Mpp cable protection pipe

Abstract

The utility model discloses a kind of MPP cable protection pipes, including pipe body, the pipe body is sequentially provided with oxidation resistance layer, fire-retardant layer, corrugated steel band layer and waterproof layer from outside to inside, the inner wall of the waterproof layer is provided with three annular array distribution's recess, the end of the pipe body is provided with connecting sleeve. The utility model is accurate docking by recessing groove in pipe body inner wall, the protruding part of the connecting sleeve set and pipe body recess are matched with bolt reinforcement, without complex fusion operation, reduce construction difficulty, improve efficiency, the sealed cavity that partition part separates and outside heat shrink sleeve form double seal, avoid silt, moisture intrusion junction, both ensure docking accuracy, and enhance connection stability, solve traditional sleeve sealing poor, fusion efficiency low problem, pipe body is formed multiple protection by oxidation resistance layer, fire-retardant layer, corrugated steel band layer and waterproof layer from outside to inside.

Description

Technical Field

[0001] This utility model relates to the field of cable protection technology, specifically to an MPP cable protection pipe. Background Technology

[0002] MPP cable protection pipe, also known as modified polypropylene cable protection pipe, is widely used in power engineering due to its advantages such as corrosion resistance, good insulation performance, light weight, and convenient construction. It is mainly used to protect underground cables from damage by the external environment.

[0003] Existing MPP cable protection pipes are buried underground for a long time. Acidic and alkaline substances in the soil and ions in the groundwater will corrode the outer wall of the protection pipe. At the same time, external oxygen and ultraviolet rays will cause the protection pipe material to age, shorten the service life of the protection pipe, and in severe cases, the pipe may crack, resulting in the cable being exposed and damaged.

[0004] Furthermore, existing MPP cable protection pipes are connected in two ways: one is to use a connecting pipe to sleeve two MPP cable protection pipes, which is too rudimentary and cannot ensure the sealing of the connection between the two pipes; the other is to weld the opposite ends of the two MPP cable protection pipes together (i.e., use an electric heating tool to heat and melt the ends of the protection pipes, and then connect the two protection pipes by pressure). Although this connection method can ensure the sealing of the connection between the two, it is difficult to operate, requires that the connection between the two protection pipes be sufficiently flat, and is time-consuming and inefficient.

[0005] Therefore, it is necessary to invent an MPP cable protection pipe to solve the above problems. Utility Model Content

[0006] The purpose of this invention is to provide an MPP cable protection tube to address the aforementioned shortcomings in the technology.

[0007] To achieve the above objectives, this utility model provides the following technical solution: an MPP cable protection pipe, comprising a pipe body, wherein the pipe body is provided with an anti-oxidation layer, a flame-retardant layer, a corrugated steel strip layer and a waterproof layer from the outside to the inside, the inner wall of the waterproof layer is provided with three grooves arranged in a ring array, and the end of the pipe body is provided with a connecting sleeve; The connecting sleeve includes an inner ring and an outer ring. The outer wall of the inner ring is provided with a protrusion that matches the groove. A partition is provided in the middle part of the connecting sleeve, between the outer ring and the inner ring. The partition divides the space between the outer ring and the inner ring into two independent sealed cavities. The tube is inserted into the sealed cavity at one end of the connecting sleeve.

[0008] As a preferred embodiment of this utility model, each of the protrusions has a threaded hole on its outer surface, and a through hole is provided on the outer ring at the corresponding position of each threaded hole. A bolt is installed in the threaded hole, and the tail end of the bolt is located in the through hole.

[0009] As a preferred embodiment of this utility model, the opposite ends of the two tubes are respectively inserted into the sealing cavities at both ends of the connecting sleeve. The outside of the connecting sleeve and the connection point with the two tubes are wrapped with a heat shrink sleeve, and the inner wall of the heat shrink sleeve is coated with a hot melt adhesive layer.

[0010] As a preferred embodiment of this utility model, the anti-oxidation layer is made of epoxy resin coating, and an antioxidant is added to the epoxy resin coating; the flame retardant layer is made of modified polyvinyl chloride; the corrugated steel strip layer is made of galvanized steel strip with a thickness of 0.8-1.2mm; and the corrugated steel strip layer is bonded and fixed to the flame retardant layer and the waterproof layer by hot melt adhesive.

[0011] As a preferred embodiment of this utility model, the waterproof layer is made of high-density polyethylene with a thickness of 1.2-2mm, the cross-section of the protrusion is semi-circular, the height of the protrusion matches the depth of the groove, the material of the protrusion is elastic rubber, and the length of the groove is equal to the length of the tube.

