CN105715882B - A kind of small-diameter bamboo winding composite pipe and its manufacturing method - Google Patents

Abstract

The invention belongs to the related field of composite pipes, and discloses a small-caliber bamboo winding composite pipe. It is made of fiber felt or non-woven fabric with anti-corrosion resin; the middle reinforcement layer is formed by multi-layer helical winding of a single bamboo sheet with a certain size and specification adhered to the inner lining layer, and its total thickness accounts for More than 75% of the overall pipe wall thickness; the outer protective layer is coated and solidified on the outer surface of the middle reinforcement layer, and plays the role of waterproof, anti-corrosion and radiation protection. The invention also discloses a corresponding preparation method. Through the present invention, even in the case of a small-diameter specification of less than 200mm, the characteristics of no stress distribution defects in the overall structure of the bamboo winding composite pipe can be well maintained, and at the same time, the characteristics of compression resistance, ring stiffness, and fluid transportation energy consumption can be significantly improved. And the comprehensive performance in terms of long-term use quality stability.

Description

A kind of small-diameter bamboo winding composite pipe and its manufacturing method

technical field

The invention belongs to the related technical field of composite pipes, and more specifically relates to a small-diameter bamboo winding composite pipe and a manufacturing method thereof.

Background technique

At present, various types of pipes are widely used in many industries at home and abroad. Traditional pipes are mainly divided into metal pipes (such as seamless steel pipes, ductile cast iron pipes, etc.), plastic pipes (such as PVC pipes, HDPE pipes, etc.), cement pipes, and glass steel pipes (such as sand-filled glass steel pipes). Different performance characteristics, but also present different advantages and disadvantages: for example, seamless steel pipe has high pressure bearing capacity, high temperature resistance, easy processing, but heavy weight, easy corrosion, difficult construction and average service life; HDPE pipe is light in weight, durable Corrosion, easy to process, but poor temperature resistance and pressure bearing capacity, small rigidity and easy to age; sand-filled glass steel pipe has high strength, corrosion resistance, and small friction coefficient, but its pressure bearing capacity is limited in the case of large diameters, long-term Glass fiber may be precipitated when used, and it is not conducive to recycling, etc.

In view of this, the inventors of the present application have already proposed a new type of bio-based pipe material that uses bamboo fiber as the main reinforcement material, resin as the binder, and processed by winding. For example, CN200910099279.2 discloses a method for preparing a bamboo fiber wound composite pipe, wherein the pipe is arranged as an inner liner, a reinforcement layer and an outer protective layer from the inside to the outside, and the reinforcement layer is made of rolled bamboo fiber sheets Installed on the winding machine to unwind, first go through the resin tank to coat modified materials such as epoxy resin, then wind on the inner lining of the straight pipe mold and finally form it after curing. As another example, a bamboo composite pressure pipe is disclosed in CN201120458602.3, wherein the pipe is arranged as an inner liner, a reinforcement layer and an outer protective layer from the inside to the outside, and the main components of all layers are made of bamboo fiber and other materials. It is made by compounding, thereby obtaining a reinforced pipe product of all bamboo fibers. The basic principle of these new bio-based pipes is to make full use of the axial tensile strength of bamboo fibers and form a stress-free defect distribution in the pipe structure. Compared with conventional pipes, not only in compressive strength, stiffness, The weight, anti-corrosion and insulation performance are all excellent in many main indicators, and the raw materials are renewable resources. The production process basically does not emit three wastes, and has the characteristics of low-carbon environmental protection, energy saving and emission reduction.

However, with the promotion and practical application of bamboo winding composite pipes in many industries and projects, further research shows that for occasions such as pipeline transportation, small-diameter pipes are often used in large quantities to form pipe network branches, and In order to meet the stable performance during long-term transportation and use, there are also specific requirements in terms of its key performance indicators and processing and manufacturing processes. In other words, when some applications require the use of small-caliber bamboo winding composite pipes with specific specifications, how to make targeted designs based on the characteristics of the above-mentioned bio-based pipes so as to continue to maintain their unique performance characteristics, And in terms of ring stiffness, axial tensile strength, anti-leakage and low fluid transportation energy consumption, it meets the quality requirements of processing, manufacturing and long-term transportation and operation, which is becoming a technical problem that needs to be solved urgently in this field.

Contents of the invention

In view of the above deficiencies or improvement needs of the prior art, the present invention provides a small-diameter bamboo winding composite pipe and its manufacturing method, wherein the structural composition and arrangement of each key component are improved and redesigned, especially for Some important structural parameters that directly affect the small-diameter composite pipe in terms of processing, manufacturing and service reliability are adjusted and improved, so that the small-diameter bamboo-wound composite pipe can maintain its own stress-free defect distribution characteristics for a long time and stably , so it is especially suitable for applications such as oil and gas transportation, urban drainage and sewage, pipe network branch lines, etc.

In order to achieve the above object, according to one aspect of the present invention, a small-caliber bamboo winding composite pipe is provided, which is characterized in that the diameter of the inner hole of the bamboo winding composite pipe is less than 200mm, and the inner lining is sequentially included from the inside to the outside layer, middle reinforcement layer and outer protective layer; where:

The inner lining layer is made of fiber mat or non-woven fabric impregnated with adhesive, and forms an impermeable and smooth inner wall; the middle reinforcement layer is made of bamboo strips adhered with resin, which are evenly wound in multiple layers. The inner lining layer is solidified externally, and its total thickness accounts for more than 75% of the overall pipe wall thickness. In addition, the specifications of the bamboo strips are set to be 2mm-10mm wide, 0.6mm-1.2mm thick, and 2500mm long. , and the inner lining layer is wound in a spiral manner during the whole winding process; the outer protective layer is directly coated and cured on the outer surface of the middle reinforcement layer, and plays the role of waterproof, anti-corrosion and radiation protection effect.

For the technical solution formed by the above-mentioned idea of the present invention, the intermediate reinforcing layer is directly wound with a single bamboo strip and resin, which can not only significantly improve the processing efficiency and quality controllability, but more importantly, make the bamboo strip The helical winding process of the above angle range can be fully stretched, so that the axial tensile strength can be maximized; in addition, in view of the fact that the bamboo sheet is one of the core components of the middle reinforcement layer, its structural strength and even the entire small-diameter bamboo winding tube The ring stiffness of the pipe plays an important role. In the present invention, through the targeted design of its specific size and thickness ratio, the overall structure of the pipe can be well maintained without stress distribution defects when the inner diameter of the pipe is less than 200mm. The characteristics of the bamboo winding composite pipe can achieve a better balance between the required winding thickness and structural strength, and at the same time ensure the quality stability of the bamboo winding composite pipe in long-term use.

As an improved solution of the present invention, the number of winding layers of bamboo strips in the middle reinforcing layer is preferably 2-6 layers, and the winding angle gradually increases from inside to outside. Furthermore, the minimum wrapping angle is preferably set at 20°, and the angles of each layer are gradually increased from inside to outside at an angle of 3°-5° until the maximum wrapping angle of 80° is reached. Through the above design, the advantages of high axial strength and toughness of the bamboo fiber itself can be gradually and evenly spread to multiple directions of the pipe wall through the sequential increase of the winding angle from the inside to the outside, and play a role in stress interaction at multiple angles. The supplementary effect can significantly improve the phenomenon of bending or cracking of the pipe wall, and then ensure the pipe stiffness and internal pressure resistance of the small-diameter bamboo winding pipe under long-term use conditions.

