阅读说明：本技术 一种聚丙烯管及其加工工艺 (Polypropylene pipe and processing technology thereof ) 是由 袁国栋 于 2021-08-10 设计创作，主要内容包括：本发明涉及聚丙烯管领域,更具体的说是一种聚丙烯管及其加工工艺,一种聚丙烯管加工工艺,该工艺包括以下步骤：步骤一：将多种不同的注塑材料依次添加进入聚丙烯管加工装置内；步骤二：第一种注塑材料在内筒机构上注塑形成支撑内层；步骤三：调层机构调整注层机构的层数,在支撑内层上依次形成多层包覆层；一种聚丙烯管,所述聚丙烯管由支撑内层和包覆在支撑内层上的多层包覆层构成,支撑内层和多层包覆层的注塑材料不同；一种聚丙烯管加工装置,包括装置支架、冷却机构、注层机构、内筒机构、注塑机构和调层机构,可以制备多层不同材料构成的聚丙烯管。(The invention relates to the field of polypropylene pipes, in particular to a polypropylene pipe and a processing technology thereof, wherein the processing technology of the polypropylene pipe comprises the following steps: the method comprises the following steps: adding a plurality of different injection molding materials into a polypropylene pipe processing device in sequence; step two: the first injection molding material is injected on the inner cylinder mechanism to form a support inner layer; step three: the layer adjusting mechanism adjusts the layer number of the layer injecting mechanism, and a plurality of coating layers are sequentially formed on the inner support layer; the polypropylene pipe is composed of a support inner layer and a plurality of coating layers coated on the support inner layer, wherein the injection molding materials of the support inner layer and the coating layers are different; a polypropylene pipe processing device comprises a device support, a cooling mechanism, a layer injection mechanism, an inner cylinder mechanism, an injection molding mechanism and a layer adjusting mechanism, and can be used for preparing a plurality of layers of polypropylene pipes made of different materials.)

1. A polypropylene pipe processing technology is characterized in that: the process comprises the following steps:

the method comprises the following steps: adding a plurality of different injection molding materials into a polypropylene pipe processing device in sequence;

step two: injection molding a first injection molding material on the inner barrel mechanism (40) to form a support inner layer (71);

step three: the layer adjusting mechanism (60) adjusts the layer number of the layer injecting mechanism (30) and sequentially forms a plurality of coating layers (73) on the supporting inner layer (71).

2. The polypropylene pipe processing technology according to claim 1, wherein: the polypropylene pipe processing device comprises a device support (10), a cooling mechanism (20) fixedly connected to the device support (10), a layer injection mechanism (30) connected to the cooling mechanism (20) in a sliding mode, and an inner cylinder mechanism (40) arranged coaxially with the layer injection mechanism (30).

3. The polypropylene pipe processing technology according to claim 2, wherein: the cooling mechanism (20) comprises a cooling cavity (21) and a cooling inner cylinder (23) which is rotatably connected inside the cooling cavity (21), and a cooling pipeline (22) is arranged on the cooling cavity (21).

4. The polypropylene pipe processing technology according to claim 3, wherein: fixedly connected with cooling keeps off ring (24) on cooling inner tube (23), is provided with a plurality of spacing archs I (25) on cooling keeps off ring (24), is provided with a plurality of relief holes I (26) on cooling keeps off ring (24).

5. The polypropylene pipe processing technology according to claim 2, wherein: the layer injection mechanism (30) is composed of a plurality of layer injection cylinders (31) which are mutually wrapped, the diameters of the layer injection cylinders (31) are different, and the layer injection cylinders (31) are mutually connected in a sliding manner.

6. The polypropylene pipe processing technology according to claim 5, wherein: the equal fixedly connected with in the front end of every notes a layer section of thick bamboo (31) annotates a layer and keeps off ring I (34), and the equal fixedly connected with in the rear end of every notes a layer section of thick bamboo (31) annotates a layer and keeps off ring II (36), all is provided with a plurality of relief holes II (38) on every notes a layer fender ring II (36), all is provided with a plurality of single direction mechanisms (33) on every notes a layer section of thick bamboo (31), and the equal fixedly connected with pull ring I (35) in the rear end of every notes a layer section of thick bamboo (31).

