Flame-retardant power cable protection tube

Abstract

The utility model relates to the technical field of protection tubes, in particular to a flame-retardant power cable protection tube, which comprises a modified polypropylene tube, a chlorinated polyvinyl chloride tube is sleeved on the outer side of the modified polypropylene tube, connecting rings are arranged at the end parts of the modified polypropylene tube and the chlorinated polyvinyl chloride tube, and bolt holes are formed in the surfaces of the connecting rings. Two groups of screws are arranged on the surface of the connecting ring, penetrate through the connecting ring and then are in threaded connection with the end parts of the modified polypropylene pipe and the chlorinated polyvinyl chloride pipe respectively; the double-layer pipeline has the beneficial effects that the double-layer pipeline formed by the modified polypropylene pipe and the chlorinated polyvinyl chloride pipe is adopted, so that the flame-retardant effect is improved, and the compression-resistant effect is improved; and the connecting rings are adopted, so that the modified polypropylene pipe and the chlorinated polyvinyl chloride pipe are connected, and the two adjacent groups of protection pipes are connected.

Description

TECHNICAL FIELD

[0001] The utility model relates to the field of protection pipe, concretely to a kind of flame-retardant power cable protection pipe. BACKGROUND

[0002] Traditional single-layer flame-retardant power cable protection pipe is mainly made of single material (such as PVC or CPVC added with flame retardant), which has the following defects:

[0003] Single flame-retardant performance: relying on flame retardant to achieve flame-retardant effect, the flame-retardant grade is usually B or C, and smoke and corrosive gas are easily produced during combustion, and the light transmittance is low.

[0004] Insufficient compressive strength: the compressive strength is generally 16-25MPa, and the nominal pressure is only 0.6-1.6MPa, which is difficult to meet the needs of complex construction environment (such as non-excavation crossing and deep buried engineering).

[0005] High maintenance cost: once the single-layer structure is damaged, the pipeline needs to be replaced as a whole, resulting in high maintenance cost.

[0006] Single function: the connection method is usually simple sleeve connection or adhesive connection, which cannot be used as flange, and additional connection parts are needed. INVENTION CONTENTS

[0007] The utility model aims to provide a kind of flame-retardant power cable protection pipe to solve the problems raised in the above background technology.

[0008] To achieve the above purpose, the utility model provides the following technical scheme: a kind of flame-retardant power cable protection pipe, including modified polypropylene pipe, the outer side of the modified polypropylene pipe is sleeved with chlorinated polyvinyl chloride pipe, the end of modified polypropylene pipe and chlorinated polyvinyl chloride pipe is equipped with connecting ring, the surface of connecting ring is provided with bolt hole, and the surface of connecting ring is provided with two groups of screws, two groups of screws are respectively screwed in the end of modified polypropylene pipe and chlorinated polyvinyl chloride pipe after penetrating connecting ring.

[0009] Preferably, the modified polypropylene pipe and the chlorinated polyvinyl chloride pipe are equal in length, the outer wall of the modified polypropylene pipe is integrally formed with a plurality of modified polypropylene bars, the modified polypropylene bars are arc strips, the length of the modified polypropylene bars is less than the length of the modified polypropylene pipe, and the outer ring surface of the modified polypropylene bars abuts against the inner ring surface of the chlorinated polyvinyl chloride pipe.

[0010] Preferably, the connecting ring is a circular plate with a "T" shaped cross section, one end of the connecting ring is inserted between the modified polypropylene pipe and the chlorinated polyvinyl chloride pipe, the outer diameter of the other end of the connecting ring is greater than the outer diameter of the chlorinated polyvinyl chloride pipe, the bolt holes are multiple, and the multiple bolt holes are arranged and distributed equidistantly and equally along the outer edge of the connecting ring.