As another improvement of the present invention, the cross-sectional shape of the above-mentioned bamboo strips is preferably processed into a rectangle, with a moisture content of 8% to 15%, and the overlap between adjacent bamboo strips is no more than 2mm in the length direction. . Through the above design, the rectangular bamboo strips not only help to overlap on the end faces, but also get closer to each other on the inner and outer sides, so that the middle reinforcement layer can fully obtain the bamboo fiber in all directions. High axial tensile strength characteristics; in addition, the bamboo strips and moisture content and lap overlap will also have a greater impact on the filling process of the resin component, the above specific specifications can make it easier for the resin to penetrate into each layer of bamboo strips It is fully combined with it, which in turn helps to improve the structural strength and impact resistance of the middle reinforcement layer.

As another improvement solution of the present invention, the total thickness of the above-mentioned intermediate reinforcing layer is set to account for 85%-90% of the wall thickness of the overall pipe. In this way, the core role played by the intermediate reinforcement layer on the pressure bearing of the entire small-diameter bamboo winding pipe can be fully utilized, and it is convenient to play a guiding role in the processing quality control between the various constituent layers.

As another improvement of the present invention, in addition to the bamboo strips and resin, bio-based fillers and curing agents can also be added to the above-mentioned intermediate reinforcement layer, wherein the resin, bio-based fillers and curing agents are between the three The parts by mass are set at 100:10-15:2-5, mixed together, poured and adhered to the bamboo strips. Further, the resin is selected from one of polyurethane resin, phenolic resin, urea-formaldehyde resin or epoxy resin; the bio-based filler is selected from bamboo, wood, hemp, straw, plant husk or other hard biological material, and its average mesh number is set at 20-80. Through the above design, the resin mixture containing bio-based fillers and curing agents can promote the filling and bonding between the adjacent bamboo sheets of each layer, and the above-mentioned specific types and particle sizes of bio-based fillers have a good relationship with bamboo fibers. Good affinity can further improve the structural strength of the middle reinforcement layer.

As another improvement of the present invention, for the above-mentioned inner lining layer, its thickness is 0.5 mm to 1.5 mm, and preferably includes a first inner lining layer and a second inner lining layer from the inside to the outside, wherein the first inner lining layer The thickness of the lining layer is smaller than that of the second lining layer, and the resin adhesion amount of the first lining layer is set to be larger than that of the second lining layer. In addition, the fiber felt or non-woven fabric in the above-mentioned inner lining layer is preferably bamboo fiber felt or bamboo fiber non-woven fabric; furthermore, the first inner lining layer preferably adopts 80g/m ² ~ 120g/m ² , And the bamboo fiber mat or bamboo fiber non-woven fabric with the dipping rate of the adhesive greater than 90%, the second inner lining layer is preferably 180g/m ² ~ 250g/m ² , and the dipping rate of the adhesive is greater than 75% bamboo fiber felt or bamboo fiber non-woven fabric. Through the above targeted design involving the composition structure and important parameters of the inner lining layer, the inner lining layer can maintain good internal pressure resistance and anti-seepage performance under the specification conditions of small pipe diameters, and promote the connection between the inner lining layer and the middle reinforcement layer. At the same time, it also helps to reduce friction and effectively reduce the energy consumption of fluid transportation.

As another improvement of the present invention, the thickness of the bamboo strips for removing yellow bamboo is set at 0.2 mm to 0.4 mm, and the thickness for removing green bamboo is set at 0.1 mm to 0.3 mm. Through the above design, the damage to the bamboo fiber vascular bundle can be avoided to the greatest extent, and the processed bamboo strips can be more intimately combined with the resin infiltration during winding, which is conducive to the stability and uniform filling of the resin, and Simultaneous curing can be better achieved in the subsequent curing process, thereby further improving the structural strength of the middle reinforcement layer.

According to another aspect of the present invention, a method for manufacturing a small-diameter bamboo winding composite pipe is also provided correspondingly, wherein the method comprises the following steps:

(a) Cutting of bamboo strips: cut the original bamboo into multiple sections along its length, and remove the bamboo green on the outer surface and the bamboo yellow on the inner surface of each section, and the thickness of the bamboo yellow removal is set to 0.2 mm ~ 0.4mm, the thickness of the bamboo green removal is set to 0.1mm ~ 0.3mm, and correspondingly a plurality of bamboo strips with a rectangular cross section, a width of 2mm ~ 10mm, a thickness of 0.6mm ~ 1.2mm, and a length of more than 2500mm are obtained. ;

(b) Preparation of inner lining layer: use fiber felt or non-woven fabric adhered with anti-corrosion resin on the straight pipe mold to make an inner lining layer with a thickness of 0.5 mm to 1.5 mm, and form an anti-seepage and smooth inner wall;

(c) Preparation of the middle reinforcement layer: unwind the prepared bamboo strips on a winding machine, pass through the resin tank and coat them with resin, and then wind them evenly in multiple layers in a spiral manner from the beginning to the end with respect to the inner lining layer On top of it, until the intermediate reinforcement layer of the required thickness is completed; during this process, the winding angle of the bamboo strips gradually increases from the inside to the outside, and is controlled so that the thickness of the final solidified intermediate reinforcement layer accounts for 75% of the overall pipe wall thickness above;

(d) Preparation of the outer protective layer: directly spray anti-corrosion, waterproof and radiation-proof materials on the outer surface of the middle reinforcing layer, and finally form the bamboo winding composite pipe product with the required small-caliber specification.

As further preferably, for the above-mentioned step (c), the minimum winding angle of the bamboo strips is 20°, and the angle of each layer is 3°-5°, which is successively increased from inside to outside until it reaches 80°. Maximum wrap angle.

Generally speaking, compared with the prior art, the above technical solution conceived by the present invention mainly has the following technical advantages:

1. The present invention first researches and improves the middle reinforcing layer as the main component of the pipe in terms of its specific structural composition and combination of key parameters, etc., wherein a single piece of bamboo strips is directly wound in a spiral manner from beginning to end, which can not only significantly Improve the processing efficiency and quality controllability, and also make the bamboo strips fully stretched during the winding process, so that the axial tensile strength can be maximized; in addition, through the improvement of the specific size specifications of the bamboo strips, combined with The design of the change of winding angle from inside to outside can play the function of stress complementation in multiple directions of the small-diameter pipe wall, so that the small-diameter bamboo winding pipe can also be ensured without the need for winding too many layers. Structural strength and performance stability under long-term use environment;

2. In the present invention, the lining layer is designed as a multi-layer structure, and at the same time, the performance specifications and component materials of each layer are designed in a targeted manner. In this way, the smoothness and corrosion resistance of the lining layer can be improved. In this way, even when the small-diameter bamboo winding pipe is used to transport solid-liquid coexisting mixed substances or media such as mortar, it is not easy to cause excessive energy consumption or The phenomenon of damaged lining layer and contribute to the mutual bonding strength with the middle reinforcement layer;

3. The processing technology of the small-diameter bamboo winding composite pipe of the present invention is basically carried out at normal temperature and pressure, which is convenient for quality control and has no three wastes in the production process. It has the characteristics of low-carbon environmental protection, energy saving and emission reduction, and the prepared bamboo winding The composite pipe can still maintain its own stress-free defect distribution characteristics for a long time and stably under the inner hole diameter specification below 200mm, so it can replace all kinds of conventional pipes and is especially suitable for oil and gas transportation, urban drainage and sewage, pipe network branch lines and other applications.