7. The polypropylene pipe processing technology according to claim 2, wherein: the inner cylinder mechanism (40) comprises an inner supporting column (41) and a plurality of inner supporting cylinders (43) which are connected to the inner supporting column (41) in a sliding mode, and the diameters of the plurality of inner supporting cylinders (43) are different.

8. The polypropylene pipe processing technology according to claim 2, wherein: the device is characterized by further comprising an injection molding mechanism (50) used for injection molding between the layer injection mechanism (30) and the inner cylinder mechanism (40), and the injection molding mechanism (50) is fixedly connected between the device support (10) and the cooling mechanism (20).

9. The polypropylene pipe processing technology according to claim 2, wherein: the device also comprises a layer adjusting mechanism (60) used for adjusting the injection layer number of the layer injection mechanism (30) and the inner cylinder mechanism (40), and the layer adjusting mechanism (60) is connected to the device support (10).

10. A polypropylene pipe processed by the polypropylene pipe processing technique of claim 1, wherein: the polypropylene pipe is composed of a support inner layer (71) and a plurality of coating layers (73) coated on the support inner layer (71), and the injection molding materials of the support inner layer (71) and the plurality of coating layers (73) are different.

Technical Field

The invention relates to the field of polypropylene pipes, in particular to a polypropylene pipe and a processing technology thereof.

Background

The polypropylene pipe is commonly called as PP pipe and is mainly used in the industries of chemical industry, petroleum, chlor-alkali, pharmacy, dye, pesticide, food, metallurgy, electroplating, environmental protection, water treatment and the like, the polymer type PP material has lower heat distortion temperature of 100 ℃, low transparency, low glossiness and low rigidity, and the impact strength of PP is increased along with the increase of ethylene content; the PP pipe is light in weight, has the specific gravity of only one eighth of that of a steel pipe, and is easy to mount, transport and connect; however, the polypropylene tube preparation process in the prior art cannot prepare a polypropylene tube composed of multiple layers of different materials.

Disclosure of Invention

The invention aims to provide a polypropylene pipe and a processing technology thereof, which can be used for preparing a polypropylene pipe consisting of a plurality of layers of different materials.

The purpose of the invention is realized by the following technical scheme:

a polypropylene pipe processing device comprises a device support, a cooling mechanism, a layer injection mechanism, an inner cylinder mechanism, an injection molding mechanism and a layer adjusting mechanism, wherein the cooling mechanism is connected to the device support, the layer injection mechanism is connected in the cooling mechanism in a sliding manner, the injection molding mechanism is fixedly connected between the device support and the cooling mechanism, the inner cylinder mechanism is connected in the injection molding mechanism in a rotating manner, the layer adjusting mechanism is connected to the device support, and the layer injection mechanism and the inner cylinder mechanism are both connected to the layer adjusting mechanism in a rotating manner;

the cooling mechanism comprises a cooling cavity, a cooling pipeline, a cooling inner barrel, a cooling baffle ring, a limiting protrusion I and a discharge hole I, the cooling pipeline is fixedly connected onto the cooling cavity, the cooling pipeline is communicated with the cooling cavity, the cooling inner barrel is rotatably connected into the cooling cavity, a power mechanism I for driving the cooling inner barrel to rotate is arranged on the cooling inner barrel, the power mechanism I is preferably a servo motor, the cooling baffle ring is fixedly connected onto the rear end of the cooling inner barrel, a plurality of discharge holes I are formed in the cooling baffle ring, and a plurality of limiting protrusions I are arranged on the cooling baffle ring to fixedly connect the cooling cavity onto the device support;

the injection layer mechanism is composed of a plurality of injection layer barrels which are mutually coated, the diameters of the injection layer barrels are different, a plurality of limiting grooves I are arranged on each injection layer barrel, a plurality of one-way mechanisms are arranged on each injection layer barrel, an injection layer baffle ring I is fixedly connected to the front end of each injection layer barrel, a pull ring I is fixedly connected to the rear end of each injection layer barrel, an injection layer baffle ring II is fixedly connected to the rear end of each injection layer barrel, a plurality of limiting bulges II are arranged on each injection layer baffle ring II, a plurality of discharge holes II are arranged on each injection layer baffle ring II, the injection layer barrel positioned on the outermost layer is slidably connected in the cooling inner barrel, the limiting bulges I are respectively slidably connected in the corresponding limiting grooves I, the injection layer baffle ring I positioned on the outermost layer is contacted with the inner wall of the cooling inner barrel, the limiting bulges II positioned on the outer side are respectively slidably connected in the limiting grooves I positioned on the inner side, the injection layer baffle ring I positioned on the inner side is contacted with the inner wall of the injection layer barrel positioned on the outer side;

