A mold for repairing the insulation layer of a submarine cable flexible joint based on distributed strain field monitoring

Abstract

The utility model provides a kind of mould for repairing insulating layer of submarine cable flexible joint based on distributed strain field monitoring, belong to cable technical field, including pouring mould, it is characterized in that, the pouring mould includes inner mould, outer mould and strain gauge, the inner mould is silica gel cover, the inner mould is dumbbell type setting, and the measuring point including temperature compensation sheet and measurement strain sheet is set on the inner mould, the temperature compensation sheet is set along inner mould axial direction, the measurement strain sheet is set along inner mould circumference, the outer mould includes upper cover and lower cover, the upper cover and lower cover are oppositely set on the outer side of the inner mould, pouring hole is set on the upper cover, the strain gauge is connected with the measuring point electric signal line, and the pouring density and pouring quality can be improved by the mould and monitoring method, the insulating layer pouring repair process of flexible joint is monitored in real time, and product quality is ensured.

Description

Technical Field

[0001] This utility model belongs to the field of cable technology, and specifically relates to a mold for repairing the insulation layer of submarine cable flexible joints based on distributed strain field monitoring. Background Technology

[0002] With the increasing global demand for renewable energy, especially the rapid development of offshore wind farms, the demand for marine cables has risen significantly, and their size and length have also increased substantially. For long-length marine cables, due to limitations in production equipment, they usually need to be manufactured in sections and then connected using flexible joints. Flexible joints are a key component of marine cables, requiring not only electrical properties similar to the cable itself, but also high standards in mechanical strength, corrosion resistance, and service life. Their quality directly affects the overall performance of the cable.

[0003] During the manufacturing process of flexible joints, defects such as impurities, air bubbles, or pores can easily occur in the insulation layer, leading to uneven electric field distribution, inducing breakdown, and ultimately damaging the entire cable. Therefore, insulation layer repair is a crucial step in ensuring the long-term stable operation of the cable. Currently, the insulation layer repair of flexible joints is mostly carried out using a mold extrusion casting method, where insulating material is injected into the flexible joint through a mold to repair the damaged insulation layer. However, this method has certain limitations. Due to the enclosed nature of the mold, construction personnel cannot directly observe the casting process inside the mold. They mostly rely on overflow observation, judging whether the casting is complete by whether insulating material is extruded from both sides of the flexible joint. This indirect judgment method may lead to uneven casting or defects such as air bubbles, thus affecting the electrical performance and mechanical strength of the flexible joint. Utility Model Content

[0004] In view of this, the present invention provides a mold for repairing the insulation layer of submarine cable flexible joints based on distributed strain field monitoring. The mold and monitoring method can improve the casting density and casting quality, monitor the casting and repair process of the flexible joint insulation layer in real time, and ensure product quality.

[0005] This utility model is implemented as follows:

[0006] This utility model provides a mold for repairing the insulation layer of a submarine cable flexible joint based on distributed strain field monitoring, including a casting mold. The casting mold includes an inner mold, an outer mold, and a strain gauge. The inner mold is a silicone sleeve and is dumbbell-shaped. The measuring point on the inner mold includes a temperature compensation plate and a strain gauge. The temperature compensation plate is arranged axially along the inner mold, and the strain gauge is arranged circumferentially along the inner mold. The outer mold includes an upper cover and a lower cover, which are arranged opposite to each other on the outside of the inner mold. A casting hole is provided on the upper cover, and a through hole is opened on the inner mold. The strain gauge is connected to the measuring point via an electrical signal line corresponding to the casting hole and the through hole.

[0007] Based on the above technical solution, the mold for repairing the insulation layer of submarine cable flexible joints based on distributed strain field monitoring of this utility model can be further improved as follows:

[0008] Furthermore, the temperature compensation gauge and the strain gauge are arranged in a T-shape.

[0009] Furthermore, the temperature compensation gauge and the strain gauge are made of nickel alloy.

[0010] Made of chromium-nickel alloy, suitable for high-temperature environments, and highly sensitive.