Description of drawings

Fig. 1 is the sectional view of the basic structure of the designed small diameter bamboo winding composite pipe according to the preferred embodiment of the present invention;

Fig. 2 is a flow chart of the process for small-diameter bamboo winding composite pipes according to the present invention;

Throughout the drawings, the same reference numerals are used to designate the same elements or structures, wherein:

1-Inner lining layer 2-Middle reinforcement layer 3-Outer protective layer

Detailed ways

In order to make the object, technical solution and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention, not to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not constitute a conflict with each other.

Fig. 1 is a cross-sectional view of the basic structure of a small-diameter bamboo winding composite pipe designed according to a preferred embodiment of the present invention. As shown in Figure 1, the inner hole diameter of the bamboo winding composite pipe is less than 200 mm, more preferably 80 mm to 160 mm, and mainly includes inner lining layer 1, middle reinforcing layer 2 and outer protective layer 3 from the inside to the outside. , which will be described in detail below.

The inner lining layer 1 is made of fiber felt or non-woven fabric adhered with anti-corrosion resin, and forms an impermeable and smooth inner wall. Its main function is to be in contact with various media to be transported, and to prevent corrosion Under the premise of providing the necessary internal pressure resistance, it is ensured that the layer can transport the medium with as low friction and energy consumption as possible.

In the present invention, in view of the use requirements of the small-diameter bamboo winding composite pipe, it is preferable to design the inner lining layer as a structure of 2 or more layers. Specifically, the inner lining layer includes a first inner lining from the inside to the outside. lining layer and the second lining layer, and the thickness of the first lining layer is designed to be smaller than the thickness of the second lining layer, and the resin adhesion amount of the first lining layer is designed to be greater than that of the second lining layer Amount of resin adhesion. In this way, the first inner lining layer on the inner side can be processed to form a smoother inner surface, reducing friction and energy consumption when conveying media, while the second inner lining layer on the opposite outer side can improve the overall inner lining layer. The anti-stress strength and the combination with the middle reinforcement layer 2 play a more important role, especially to avoid corrosion or impact damage to the inner lining layer and the entire pipe by the medium in the case of small-caliber transportation. In addition, bamboo fibers can also be used in the inner lining layer to form fiber mats or non-woven fabrics; more specifically, the first inner lining layer is preferably made of 80g/m ² -120g/m ² and adhesive Bamboo fiber felt or bamboo fiber non-woven fabric with a dipping rate of more than 90%, the second inner lining layer is preferably bamboo fiber with an adhesive dipping rate of more than 75% and 180g/m ² to 250g/m ² Felt or bamboo fiber non-woven fabric. As for the thickness of the entire inner liner, it is preferably 0.5 mm to 1.5 mm.

As another key component of the present invention, the intermediate reinforcement layer 2 plays a central role in the pipe stiffness and internal pressure resistance of the entire small-diameter bamboo winding composite pipe. Correspondingly, in the context of research and development in which the caliber of the entire pipe is significantly smaller than the specifications of ordinary pipes, it is necessary to focus on research and improvement of the middle reinforcement layer 2 in terms of its specific structural composition and key parameter combinations.

Specifically, in the present invention, the intermediate reinforcing layer 2 is formed by multilayers of bamboo strips adhered with resin and uniformly wound outside the inner lining layer and solidified, and its total thickness accounts for more than 75% of the overall pipe wall thickness , further preferably accounting for 85% to 90% of the overall pipe wall thickness; in addition, the specifications and dimensions of the bamboo strips are set to be 2mm to 10mm in width and 0.6mm to 1.2mm in thickness, and there is no special limitation on the length, and throughout the During the winding process, the inner lining layer is wound in a helical manner. According to a preferred embodiment of the present invention, the number of winding layers of bamboo strips in the middle reinforcement layer is preferably 2-6 layers, and the winding angle gradually increases from inside to outside. Furthermore, the minimum wrapping angle is preferably set at 20°, and the angles of each layer are gradually increased from inside to outside at an angle of 3°-5° until the maximum wrapping angle of 80° is reached.

Through the above targeted design, the intermediate reinforcement layer is directly wrapped with a single bamboo strip and resin, which can not only significantly improve the processing efficiency and quality controllability, but more importantly, the above-mentioned bamboo strips of specific sizes can be used in The whole helical winding process is fully stretched to maximize the axial tensile strength; in addition, because the helical winding is adopted from the beginning to the end and the winding angle can be gradually increased from the inside to the outside, the axis of the bamboo fiber itself can be correspondingly The advantages of high strength and toughness gradually spread to multiple directions of the pipe wall, and the stresses complement each other at multiple angles, which can significantly improve the phenomenon of bending or cracking of the pipe wall, and then ensure the small diameter The bamboo winding pipe can also maintain the characteristics of the overall structure of the pipe without stress distribution defects under long-term use conditions, and at the same time improve the performance of the bamboo winding composite pipe in terms of compression resistance and ring stiffness, especially those that can ensure long-term stable performance Stable and reliable.

According to another preferred embodiment of the present invention, in addition to the basic components of resin and bamboo strips, bio-based fillers and curing agents may also be added to the above-mentioned intermediate reinforcement layer. After actual testing, the resin, bio-based The mass parts between the filler and the curing agent are set at 100:15-25:2-5, and they are mixed together and then poured and adhered to the bamboo strip curtain. More specifically, the resin is selected from one of polyurethane resin, phenolic resin, urea-formaldehyde resin or epoxy resin; the bio-based filler is selected from bamboo, wood, hemp, straw, plant husk or other hard biological material, and its average mesh number is set at 20-80. Through the above design, the resin mixture containing bio-based fillers and curing agents can promote the filling and bonding between the adjacent bamboo sheets of each layer, and the above-mentioned specific types and particle sizes of bio-based fillers have a good relationship with bamboo fibers. Good affinity can further improve the overall structural strength and internal pressure resistance of the intermediate reinforcement layer, and help to speed up the molding efficiency and quality controllability during the winding process of the intermediate reinforcement layer.

According to another preferred embodiment of the present invention, an additional interface layer can be provided between the inner lining layer and the intermediate reinforcement layer. The interface layer can be made of an appropriate polymer modified resin and used to further improve the inner lining. The bonding strength between the layer and the middle reinforcement layer.

Finally, the outer protective layer 3 can be directly coated and cured on the outer surface of the middle reinforcement layer 2, and mainly plays the role of waterproof, anticorrosion and radiation protection. Specifically, the outer protective layer can also be sprayed as two or more layers, for example, materials such as epoxy resin, unsaturated polyester resin or asphalt can be used, and anti-radiation fillers are added, and its thickness is preferably at least 3mm, so that It can better protect small-diameter bamboo winding composite pipes in various harsh environments.

The manufacturing process of the bamboo winding composite pipe according to the present invention and the design of key process parameters will be explained more clearly in conjunction with some specific examples below.

Example 1

Cut the original bamboo into multiple sections along its length direction, and remove the bamboo green on the outer surface and the bamboo yellow on the inner surface of each section respectively, wherein the thickness of bamboo yellow removal is set to 0.2mm, and the thickness of bamboo green removal is set to 0.3mm, correspondingly make a plurality of bamboo strips with rectangular cross-section, width 4mm, thickness 1mm, length such as more than 2500mm, and then degrease, wash and dehydrate it for later use.

Wrap a layer of release film on the polished FRP straight pipe mold with an outer diameter of 200mm, and then use bamboo fiber non-woven fabric adhered with anti-corrosion resin to make a thickness of 0.5mm and a density of 80g/m on the pipe mold in sequence ² and the first lining layer with a dipping rate of 92% and the second lining layer with a thickness of 1mm, a density of 200g/ ^m2 and a dipping rate of 78%, wherein the resin can be epoxy resin, thus forming Waterproof and smooth inner wall.

