A BFMH basalt fiber multilayer structure high-pressure composite pipe

Abstract

The present invention relates to the field of solid slurry pipelines, and provides a BFMH basalt fiber multilayer structure high-pressure composite pipe. The pipeline includes a metal inner layer and an outer composite fiber composite material layer, wherein the thickness of the metal inner layer at both ends gradually becomes thicker, forming a gradually thick wall-thin wall-gradually thick wall structure. The composite fiber composite material layer can adopt high-performance fibers such as basalt fiber or glass fiber, and is coated with an anti-ultraviolet layer or a basalt fiber composite material anti-ultraviolet layer. Metal flanges are provided at both ends of the metal inner layer, and a wear-resistant layer is also provided inside, extending to the flange connection end face to form a flange end face connection layer. The present invention aims to solve the problems of existing metal pipes being too heavy and having insufficient pressure resistance, and to improve the transportation efficiency and safety of the mining industry. The present invention can be used to transport ore slurry, hot water, hydrogen, air, etc.

Description

Technical Field

[0001] This invention relates to the field of solid slurry pipelines and provides a BFMH basalt fiber multilayer high-pressure composite pipe. Background Technology

[0002] With the rapid development of the mining industry, solid slurry pipelines, as key equipment for conveying crushed stone in mines, have received widespread attention for their performance and efficiency. Currently, most solid slurry pipelines on the market are made of metal, which to some extent meets the conveying requirements, but also exposes many shortcomings.

[0003] First, the wall thickness of existing metal pipes is typically around 12 millimeters, making the pipes excessively heavy. In complex environments such as mines, installation and transportation become extremely difficult, increasing labor costs and extending construction periods. To reduce pipe weight, some manufacturers have attempted to reduce the wall thickness; however, this approach leads to a significant decrease in the pipe's pressure resistance, failing to meet high-pressure transmission requirements and posing safety hazards.

[0004] Furthermore, metal pipelines are susceptible to corrosion and wear during long-term use, further affecting their service life and transport efficiency. Therefore, developing a new type of solid slurry pipeline that is lightweight, pressure-resistant, and corrosion-resistant has become an urgent problem to be solved in the mining industry.

[0005] In summary, existing solid slurry pipelines suffer from drawbacks such as excessive pipe weight and insufficient pressure resistance, failing to meet the demands of modern mining for efficient, safe, and convenient transportation. This invention aims to provide a novel solid slurry pipeline to address these technical problems and improve transportation efficiency and safety in the mining industry. Summary of the Invention

[0006] The purpose of this invention is to ensure that the overall strength of the pipeline still meets the pressure resistance requirements by reducing the thickness of the metal inner layer and wrapping the metal inner layer with a basalt braided layer. The thickness of the metal inner layer of the entire pipeline is reduced. Then, when the basalt braided layer is wrapped, there will be a cross section at the junction of the basalt and the flange. This cross section cannot meet the pressure resistance requirements.

[0007] To achieve the above objectives, the present invention employs the following technical means:

[0008] This invention provides a BFMH (BF-basalt fiber, M-multilayer structure, H-high pressure) basalt fiber multilayer structure high pressure composite pipe, which includes a metal inner layer and an outer composite fiber braided layer. The metal inner layer has a gradually thickening thickness at both ends, forming a gradually thickened wall-thinned wall-gradiently thickened wall structure.

[0009] In the above scheme, the composite fiber braided layer uses basalt fiber.

[0010] In the above scheme, the composite fiber braided layer is made of glass fiber, and the composite fiber braided layer is coated with a UV-resistant layer.

[0011] In the above scheme, metal flanges are provided at both ends of the inner metal layer, and the flange structure can form a better seal and better pressure resistance.

[0012] In the above scheme, a wear-resistant layer is also provided inside the metal inner layer.

[0013] In the above scheme, a wear-resistant layer is also provided inside the metal inner layer, extending to the flange connection end face to form a flange end face connection layer.

[0014] Because the present invention employs the above-mentioned technical means, it has the following beneficial effects:

[0015] 1. The pipe used in this invention has a gradually thickened wall structure, which enables an effective strength transition between the basalt braided layer and the metal layer, ensuring that there are no weak points in the pipe's resistance and thus meeting the pressure resistance requirements.

