A porous ceramic composite tube and a method of manufacturing the same

Abstract

The application discloses a kind of porous ceramic composite pipe and its manufacturing method, composite pipe includes ceramic inner core and polymer shell, the ceramic inner core is evenly provided with connecting hole and limiting hole, one end of polymer limiting block is inserted into limiting hole, the other end extends to polymer shell, polymer shell is inlayed with connecting hole and is connected, manufacturing process is prepared ceramic inner core in advance, then polymer limiting block is inserted into the limiting hole of ceramic inner core, and it is placed into mold fixed mold, polymer limiting block is in contact with mold fixed mold surface and is used to support ceramic inner core, after mold is closed, polymer limiting block is in contact with the whole cavity surface and is supported, then injection molding production is carried out, polymer material flows through the inner and outer surfaces of ceramic inner core and connecting hole, after polymer melt is cooled, the composite of ceramic inner core and polymer shell is completed.The application uses porous ceramic to make pipe inner core, and gives pipe more excellent heat preservation and noise reduction function.

Description

Technical Field

[0001] This invention belongs to the field of composite pipe technology, specifically relating to a porous ceramic composite pipe and its manufacturing method. Background Technology

[0002] A fresh air system mainly consists of a fresh air unit, a fresh air duct distribution system, and corresponding air outlets. As an important component of low-energy buildings / passive houses, fresh air systems have a promising market prospect in the context of building upgrades.

[0003] Passive houses / low-energy buildings have high requirements for protecting indoor temperature and humidity, and existing fresh air systems have also undergone some technological research in this regard. For example, by equipping the main unit with heating / auxiliary heating functions, when using the fresh air system in northern winters, if the indoor / outdoor temperature difference reaches 10 degrees Celsius or more, the main unit can preheat the fresh air introduced into the room, thereby reducing its impact on the indoor temperature.

[0004] Current research and industry understanding indicates that most temperature control improvements focus on upgrading the main unit, with very little (almost none) research on the fresh air delivery system. Considering the overall system, fresh air distribution systems are characterized by long ductwork, inevitably leading to energy loss. Therefore, improving the insulation performance of fresh air systems is a major research topic. Summary of the Invention

[0005] In view of the problems existing in the prior art, the purpose of this invention is to provide a porous ceramic composite pipe and its manufacturing method.

[0006] To achieve the above objectives, the following technical solution is proposed:

[0007] A porous ceramic composite tube includes a ceramic inner core and a polymer outer shell. The ceramic inner core is uniformly provided with connecting holes and limiting holes. One end of the polymer limiting block is inserted into the limiting hole, and the other end extends into the polymer outer shell. The polymer outer shell is fitted and connected to the connecting hole.

[0008] Furthermore, the outer circumference of the polymer limiting block is provided with a stepped structure extending horizontally outward. The stepped structure contacts the limiting hole to limit the polymer limiting block.

[0009] A method for manufacturing a porous ceramic composite pipe includes the following steps:

[0010] 1) Mix the dispersant ammonium polyacrylate, binder methylcellulose and solvent deionized water, adjust the pH to 10 and pour into a mixer and stir evenly. Then slowly add zirconium oxide powder and ball mill it using a planetary ball mill to obtain a high solid phase suspension.

[0011] 2) The high-solids suspension was diluted with deionized water, and the diluted suspension was mixed with sodium dodecyl sulfate in a mixer and then n-octane was added and stirred to obtain an intermediate material.

[0012] 3) Add hydrochloric acid to adjust the pH and induce gelation to complete the preparation of the slurry;

[0013] 4) Pour the slurry prepared in step 3) into a mold to form a preform and place it for more than 24 hours;

[0014] 5) Place the green body into a sintering furnace and heat it to 1350-1600℃ at a rate of 3℃ / min. Hold it at that temperature for 2-4 hours and then cool it to room temperature with the furnace to obtain a porous ceramic core (3).

[0015] 6) Insert the polymer limiting block into the limiting hole of the ceramic inner core and place it into the mold fixed mold. The polymer limiting block contacts the surface of the mold fixed mold and is used to support the ceramic inner core. After the mold is closed, the polymer limiting block contacts and supports the entire cavity surface. Then, injection molding is carried out. The polymer material flows through the inner and outer surfaces of the ceramic inner core and the connecting hole. After the polymer melt cools, the composite of the ceramic inner core and the polymer shell is completed.