[0012] The technical effects and advantages provided by this utility model in the above technical solution are as follows: 1. By creating grooves in the inner wall of the pipe, the protrusions of the connecting sleeve precisely align with the grooves in the pipe body, and reinforced with bolts, complex welding operations are eliminated, reducing construction difficulty and improving efficiency. The sealing cavity of the partition section and the outer heat shrink sleeve form a double seal, preventing mud and water from entering the connection. This ensures both the accuracy of the connection and enhances the stability of the connection, solving the problems of poor sealing and low welding efficiency of traditional sleeves. The pipe body is protected by an anti-oxidation layer, a flame-retardant layer, a corrugated steel strip layer, and a waterproof layer from the outside to the inside. Attached Figure Description

[0013] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this utility model. For those skilled in the art, other drawings can be obtained based on these drawings.

[0014] Figure 1 This is a perspective view of the overall structure of this utility model; Figure 2 This is an exploded view of the overall structure of this utility model; Figure 3 This is an exploded view of the tube body of this utility model; Figure 4This is a perspective view of the connecting sleeve of this utility model; Figure 5 This is a cross-sectional view of the connecting sleeve of this utility model; Figure 6 This is a cross-sectional view of the overall structure of this utility model; Figure 7 This is a front view of the tube body of this utility model.

[0015] Explanation of reference numerals in the attached figures: 1. Pipe body; 11. Antioxidant layer; 12. Flame retardant layer; 13. Corrugated steel strip layer; 14. Waterproof layer; 15. Groove; 2. Connecting sleeve; 21. Inner ring; 22. Outer ring; 23. Protrusion; 24. Threaded hole; 25. Bolt; 26. Partition; 3. Heat shrink sleeve. Detailed Implementation

[0016] To enable those skilled in the art to better understand the technical solution of this utility model, the present utility model will be further described in detail below with reference to the accompanying drawings.

[0017] This utility model provides, for example Figure 1-7 The MPP cable protection pipe shown includes a pipe body 1. The pipe body 1 is provided with an anti-oxidation layer 11, a flame retardant layer 12, a corrugated steel strip layer 13 and a waterproof layer 14 from the outside to the inside. The inner wall of the waterproof layer 14 is provided with three grooves 15 arranged in a ring array. The end of the pipe body 1 is provided with a connecting sleeve 2. The connecting sleeve 2 includes an inner ring 21 and an outer ring 22. The outer wall of the inner ring 21 is provided with a protrusion 23 that matches the groove 15. A partition 26 is provided in the middle part of the connecting sleeve 2, between the outer ring 22 and the inner ring 21. The partition 26 divides the space between the outer ring 22 and the inner ring 21 into two independent sealing cavities. The tube 1 is inserted into the sealing cavity at one end of the connecting sleeve 2.

[0018] In this embodiment, the inner ring 21 and outer ring 22 of the connecting sleeve 2 serve as the main load-bearing structure for the insertion of the tube body 1. The inner wall of the outer ring 22 fits against the outer wall of the end of the tube body 1, providing support for the tube body 1. The protrusion 23 on the outer wall of the inner ring 21 cooperates with the groove 15 of the tube body 1 to achieve precise docking between the tube body 1 and the connecting sleeve 2, ensuring the stability of the connection structure. The outer ring 22, the inner ring 21, and the partition 26 of the connecting sleeve 2 together form a sealing cavity, which protects the internal structure and prevents external impurities from entering the sealing cavity and affecting the sealing effect. At the same time, it provides an installation base for the bolts 25, and the connection strength between the tube body 1 and the connecting sleeve 2 is further improved by the reinforcement of the bolts 25.

[0019] Furthermore, in the above technical solution, each protrusion 23 has a threaded hole 24 on its outer surface, and a through hole is provided on the outer ring 22 at the corresponding position of each threaded hole 24. A bolt 25 is installed in the threaded hole 24, and the tail end of the bolt 25 is located in the through hole.

[0020] In this embodiment, the threaded hole 24 is provided on the protrusion 23. Since the pipe body 1 sometimes needs to be cut according to the construction length during use, during the installation of the pipe body 1 and the connecting sleeve 2, a corresponding hole needs to be provided at the end of the pipe body 1 according to the position of the threaded hole 24. The bolt 25 is used to connect and fix the outer ring 22, inner ring 21 of the connecting sleeve 2 and the pipe body 1 together. By tightening the bolt 25, the protrusion 23 can further squeeze the inner wall of the groove 15 of the pipe body 1, enhance the connection tightness between the pipe body 1 and the connecting sleeve 2, and prevent the pipe body 1 from loosening.

