurethane sealing filler are used to solidify a waterproof filling layer between the stainless steel protective shell and the gap between the stainless steel anchoring device 5 , the optical fiber splice box 6 , and the insulating straight-through joint 7 .

A method for installing a strong grounding intermediate joint for a submarine cable, the specific steps comprising:

(1) Pretreatment: move the two ends of the submarine cable 8 to be connected to a suitable platform, re-weight and fix it to an appropriate length, and preprocess the two ends respectively, so that the armored wire 42, the optical fiber and the conductor are exposed to a suitable length , and place the armored wire 42 and the optical fiber in an appropriate position to avoid damage;

(2) Installation joint: After connecting the conductors at both ends of the submarine cable 8 through the connecting fittings, assemble the prefabricated insulating member to a predetermined position, and connect the metal shields at both ends of the submarine cable 8 through the copper shell. , and then completely cover the protective cover;

(3) Optical fiber splicing: using an optical fiber fusion splicer to connect the optical fiber at the end of the submarine cable 8 through the optical fiber splice box 6, and the optical fiber splice box 6 is built in the stainless steel outer protective shell 2;

(4) Install the outer protective shell and the anchoring device: fix the braided mesh 4 on the front end of the anchoring 52, and tighten the fastening bolts so that the rear end of the anchoring 52 and the anchoring cover plate 51 are fixedly connected, and the anchoring cover plate 51 is fixedly connected with the upper half shell 22 and the lower half shell 23;

(5) Grounding wire installation: Connect the grounding wire that meets the requirements from the reserved grounding wire terminal 54, and then connect it to the main grounding network. If the intermediate joint does not need to be grounded, use epoxy mud to seal it. Ground wire terminal 54;

(6) Outer insulating protective layer: the outer insulating protective layer 1 is completely covered on the stainless steel outer protective shell 2 and the outer wall of the anchoring cover plate 51 by heating;

(7) Filling and sealing layer: pour the waterproof glue 3 from the glue injection port 21 of the stainless steel outer protective shell 2. After the waterproof glue 3 is completely cured, a strong grounding intermediate joint for submarine cables is obtained. Bend limiters of suitable length shall be installed at each end of this intermediate joint.

In the step (4), the manufacturing method of the braided mesh 4 is as follows: after the armored wires 42 at both ends of the submarine cable 8 are reversed from the front end of the anchor 53, the first suitable cross-sectional area of the The tinned copper braided tape 41 is pressed under the first group of the armoring wires 42, and is wound out from the second group of the armored wires 42. The angle is 45°, the second tinned copper braid 41 of the same cross-sectional area is pressed under the second group of the armoring wires 42, and is wound out on the third group of the armoring wires 42, the first The first tinned copper braid 41 and the second tinned copper braid 41 are next to each other, and so on. At the anchor 52, the tinned copper braid 41 and the armor are formed The woven mesh 4 is composed of filaments 42 .

Compared with the prior art, the present invention provides a strong grounding intermediate joint for submarine cables and an installation method thereof. The strong grounding intermediate joint has excellent safety performance, waterproof performance, and anti-corrosion performance, is convenient to install, and has strong practicability. , There is an outer insulating protective layer outside the stainless steel outer protective shell, which is not directly exposed in water or air to avoid electrochemical corrosion caused by direct grounding, and at the same time effectively prevent people and animals from directly touching and causing safety accidents. The wires are tightly connected by multiple tinned copper braided tapes, the contact resistance is small, the resistance between the armor layers at both ends of the joint is small, and the induced current capacity is large, so as to avoid the induced current being conducted only through the fastening bolts, thus avoiding the stainless steel outer protection The hot spot is generated at the shell flange, which improves the safety, stability and long service life of the submarine cable system. The ground wire terminal is reserved on the anchoring cover, so that the intermediate joint can be directly grounded, adding more grounding schemes for the submarine cable system and improving the Safety and lower construction costs.

In the description of the present invention, it should be noted that the orientations or positional relationships indicated by the terms "upper", "lower", "left", "right", "inner", "outer", etc. are described based on the accompanying drawings The orientation or positional relationship, or the orientation or positional relationship that the product of the invention is usually placed in use, is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the referred device or element must have a specific orientation, in order to simplify the description. The specific orientation configuration and operation are therefore not to be construed as limitations of the present invention.

The above descriptions are only the embodiments of the present invention, and are not intended to limit the scope of the present invention. Any equivalent structure or equivalent process transformation made by using the contents of the description and drawings of the present invention, or directly or indirectly applied to other related technologies Fields are similarly included in the scope of patent protection of the present invention.