[0011] Furthermore, both the upper and lower covers are arc-shaped, with a sliding groove on the upper cover and a protrusion on the lower cover, the protrusion slidingly engaging with the sliding groove.

[0012] Furthermore, at the junction of the inner wall of the outer mold and the outer wall of the inner mold.

[0013] Furthermore, an upper fixing block is provided on the upper cover, and a lower fixing block is provided on the lower cover. The upper fixing block and the lower fixing block are fixed by bolts.

[0014] Furthermore, the metal is made of stainless steel.

[0015] Furthermore, a first groove and a second groove are provided on the upper cover, and a first groove and a second groove are provided on the lower cover. The first groove is arranged along the axial direction, and the second groove is arranged radially at both ends of the inner wall of the upper cover and the lower cover. The first groove and the second groove are interconnected.

[0016] Furthermore, a rubber pad is placed in the second groove, and an electrical signal line is placed in the first groove.

[0017] By placing a rubber pad in the second groove, the upper and lower covers can be fastened together. Different thicknesses of rubber pads can be used to adjust the gap between the inner mold and the cable, facilitating the expulsion of internal air.

[0018] The first groove facilitates the routing of electrical signal lines outside the mold to connect with a strain gauge, enabling easy measurement of the strain gauge.

[0019] Compared with existing technologies, the beneficial effects of the mold for repairing the insulation layer of submarine cable flexible joints based on distributed strain field monitoring provided by this utility model are:

[0020] The mold adopts a dumbbell-shaped silicone inner mold and a metal outer mold structure design. It applies uniform circumferential pressure to the insulating material through the radial shrinkage force after the silicone sleeve deforms, thereby controlling the material flow and dense filling.

[0021] By strategically arranging strain gauges on the outer side of the inner mold of the silicone sleeve, the deformation degree of the silicone sleeve can be inferred from the strain on its outer surface, thus revealing the pouring status of the insulating material. The pouring quality can be inferred from the deformation of the inner mold. Compared to the traditional method of observing overflow in molds, this method allows for quantitative observation of pouring completion through deformation values. Since the insulating material needs to be extruded at high temperatures, and temperature has a significant impact on the measurement results, strategically arranging strain gauges as temperature compensation devices eliminates the influence of temperature on the measurement results, thereby improving measurement accuracy. Attached Figure Description

[0022] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this utility model and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained from these drawings without creative effort.

[0023] Figure 1 This utility model provides a schematic diagram of the inner mold for repairing the insulation layer of a submarine cable flexible joint based on distributed strain field monitoring.

[0024] Figure 2 This utility model provides a schematic diagram of a mold cover for repairing the insulation layer of a submarine cable flexible joint based on distributed strain field monitoring;

[0025] Figure 3 This utility model provides a schematic diagram of the lower cover of a mold for repairing the insulation layer of a submarine cable flexible joint based on distributed strain field monitoring;

[0026] Figure 4 This utility model provides a schematic diagram of the cross-section of a mold for insulation repair of submarine cable flexible joints based on distributed strain field monitoring;

[0027] Figure 5 This utility model provides a schematic diagram of the calculation principle of a mold for insulation repair of submarine cable flexible joints based on distributed strain field monitoring.

[0028] The attached diagram lists the components represented by each number as follows:

[0029] 10. Inner mold; 11. Temperature compensation plate; 12. Strain gauge; 201. First groove; 202. Second groove; 21. Top cover; 211. Casting hole; 212. Slide groove; 213. Upper fixing block; 22. Lower cover; 222. Protrusion; 223. Lower fixing block. Detailed Implementation

[0030] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0031] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0032] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0033] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0034] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0035] like Figure 1-4 As shown, this utility model provides a mold for repairing the insulation layer of a submarine cable flexible joint based on distributed strain field monitoring. The mold includes a casting mold, which comprises an inner mold 10, an outer mold, and a strain gauge. The inner mold 10 is a silicone sleeve and is dumbbell-shaped. Measurement points, including a temperature compensation plate 11 and a strain gauge 12, are provided on the inner mold 10. The temperature compensation plate 11 and the strain gauge 12 are T-shaped. The temperature compensation plate 11 is axially arranged along the inner mold 10, and the strain gauge 12 is circumferentially arranged along the inner mold 10. The strain gauge is connected to the strain gauge 12 by an electrical signal line.