After the inner liner is cured, the above-mentioned bamboo strips are unwound on the winding machine, and several strips pass through the resin tank and coated with resin, and then are evenly wound on the inner liner in 5 layers in a spiral manner from the beginning to the end, and the winding angle is set Set at 65 degrees, the overlapping overlap of adjacent bamboo strips is 2mm in the length direction, until the intermediate reinforcement layer whose thickness accounts for about 85% of the overall tube wall thickness after curing is completed.

After all the winding operations are completed, the middle reinforcing layer is solidified to form a tube blank, and then the demoulding process is performed to obtain a bamboo winding composite tube. Finally, spray a layer of unsaturated polyester resin with waterproof and anti-corrosion function on the outside of the pipe, with a thickness of about 1.5mm, and finally process and manufacture a bamboo winding composite pipe product with a diameter of 200mm.

Example 2

Cut the original bamboo into multiple sections along its length direction, and remove the bamboo green on the outer surface and the bamboo yellow on the inner surface of each section respectively, wherein the thickness of bamboo yellow removal is set to 0.4mm, and the thickness of bamboo green removal is set to 0.25mm, the cross-section is rectangular and the width is 6mm, the thickness is 0.6mm, and the length is more than 2500mm, such as a plurality of bamboo strips, which are then degreased, cleaned and dehydrated for later use.

Wrap a layer of release film on the polished FRP straight pipe mold with an outer diameter of 160mm, and then use bamboo fiber non-woven fabric adhered with anti-corrosion resin to make a thickness of 0.2mm and a density of 100g/m on the pipe mold in sequence ² The first inner lining layer with a dipping rate of 95% and the second inner lining layer with a thickness of 0.3mm, a density of 250g/ ^m2 and a dipping rate of 78%, wherein the resin can be selected from phenolic resin, thus forming Waterproof and smooth inner wall.

After the inner liner is cured, install the above-mentioned bamboo strips on the winding machine and unwind them. Multiple strips pass through the resin tank and are coated with resin. Then, they are evenly wound on the inner liner in 5 layers in a spiral manner from the beginning to the end. The initial winding angle Set to 20 degrees, and the winding angle increases sequentially from the inside to the outside according to the angle of 5 degrees for each layer. The overlapping overlap of the adjacent bamboo strips is 1.5mm in the length direction, until the thickness of the whole tube is accounted for after curing. The middle reinforcement layer is about 90% of the wall thickness.

After all the winding operations are completed, the middle reinforcing layer is solidified to form a tube blank, and then the demoulding process is performed to obtain a bamboo winding composite tube. Finally, spray a layer of unsaturated polyester resin with waterproof and anti-corrosion function on the outside of the pipe, with a thickness of about 1.5mm, and finally process and manufacture a bamboo winding composite pipe product with a diameter of 160mm.

Example 3

Cut the original bamboo into multiple sections along its length direction, and remove the bamboo green on the outer surface and the bamboo yellow on the inner surface of each section respectively, wherein the thickness of bamboo yellow removal is set to 0.4mm, and the thickness of bamboo green removal is set to 0.1 mm, correspondingly make a plurality of bamboo strips with a rectangular cross section, a width of 4 mm, a thickness of 1 mm, and a length of, for example, more than 2500 mm, which are then degreased, cleaned and dehydrated for later use.

Wrap a layer of release film on the polished FRP straight tube mold with an outer diameter of 160mm, and then use bamboo fiber non-woven fabric adhered with anti-corrosion resin to make a thickness of 0.5mm and a density of 100g/m on the tube mold in sequence ² The first inner lining layer with a dipping rate of 95% and the second inner lining layer with a thickness of 1mm, a density of 250g/ ^m2 and a dipping rate of 78%, wherein the resin can be selected from phenolic resin, thus forming a waterproof Permeable and smooth inner wall.

After the inner liner is cured, install the above-mentioned bamboo strips on the winding machine and unwind them. Multiple strips pass through the resin tank and are coated with resin. Then, they are evenly wound on the inner liner in 5 layers in a spiral manner from the beginning to the end. The initial winding angle Set to 30 degrees, and the winding angle increases sequentially from the inside to the outside according to the angle of 3 degrees for each layer. The overlapping overlap of adjacent bamboo strips is 1.2mm in the length direction, until the thickness of the whole tube is accounted for after curing. The middle reinforcement layer is about 87% of the wall thickness. In this process, the resin is selected as urea-formaldehyde resin and straw powder with an average mesh size of 20 and a small amount of curing agent are added, wherein the weight ratio of the resin, straw powder and curing agent is 100:15:5.

After all the winding operations are completed, the middle reinforcing layer is solidified to form a tube blank, and then the demoulding process is performed to obtain a bamboo winding composite tube. Finally, spray a layer of unsaturated polyester resin with waterproof and anti-corrosion function on the outside of the pipe, with a thickness of about 1.5mm, and finally process and manufacture a bamboo winding composite pipe product with a diameter of 160mm.

Example 4

Cut the original bamboo into multiple sections along its length direction, and remove the bamboo green on the outer surface and the bamboo yellow on the inner surface of each section respectively, wherein the thickness of the bamboo yellow removal is set to 0.35mm, and the bamboo green removal thickness is set to 0.2mm, the cross-section is rectangular and the width is 10mm, the thickness is 1mm, and a plurality of bamboo strips with a length of more than 2500mm are correspondingly prepared, and then it is treated by degreasing, cleaning and dehydration for subsequent use.

Wrap a layer of release film on the polished FRP straight tube mold with an outer diameter of 180mm, and then use bamboo fiber non-woven fabric adhered with anti-corrosion resin to make a thickness of 0.35mm and a density of 80g/m on the tube mold in sequence ² and the first inner lining layer with a dipping rate of 92% and the second inner lining layer with a thickness of 0.65mm and a density of 180g/ ^m2 and a dipping rate of 80%, wherein the resin can be selected from epoxy resin, thus Forms an impermeable and smooth inner wall.

After the inner liner is cured, install the above-mentioned bamboo strips on the winding machine and unwind them. Multiple strips pass through the resin tank and are coated with resin. Then, they are evenly wound on the inner liner in four layers in a spiral manner from the beginning to the end. The initial winding angle Set to 35 degrees, and the winding angle increases sequentially from the inside to the outside according to the angle of 5 degrees for each layer. The overlapping overlap of adjacent bamboo strips is 1mm in the length direction, until the thickness of the whole tube wall is accounted for after curing. The middle reinforcement layer is about 90% thick. In this process, the resin is selected as epoxy resin and added with an average mesh number of 80 bamboo powder and a small amount of curing agent, wherein the parts by weight between the resin, bamboo powder and curing agent are 100:15:3.

After all the winding operations are completed, the middle reinforcing layer is solidified to form a tube blank, and then the demoulding process is performed to obtain a bamboo winding composite tube. Finally, spray a layer of unsaturated polyester resin with waterproof and anti-corrosion function on the outside of the pipe, with a thickness of about 1.5mm, and finally process it into a bamboo winding composite pipe product with a diameter of 180mm.

Example 5

Cut the original bamboo into multiple sections along its length direction, and remove the bamboo green on the outer surface and the bamboo yellow on the inner surface of each section respectively, wherein the thickness of bamboo yellow removal is set to 0.2mm, and the thickness of bamboo green removal is set to 0.2mm, correspondingly make a plurality of bamboo strips whose cross-section is rectangular, 2mm wide, 1mm thick, and more than 2500mm long, and then degrease, clean and dehydrate it for later use.