[0011] Preferably, the connecting ring extends into one end between the modified polypropylene pipe and the chlorinated polyvinyl chloride pipe, and the inner and outer ring faces are respectively provided with clamping grooves one and two, the clamping grooves one and two are both circular grooves, the outer wall of the modified polypropylene pipe is provided with a fixed elastic sealing ring one, the inner wall of the chlorinated polyvinyl chloride pipe is provided with a fixed elastic sealing ring two, after the connecting ring is inserted into the modified polypropylene pipe and the chlorinated polyvinyl chloride pipe, the elastic sealing ring one is inserted into the clamping groove one, and the elastic sealing ring two is inserted into the clamping groove two.

[0012] Preferably, the surface of the connecting ring is provided with a plurality of reserved holes one, the reserved holes one are "convex" circular holes, the screws and the reserved holes one are one-to-one corresponding, and the screws are screwed on the end portion of the chlorinated polyvinyl chloride pipe after penetrating through the reserved holes one.

[0013] Preferably, the surface of the connecting ring is provided with a plurality of reserved holes two, the reserved holes two are "convex" circular holes, the screws and the reserved holes two are one-to-one corresponding, and the screws are screwed on the end portion of the modified polypropylene pipe after penetrating through the reserved holes two.

[0014] Compared with the prior art, the utility model has the advantages that:

[0015] The fire -retardant power cable protection pipe provided by the utility model is composed of a double -layer pipeline formed by a modified polypropylene pipe and a chlorinated polyvinyl chloride pipe, the fire -retardant effect is improved, and the compression effect is improved, the connecting ring is used, the modified polypropylene pipe and the chlorinated polyvinyl chloride pipe are connected, and the adjacent two groups of protection pipes are connected, the fire -retardant power cable protection pipe is innovated by double -layer composite material and connecting ring design, the problems of poor fire -retardant performance, insufficient compression strength, high maintenance cost and other problems of single -layer pipeline are solved, has significant technical advantage and market competitiveness, and is suitable for high -voltage, high -load, complex construction environment's power transmission system. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 It is the structure schematic view of the utility model;

[0017] Figure 2 It is the structure side view of the utility model;

[0018] Figure 3 It is Figure 2 It is the structure cross section schematic view of A-A in the utility model;

[0019] Figure 4 It is Figure 3 It is the enlarged structure schematic view of A in the utility model;

[0020] Figure 5 It is the connecting ring structure schematic view of the utility model;

[0021] Figure 6This is a schematic diagram of the connection structure between the modified polypropylene pipe and the modified polypropylene support strip of this utility model.

[0022] In the diagram: 1. Modified polypropylene pipe; 2. Chlorinated polyvinyl chloride pipe; 3. Connecting ring; 4. Bolt hole; 5. Reserved hole one; 6. Reserved hole two; 7. Screw; 8. Slot one; 9. Slot two; 10. Elastic sealing ring one; 11. Elastic sealing ring two; 12. Modified polypropylene support strip. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of this utility model clear and complete, the embodiments of this utility model will be further described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only some, not all, embodiments of this utility model, and are merely used to explain the embodiments of this utility model. They are not intended to limit 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.