[0016] Furthermore, in step 1), the amount of ammonium polyacrylate added is 0.5-1.5 wt% of the zirconium oxide powder.

[0017] Furthermore, in step 1), the amount of methylcellulose added is 0.16-0.2 wt% of the zirconium oxide powder.

[0018] Further, in step 2), the suspension is diluted with deionized water until the solid content is 40-48 wt%.

[0019] Further, in step 2), the amount of sodium dodecyl sulfate added is 0.5-2.0 wt% of the zirconium oxide powder, and the amount of n-octane added is 0.5-1 wt% of the zirconium oxide powder.

[0020] Furthermore, the concentration of hydrochloric acid in step 3) is 12 mol / L.

[0021] Further, in step 3), the amount of hydrochloric acid added is 0.25-0.65 vol of the diluted suspension.

[0022] Furthermore, the polymer shell (1) and the polymer limiting block (2) are made of the same material, namely HDPE or PPR.

[0023] The beneficial effects of this invention are as follows:

[0024] Combining the excellent properties of porous ceramics, such as low density, high specific strength, high thermal stability, low thermal conductivity, superior sound absorption, and corrosion resistance, this invention uses porous ceramics to make the inner core of the pipe fittings, giving the pipe fittings superior heat insulation and noise reduction functions. At the same time, due to the high specific strength of porous ceramics, the material has good thermal stability and corrosion resistance, and has a long service life under complex working conditions. Thus, the composite pipe as a whole has good stability, corrosion resistance, and noise reduction. The polymer on the surface of the composite pipe fitting and the pipe can be melted by heating. After the molten layer is cooled under a certain pressure, the connection can be achieved, making the pipe fitting and the pipe a whole. Compared with individual ceramic pipe fittings, this connection method of composite pipe fittings is not only easy to operate, but also can effectively ensure the sealing and strength of the connection. Attached Figure Description

[0025] Figure 1 This is a cross-sectional view of the composite tube of the present invention;

[0026] Figure 2 This is a front view of the polymer limiting block of the present invention;

[0027] Figure 3 This is a schematic diagram of the ceramic inner core of the present invention disposed in the mold fixed mold.

[0028] In the diagram: 1. Polymer outer shell; 2. Polymer limiting block; 3. Ceramic inner core; 301. Connecting hole; 302. Limiting hole. Detailed Implementation

[0029] The present invention will be further described below with reference to the accompanying drawings and embodiments, but the scope of protection of the present invention is not limited thereto.

[0030] like Figure 1 and Figure 3 As shown, a porous ceramic composite tube includes a ceramic inner core 3 and a polymer outer shell 1. The ceramic inner core 3 has uniformly formed connecting holes 301 and limiting holes 302. One end of a polymer limiting block 2 is inserted into the limiting hole 302, and the other end extends into the polymer outer shell 1. The polymer outer shell 1 is fitted and connected to the connecting hole 301. Figure 2 As shown, the outer circumference of the polymer limiting block 2 is provided with a horizontally extending stepped structure. The stepped structure contacts the limiting hole 302 to limit the polymer limiting block 2. The shape and structure of the polymer limiting block 2 are not limited to... Figure 2 As shown, any structure that can achieve the limit support is acceptable.

[0031] Example 1

[0032] A method for manufacturing a porous ceramic composite pipe includes the following steps:

[0033] 1) Using zirconium oxide powder as the base, 0.5wt% ammonium polyacrylate, 0.17wt% methylcellulose and deionized water were mixed, the pH was adjusted to 10 and then poured into a mixer and stirred evenly. Then, zirconium oxide powder was slowly added and ball milled using a planetary ball mill to obtain a high solid suspension with a solid content of 50wt%.

[0034] 2) Dilute the suspension to 40 wt% with deionized water, add 1.5 wt% sodium dodecyl sulfate to the suspension and mix in a mixer, then add 1 wt% n-octane and stir to obtain an emulsion / foam;

[0035] 3) Using the diluted suspension as a reference, add 0.4 vol% hydrochloric acid to adjust the pH and induce gelation to complete the preparation of the slurry;

[0036] 4) Pour the slurry prepared in step 3) into a mold to form a preform and place it for 24 hours;

[0037] 5) Place the green body into a sintering furnace, heat it to 1500℃ at a rate of 3℃ / min, hold it for 2 hours, and cool it to room temperature with the furnace to obtain a porous ceramic core 3.