Wrap a layer of release film on the polished FRP straight pipe mold with an outer diameter of 80mm, and then use bamboo fiber non-woven fabric adhered with anti-corrosion resin to make a thickness of 0.5mm and a density of 80g/m on the pipe mold in sequence ² The first inner lining layer with a dipping rate of 92% and the second inner lining layer with a thickness of 1mm, a density of 180g/ ^m2 and a dipping rate of 80%, wherein the resin can be epoxy resin, thus forming Waterproof and smooth inner wall.

After the inner liner is cured, install the above-mentioned bamboo strips on the winding machine and unwind them. Multiple strips pass through the resin tank and are coated with resin. Then, they are evenly wound on the inner liner in three layers in a spiral manner from the beginning to the end. The initial winding angle Set to 45 degrees, and the winding angle increases from the inside to the outside according to the angle of 3 degrees for each layer. The overlapping overlap of the adjacent bamboo strips is 1.5mm in the length direction, until the thickness of the whole tube is accounted for after curing. The middle reinforcement layer is about 86% of the wall thickness. In this process, the resin is selected as epoxy resin and added with straw powder with an average mesh number of 60 and a small amount of curing agent, wherein the weight parts between the resin, straw powder and curing agent are 100:12:5 .

After all the winding operations are completed, the middle reinforcing layer is solidified to form a tube blank, and then the demoulding process is performed to obtain a bamboo winding composite tube. Finally, spray a layer of unsaturated polyester resin with waterproof and anti-corrosion function on the outside of the pipe, with a thickness of about 1mm, and finally process and manufacture a bamboo winding composite pipe product with a diameter of 80mm.

Example 6

Cut the original bamboo into multiple sections along its length direction, and remove the bamboo green on the outer surface and the bamboo yellow on the inner surface of each section respectively, wherein the thickness of bamboo yellow removal is set to 0.4mm, and the thickness of bamboo green removal is set to 0.2 mm, the cross-section is rectangular and the width is 4 mm, the thickness is 1.2 mm, and a plurality of bamboo strips with a length of more than 2500 mm are correspondingly prepared, and then it is subjected to degreasing, cleaning and dehydration treatment for subsequent use.

Wrap a layer of release film on the polished FRP straight pipe mold with an outer diameter of 180mm, and then use bamboo fiber non-woven fabric adhered with anti-corrosion resin to make a thickness of 0.6mm and a density of 80g/m on the pipe mold in sequence ² and the first inner lining layer with a dipping rate of 92% and the second inner lining layer with a thickness of 0.8mm, a density of 180g/ ^m2 and a dipping rate of 80%, wherein the resin can be epoxy resin, thus Forms an impermeable and smooth inner wall.

After the inner liner is cured, install the above-mentioned bamboo strips on the winding machine and unwind them. Multiple strips pass through the resin tank and are coated with resin. Then, they are evenly wound on the inner liner in four layers in a spiral manner from the beginning to the end. The initial winding angle Set to 30 degrees, and the winding angle increases sequentially from the inside to the outside according to the angle of 4° for each layer. The overlapping overlap of the adjacent bamboo strips is 1.8mm in the length direction, until the thickness of the whole tube is accounted for after curing. The intermediate reinforcement layer is about 75% of the wall thickness. In this process, the weight ratio between the coconut shell powder powder and the curing agent for the resin is 100:15:2.

After all the winding operations are completed, the middle reinforcing layer is solidified to form a tube blank, and then the demoulding process is performed to obtain a bamboo winding composite tube. Finally, spray a layer of unsaturated polyester resin with waterproof and anti-corrosion function on the outside of the pipe, with a thickness of about 1.5mm, and finally process it into a bamboo winding composite pipe product with a diameter of 180mm.

It is easy for those skilled in the art to understand that the above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention, All should be included within the protection scope of the present invention.

Claims (40)