[0024] Please see Figures 1-5This utility model provides a technical solution: a flame-retardant power cable protection pipe, comprising a modified polypropylene pipe 1, with a chlorinated polyvinyl chloride pipe 2 sleeved on the outer side of the modified polypropylene pipe 1. The modified polypropylene pipe 1 and the chlorinated polyvinyl chloride pipe 2 are of equal length. Multiple modified polypropylene support strips 12 are integrally formed on the outer wall of the modified polypropylene pipe 1. The modified polypropylene support strips 12 are arc-shaped, and their plate length is less than the pipe length of the modified polypropylene pipe 1. The outer ring surface of the modified polypropylene support strips 12 rests against the inner ring surface of the chlorinated polyvinyl chloride pipe 2. Both the modified polypropylene pipe 1 and the chlorinated polyvinyl chloride pipe 2 have connecting rings 3 at their ends. Bolt holes 4 are formed on the surface of the connecting rings 3. The connecting rings 3 are circular plates with a "T"-shaped cross-section. One end of the connecting ring 3 is inserted between the modified polypropylene pipe 1 and the chlorinated polyvinyl chloride pipe 2, and the outer diameter of the other end of the connecting ring 3 is larger than the outer diameter of the chlorinated polyvinyl chloride pipe 2. Multiple bolt holes 4 are provided, and the multiple bolt holes 4 are distributed at equal intervals and of equal size along the outer edge of the connecting ring 3. The system employs a double-layer pipe structure consisting of modified polypropylene pipe 1 and chlorinated polyvinyl chloride pipe 2. Modified polypropylene pipe 1 is heat-resistant, corrosion-resistant, and flexible, while chlorinated polyvinyl chloride pipe 2 boasts high strength, high temperature resistance, and excellent flame retardancy, with a Vicat softening point exceeding 93℃. This double-layer structure not only provides excellent flame retardancy but also enhances protection. Even if the surface of chlorinated polyvinyl chloride pipe 2 is damaged, modified polypropylene pipe 1 still effectively protects the internal cables. Furthermore, damaged modified polypropylene pipe 1 or chlorinated polyvinyl chloride pipe 2 can be replaced individually, avoiding the high cost of replacing the entire pipeline. A connecting ring 3 is installed between modified polypropylene pipe 1 and chlorinated polyvinyl chloride pipe 2, not only connecting the two pipes but also serving as a flange for connecting adjacent sets of protective pipes. Thus, the connecting ring 3 is a dual-purpose device with multiple functions.

[0025] The table below compares the flame-retardant effect and compressive strength of single-layer flame-retardant power cable protection pipes and double-layer protection pipes (chlorinated polyvinyl chloride pipe + modified polypropylene):

[0026]

[0027] The double-layer protective tube has superior flame retardant properties. The outer CPVC layer provides flame retardancy and self-extinguishing properties, while the inner MPP layer is non-combustible and can prevent the spread of flames. It also has higher overall light transmittance and less smoke during combustion.

[0028] The compressive strength comparison is shown in the table below:

[0029]

[0030] The compressive strength of double-layer protective pipes is significantly higher than that of single-layer protective pipes. The addition of the inner MPP layer greatly improves the overall compressive strength, making it suitable for more complex construction environments.

[0031] One end of the connecting ring 3, which extends between the modified polypropylene pipe 1 and the chlorinated polyvinyl chloride pipe 2, has a groove 8 on the inner ring surface and a groove 9 on the outer ring surface. Both groove 8 and groove 9 are circular grooves. An elastic sealing ring 10 is fixedly fitted on the outer wall of the modified polypropylene pipe 1, and an elastic sealing ring 11 is fixed on the inner wall of the chlorinated polyvinyl chloride pipe 2. After one end of the connecting ring 3 is inserted between the modified polypropylene pipe 1 and the chlorinated polyvinyl chloride pipe 2, the elastic sealing ring 10 is inserted into groove 8, and the elastic sealing ring 11 is inserted into groove 9. At this time, the end of the connecting ring 3 is supported between the grooves of the modified polypropylene pipe 1 and the chlorinated polyvinyl chloride pipe 2 to prevent the grooves from being damaged by pressure. The elastic sealing ring 10 is inserted into the slot 8 and the elastic sealing ring 11 is inserted into the slot 9, which improves the sealing performance after the modified polypropylene pipe 1 and the chlorinated polyvinyl chloride pipe 2 are connected. Furthermore, the elastic sealing ring 11 and the elastic sealing ring 10 increase the friction between the connecting ring 3 and the modified polypropylene pipe 1 and the chlorinated polyvinyl chloride pipe 2, preventing the connecting ring 3 from being pulled out from between the modified polypropylene pipe 1 and the chlorinated polyvinyl chloride pipe 2 at will.