the inner cylinder mechanism comprises an inner support column and a plurality of layers of inner support cylinders coated on the inner support column, a plurality of limiting grooves II are formed in the inner support column, a plurality of limiting grooves III are formed in the outer side of the inner support cylinder, a plurality of limiting bulges III are formed in the inner side of the inner support cylinder, a pull ring II is fixedly connected to each inner support cylinder, the limiting bulges III on the innermost inner support cylinder are respectively connected to the limiting grooves II in a sliding mode, the limiting bulges III on the outer side inner support cylinder are respectively connected to the limiting grooves III on the inner side inner support cylinder in a sliding mode, the inner support column is rotatably connected to the injection molding mechanism, a power mechanism II for driving the inner support column to rotate is arranged on the inner support column, and the power mechanism II is preferably a servo motor;

the injection molding mechanism comprises an injection molding cylinder I, an injection molding cylinder II and an injection molding cavity I, the injection molding device comprises an injection molding pipeline I, an injection molding baffle, an injection molding cavity II and an injection molding pipeline II, wherein the injection molding barrel I is fixedly connected to a device bracket, the injection molding barrel II is fixedly connected to a cooling cavity, the injection molding cavity I is rotatably connected between the injection molding barrel I and the injection molding barrel II, a power mechanism III for driving the injection molding cavity I to rotate is arranged on the injection molding cavity I, the power mechanism III is preferably a servo motor, a plurality of injection molding pipelines I are fixedly connected to the injection molding cavity I, each injection molding pipeline I is communicated with the injection molding cavity I, the injection molding baffle is fixedly connected to the injection molding pipeline I, the injection molding cavity II is rotatably connected to the injection molding baffle, the injection molding pipeline II is fixedly connected to the injection molding cavity II, the injection molding pipeline II is communicated with the injection molding cavity II, the injection molding cavity II is communicated with the injection molding pipeline I, and an inner support column is rotatably connected to the injection molding barrel I;

the layer adjusting mechanism comprises a plurality of layer adjusting lead screws and a plurality of layer adjusting pull rings, the layer adjusting lead screws are connected to the device support in a rotating mode, each layer adjusting lead screw is connected to a layer adjusting pull ring through threads, the layer adjusting pull rings are connected to the injection molding barrel I in a sliding mode, and the pull rings I and the pull rings II are connected to the layer adjusting pull rings in a rotating mode respectively.

A polypropylene pipe processing technology comprises the following steps:

the method comprises the following steps: adding a plurality of different injection molding materials into a polypropylene pipe processing device in sequence;

step two: the first injection molding material is injected on the inner cylinder mechanism to form a support inner layer;

step three: the layer adjusting mechanism adjusts the layer number of the layer injecting mechanism, and multiple coating layers are sequentially formed on the inner supporting layer.

The polypropylene pipe is composed of a support inner layer and a plurality of layers of coating layers coated on the support inner layer, wherein the injection molding materials of the support inner layer and the plurality of layers of coating layers are different.

Drawings

The invention is described in further detail below with reference to the accompanying drawings and specific embodiments.

FIG. 1 is a schematic view of the process for producing a polypropylene tube according to the present invention;

FIG. 2 is a schematic structural diagram of a polypropylene tube processing apparatus according to the present invention;

FIG. 3 is a schematic structural view of a cross-sectional view of a polypropylene tube processing apparatus according to the present invention;

FIG. 4 is a schematic view of the device mounting structure of the present invention;

FIG. 5 is a schematic view of the cooling mechanism of the present invention;

FIG. 6 is a schematic cross-sectional view of the cooling mechanism of the present invention;

FIG. 7 is a schematic structural diagram of the injection mechanism of the present invention;

FIG. 8 is a schematic structural view of a cross-sectional view of the injection mechanism of the present invention;

FIG. 9 is a schematic structural diagram of the injection mechanism of the present invention;

FIG. 10 is a schematic view of the inner barrel mechanism of the present invention;

FIG. 11 is a schematic structural view of the inner barrel mechanism of the present invention;

FIG. 12 is a schematic view of the inner barrel mechanism of the present invention;

FIG. 13 is a schematic view of the injection mechanism of the present invention;

FIG. 14 is a schematic cross-sectional view of the injection molding mechanism of the present invention;

FIG. 15 is a schematic structural view of a layer-adjusting mechanism of the present invention;

fig. 16 is a schematic view of a polypropylene tube structure of the present invention.

