Frost crack resistant PE pipe

Abstract

The utility model relates to an anti-frost crack PE pipe, the outer wall of the PE pipe is coated with a paraffin PCM coating, the paraffin PCM coating is hermetically bonded with an aluminum foil reflecting layer through an epoxy-polyurethane bonding layer, the PE pipe is further sleeved with a heat preservation sleeve, the heat preservation sleeve is formed by splicing two half casing pipes, each half casing pipe comprises an inner casing pipe and an outer casing pipe, one ends of the inner sleeve and the outer sleeve on the same side are equal in length and are hermetically connected through an arc-shaped part, the other end of the inner sleeve is longer than the other end of the outer sleeve, an outer thread is formed on the longer part of the inner sleeve, an inner conical surface is formed on the inner wall of the end part, corresponding to the outer thread, of the outer sleeve, and a heat preservation cavity is formed between the outer sleeve and the inner sleeve; the heat preservation cavity is filled with an aerogel heat preservation layer, and the inner sleeve of the two half sleeves is in threaded connection with a conical threaded sleeve. The paraffin PCM coating can be matched with the aluminum foil reflecting layer to achieve solidification heat release at low temperature, temperature fluctuation of the PE pipe can be adjusted, heat preservation is conducted in cooperation with the heat preservation sleeve wrapped outside, and the frost crack risk of the pipeline can be effectively reduced.

Description

Technical Field

[0001] This utility model relates to the field of PE pipe technology, specifically to a PE pipe resistant to freezing and cracking. Background Technology

[0002] Currently, PE pipes are widely used in water supply and drainage projects due to their good corrosion resistance and ease of construction. PE pipes are made of polyethylene material through extrusion or blow molding. Although PE pipes have advantages such as corrosion resistance, lightweight construction, and ease of installation, they also have disadvantages such as low compressive strength, easy aging, susceptibility to bursting at low temperatures, and poor toughness.

[0003] PE pipes are susceptible to freezing and cracking in cold weather. To prevent this, preventative measures are needed to ensure the integrity and function of the pipeline system. Current technology primarily involves wrapping the PE pipe with insulation material to prevent freezing and cracking in cold environments. However, this wrapping method, which involves spiraling, is time-consuming and difficult to disassemble. The removed insulation layer is essentially unusable, and replacement or repair is inconvenient after partial damage. Utility Model Content

[0004] To address the shortcomings of existing technologies, this invention provides a PE pipe resistant to freezing and cracking. By utilizing the phase change characteristics of the paraffin PCM coating, it can release heat through phase change according to temperature changes to regulate the temperature fluctuation of the PE pipe. The aerogel insulation layer inside the insulation jacket can effectively isolate the pipe from the external temperature exchange, thereby effectively reducing the risk of pipe freezing and cracking and improving the pipe's antifreeze performance.

[0005] This utility model is achieved through the following technical solution:

[0006] A frost-resistant PE pipe is provided. The outer wall of the PE pipe is coated with a paraffin PCM coating, and an aluminum foil reflective layer is sealed and bonded to the paraffin PCM coating by an epoxy-polyurethane adhesive layer. The PE pipe is also covered with an insulation sleeve, which is formed by splicing two half-sleeves. Each half-sleeve includes an inner sleeve and an outer sleeve. The inner sleeve and the outer sleeve are of equal length at one end on the same side and are sealed and connected by an arc-shaped part. The other end of the inner sleeve is longer than the other end of the outer sleeve, and the extended part of the inner sleeve has an external thread. The inner wall of the end of the outer sleeve corresponding to the external thread has an inner conical surface. An insulation cavity is formed between the outer sleeve and the inner sleeve, and the insulation cavity is filled with an aerogel insulation layer. The inner sleeves of the two half-sleeves are threaded with conical threaded sleeves for sealing the insulation cavity and fixing the two half-sleeves together.

[0007] Furthermore, the ends of the two half-sleeves are connected by a tapered threaded sleeve with internal threads on the inner wall. The tapered threaded sleeve includes an integrally formed tapered sleeve and a cylindrical sleeve. The tapered sleeve has an outer tapered surface that matches the inner tapered surface of the outer sleeve end. The inner diameter of the cylindrical sleeve is the same as the outer diameter of the inner sleeve, and the inner wall of the cylindrical sleeve is provided with an internal thread that matches the external thread on the inner sleeve.