[0021] Furthermore, in the above technical solution, the opposite ends of the two tubes 1 are respectively inserted into the sealing cavities at both ends of the connecting sleeve 2. The outside of the connecting sleeve 2 and the connection point with the two tubes 1 are wrapped with a heat shrink sleeve 3, and the inner wall of the heat shrink sleeve 3 is coated with a hot melt adhesive layer.

[0022] In this embodiment, the inner wall of the heat shrink sleeve 3 is coated with a hot melt adhesive layer and is fitted over the connection between the connecting sleeve 2 and the tube body 1. Upon heating, the heat shrink sleeve 3 shrinks, tightly wrapping the connection. Simultaneously, the hot melt adhesive layer melts and fills the gaps, forming a double-sealing structure, further enhancing the sealing performance of the connection and compensating for any potential deficiencies in the sealing of the connecting sleeve. Furthermore, the heat shrink sleeve also protects the ends of the connecting sleeve 2 and the tube body 1, reducing damage to the connection structure from external impacts.

[0023] Furthermore, in the above technical solution, the anti-oxidation layer 11 is made of epoxy resin coating, and an antioxidant is added to the epoxy resin coating; the flame retardant layer 12 is made of modified polyvinyl chloride; the corrugated steel strip layer 13 is made of galvanized steel strip with a thickness of 0.8-1.2mm; and the corrugated steel strip layer 13 is bonded and fixed to the flame retardant layer 12 and the waterproof layer 14 by hot melt adhesive.

[0024] In this embodiment, the anti-oxidation layer 11 is an epoxy resin coating with added antioxidants. Epoxy resin itself has excellent chemical corrosion resistance and can resist the erosion of acidic and alkaline substances in underground soil. Combined with antioxidants, it can effectively delay the aging of materials caused by oxygen and ultraviolet rays, significantly extending the overall service life of the protective pipe and preventing cable exposure and damage due to pipe aging and cracking. The flame-retardant layer 12 is made of modified polyvinyl chloride. The modification treatment enhances its flame-retardant performance. In the event of abnormal conditions such as short circuits and high temperatures in the cable, it can inhibit the spread of flames, reduce the risk of fire accidents, provide safety protection for cable operation, and make up for the deficiency of insufficient flame-retardant capability of traditional MPP protective pipes. The corrugated steel strip layer 13 is made of 0.8-1.2mm thick galvanized steel strip. The galvanized layer can prevent the steel strip from rusting and extend its service life. The corrugated structure can disperse and withstand underground soil pressure, ground load, and construction machinery impact, significantly improving the compressive and impact resistance of the pipe body and preventing pipe deformation and breakage.

[0025] Furthermore, in the above technical solution, the waterproof layer 14 is made of high-density polyethylene with a thickness of 1.2-2mm, the cross-section of the protrusion 23 is semi-circular, the height of the protrusion 23 matches the depth of the groove 15, and the material of the protrusion 23 is elastic rubber, and the length of the groove 15 is equal to the length of the tube 1.

[0026] In this embodiment, the waterproof layer 14 is made of high-density polyethylene. High-density polyethylene has excellent waterproof properties, effectively preventing groundwater from seeping into the pipe, protecting the cable insulation performance, and preventing cable failure due to moisture. Its material also has a certain degree of wear resistance, reducing wear on the pipe body caused by underground debris. The groove 15 is formed on the inner wall of the waterproof layer, arranged in a three-ring array, with a length consistent with the pipe body. On one hand, it matches the protrusion 23 of the connecting sleeve 2, enabling quick positioning of the pipe body 1 and the connecting sleeve 2, improving docking accuracy. On the other hand, it enhances the connection stability between the pipe body 1 and the connecting sleeve 2, preventing the pipe body 1 from rotating or shifting inside the connecting sleeve 2. Simultaneously, the structure of the groove 15 can also reduce the weight of the pipe body to a certain extent, balancing practicality and economy. The protrusion 23 has a semi-circular cross-section, is made of elastic rubber, and its height matches the depth of the groove 15. The elastic rubber material has a certain deformation capacity, which can accommodate minor errors during installation, ensuring a tight fit with the groove 15 and enhancing the connection seal; the semi-circular structure reduces the frictional resistance between the protrusion 23 and the groove 15 during installation, making it easier for the tube 1 to be inserted into the connecting sleeve 2, thus improving installation convenience. The working process of the MPP cable protection pipe provided by this utility model is as follows: Take out a tube 1 and align its end with the sealing cavity at one end of the connecting sleeve 2, so that the groove 15 on the inner wall of the tube 1 is aligned with the protrusion 23 on the inner ring 21 of the connecting sleeve 2 (see reference). Figure 2 , Figure 4Slowly insert the tube body 1 until the end of the tube body 1 abuts against the partition part 26 of the connecting sleeve 2.