In the figure: a device holder 10; a cooling mechanism 20; a cooling chamber 21; a cooling duct 22; cooling the inner cylinder 23; the cooling baffle ring 24; a limiting bulge I25; a discharge hole I26; a layer injection mechanism 30; a layer injection cylinder 31; a limiting groove I32; a one-way mechanism 33; injecting a layer baffle ring I34; a pull ring I35; injecting a layer baffle ring II 36; a limiting bulge II 37; a discharge hole II 38; an inner cylinder mechanism 40; an inner support column 41; a limiting groove II 42; an inner support cylinder 43; a limit groove III 44; a limiting bulge III 45; a pull ring II 46; an injection molding mechanism 50; an injection molding barrel I51; an injection molding cylinder II 52; an injection molding cavity I53; injection molding a pipeline I54; an injection molded baffle 55; an injection molding cavity II 56; injection molding a pipeline II 57; a layer adjusting mechanism 60; a layer adjusting screw rod 61; a leveling tab 62; a support inner layer 71; the coupling projection 72; a coating 73.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings.

A polypropylene pipe processing technology comprises the following steps:

the method comprises the following steps: adding a plurality of different injection molding materials into a polypropylene pipe processing device in sequence;

step two: a first injection molding material is injection molded on the inner barrel mechanism 40 to form the support inner layer 71;

step three: the layer adjusting mechanism 60 adjusts the layer number of the layer injecting mechanism 30, and a plurality of coating layers 73 are sequentially formed on the supporting inner layer 71;

a polypropylene pipe is composed of a support inner layer 71 and a plurality of coating layers 73 coated on the support inner layer 71, wherein the injection molding materials of the support inner layer 71 and the plurality of coating layers 73 are different.

In order to solve the technical problem of how to prepare a polypropylene pipe made of multiple layers of different materials in the prior art, the mechanism and the working principle of a polypropylene pipe processing device are explained in detail below, the polypropylene pipe processing device comprises a device support 10, a cooling mechanism 20, a layer injection mechanism 30, an inner cylinder mechanism 40, an injection mechanism 50 and a layer adjustment mechanism 60, wherein the cooling mechanism 20 is connected to the device support 10, the layer injection mechanism 30 is connected in the cooling mechanism 20 in a sliding manner, the injection mechanism 50 is fixedly connected between the device support 10 and the cooling mechanism 20, the inner cylinder mechanism 40 is rotationally connected in the injection mechanism 50, the layer adjustment mechanism 60 is connected to the device support 10, and the layer injection mechanism 30 and the inner cylinder mechanism 40 are both rotationally connected to the layer adjustment mechanism 60;

when the injection molding mechanism is used, different raw materials are sequentially introduced into the injection molding mechanism 50, the injection molding mechanism 50 sequentially introduces different raw materials between the layer injection mechanism 30 and the inner cylinder mechanism 40, the cooling mechanism 20 cools and molds a first raw material between the layer injection mechanism 30 and the inner cylinder mechanism 40 to form a support inner layer 71, the layer adjusting mechanism 60 is started, the layer adjusting mechanism 60 drives the layer injection mechanism 30 to move, the layer number of the layer injection mechanism 30 is adjusted, namely the inner diameter formed by injection molding of the layer injection mechanism 30 is changed, a second raw material is injected between the layer injection mechanism 30 and the inner cylinder mechanism 40, a coating layer 73 is formed on the support inner layer 71, and then a plurality of coating layers 73 are formed by processing, so that polypropylene pipes made of different materials are formed;