[0036] Strain gauges expand and contract with temperature, causing changes in resistance. Therefore, an identical strain gauge, namely a temperature compensation gauge 11, is attached near the strain gauge 12. The temperature compensation gauge 11 will not deform due to changes in the object, but will only be affected by temperature. By measuring the change in resistance of the strain gauge 12 and subtracting the change in resistance of the temperature compensation gauge, the change in resistance caused by the deformation of the object can be obtained, and the deformation of the object can be calculated.

[0037] Strain gauges are generally rectangular and can only measure deformation along their length. Since the silicone sleeve only undergoes expansion deformation during casting and does not deform axially, the length direction of strain gauge 12 on the silicone sleeve is along the circumference of the silicone sleeve, while the temperature compensation gauge 11 is arranged along the axial direction.

[0038] The outer mold includes an upper cover 21 and a lower cover 22, which are disposed opposite to each other on the outer side of the inner mold 10. At the junction of the inner wall of the upper cover 21 and the outer wall of the inner mold 10, a first groove 201 and a second groove 202 are formed on the upper cover 21, and a first groove 201 and a second groove 202 are formed on the lower cover 22. The first groove 201 is arranged along the axial direction, and the second groove 202 is radially arranged at both ends of the inner wall of the upper cover 21 and the lower cover 22. The first groove 201 and the second groove 202 are interconnected.

[0039] A rubber pad is placed in the second groove 202, and an electrical signal line is placed in the first groove 201.

[0040] The strain gauge has multiple electrical signal lines connected to multiple measuring strain gauges 12, which simultaneously measure and observe the deformation at each measuring point in real time. Since the electrical signal lines are thin, they can all be led out from the first groove 201.

[0041] A casting hole 211 is provided on the upper cover 21, through which insulating material can be extruded into the inner mold 10. During the extrusion process, the deformation and casting degree of the silicone sleeve can be inferred by the surface strain of the silicone sleeve. The inference method is as follows:

[0042] Calculation principle as follows Figure 5 As shown, based on the similarity of circles, the following formula can be written:

[0043] In the formula, l is the arc length of the silicone sleeve before deformation. denoted as , where is the change in arc length after deformation; 'r' is the radius of the silicone sleeve before deformation. This represents the change in radius after deformation.

[0044] Simplification yields

[0045]

[0046] In the formula, , which is the strain of the measured strain gauge 12.

[0047] The deformation of the silicone sleeve during the insulation repair process can be obtained from the data measured by the strain gauge 12 using the above formula, thereby monitoring the pouring of the internal insulation material.

[0048] Both the upper cover 21 and the lower cover 22 are arc-shaped. A groove 212 is provided on the upper cover 21, and a protrusion 222 is provided on the lower cover 22. The protrusion 222 slides and engages with the groove 212.

[0049] An upper fixing block 213 is provided on the upper cover 21, and a lower fixing block 223 is provided on the lower cover 22. The upper fixing block 213 and the lower fixing block 223 are fixed by bolts.

[0050] Before use, the insulation layer of the cable to be repaired is cut and ground into a conical shape. Compared with grinding it into a vertical surface, the contact surface is inclined, which can increase the contact area for the insulation material to be squeezed in, improve the mechanical strength of the repair, avoid squeezing defects, and improve the repair quality.