[0038] 6) The polymer limiting block 2 and the polymer shell 1 are made of HDPE. The polymer limiting block 2 is inserted into the limiting hole 302 of the ceramic inner core 3 and placed in the mold. The polymer limiting block 2 contacts the surface of the mold and is used to support the ceramic inner core 3. After the mold is closed, the polymer limiting block 2 contacts and supports the entire cavity surface. Then, injection molding is carried out. The polymer material flows through the inner and outer surfaces of the ceramic inner core 3 and the connecting hole 301. After the polymer melt cools, the composite of the ceramic inner core 3 and the polymer shell 1 is completed.

[0039] Tests showed that the thermal conductivity of the composite pipe fittings was 0.21 W / (m·K), while that of conventional PE pipe fittings was 0.42 W / (m·K), indicating a significant improvement in insulation performance. Meanwhile, the ceramic core 3 has a porosity of 33.5%, with a relatively small pore size range, mainly concentrated in the range of 0.68~2 μm. According to Huygens' principle, sound wave energy will be dissipated in these pores, achieving a noise reduction effect.

[0040] Example 2

[0041] 1) Using zirconium oxide powder as the base, 0.5wt% ammonium polyacrylate, 0.17wt% methylcellulose and deionized water were mixed, the pH was adjusted to 10 and then poured into a mixer and stirred evenly. Then, zirconium oxide powder was slowly added and ball milled using a planetary ball mill to obtain a high solid suspension with a solid content of 50wt%.

[0042] 2) Dilute the suspension to 48 wt% with deionized water, add 1.5 wt% sodium dodecyl sulfate to the suspension and mix in a mixer, then add 1 wt% n-octane and stir to obtain an emulsion / foam;

[0043] 3) Using the diluted suspension as a reference, add 0.4 vol% hydrochloric acid to adjust the pH and induce gelation to complete the preparation of the slurry;

[0044] 4) Pour the slurry prepared in step 3) into a mold to form a preform and place it for 24 hours;

[0045] 5) Place the green body into a sintering furnace, heat it to 1500℃ at a rate of 3℃ / min, hold it for 2 hours, and cool it to room temperature with the furnace to obtain a porous ceramic core 3.

[0046] 6) The polymer limiting block 2 and the polymer shell 1 are made of HDPE. The polymer limiting block 2 is inserted into the limiting hole 302 of the ceramic inner core 3 and placed in the mold. The polymer limiting block 2 contacts the surface of the mold and is used to support the ceramic inner core 3. After the mold is closed, the polymer limiting block 2 contacts and supports the entire cavity surface. Then, injection molding is carried out. The polymer material flows through the inner and outer surfaces of the ceramic inner core 3 and the connecting hole 301. After the polymer melt cools, the composite of the ceramic inner core 3 and the polymer shell 1 is completed.

[0047] Tests showed that the thermal conductivity of the composite pipe fittings was 0.24 W / (m·K), while that of conventional PE pipe fittings was 0.42 W / (m·K), indicating a significant improvement in insulation performance. Meanwhile, the ceramic core 3 has a porosity of 32.8%, with a relatively small pore size range, mainly concentrated in the range of 0.68~2 μm. According to Huygens' principle, sound wave energy will be dissipated in these pores, achieving a noise reduction effect.

[0048] Example 3

[0049] 1) Using zirconium oxide powder as the base, 0.5wt% ammonium polyacrylate, 0.17wt% methylcellulose and deionized water were mixed, the pH was adjusted to 10 and then poured into a mixer and stirred evenly. Then, zirconium oxide powder was slowly added and ball milled using a planetary ball mill to obtain a high solid suspension with a solid content of 50wt%.

[0050] 2) Dilute the suspension to 48 wt% with deionized water, add 1.5 wt% sodium dodecyl sulfate to the suspension and mix in a mixer, then add 1 wt% n-octane and stir to obtain an emulsion / foam;

[0051] 3) Using the diluted suspension as a reference, add 0.4 vol% hydrochloric acid to adjust the pH and induce gelation to complete the preparation of the slurry;

[0052] 4) Pour the slurry prepared in step 3) into a mold to form a preform and place it for 24 hours;

[0053] 5) Place the green body into a sintering furnace, heat it to 1400℃ at a rate of 3℃ / min, hold it for 2 hours, and cool it to room temperature with the furnace to obtain a porous ceramic core 3;

[0054] 6) The polymer limiting block 2 and the polymer shell 1 are made of HDPE. The polymer limiting block 2 is inserted into the limiting hole 302 of the ceramic inner core 3 and placed in the mold. The polymer limiting block 2 contacts the surface of the mold and is used to support the ceramic inner core 3. After the mold is closed, the polymer limiting block 2 contacts and supports the entire cavity surface. Then, injection molding is carried out. The polymer material flows through the inner and outer surfaces of the ceramic inner core 3 and the connecting hole 301. After the polymer melt cools, the composite of the ceramic inner core 3 and the polymer shell 1 is completed.