in order to solve the problem of cooling and forming the raw material entering between the layer injection mechanism 30 and the inner cylinder mechanism 40, the cooling mechanism 20 is further arranged, the structure and raw materials of the cooling mechanism 20 are explained in detail below, the cooling mechanism 20 comprises a cooling cavity 21, a cooling pipeline 22, a cooling inner cylinder 23, a cooling baffle ring 24, a limiting protrusion I25 and a material discharge hole I26, the cooling pipeline 22 is fixedly connected to the cooling cavity 21, the cooling pipeline 22 is communicated with the cooling cavity 21, the cooling inner cylinder 23 is rotatably connected to the cooling cavity 21, a power mechanism I for driving the cooling inner cylinder 23 to rotate is arranged on the cooling inner cylinder 23, the power mechanism I is preferably a servo motor, the cooling baffle ring 24 is fixedly connected to the rear end of the cooling inner cylinder 23, the material discharge holes I26 are arranged on the cooling baffle ring 24, and the cooling cavity 21 provided with the limiting protrusions I25 is fixedly connected to the device support 10;

as shown in fig. 5 and 6, a cooling water pipeline is connected to the cooling pipeline 22 in advance, the cooling water is introduced between the cooling cavity 21 and the cooling inner cylinder 23, so as to cool the inner space of the cooling inner cylinder 23, when the cooling inner cylinder 23 needs to rotate, the power mechanism i is started, the power mechanism i can be fixedly connected to the device bracket 10, the output shaft of the power mechanism i is in transmission connection with the cooling inner cylinder 23, the output shaft of the power mechanism i drives the cooling inner cylinder 23 to rotate, the cooling inner cylinder 23 drives the injection layer mechanism 30 which is connected with the cooling inner cylinder in a sliding manner to rotate, when the injection layer mechanism 30 rotates, the injection molding raw material can be uniformly coated on the support inner layer 71, and the injection layer mechanism 30 and the coating layer 73 formed by injection molding can be prevented from being sticky, so that the coating layer 73 and the injection layer mechanism 30 are inconvenient to separate;

in order to solve the technical problem of how to change the internal diameter of the injection layer mechanism 30, the injection layer mechanism 30 is further provided, the structure and raw materials of the injection layer mechanism 30 are explained in detail below, the injection layer mechanism 30 is composed of a plurality of injection layer cylinders 31 which are mutually coated, the diameters of the plurality of injection layer cylinders 31 are different, each injection layer cylinder 31 is provided with a plurality of limiting grooves I32, each injection layer cylinder 31 is provided with a plurality of one-way mechanisms 33, the front end of each injection layer cylinder 31 is fixedly connected with an injection layer baffle ring I34, the rear end of each injection layer cylinder 31 is fixedly connected with a pull ring I35, the rear end of each injection layer cylinder 31 is fixedly connected with an injection layer baffle ring II 36, each injection layer baffle ring II 36 is provided with a plurality of limiting bulges II 37, each injection layer baffle ring II 36 is provided with a plurality of discharge holes II 38, the injection layer cylinder 31 positioned at the outermost layer is connected in the cooling inner cylinder 23 in a sliding manner, the limiting protrusions I25 are respectively connected in the corresponding limiting grooves I32 in a sliding mode, the injection layer baffle ring I34 located on the outermost layer is in contact with the inner wall of the cooling inner cylinder 23, the limiting protrusions II 37 located on the outer side are respectively connected in the limiting grooves I32 located on the inner side in a sliding mode, and the injection layer baffle ring I34 located on the inner side is in contact with the inner wall of the injection layer cylinder 31 located on the outer side;

as shown in fig. 7 to 9, a plurality of injection layer cylinders 31 with different diameters are connected with each other in a sliding manner through a limiting groove i 32 and a limiting protrusion ii 37, when the inner diameter of the injection layer mechanism 30 needs to be adjusted, the injection layer cylinder 31 located at the innermost side is pushed to slide, so that the injection layer cylinder 31 located at the innermost side slides out between the cooling mechanism 20 and the inner cylinder mechanism 40, and when the diameter inside the injection layer mechanism 30 needs to be adjusted again, the second injection layer cylinder 31 located at the inner side is pushed to slide, so that the second injection layer cylinder 31 located at the inner side slides out between the cooling inner cylinder 23 and the inner cylinder mechanism 40, and the inner diameter of the injection layer mechanism 30 during cooling molding is adjusted;