[0051] In use, first, the silicone inner mold 10 with temperature compensation plate 11 and strain gauge 12 is fitted onto the cable to be repaired. Multiple electrical signal lines of the strain gauge are connected to multiple strain gauges 12. Then, the outer mold is installed, and multiple electrical signal lines are led out from the first groove 201. The upper cover 21 and lower cover 22 are placed above and below the inner mold 10. The protrusion 222 of the lower cover 22 is slid into the groove 212 of the upper cover 21. After the upper cover 21 and lower cover 22 are closed, bolts are inserted into the upper fixing block 213 and lower fixing block 212. 23. Further fixation is performed by inserting the extruder outlet into the casting hole 211 and the through hole of the inner mold 10. Insulating material is extruded into the mold through the casting hole 211 and the through hole of the inner mold 10. The extruded material enters the cavity between the insulating layer and the inner mold 10. During the extrusion process, the shape and casting degree of the silicone sleeve are inferred by the surface strain of the silicone sleeve. When all the strain gauges 12 reach their maximum values, it indicates that the extrusion is complete. A small amount of material leaks onto the inner mold 10 during the extrusion process, but this will not affect the measurement results.

[0052] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A mold for repairing the insulation layer of a submarine cable flexible joint based on distributed strain field monitoring, comprising a casting mold, characterized in that, The casting mold includes an inner mold (10), an outer mold, and a strain gauge. The inner mold (10) is a silicone sleeve and is dumbbell-shaped. The measuring point is provided on the inner mold (10), including a temperature compensation plate (11) and a measuring strain gauge (12). The temperature compensation plate (11) is arranged axially along the inner mold (10), and the measuring strain gauge (12) is arranged circumferentially along the inner mold (10). The outer mold includes an upper cover (21) and a lower cover (22). The upper cover (21) and the lower cover (22) are arranged opposite to each other on the outside of the inner mold (10). A casting hole (211) is provided on the upper cover (21), and a through hole is opened on the inner mold (10). The casting hole (211) is arranged corresponding to the through hole. The strain gauge is connected to the electrical signal line of the measuring point.

2. The mold for repairing the insulation layer of a submarine cable flexible joint based on distributed strain field monitoring as described in claim 1, characterized in that, The temperature compensation plate (11) and the measuring strain gauge (12) are arranged in a T-shape.

3. A mold for repairing the insulation layer of a submarine cable flexible joint based on distributed strain field monitoring, as described in claim 2, is characterized in that... The temperature compensation plate (11) and the strain gauge (12) are made of nickel alloy.

4. A mold for repairing the insulation layer of a submarine cable flexible joint based on distributed strain field monitoring, as described in claim 1, is characterized in that... Both the upper cover (21) and the lower cover (22) are arc-shaped. A groove (212) is provided on the upper cover (21), and a protrusion (222) is provided on the lower cover (22). The protrusion (222) slides in the groove (212).

5. A mold for repairing the insulation layer of a submarine cable flexible joint based on distributed strain field monitoring, as described in claim 1, is characterized in that... The inner wall of the outer mold is connected to the outer wall of the inner mold (10).

6. A mold for repairing the insulation layer of a submarine cable flexible joint based on distributed strain field monitoring, as described in claim 1, is characterized in that... An upper fixing block (213) is provided on the upper cover (21), and a lower fixing block (223) is provided on the lower cover (22). The upper fixing block (213) and the lower fixing block (223) are fixed by bolts.

7. A mold for repairing the insulation layer of a submarine cable flexible joint based on distributed strain field monitoring, as described in claim 1, is characterized in that... The outer mold is made of metal.

8. A mold for repairing the insulation layer of a submarine cable flexible joint based on distributed strain field monitoring, as described in claim 7, is characterized in that... The metal is made of stainless steel.

9. A mold for repairing the insulation layer of a submarine cable flexible joint based on distributed strain field monitoring, as described in claim 1, is characterized in that... A first groove (201) and a second groove (202) are provided on the upper cover (21), and a first groove (201) and a second groove (202) are provided on the lower cover (22). The first groove (201) is arranged along the axial direction, and the second groove (202) is arranged radially at both ends of the inner wall of the upper cover (21) and the lower cover (22). The first groove (201) and the second groove (202) are interconnected.

10. A mold for repairing the insulation layer of a submarine cable flexible joint based on distributed strain field monitoring, as described in claim 9, is characterized in that... A silicone pad is placed in the second groove, and an electrical signal line is placed in the first groove.

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