1. a kind of bamboo winding composite pipe of small diameter, it is characterized in that, the inner hole diameter of this bamboo winding composite pipe is below 200mm, and comprises liner, middle reinforcing layer and outer protective layer successively from inside to outside, wherein: The inner lining layer is made by curing fiber felt impregnated with adhesive, and forms an anti-seepage and smooth inner wall; The middle reinforcement layer is made of single bamboo strips adhered with resin, which are evenly wound and solidified outside the inner lining layer, and its total thickness accounts for more than 75% of the overall pipe wall thickness, wherein the bamboo strips The specifications and dimensions are set to be 2 mm to 10 mm wide and 0.6 mm to 1.2 mm thick, and are wound in a spiral manner relative to the inner lining layer during the entire winding process. The number of winding layers of bamboo strips in the middle reinforcement layer is 2 to 6 layers, and the winding angle gradually increases from the inside to the outside; in this way, the bamboo strips can be fully stretched during the entire spiral winding process, and at the same time, its axial strength and toughness characteristics of bamboo fibers It can gradually and evenly spread to multiple directions of the pipe wall, and play a complementary role in stress at multiple angles; The outer protective layer is directly coated and cured on the outer surface of the middle reinforcement layer, and plays the role of waterproof, anticorrosion and radiation protection. 2. The small-diameter bamboo winding composite pipe as claimed in claim 1, characterized in that the total thickness of the intermediate reinforcement layer is set to account for 85% to 90% of the overall pipe wall thickness. 3. The small-diameter bamboo winding composite pipe as claimed in claim 1, wherein the cross-sectional shape of the bamboo strips is processed into a rectangle, the moisture content is 8% to 15%, and the gap between adjacent bamboo strips is The degree of overlapping overlap in the length direction does not exceed 2mm. 4. The small-diameter bamboo winding composite pipe according to any one of claims 1-3, characterized in that, for the above-mentioned inner lining layer, its thickness is 0.5 mm to 1.5 mm, and it includes a second inner layer from the inside to the outside. an inner liner and a second inner liner, wherein the thickness of the first inner liner is smaller than that of the second inner liner, and the resin adhesion amount of the first inner liner is set to be greater than that of the second inner liner Floor. 5. The small-caliber bamboo winding composite pipe according to claim 4, characterized in that, the first inner lining layer is 80g/m ² -120g/m ² , and the dipping rate of the adhesive is greater than 90%. Bamboo fiber felt, the second inner lining layer is made of bamboo fiber felt with a weight of 180g/m ² -250g/m ² and an adhesive impregnation rate greater than 75%. 6. The small-diameter bamboo winding composite pipe as claimed in claim 5, characterized in that, the bamboo yellow removal thickness of the above-mentioned bamboo strips is set to 0.2mm to 0.4mm, and the bamboo green removal thickness is set to 0.1mm to 0.4mm. 0.3mm. 7. A method for manufacturing small-diameter bamboo winding composite pipes, characterized in that the method may further comprise the steps: (a) Cutting of bamboo strips: cut the original bamboo into multiple sections along its length, and remove the bamboo green on the outer surface and the bamboo yellow on the inner surface of each section, and the thickness of the bamboo yellow removal is set to 0.2 mm～0.4mm, the thickness of the bamboo green removal is set to 0.1mm～0.3mm, and correspondingly a plurality of bamboo strips with a rectangular cross section, a width of 2mm～10mm, and a thickness of 0.6mm～1.2mm are produced; (b) Preparation of the inner lining layer: on the straight pipe mold, a fiber felt adhered with anti-corrosion resin is used to make an inner lining layer with a thickness of 0.5 mm to 1.5 mm, and an anti-seepage and smooth inner wall is formed; (c) Preparation of the middle reinforcing layer: the prepared bamboo strips are unwound on a winding machine, and a plurality of strips pass through the resin tank and coated with resin, and then each single bamboo strip is spirally wound with respect to the inner lining layer from beginning to end. The method is to wind multiple layers evenly on it until the intermediate reinforcement layer of the required thickness is completed; in this process, the number of winding layers of the bamboo strips is 2 to 6 layers, and the winding angle is 3° for each layer from the inside to the outside. The angle of ~5° is gradually increased, and controlled so that the thickness of the final cured intermediate reinforcement layer accounts for more than 75% of the overall pipe wall thickness; (d) Preparation of the outer protective layer: directly spray anti-corrosion, waterproof and radiation-proof materials on the outer surface of the middle reinforcing layer, and finally form the bamboo winding composite pipe product with the required small-caliber specification. 8. A small-diameter bamboo winding composite pipe is characterized in that the inner hole diameter of the bamboo winding composite pipe is below 200mm, and comprises an inner liner, a middle reinforcing layer and an outer protective layer successively from the inside to the outside, wherein: The inner lining layer is made by curing fiber felt impregnated with adhesive, and forms an anti-seepage and smooth inner wall; The middle reinforcement layer is made of single bamboo strips adhered with resin, which are evenly wound and solidified outside the inner lining layer, and its total thickness accounts for more than 75% of the overall pipe wall thickness, wherein the bamboo strips The specifications and dimensions are set to be 2 mm to 10 mm wide and 0.6 mm to 1.2 mm thick, and are wound in a spiral manner relative to the inner lining layer during the entire winding process. The number of winding layers of bamboo strips in the middle reinforcement layer is 2 to 6 layers, and the winding angle gradually increases from the inside to the outside; for the middle reinforcement layer, the minimum winding angle is set to 20°, and the angle of each layer is 3° to 5° from the inside Incremental to the outside, until the maximum winding angle of 80°; in this way, the bamboo strips can be fully stretched during the whole spiral winding process, and at the same time, the axial strength and toughness characteristics of its bamboo fiber can be gradually expanded. Spread evenly to multiple directions of the pipe wall, and play a complementary role in stress at multiple angles; The outer protective layer is directly coated and cured on the outer surface of the middle reinforcement layer, and plays the role of waterproof, anticorrosion and radiation protection. 9. The small-caliber bamboo winding composite pipe as claimed in claim 8, characterized in that the total thickness of the intermediate reinforcement layer is set to account for 85% to 90% of the overall pipe wall thickness. 10. The small-caliber bamboo winding composite pipe as claimed in claim 8, characterized in that, in the above-mentioned intermediate reinforcement layer, besides the bamboo sheet and the resin, bio-based fillers and curing agents are also added, wherein the resin, bio The mass parts between the base filler and the curing agent are set to 100:10～15:2～5, and they are mixed together and then poured and adhered to the bamboo strips; wherein the resin is selected from One of polyurethane resin, phenolic resin, urea-formaldehyde resin or epoxy resin; the bio-based filler is selected from bamboo, wood, hemp, straw or plant husk, and its average mesh number is set to 20-80. 11. The small-diameter bamboo winding composite pipe as claimed in claim 8, characterized in that, the cross-sectional shape of the bamboo strips is processed into a rectangle, the moisture content is 8% to 15%, and the gap between adjacent bamboo strips is The degree of overlapping overlap in the length direction does not exceed 2mm. 12. The small-diameter bamboo winding composite pipe according to any one of claims 8-11, characterized in that, for the above-mentioned inner lining layer, its thickness is 0.5 mm to 1.5 mm, and it includes a second inner liner from the inside to the outside. an inner liner and a second inner liner, wherein the thickness of the first inner liner is smaller than that of the second inner liner, and the resin adhesion amount of the first inner liner is set to be greater than that of the second inner liner Floor. 13. The small-diameter bamboo winding composite pipe according to claim 12, characterized in that the first inner lining layer is 80g/m ² -120g/m ² , and the dipping rate of the adhesive is greater than 90%. Bamboo fiber felt, the second inner lining layer is made of bamboo fiber felt with a weight of 180g/m ² -250g/m ² and an adhesive impregnation rate greater than 75%. 