further, in order to ensure that the injection molding raw material can be introduced between the injection mechanism 30 and the inner cylinder mechanism 40 when the inner diameter of the injection mechanism 30 changes, a one-way mechanism 33 and a discharge hole II 38 are further provided, the one-way mechanism 33 can be a one-way valve commonly used in the prior art, the raw material can be limited to move only from the outside of the injection cylinder 31 to the inside of the injection cylinder 31, when the raw material is introduced between the injection mechanism 30 and the inner cylinder mechanism 40, a part of the raw material enters between the injection mechanism 30 and the inner cylinder mechanism 40 through the injection cylinder 31 positioned at the inner side, a part of the raw material enters between the two injection cylinders 31 through the discharge hole II 38, as shown in FIG. 8, enters between the injection mechanism 30 and the inner cylinder mechanism 40 through the one-way mechanism 33, each injection cylinder 31 is provided with a plurality of one-way mechanisms 33, and then enters between the injection mechanism 30 and the inner cylinder mechanism 40 in multiple directions, thereby ensuring the raw material amount between the layer injection mechanism 30 and the inner cylinder mechanism 40;

meanwhile, when the inner diameter of the layer injection mechanism 30 is adjusted, due to the existence of the layer injection baffle ring I34, when the layer injection barrel 31 moves, the layer injection baffle ring I34 moves along with the layer injection barrel 31, the layer injection baffle ring I34 extrudes raw materials between the two layer injection barrels 31, so that the raw materials between the two layer injection barrels 31 are discharged out of the space between the two layer injection barrels 31 through the discharge hole II 38, further, the situation that no raw materials remain between the two layer injection barrels 31 is ensured, and the situation that the raw materials block sliding of the layer injection barrels 31 after being cooled and formed is prevented;

after a first raw material is introduced between the injection layer mechanism 30 and the inner cylinder mechanism 40, starting the power mechanism I, starting the injection layer mechanism 30 to rotate by the power mechanism I, cooling the raw material between the injection layer mechanism 30 and the inner cylinder mechanism 40 by the cooling mechanism 20 to form a supporting inner layer 71, pushing the injection layer cylinder 31 to slide, adjusting the inner diameter of the injection layer mechanism 30, introducing a second raw material between the injection layer mechanism 30 and the inner cylinder mechanism 40, starting the injection layer mechanism 30 to rotate by the power mechanism I, cooling the raw material between the injection layer mechanism 30 and the inner cylinder mechanism 40 by the cooling mechanism 20, forming a coating layer 73 on the basis of the supporting inner layer 71 by the second raw material, introducing a third raw material between the injection layer mechanism 30 and the inner cylinder mechanism 40, and repeating the steps to prepare a multilayer coating layer 73;

further, in order to adjust the inner diameter of the polypropylene pipe formed by injection molding, an inner cylinder mechanism 40 is further provided, and the structure and raw materials of the inner cylinder mechanism 40 are explained in detail below, wherein the inner cylinder mechanism 40 comprises an inner support column 41 and a multilayer inner support cylinder 43 coated on the inner support column 41, a plurality of limiting grooves II 42 are provided on the inner support column 41, a plurality of limiting grooves III 44 are provided on the outer side of the inner support cylinder 43, a plurality of limiting protrusions III 45 are provided on the inner side of the inner support cylinder 43, each inner support cylinder 43 is fixedly connected with a pull ring II 46, the plurality of limiting protrusions III 45 on the innermost inner support cylinder 43 are respectively connected on the plurality of limiting grooves II 42 in a sliding manner, the plurality of limiting protrusions III 45 on the outer inner support cylinder 43 are respectively connected in the plurality of limiting grooves III 44 on the inner support cylinder 43 in a sliding manner, the inner support column 41 is rotatably connected in the injection molding mechanism 50, a power mechanism II for driving the inner support column 41 to rotate is arranged on the inner support column, and the power mechanism II is preferably a servo motor;

as shown in fig. 16, the connecting protrusion 72 provided on the polypropylene tube is formed by the limiting groove ii 42 on the inner cylinder mechanism 40, and mainly prevents the supporting inner layer 71 from rotating along with the injection layer mechanism 30 when the coating layer 73 is processed after the supporting inner layer 71 is formed by injection molding, so as to prevent the supporting inner layer 71 and the injection layer mechanism 30 from being incapable of rotating relatively, i.e. it is ensured that the injection layer mechanism 30 is injected uniformly, and it is also ensured that the coating layer 73 and the injection layer mechanism 30 are separated;