[0008] By threading a tapered sleeve between the ends of the two half-sleeves, the cylindrical sleeve of the tapered sleeve can be used to lock the inner sleeve ends of the two half-sleeves to the PE pipe, so that the connection between the spliced ​​half-sleeves and the PE pipe can remain stable.

[0009] Furthermore, the PE pipe is also reinforced with glass fiber reinforcing tape that is spirally wound along the radial direction of the pipe by adhesive bonding outside the aluminum foil reflective layer.

[0010] The aluminum foil reflective layer is fixed by spirally winding a glass fiber reinforced shell along the radial direction of the pipe, which can also increase the tensile strength of the pipe to more than 200 MPa.

[0011] Furthermore, the glass fiber reinforced belt is coated with a polyurethane anti-corrosion coating.

[0012] Applying a polyurethane anti-corrosion coating to the outside of the glass limiting reinforcement strip can improve the surface's anti-corrosion and corrosion resistance, thereby enhancing the overall stability of the pipeline.

[0013] As a preferred option, clamps are also provided at intervals between the two half-sleeves.

[0014] By using clamps at intervals, the two half-sleeves can be effectively fixed to ensure the stability of the connection between the half-sleeves and the PE pipe.

[0015] Furthermore, the two half-sleeves have the same cross-sectional size and are both semi-circular. After the two half-sleeves are spliced ​​together, the inner sleeve is spliced ​​together to form a circular sleeve that surrounds and wraps around the outside of the PE pipe.

[0016] Both half-sleeves are semi-circular sleeves of the same size, which makes it easy to splice them and wrap them around the outside of the PE pipe to achieve the function of heat preservation and protection for the PE pipe.

[0017] The beneficial effects of this utility model are:

[0018] In this invention, a paraffin-coated PCM layer is sprayed onto the outer wall of the PE pipe, and an aluminum foil reflective layer is used to seal the PCM coating. This allows the PCM coating to regulate the temperature fluctuations of the PE pipe through phase change heating when the external temperature decreases. A spirally arranged glass fiber reinforcement band is bonded and fixed to the outside of the aluminum foil reflective layer to enhance the tensile strength of the PE pipe and ensure its stability. The PCM paraffin coating has a high melt-recycling rate, and the aluminum foil reflective layer can also be recycled separately. Both can be recycled and reused after pipe damage, resulting in good environmental performance.

[0019] This utility model utilizes two half-sleeves spliced ​​together and locked onto a PE pipe with a tapered screw sleeve. The insulation cavity of the half-sleeve is filled with an aerogel insulation layer, which can replace the traditional multi-layer insulation structure and effectively insulate the PE pipe. At the same time, the insulation cavity can be opened through the tapered screw sleeve to replenish it, and the half-sleeve is also easy to disassemble. The operation is convenient and easy, and the insulation device will not be damaged during disassembly. After disassembly, it can be reused for the next installation.

[0020] This invention reduces heat exchange between the pipeline and the external environment, while improving the tensile strength and stability of the pipeline, effectively preventing PE pipes from freezing and cracking in cold environments. Attached Figure Description

[0021] Figure 1 This is a cross-sectional schematic diagram of the PE pipe in this utility model.

[0022] Figure 2 This is a schematic diagram of the structure of the half-sleeve in this utility model.

[0023] Figure 3 This is a cross-sectional schematic diagram of the tapered threaded sleeve in this utility model.

[0024] Figure 4 This is a schematic diagram of the assembly structure in this utility model.

[0025] As shown in the figure:

[0026] 1. PE pipe, 2. Paraffin PCM coating, 3. Aluminum foil reflective layer, 4. Fiberglass reinforcing tape, 5. Inner sleeve, 6. Outer sleeve, 7. Aerogel insulation layer, 8. Half sleeve, 9. Insulation cavity, 10. Inner conical surface, 11. External thread, 12. Tapered threaded sleeve, 13. Conical sleeve, 14. Cylindrical sleeve, 15. Outer conical surface, 16. Internal thread. Detailed Implementation

[0027] To clearly illustrate the technical features of this solution, the following detailed implementation method will be used to explain the solution.

[0028] like Figures 1-4 As shown, a frost-resistant PE pipe has a paraffin PCM coating 2 on its outer wall, and an aluminum foil reflective layer 3 is sealed and bonded to the paraffin PCM coating 2 by an epoxy-polyurethane adhesive layer. A glass fiber reinforcing tape 4, spirally wound radially along the pipe, is also glued to the outside of the aluminum foil reflective layer 3. The glass fiber reinforcing tape 4 is coated with a polyurethane anti-corrosion coating.