[0055] Tests showed that the thermal conductivity of the composite pipe fittings was 0.25 W / (m·K), while that of conventional PE pipe fittings was 0.42 W / (m·K), indicating a significant improvement in thermal insulation performance. Meanwhile, the ceramic core 3 has a porosity of 29.3%, with a relatively small pore size range, mainly concentrated in the range of 0.68~2 μm. According to Huygens' principle, sound wave energy will be dissipated in these pores, achieving a noise reduction effect.

Claims

1. A porous ceramic composite pipe, characterized in that... It includes a ceramic inner core (3) and a polymer outer shell (1). The ceramic inner core (3) is uniformly provided with a connecting hole (301) and a limiting hole (302). One end of the polymer limiting block (2) is inserted into the limiting hole (302), and the other end extends into the polymer outer shell (1). The polymer outer shell (1) is fitted and connected with the connecting hole (301). The outer circumference of the polymer limiting block (2) is provided with a stepped structure extending outward horizontally. The stepped structure contacts the limiting hole (302) to limit the polymer limiting block (2). The manufacturing method of porous ceramic composite pipe includes the following steps: 1) Mix the dispersant ammonium polyacrylate, binder methylcellulose and solvent deionized water, adjust the pH to 10 and pour into a mixer and stir evenly. Then slowly add zirconium oxide powder and ball mill it using a planetary ball mill to obtain a high solid phase suspension. 2) The high-solids suspension was diluted with deionized water, and the diluted suspension was mixed with sodium dodecyl sulfate in a mixer and then n-octane was added and stirred to obtain an intermediate material. 3) Add hydrochloric acid to adjust the pH and induce gelation to complete the preparation of the slurry; 4) Pour the slurry prepared in step 3) into a mold to form a preform and place it for more than 24 hours; 5) Place the green body into a sintering furnace and heat it to 1350-1600℃ at a rate of 3℃ / min. Hold it at that temperature for 2-4 hours and then cool it to room temperature with the furnace to obtain a porous ceramic core (3). 6) Insert the polymer limiting block (2) into the limiting hole (302) of the ceramic inner core (3) and place it in the mold fixed mold. The polymer limiting block (2) contacts the mold fixed mold surface and is used to support the ceramic inner core (3). After the mold is closed, the polymer limiting block (2) contacts and supports the entire cavity surface. Then, injection molding is carried out. The polymer material flows through the inner and outer surfaces of the ceramic inner core (3) and the connecting hole (301). After the polymer melt cools down, the composite of the ceramic inner core (3) and the polymer shell (1) is completed.

2. The porous ceramic composite tube as described in claim 1, characterized in that... In step 1), the amount of ammonium polyacrylate added is 0.5-1.5 wt% of the zirconium oxide powder.

3. A porous ceramic composite tube as described in claim 1, characterized in that... In step 1), the amount of methylcellulose added is 0.16-0.2 wt% of the zirconium oxide powder.

4. A porous ceramic composite tube as described in claim 1, characterized in that... In step 2), the suspension is diluted with deionized water until the solid content is 40-48 wt%.

5. The porous ceramic composite tube as described in claim 1, characterized in that... In step 2), the amount of sodium dodecyl sulfate added is 0.5-2.0 wt% of the zirconium oxide powder, and the amount of n-octane added is 0.5-1 wt% of the zirconium oxide powder.

6. A porous ceramic composite tube as described in claim 1, characterized in that... The concentration of hydrochloric acid in step 3) is 12 mol / L.

7. A porous ceramic composite tube as described in claim 1, characterized in that... In step 3), the amount of hydrochloric acid added is 0.25-0.65 vol of the diluted suspension.

8. A porous ceramic composite tube as described in claim 1, characterized in that... The polymer shell (1) and the polymer limiting block (2) are made of the same material, namely HDPE or PPR.

Images