[0032] The surface of the connecting ring 3 is provided with two sets of screws 7. The two sets of screws 7 pass through the connecting ring 3 and are screwed to the ends of the modified polypropylene tube 1 and the chlorinated polyvinyl chloride tube 2 respectively. The surface of the connecting ring 3 is provided with multiple pre-drilled holes 1 5. The pre-drilled holes 1 5 are convex-shaped round holes. The screws 7 correspond one-to-one with the pre-drilled holes 1 5. The screws 7 pass through the pre-drilled holes 1 5 and are screwed to the ends of the chlorinated polyvinyl chloride tube 2. The surface of the connecting ring 3 is provided with multiple pre-drilled holes 2 6. The pre-drilled holes 2 6 are convex-shaped round holes. The screws 7 correspond one-to-one with the pre-drilled holes 2 6. The screws 7 pass through the pre-drilled holes 2 6 and are screwed to the ends of the modified polypropylene tube 1. The connecting ring 3 is fixed to the ends of the modified polypropylene pipe 1 and the chlorinated polyvinyl chloride pipe 2 using screws 7. This facilitates the individual replacement of the modified polypropylene pipe 1 and the chlorinated polyvinyl chloride pipe 2 later. That is, after the connecting ring 3 is removed from the ends of the modified polypropylene pipe 1 and the chlorinated polyvinyl chloride pipe 2, the damaged modified polypropylene pipe 1 or the chlorinated polyvinyl chloride pipe 2 can be removed and replaced with a new one. When assembling the two sets of protective pipes end to end, the bolts are passed through the screws 7 on the surfaces of the two adjacent connecting rings 3 and then tightened.

[0033] Instructions for using flame-retardant power cable protection pipe (double-layer structure): Insert one end of the connecting ring 3 between the modified polypropylene pipe 1 and the chlorinated polyvinyl chloride pipe 2, ensuring that: the elastic sealing ring 10 is fully embedded in the groove 8, and the elastic sealing ring 11 is fully embedded in the groove 9. Confirm that the end of the connecting ring 3 is supported between the grooves of the modified polypropylene pipe 1 and the chlorinated polyvinyl chloride pipe 2 to prevent the grooves from being damaged by pressure. Use a screwdriver to thread the screw 7 through the pre-drilled hole 5 and screw it onto the end of the chlorinated polyvinyl chloride pipe 2. Use a screwdriver to thread the screw 7 through the pre-drilled hole 6 and screw it onto the end of the modified polypropylene pipe 1. Ensure that the screw 7 is evenly stressed to prevent the connecting ring 3 from loosening. Align the connecting rings 3 of the two protection pipes, and tighten them by passing bolts through the bolt holes 4 on the surfaces of the two adjacent connecting rings 3. Ensure that the bolts are tight, the pipe connection is secure, and there is no loosening or leakage. Bury the assembled pipe underground, ensuring that the burial depth meets the design requirements (e.g., greater than 4m). In bridge, tunnel, and other scenarios, trenchless technology can be used to traverse obstacles. Install the pipes on the cable tray, ensuring uniform spacing for easy heat dissipation and maintenance. For repairs: Remove screws 7 and bolts from connecting ring 3. Remove the damaged modified polypropylene pipe 1 or chlorinated polyvinyl chloride pipe 2. Install new pipes and reassemble connecting ring 3. If connecting ring 3 is damaged: Replace with a new connecting ring 3, ensuring a tight seal and strong connection.

[0034] This flame-retardant power cable protection pipe adopts a double-layer structure design, with an outer layer of chlorinated polyvinyl chloride (CPVC) and an inner layer of modified polypropylene (MPP), achieving a stable connection through connecting ring 3. This design offers the following advantages:

[0035] Excellent flame retardant performance: The outer layer of CPVC has a high flame retardant rating, while the inner layer of MPP is non-combustible, resulting in a significant improvement in overall flame retardant effect.