[0029] Before applying the paraffin PCM coating 2, the PE pipe 1 undergoes surface treatment. This involves activating the surface of the PE pipe 1 using a plasma treatment machine (500W power, 30s) to increase the surface energy to 70mN / m, or applying an epoxy-polyurethane composite adhesive (0.1mm thickness, 15min curing time). Alternatively, the pipe can be immersed in a molten paraffin bath (temperature controlled ±1℃) at a pulling speed of 0.5m / min, repeated 2-3 times to complete the coating application. Then, rapid cooling (water or air cooling) is used to form a dense structure. Next, an aluminum foil reflective layer 3 is wrapped around the PE pipe, with a reflectivity ≥95%, to reduce heat loss. A continuous, sealed space must be formed between the aluminum foil and the PCM layer, and the overlap seams must be sealed three times. The overall compressive strength of the system must be ≥0.5MPa.

[0030] First, treat the surface of the paraffin PCM coating 2 by using a hot air gun (120℃) to soften the surface of the paraffin PCM coating 2 for 2-3 seconds / m. 2 Lay a 0.2mm polyester film temporary protective layer, cut the aluminum foil with a cutting machine, leave a 10% longitudinal overlap allowance, and mechanically press and fix it with a roller edge pressing machine. First, perform cold pressing to fix it, and then choose hot pressing to reinforce it as needed. The embossing depth is controlled between 0.1-0.3mm to enhance adhesion.

[0031] Primer treatment, followed by spraying polyurethane adhesive, coating amount: 0.15-0.2 g / m² 2 Curing time: 24 hours at room temperature / 1 hour at 80℃. Use aluminum foil-specific sealing tape (ASTM D3330 standard), overlap width ≥ 8mm, wrapping direction consistent with pipe axis, and seal with hot air welding gun (temperature 200℃, speed 1m / s).

[0032] The glass fiber reinforced tape is spirally wound at a winding angle of 55°±5°. Each layer is impregnated with an epoxy resin coating and cured in an oven at 80°C for 2 hours to ensure that the tensile strength of the PE pipe is ≥200Mpa.

[0033] The PE pipe 1 is also fitted with an insulation sleeve, which is formed by splicing two half-sleeves 8. Each half-sleeve 8 includes an inner sleeve 5 and an outer sleeve 6. The inner sleeve 5 and the outer sleeve 6 are of equal length at one end on the same side and are sealed and connected by an arc-shaped part. The other end of the inner sleeve 5 is longer than the other end of the outer sleeve 6, and the extended part of the inner sleeve 5 has an external thread 11. The inner wall of the end of the outer sleeve 6 corresponding to the external thread has an inner conical surface 10. An insulation cavity 9 is formed between the outer sleeve 6 and the inner sleeve 5, and an aerogel insulation layer 7 is filled in the insulation cavity 9. The inner sleeve 5 of the two half-sleeves 8 is threaded with a conical threaded sleeve 12 for sealing the insulation cavity 9 and for splicing and fixing the two half-sleeves 8.

[0034] The ends of the two half-sleeves 8 are connected by a tapered threaded sleeve 12 with internal threads on its inner wall. The tapered threaded sleeve 12 includes an integrally formed tapered sleeve 13 and a cylindrical sleeve 14. The tapered sleeve 14 has an outer tapered surface 15 that matches the inner tapered surface 10 at the end of the outer sleeve 6. The inner diameter of the cylindrical sleeve 14 is the same as the outer diameter of the inner sleeve 5, and the inner wall of the cylindrical sleeve 14 is provided with an internal thread 16 that matches the external thread 11 on the inner sleeve 5. The two half-sleeves 8 have the same cross-sectional size and are both semi-circular. After the two half-sleeves 8 are spliced ​​together, the inner sleeve 5 is spliced ​​to form a circular sleeve that surrounds and wraps around the outside of the PE pipe 1.

[0035] To ensure a tight connection between the half-sleeve 8 and the PE pipe 1, clamps are installed at intervals between the two half-sleeves 8 to tighten the connection between the half-sleeve 8 and the PE pipe 1, thereby improving stability.