[0027] In the same manner, insert the other tube 1 into the sealing cavity at the other end of the connecting sleeve 2, ensuring that the opposite ends of the two tubes 1 are parallel and without offset within the connecting sleeve 2 (refer to...). Figure 6 ).

[0028] Mark the position of the threaded hole 24 on the protrusion 23 of the connecting sleeve 2 with a marker on the tube body 1. Then temporarily remove the tube body 1 and drill a hole on the tube body 1 according to the mark (the hole diameter is the same as the through hole size on the outer ring 22 of the connecting sleeve 2).

[0029] Reinsert the pipe body 1 into the sealing cavity of the connecting sleeve 2, pass the bolt 25 through the through hole of the outer ring 22 of the connecting sleeve 2 and the drilled hole on the pipe body 1, and screw it into the threaded hole 24 of the protrusion 23 (see reference). Figure 5 Ensure that the pipe body 1 and the connecting sleeve 2 are tightly fixed and without loosening.

[0030] Then, remove the heat shrink sleeve 3 and place it over the connecting sleeve 2, aligning the center of the heat shrink sleeve 3 with the center of the connecting sleeve 2, with both ends of the heat shrink sleeve 3 covering the outer sides of the ends of the tube body 1 (see reference). Figure 1 ).

[0031] Use a hot air gun to heat the heat shrink sleeve 3 evenly from the middle to both ends, and control the heating temperature at 120-140℃ (the melting temperature of the hot melt adhesive layer). Observe the heat shrink sleeve 3 gradually shrinking until it tightly fits the connecting sleeve 2 and the outer wall of the tube body 1. The inner hot melt adhesive layer melts and fills the gap, forming a seal.

[0032] The foregoing description only illustrates certain exemplary embodiments of the present invention. Undoubtedly, those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the above drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. An MPP cable protection pipe, comprising a pipe body (1), characterized in that: The pipe body (1) is provided with an anti-oxidation layer (11), a flame retardant layer (12), a corrugated steel strip layer (13) and a waterproof layer (14) from the outside to the inside. The inner wall of the waterproof layer (14) is provided with three grooves (15) arranged in a ring array. The end of the pipe body (1) is provided with a connecting sleeve (2). The connecting sleeve (2) includes an inner ring (21) and an outer ring (22). The outer wall of the inner ring (21) is provided with a protrusion (23) that matches the groove (15). A partition (26) is provided in the middle part of the connecting sleeve (2) between the outer ring (22) and the inner ring (21). The partition (26) divides the space between the outer ring (22) and the inner ring (21) into two independent sealed cavities. The tube (1) is inserted into the sealed cavity at one end of the connecting sleeve (2).

2. The MPP cable protection pipe according to claim 1, characterized in that: Each of the protrusions (23) has a threaded hole (24) on its outer surface. A through hole is provided on the outer ring (22) at the corresponding position of each threaded hole (24). A bolt (25) is installed in the threaded hole (24), and the tail end of the bolt (25) is located in the through hole.

3. The MPP cable protection pipe according to claim 1, characterized in that: The opposite ends of the two tubes (1) are respectively inserted into the sealing cavities at both ends of the connecting sleeve (2). The outside of the connecting sleeve (2) and the connection point with the two tubes (1) are wrapped with heat shrink sleeves (3). The inner wall of the heat shrink sleeve (3) is coated with a hot melt adhesive layer.

4. The MPP cable protection pipe according to claim 1, characterized in that: The antioxidant layer (11) is made of epoxy resin coating and contains antioxidants. The flame retardant layer (12) is made of modified polyvinyl chloride. The corrugated steel strip layer (13) is made of galvanized steel strip with a thickness of 0.8-1.2mm. The corrugated steel strip layer (13) is bonded and fixed to the flame retardant layer (12) and the waterproof layer (14) by hot melt adhesive.

5. The MPP cable protection pipe according to claim 1, characterized in that: The waterproof layer (14) is made of high-density polyethylene with a thickness of 1.2-2mm. The cross-section of the protrusion (23) is semi-circular. The height of the protrusion (23) matches the depth of the groove (15). The material of the protrusion (23) is elastic rubber. The length of the groove (15) is equal to the length of the tube (1).

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