Claims (10)

1. a strong grounding intermediate joint for submarine cable, is characterized in that, comprises: outer insulating protective layer, stainless steel outer protective shell, braided net, stainless steel anchoring device, optical fiber splice box and insulation straight-through joint, described stainless steel outer protective shell is made of The upper half shell and the lower half shell are composed, the upper half shell and the lower half shell are connected by fastening bolts, and the upper half shell is provided with a glue injection port; The two stainless steel anchoring devices are installed at both ends of the stainless steel outer protective shell, and the two ends of the stainless steel outer protective shell are respectively connected with the anchoring cover plate through flanges and fastening bolts; The stainless steel anchoring device is installed on both ends of the submarine cable. The stainless steel anchoring device is composed of an anchoring cover plate, an anchor and a hoop, and the rear end of the anchoring and the rear end of the anchoring cover plate are fixedly connected by tightening screws. The front end of the anchoring cover plate is connected to the stainless steel outer protective shell by tightening screws, and the front end of the anchoring is fixedly connected to the braided mesh by means of a stainless steel hoop; The outer insulating protective layer is completely covered on the stainless steel outer protective shell and the outer wall of the anchoring cover plate, and the anchoring cover plate is provided with a ground wire terminal; The optical fibers at both ends of the submarine cable are continued in the optical fiber splice box, and the optical fiber splice box is placed in the lower half shell of the stainless steel outer protective shell; Waterproof glue is filled between the stainless steel protective shell, the stainless steel anchoring device, the optical fiber splice box, and the insulating straight-through joint. 2 . The strong grounding intermediate joint for a submarine cable according to claim 1 , wherein the upper half-shell and the lower half-shell are composed of left and right identical structures. 3 . 3 . The strong grounding intermediate joint for submarine cable according to claim 1 , wherein the connection between the upper half shell and the lower half shell, and the connection between the left and right parts of the upper half shell. 4 . Rubber sealing strips are installed at the joints with the left and right parts of the lower half shell. 4 . The strong grounding intermediate joint for a submarine cable according to claim 1 , wherein the braided net is composed of tinned copper braided tape and armored wire. 5 . 5 . The strong grounding intermediate joint for a submarine cable according to claim 1 , wherein the outer insulating protective layer is a heat shrinkable sleeve. 6 . 6 . The strong grounding intermediate joint for a submarine cable according to claim 1 , wherein a ground wire terminal is provided on the upper half of the anchoring cover at both ends. 7 . 7 . The strong grounding intermediate joint for a submarine cable according to claim 1 , wherein the insulating straight-through joint is, from outside to inside, a protective sleeve, a copper shell, a prefabricated insulating piece and a connecting fitting in sequence. 8 . 8 . The strong grounding intermediate joint for a submarine cable according to claim 1 , wherein the insulating straight-through joint is electrically connected to the conductors and metal shields at both ends of the submarine cable. 9 . 9. A method for installing a strong ground intermediate joint for a submarine cable, characterized in that the concrete steps include: (1) Pretreatment: Move both ends of the submarine cable to be connected to a suitable platform, re-weight and fix it to an appropriate length, and preprocess the two ends respectively, so that the armored wire, optical fiber, and conductor are exposed to a suitable length, and Put the armored wire and the optical fiber in the proper position to avoid damage; (2) Installation joints: After connecting the conductors at both ends of the submarine cable through the connecting fittings, assemble the prefabricated insulating parts to a predetermined position, connect the metal shields at both ends of the submarine cable through the copper shell, and then completely envelop the protective cover; (3) Optical fiber splicing: the optical fiber at the end of the submarine cable is connected through the optical fiber splice box by using an optical fiber fusion splicer, and the optical fiber splice box is built into the stainless steel outer protective shell; (4) Install the outer protective shell and the stainless steel anchoring device: fix the braided mesh on the front end of the anchor, tighten the fastening bolts to make the rear end of the anchor and the anchor cover fixedly connected, and the An anchoring cover plate is fixedly connected with the upper half shell and the lower half shell; (5) Grounding wire installation: Connect the grounding wire that meets the requirements from the reserved grounding wire terminal, and then connect to the main grounding network. If the intermediate joint does not need to be grounded, use epoxy mud to seal the grounding wire. wire terminal; (6) Outer insulating protective layer: the outer insulating protective layer is completely covered on the stainless steel outer protective shell and the outer wall of the anchoring cover plate by heating; (7) Filling and sealing layer: pour the waterproof glue from the glue injection port of the stainless steel outer protective shell. After the waterproof glue is completely cured, a strong grounding intermediate joint for submarine cables is obtained. Bend limiters of appropriate lengths are installed on both ends of the joint. 10 . The method for installing a strong grounded intermediate joint for submarine cables according to claim 9 , wherein the braided net in the step (4) is manufactured by assembling the armors at both ends of the submarine cable. 11 . After the loading wire is reversed from the front end of the anchor, the first tinned copper braid with a suitable cross-sectional area is pressed under the first group of the armoring wires, and is wound from the second group of the armoring wires. The angle between the tinned copper braided tape and the submarine cable axis is 45°, and the second tinned copper braided tape of the same cross-sectional area is pressed under the second group of the armoring wires, and is placed in the second set of the armored wires. Three sets of the armoring wires are wound out, the first tinned copper braided tape and the second tinned copper braided tape are close together, and so on. The braided net composed of the tin copper braided tape and the armoring wire.

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