[0036] In this invention, when installing the PE pipe 1, only an appropriate amount of aerogel insulation layer 7 needs to be added to the insulation cavity 9 of each of the two semi-circular half-sleeves 8. Then, the two half-sleeves 8 are wrapped around the outside of the PE pipe 1 to form a circular sleeve that surrounds the PE pipe 1. The two half-sleeves 8 are locked and fixed to the PE pipe 1 using a tapered screw sleeve 12. At the same time, the outer conical surface 15 at the end of the tapered screw sleeve 12 can enter the inner conical surface 10 at the end of the inner sleeve 5 and the outer sleeve 6 to seal the insulation cavity 9 and ensure that the aerogel insulation layer 7 does not leak out. When installing a long PE pipe 1, clamps can be set at intervals in the middle section to tighten it and ensure the stability of the connection between the half-sleeves 8 and the PE pipe 1. When the ambient temperature drops during use, the paraffin PCM coating 2 on the outer layer of PE pipe 1 undergoes a phase change and generates heat within the aluminum foil reflective layer 3. Combined with the reflective effect of the aluminum foil reflective layer 3, heat can be transferred to PE pipe 1, thereby reducing temperature fluctuations. At the same time, the aerogel insulation layer 7 in the insulation cavity 9 of the half-pipe 8 can also isolate PE pipe 1 from the outside environment, reducing heat transfer from PE pipe 1. The insulation effect is good, which can improve the antifreeze performance of PE pipe 1 and reduce the risk of freezing and cracking.

[0037] Of course, the above description is not limited to the examples above. Technical features not described in this utility model can be implemented by or using existing technology, and will not be repeated here. The above embodiments and drawings are only used to illustrate the technical solution of this utility model and are not intended to limit this utility model. This utility model has been described in detail with reference to preferred embodiments. Those skilled in the art should understand that any changes, modifications, additions or substitutions made by those skilled in the art within the scope of this utility model do not depart from the spirit of this utility model and should also fall within the protection scope of the claims of this utility model.

Claims

1. A freeze crack resistant PE pipe, characterized by: The outer wall of the PE pipe is coated with a paraffin PCM coating, and an aluminum foil reflective layer is sealed and bonded on the paraffin PCM coating through an epoxy-polyurethane bonding layer, and the PE pipe is further sleeved with a heat preservation sleeve, the heat preservation sleeve is formed by splicing two half sleeve pipes, each half sleeve pipe includes an inner sleeve pipe and an outer sleeve pipe, the inner sleeve pipe and the outer sleeve pipe are equal in length at the same side end and are sealingly connected through an arc-shaped part, the other end of the inner sleeve pipe is longer than the other end of the outer sleeve pipe, and the inner sleeve pipe is formed with external threads at the protruding part, the inner wall of the end portion of the outer sleeve pipe corresponding to the external threads is formed with an internal taper surface, a heat preservation cavity is formed between the outer sleeve pipe and the inner sleeve pipe, and the heat preservation cavity is filled with an aerogel heat preservation layer, and a conical sleeve for plugging the heat preservation cavity and splicing and fixing the two half sleeve pipes is threadedly connected to the inner sleeve pipe of the two half sleeve pipes.

2. The anti-cracking PE pipe according to claim 1, characterized in that: The end portions of the two half sleeve pipes are connected through the conical sleeve provided with internal threads on the inner wall, the conical sleeve includes an integrally formed conical sleeve and a cylindrical sleeve, the conical sleeve has an external taper surface matched with the internal taper surface of the end portion of the outer sleeve pipe, the inner diameter of the cylindrical sleeve is the same as the outer diameter of the inner sleeve pipe, and the inner wall of the cylindrical sleeve is provided with internal threads matched with the external threads on the inner sleeve pipe.

3. The freeze crack resistant PE pipe according to claim 1, characterized in that: The PE pipe is further fixed with a glass fiber reinforced belt spirally wound along the radial direction of the pipe through adhesion outside the aluminum foil reflective layer.

4. The anti-cracking PE pipe according to claim 3, characterized in that: The glass fiber reinforced belt is externally sprayed with a polyurethane corrosion-resistant coating.

5. The freeze crack resistant PE pipe according to claim 1, characterized in that: The two half sleeve pipes are further spaced apart with a hoop.

6. The freeze resistant PE pipe of claim 1, wherein: The cross sections of the two half sleeve pipes are the same and are semicircular, and the inner sleeve pipes are spliced to form a circular sleeve pipe wrapped around the outside of the PE pipe after the two half sleeve pipes are spliced.

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