14. The small-caliber bamboo winding composite pipe as claimed in claim 13, characterized in that, the bamboo yellow removal thickness of the above-mentioned bamboo strips is set to 0.2mm to 0.4mm, and the bamboo green removal thickness is set to 0.1mm to 0.4mm. 0.3mm. 15. A method for manufacturing a small-caliber bamboo winding composite pipe, characterized in that the method may further comprise the steps: (a) Cutting of bamboo strips: cut the original bamboo into multiple sections along its length, and remove the bamboo green on the outer surface and the bamboo yellow on the inner surface of each section, and the thickness of the bamboo yellow removal is set to 0.2 mm～0.4mm, the thickness of the bamboo green removal is set to 0.1mm～0.3mm, and correspondingly a plurality of bamboo strips with a rectangular cross section, a width of 2mm～10mm, and a thickness of 0.6mm～1.2mm are produced; (b) Preparation of the inner lining layer: on the straight pipe mold, a fiber felt adhered with anti-corrosion resin is used to make an inner lining layer with a thickness of 0.5 mm to 1.5 mm, and an anti-seepage and smooth inner wall is formed; (c) Preparation of the middle reinforcing layer: the prepared bamboo strips are unwound on a winding machine, and a plurality of strips pass through the resin tank and coated with resin, and then each single bamboo strip is spirally wound with respect to the inner lining layer from beginning to end. The method is to wind multiple layers evenly on it until the intermediate reinforcement layer of the required thickness is completed; in this process, the number of winding layers of the bamboo strips is 2 to 6 layers, and the winding angle is 3° for each layer from the inside to the outside. The angle of ~ 5 ° is gradually increased, and the thickness of the intermediate reinforcing layer that is finally cured is controlled to account for more than 75% of the overall tube wall thickness; for the above step (c), the minimum winding angle of the bamboo strips is 20 ° , and gradually increase from inside to outside according to the angle of 3°～5° for each layer, until it increases to the maximum winding angle of 80°; (d) Preparation of the outer protective layer: directly spray anti-corrosion, waterproof and radiation-proof materials on the outer surface of the middle reinforcing layer, and finally form the bamboo winding composite pipe product with the required small-caliber specification. 16. A small-diameter bamboo winding composite pipe, characterized in that the inner hole diameter of the bamboo winding composite pipe is below 200mm, and includes an inner liner, a middle reinforcement layer and an outer protective layer sequentially from the inside to the outside, wherein: The inner lining layer is made by curing fiber felt impregnated with adhesive, and forms an anti-seepage and smooth inner wall; The middle reinforcement layer is made of single bamboo strips adhered with resin, which are evenly wound and solidified outside the inner lining layer, and its total thickness accounts for more than 75% of the overall pipe wall thickness, wherein the bamboo strips The specifications and dimensions are set to be 2 mm to 10 mm wide and 0.6 mm to 1.2 mm thick, and are wound in a spiral manner relative to the inner lining layer during the entire winding process. The number of winding layers of bamboo strips in the middle reinforcement layer is 2 to 6 layers, and the winding angle gradually increases from the inside to the outside; in this way, the bamboo strips can be fully stretched during the entire spiral winding process, and at the same time, its axial strength and toughness characteristics of bamboo fibers It can gradually and evenly spread to multiple directions of the pipe wall, and play a complementary role in stress at multiple angles; In addition to bamboo strips and resin, bio-based fillers and curing agents are also added to the above-mentioned intermediate reinforcement layer, wherein the mass fraction between the resin, bio-based fillers and curing agent is set to 100:10 ~ 15:2 ~ 5, and mixed together and then poured and adhered to the bamboo strips; wherein, the resin is selected from one of polyurethane resin, phenolic resin, urea-formaldehyde resin or epoxy resin; the biological The base filler is selected from bamboo, wood, hemp, straw or plant husk, and its average mesh number is set to 20-80; The outer protective layer is directly coated and cured on the outer surface of the middle reinforcement layer, and plays the role of waterproof, anticorrosion and radiation protection. 17. The small-diameter bamboo winding composite pipe as claimed in claim 16, characterized in that the total thickness of the intermediate reinforcement layer is set to account for 85% to 90% of the overall pipe wall thickness. 18. The small-diameter bamboo winding composite pipe as claimed in claim 16, characterized in that, the cross-sectional shape of the bamboo strips is processed into a rectangle, the moisture content is 8% to 15%, and the gap between adjacent bamboo strips is The degree of overlapping overlap in the length direction does not exceed 2mm. 19. The small-diameter bamboo winding composite pipe according to any one of claims 16-18, characterized in that, for the above-mentioned inner lining layer, its thickness is 0.5 mm to 1.5 mm, and it includes a second inner liner from the inside to the outside. an inner liner and a second inner liner, wherein the thickness of the first inner liner is smaller than that of the second inner liner, and the resin adhesion amount of the first inner liner is set to be greater than that of the second inner liner Floor. 20. The small-diameter bamboo winding composite pipe according to claim 19, characterized in that, the first inner lining layer is 80g/m ² -120g/m ² , and the dipping rate of the adhesive is greater than 90%. Bamboo fiber felt, the second inner lining layer is made of bamboo fiber felt with a weight of 180g/m ² -250g/m ² and an adhesive impregnation rate greater than 75%. 21. The small-diameter bamboo winding composite pipe as claimed in claim 20, characterized in that, the bamboo yellow removal thickness of the above-mentioned bamboo strips is set at 0.2 mm to 0.4 mm, and the bamboo green removal thickness is set at 0.1 mm to 0.1 mm. 0.3mm. 22. A method for manufacturing a small-caliber bamboo winding composite pipe, characterized in that the method comprises the following steps: (a) Cutting of bamboo strips: cut the original bamboo into multiple sections along its length, and remove the bamboo green on the outer surface and the bamboo yellow on the inner surface of each section, and the thickness of the bamboo yellow removal is set to 0.2 mm～0.4mm, the thickness of the bamboo green removal is set to 0.1mm～0.3mm, and correspondingly a plurality of bamboo strips with a rectangular cross section, a width of 2mm～10mm, and a thickness of 0.6mm～1.2mm are produced; (b) Preparation of the inner lining layer: on the straight pipe mold, a fiber felt adhered with anti-corrosion resin is used to make an inner lining layer with a thickness of 0.5 mm to 1.5 mm, and an anti-seepage and smooth inner wall is formed; (c) Preparation of the middle reinforcing layer: the prepared bamboo strips are unwound on a winding machine, and a plurality of strips pass through the resin tank and coated with resin, and then each single bamboo strip is spirally wound with respect to the inner lining layer from beginning to end. The method is to wind multiple layers evenly on it until the intermediate reinforcement layer of the required thickness is completed; in this process, the number of winding layers of the bamboo strips is 2 to 6 layers, and the winding angle is 3° for each layer from the inside to the outside. The angle of ~5° is gradually increased, and controlled so that the thickness of the final cured intermediate reinforcement layer accounts for more than 75% of the overall tube wall thickness; in addition to bamboo strips and resin, bio-based fillers and Curing agent, wherein the mass parts between the resin, the bio-based filler and the curing agent are set to 100:10～15:2～5, and are mixed together and then poured and adhered to the bamboo strips above; wherein, the resin is selected from one of polyurethane resin, phenolic resin, urea-formaldehyde resin or epoxy resin; the bio-based filler is selected from bamboo, wood, hemp, straw or plant husk, and its average mesh The number is set to 20~80; (d) Preparation of the outer protective layer: directly spray anti-corrosion, waterproof and radiation-proof materials on the outer surface of the middle reinforcing layer, and finally form the bamboo winding composite pipe product with the required small-caliber specification. 23. A small-diameter bamboo winding composite pipe, characterized in that the inner hole diameter of the bamboo winding composite pipe is below 200mm, and includes an inner liner, a middle reinforcing layer and an outer protective layer sequentially from the inside to the outside, wherein: The inner lining layer is made by curing non-woven fabric soaked in adhesive, and forms an anti-seepage and smooth inner wall; The middle reinforcement layer is made of single bamboo strips adhered with resin, which are evenly wound and solidified outside the inner lining layer, and its total thickness accounts for more than 75% of the overall pipe wall thickness, wherein the bamboo strips The specifications and dimensions are set to be 2 mm to 10 mm wide and 0.6 mm to 1.2 mm thick, and are wound in a spiral manner relative to the inner lining layer during the entire winding process. The number of winding layers of bamboo strips in the middle reinforcement layer is 2 to 6 layers, and the winding angle gradually increases from the inside to the outside; in this way, the bamboo strips can be fully stretched during the entire spiral winding process, and at the same time, its axial strength and toughness characteristics of bamboo fibers It can gradually and evenly spread to multiple directions of the pipe wall, and play a complementary role in stress at multiple angles; The outer protective layer is directly coated and cured on the outer surface of the middle reinforcement layer, and plays the role of waterproof, anticorrosion and radiation protection. 24. The small-diameter bamboo winding composite pipe as claimed in claim 23, characterized in that, for the middle reinforcing layer, its minimum winding angle is set to 20°, and each layer is 3°～5° The angle increases successively from the inside to the outside until it reaches the maximum winding angle of 80°. 25. The small-caliber bamboo winding composite pipe as claimed in claim 23, characterized in that the total thickness of the intermediate reinforcement layer is set to account for 85% to 90% of the overall pipe wall thickness. 