as shown in fig. 10 to 12, when the outer diameter of the inner cylinder mechanism 40 needs to be adjusted, only the inner support cylinder 43 needs to be pushed to slide on the inner support column 41, so as to adjust the diameter of the portion of the inner cylinder mechanism 40 in the cooling mechanism 20, and further prepare polypropylene pipes with different inner diameters according to different use requirements;

furthermore, the device is also provided with a power mechanism II, the power mechanism II can drive the support column 41 to rotate, the device can also be used for preparing polypropylene pipes made of a single material and having different inner and outer diameters according to different use requirements, when the polypropylene pipes made of the single material are required to be injected, the inner and outer diameters of the injection layer mechanism 30 and the inner cylinder mechanism 40 only need to be adjusted according to the use requirements, the power mechanism II can be started at the same time, the power mechanism II drives the inner cylinder mechanism 40 to rotate, the polypropylene pipes are prevented from being adhered to the inner cylinder mechanism 40 after being formed, the uniform injection molding is ensured, and meanwhile, the polypropylene pipes made of the single material are not required to be formed in the cooling mechanism 20, so the length of the polypropylene pipes made of the single material is not limited by the length of the cooling mechanism 20;

the structure and the function of the injection molding mechanism 50 are explained below, the injection molding mechanism 50 comprises an injection molding barrel I51, an injection molding barrel II 52, an injection molding cavity I53, an injection molding pipeline I54, an injection molding baffle 55, an injection molding cavity II 56 and an injection molding pipeline II 57, the injection molding barrel I51 is fixedly connected to the device support 10, the injection molding barrel II 52 is fixedly connected to the cooling cavity 21, the injection molding cavity I53 is rotatably connected between the injection molding barrel I51 and the injection molding barrel II 52, a power mechanism III for driving the injection molding cavity I53 to rotate is arranged on the injection molding cavity I53, the power mechanism III is preferably a servo motor, a plurality of injection molding pipelines I54 are fixedly connected to the injection molding cavity I53, each injection molding pipeline I54 is communicated with the injection molding cavity I53, the injection molding baffle 55 is fixedly connected to the injection molding baffle 55, the injection molding cavity II 56 is rotatably connected to the injection molding cavity II 56, and the injection molding pipeline II 57 is fixedly connected to the injection molding cavity II 56, the injection molding pipeline II 57 is communicated with the injection molding cavity II 56, the injection molding cavity II 56 is communicated with the injection molding pipeline I54, and the inner support column 41 is rotatably connected to the injection molding barrel I51;

as shown in fig. 13 to 14, when a multi-layer polypropylene tube needs to be prepared, different raw materials are sequentially introduced into an injection molding pipeline ii 57, when a single-material polypropylene tube needs to be prepared, a single raw material is introduced into the injection molding pipeline ii 57, the injection molding raw material enters an injection molding cavity ii 56 through the injection molding pipeline ii 57, a power mechanism iii is started, the power mechanism iii drives an injection molding cavity i 53 to rotate, the injection molding raw material is ensured to uniformly enter a space between an injection molding barrel i 51 and an injection molding barrel ii 52, and the injection molding quality is ensured;

in order to adjust the inner diameter and the outer diameter of the layer injection mechanism 30 and the inner cylinder mechanism 40 conveniently, a layer adjusting mechanism 60 is further arranged, the structure and the function of the layer adjusting mechanism 60 are explained below, the layer adjusting mechanism 60 comprises a layer adjusting screw rod 61 and a layer adjusting pull ring 62, the layer adjusting screw rods 61 are provided with a plurality of layers, the layer adjusting screw rods 61 are all rotatably connected to the device support 10, each layer adjusting screw rod 61 is connected with the layer adjusting pull ring 62 through threads, the layer adjusting pull rings 62 are all slidably connected to the injection molding cylinder I51, and the pull rings I35 and the pull rings II 46 are respectively rotatably connected to the layer adjusting pull rings 62; the layer-adjusting screw rod 61 is rotated, the corresponding layer-adjusting pull ring 62 is driven to move through threads when the layer-adjusting screw rod 61 rotates, the layer-adjusting pull ring 62 drives the corresponding pull ring I35 or pull ring II 46 to move, and then the inner diameter and the outer diameter of the layer-injecting mechanism 30 and the inner cylinder mechanism 40 are adjusted.