[0036] High compressive strength: The inner MPP layer has a compressive strength of 30-40MPa, and the outer CPVC layer works synergistically with the inner layer to achieve a ring stiffness of 40-50kPa.

[0037] Easy maintenance: The inner or outer layer of pipes can be replaced individually, reducing maintenance costs.

[0038] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A flame-retardant power cable protection pipe, comprising a modified polypropylene pipe (1), characterized in that: A chlorinated polyvinyl chloride pipe (2) is sleeved outside the modified polypropylene pipe (1). Connection rings (3) are provided at the ends of both the modified polypropylene pipe (1) and the chlorinated polyvinyl chloride pipe (2). Bolt holes (4) are formed on the surface of the connection ring (3), and two groups of screws (7) are provided on the surface of the connection ring (3). After the two groups of screws (7) penetrate through the connection ring (3), they are respectively screwed to the ends of the modified polypropylene pipe (1) and the chlorinated polyvinyl chloride pipe (2).

2. The flame-retardant power cable protection pipe according to claim 1, characterized in that: The modified polypropylene pipe (1) and the chlorinated polyvinyl chloride pipe (2) are of the same length. A plurality of modified polypropylene braces (12) are integrally formed on the outer wall of the modified polypropylene pipe (1). The modified polypropylene braces (12) are in the shape of arc bars. The plate length of the modified polypropylene braces (12) is less than the pipe length of the modified polypropylene pipe (1). The outer ring surface of the modified polypropylene braces (12) abuts against the inner ring surface of the chlorinated polyvinyl chloride pipe (2).

3. The flame-retardant power cable protection pipe according to claim 1, characterized in that: The connection ring (3) is in the shape of a circular ring plate with a "T" - shaped cross - section. One end of the connection ring (3) is inserted between the modified polypropylene pipe (1) and the chlorinated polyvinyl chloride pipe (2). The outer diameter of the other end of the connection ring (3) is greater than the outer diameter of the chlorinated polyvinyl chloride pipe (2). A plurality of bolt holes (4) are provided, and the plurality of bolt holes (4) are arranged equidistantly and with the same size along the outer edge of the connection ring (3).

4. The flame-retardant power cable protection pipe according to claim 1, characterized in that: One end of the connection ring (3) extending between the modified polypropylene pipe (1) and the chlorinated polyvinyl chloride pipe (2) is provided with a first clamping groove (8) and a second clamping groove (9) on the inner ring surface and the outer ring surface respectively. Both the first clamping groove (8) and the second clamping groove (9) are in the shape of circular ring grooves. An elastic sealing ring one (10) is sleeved and fixed on the outer wall of the modified polypropylene pipe (1), and an elastic sealing ring two (11) is fixed on the inner wall of the chlorinated polyvinyl chloride pipe (2). After one end of the connection ring (3) is inserted between the modified polypropylene pipe (1) and the chlorinated polyvinyl chloride pipe (2), the elastic sealing ring one (10) is stuffed into the first clamping groove (8), and the elastic sealing ring two (11) is stuffed into the second clamping groove (9).

5. The flame-retardant power cable protection pipe according to claim 1, characterized in that: A plurality of first reserved holes (5) are formed on the surface of the connection ring (3). The first reserved holes (5) are in the shape of "convex" - shaped round holes. The screws (7) and the first reserved holes (5) correspond to each other. After the screws (7) penetrate through the first reserved holes (5), they are screwed to the end of the chlorinated polyvinyl chloride pipe (2).

6. The flame-retardant power cable protection pipe according to claim 1, characterized in that: A plurality of second reserved holes (6) are formed on the surface of the connection ring (3). The second reserved holes (6) are in the shape of "convex" - shaped round holes. The screws (7) and the second reserved holes (6) correspond to each other. After the screws (7) penetrate through the second reserved holes (6), they are screwed to the end of the modified polypropylene pipe (1).

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