26. The small-caliber bamboo winding composite pipe as claimed in claim 23, characterized in that, in the above-mentioned intermediate reinforcement layer, besides the bamboo sheet and the resin, bio-based fillers and curing agents are also added, wherein the resin, bio The mass parts between the base filler and the curing agent are set to 100:10～15:2～5, and they are mixed together and then poured and adhered to the bamboo strips; wherein the resin is selected from One of polyurethane resin, phenolic resin, urea-formaldehyde resin or epoxy resin; the bio-based filler is selected from bamboo, wood, hemp, straw or plant husk, and its average mesh number is set to 20-80. 27. The small-diameter bamboo winding composite pipe as claimed in claim 23, characterized in that, the cross-sectional shape of the bamboo strips is processed into a rectangle, the moisture content is 8% to 15%, and the gap between adjacent bamboo strips is The degree of overlapping overlap in the length direction does not exceed 2mm. 28. The small-diameter bamboo winding composite pipe according to any one of claims 23-27, characterized in that, for the above-mentioned inner lining layer, its thickness is 0.5mm-1.5mm, and it includes a second an inner liner and a second inner liner, wherein the thickness of the first inner liner is smaller than that of the second inner liner, and the resin adhesion amount of the first inner liner is set to be greater than that of the second inner liner Floor. 29. The small-diameter bamboo winding composite pipe according to claim 28, characterized in that, the first inner lining layer is 80g/m ² -120g/m ² , and the dipping rate of the adhesive is greater than 90%. Bamboo fiber non-woven fabrics, the second inner lining layer adopts bamboo fiber non-woven fabrics of 180g/m ² -250g/m ² , and the impregnation rate of the adhesive is greater than 75%. 30. The small-caliber bamboo winding composite pipe as claimed in claim 29, characterized in that, the bamboo yellow removal thickness of the above-mentioned bamboo strips is set at 0.2 mm to 0.4 mm, and the bamboo green removal thickness is set at 0.1 mm to 0.1 mm. 0.3mm. 31. A method for manufacturing a small-diameter bamboo winding composite pipe, characterized in that the method comprises the following steps: (a) Cutting of bamboo strips: cut the original bamboo into multiple sections along its length, and remove the bamboo green on the outer surface and the bamboo yellow on the inner surface of each section, and the thickness of the bamboo yellow removal is set to 0.2 mm～0.4mm, the thickness of the bamboo green removal is set to 0.1mm～0.3mm, and correspondingly a plurality of bamboo strips with a rectangular cross section, a width of 2mm～10mm, and a thickness of 0.6mm～1.2mm are produced; (b) Preparation of the inner lining layer: the inner lining layer with a thickness of 0.5 mm to 1.5 mm is made on the straight pipe mold with a non-woven fabric adhered with an anti-corrosion resin, and an anti-seepage and smooth inner wall is formed; (c) Preparation of the middle reinforcing layer: the prepared bamboo strips are unwound on a winding machine, and a plurality of strips pass through the resin tank and coated with resin, and then each single bamboo strip is spirally wound with respect to the inner lining layer from beginning to end. The method is to wind multiple layers evenly on it until the intermediate reinforcement layer of the required thickness is completed; in this process, the number of winding layers of the bamboo strips is 2 to 6 layers, and the winding angle is 3° for each layer from the inside to the outside. The angle of ~5° is gradually increased, and controlled so that the thickness of the final solidified intermediate reinforcement layer accounts for more than 75% of the overall pipe wall thickness; (d) Preparation of the outer protective layer: directly spray anti-corrosion, waterproof and radiation-proof materials on the outer surface of the middle reinforcing layer, and finally form the bamboo winding composite pipe product with the required small-caliber specification. 32. A small-diameter bamboo winding composite pipe, characterized in that the diameter of the inner hole of the bamboo winding composite pipe is less than 200mm, and includes an inner liner, a middle reinforcing layer and an outer protective layer from the inside to the outside, wherein: The inner lining layer is made of fiber felt impregnated with adhesive, and forms an impermeable and smooth inner wall; The middle reinforcement layer is made of single bamboo strips adhered with resin, which are evenly wound and solidified outside the inner lining layer, and its total thickness accounts for more than 75% of the overall pipe wall thickness, wherein the bamboo strips The specification size is set as a width greater than or equal to 2mm and less than 10mm, and a thickness of 0.6mm to 1.2mm, and the inner liner is wound in a spiral manner during the entire winding process, and the bamboo strips of the middle reinforcement layer are wound The number of layers is 2-6 layers, and the winding angle gradually increases from the inside to the outside; in this way, the bamboo strips can be fully stretched during the whole spiral winding process, and at the same time, the axial strength of its bamboo fibers And toughness characteristics can be gradually and evenly spread to multiple directions of the pipe wall, and play a role of stress complementation at multiple angles; The outer protection layer is directly coated and cured on the outer surface of the middle reinforcement layer, and plays the role of waterproof, anticorrosion and radiation protection. 33. The small-caliber bamboo winding composite pipe as claimed in claim 32, characterized in that the total thickness of the intermediate reinforcement layer is set to account for 85% to 90% of the wall thickness of the overall pipe. 34. The small-caliber bamboo winding composite pipe as claimed in claim 32, characterized in that, in the above-mentioned intermediate reinforcement layer, besides bamboo sheets and resin, bio-based fillers and curing agents are also added, wherein the resin, bio The mass parts between the base filler and the curing agent are set to 100:10～15:2～5, and they are mixed together and then poured and adhered to the bamboo strips; wherein the resin is selected from One of polyurethane resin, phenolic resin, urea-formaldehyde resin or epoxy resin; the bio-based filler is selected from bamboo, wood, hemp, straw or plant husk, and its average mesh number is set to 20-80. 35. The small-diameter bamboo winding composite pipe as claimed in claim 32, characterized in that, the cross-sectional shape of the bamboo strips is processed into a rectangle, the moisture content is 8% to 15%, and the gap between adjacent bamboo strips is The degree of overlapping overlap in the length direction does not exceed 2mm. 36. The small-diameter bamboo winding composite pipe as claimed in claim 32, characterized in that, for the middle reinforcement layer, the minimum winding angle is set to 20°, and each layer is 3°～5° The angle increases successively from the inside to the outside until it reaches the maximum winding angle of 80°. 37. The small-diameter bamboo winding composite pipe according to any one of claims 32-36, characterized in that, for the above-mentioned inner lining layer, its thickness is 0.5 mm to 1.5 mm, and it includes a second layer from the inside to the outside. an inner liner and a second inner liner, wherein the thickness of the first inner liner is smaller than that of the second inner liner, and the resin adhesion amount of the first inner liner is set to be greater than that of the second inner liner Floor. 38. The small-diameter bamboo winding composite pipe according to claim 37, characterized in that the first inner lining layer is 80g/m ² -120g/m ² , and the dipping rate of the adhesive is greater than 90%. Bamboo fiber felt, the second inner lining layer is made of bamboo fiber felt with a weight of 180g/m ² -250g/m ² and an adhesive impregnation rate greater than 75%. 39. The small-caliber bamboo winding composite pipe as claimed in claim 38, characterized in that, the bamboo yellow removal thickness of the above-mentioned bamboo strips is set to 0.2 mm to 0.4 mm, and the bamboo green removal thickness is set to 0.1 mm to 0.4 mm. 0.3mm. 40. A method for manufacturing a small-diameter bamboo winding composite pipe, characterized in that the method comprises the following steps: (a) Cutting of bamboo strips: cut the original bamboo into multiple sections along its length, and remove the bamboo green on the outer surface and the bamboo yellow on the inner surface of each section, and the thickness of the bamboo yellow removal is set to 0.2 mm～0.4mm, the thickness of the bamboo green removal is set to 0.1mm～0.3mm, and correspondingly a plurality of bamboo strips with a rectangular cross section, a width greater than or equal to 2mm and less than 10mm, and a thickness of 0.6mm～1.2mm are produced; (b) Preparation of the inner lining layer: on the straight pipe mold, a fiber felt adhered with anti-corrosion resin is used to make an inner lining layer with a thickness of 0.5 mm to 1.5 mm, and an anti-seepage and smooth inner wall is formed; (c) Preparation of the middle reinforcing layer: the prepared bamboo strips are unwound on a winding machine, and a plurality of strips pass through the resin tank and coated with resin, and then each single bamboo strip is spirally wound with respect to the inner lining layer from beginning to end. The method is to wind multiple layers evenly on it until the intermediate reinforcement layer of the required thickness is completed; in this process, the number of winding layers of the bamboo strips is 2 to 6 layers, and the winding angle is 3° for each layer from the inside to the outside. The angle of ~5° is gradually increased, and controlled so that the thickness of the final solidified intermediate reinforcement layer accounts for more than 75% of the overall pipe wall thickness; (d) Preparation of the outer protective layer: directly spray anti-corrosion, waterproof and radiation-proof materials on the outer surface of the middle reinforcing layer, and finally form the bamboo winding composite pipe product with the required small-caliber specification.