[0016] 2. The addition of a wear-resistant layer increases wear resistance. Examples of wear-resistant materials include high-density polyethylene, tetrafluoroethylene, polyurethane, nylon, and polyimide. Attached Figure Description

[0017] Figure 1 This is a structural diagram of the present invention;

[0018] Figure 2 This is a partial view of the present invention;

[0019] Figure 3 This is a diagram illustrating the defects of existing technologies. Detailed Implementation

[0020] The embodiments of the present invention will be described in detail below. Although the present invention will be described and illustrated in conjunction with some specific embodiments, it should be noted that the present invention is not limited to these embodiments. On the contrary, any modifications or equivalent substitutions made to the present invention should be covered within the scope of the claims of the present invention.

[0021] Furthermore, to better illustrate the present invention, numerous specific details are set forth in the following detailed embodiments. Those skilled in the art will understand that the present invention can be practiced without these specific details.

[0022] The purpose of this invention is to ensure that the overall strength of the pipeline still meets the pressure resistance requirements while reducing the thickness of the metal inner layer by covering it with a basalt braided layer. The thickness of the entire pipeline's metal inner layer is reduced. Then, when covering it with the basalt braided layer, a cross-section exists at the junction of the basalt braided layer and the flange, such as... Figure 3 As shown in section A, because the metal and composite fiber composite material layer on the flange face cannot be bonded, this cross section cannot meet the pressure resistance requirements when subjected to radial shear force from inside the pipe.

[0023] A BFMH basalt fiber multilayer high-pressure composite pipe includes a metal inner layer 1 and an outer composite fiber braided layer 2. The metal inner layer has a gradually thickening end, forming a gradually thickened wall 1-1-thinned wall 1-2-gradiently thickened wall 1-1 structure.

[0024] In the above scheme, the composite fiber braided layer 2 is made of basalt fiber.

[0025] In the above scheme, the composite fiber braided layer 2 is made of glass fiber or other high-performance fibers (carbon fiber, aramid fiber, ultra-high molecular weight polyethylene fiber, PBO fiber, polyamide fiber, polyester fiber, etc.), and the composite fiber braided layer 2 is coated with an anti-ultraviolet layer (or an anti-ultraviolet layer of basalt fiber composite material).

[0026] In the above scheme, metal flanges 3 are provided at both ends of the inner metal layer.

[0027] In the above scheme, a wear-resistant layer 4 is also provided inside the metal inner layer.

[0028] In the above scheme, a wear-resistant layer 4 is also provided inside the metal inner layer, extending to the flange connection end face 3-1 to form the flange end face connection layer 4-1.

[0029] I. Material Properties and Structural Design

[0030] Basalt fiber composite layer:

[0031] Strength: σ1 = 400MPa

[0032] Thickness: d1

[0033] Design considerations: As the main load-bearing layer, it provides high strength and lightweight characteristics.

[0034] Steel pipe metal layer (support layer):

[0035] Strength: σ² = 200 MPa

[0036] Thickness: d2

[0037] Design considerations: to provide structural stability and partial load-bearing capacity, forming a composite reinforced structure with the basalt fiber layer.

[0038] Functional layer (wear-resistant, corrosion-resistant):

[0039] Thickness: d3

[0040] Design considerations: Enhance the pipe's wear and corrosion resistance to extend its service life.

[0041] II. Interface Features

[0042] Interfacial shear strength between basalt fiber composite layer and steel pipe metal layer: τ1 ~ 10MPa

[0043] Design considerations: Ensure that the interface does not fail when subjected to shear force and guarantee strong interlayer bonding.

[0044] III. Design Requirements and Calculations

[0045] Working pressure and diameter:

[0046] Work pressure: P

[0047] Diameter: D

[0048] Safety factor: a (taken as 2)

[0049] Structural dimensional relationships:

[0050] Transition surface L2: d2 ≤ L2 ≤ 3d2

[0051] Bonding surface L1: L1≥ σ2 / τ1× d2~ 20d2

[0052] Basalt fibrous layer thickness: d1 ≥ 1.2 × σ2 / σ1 × d2 ~ 0.6d2

[0053] Functional layer thickness d3: Material wear coefficient × safety factor a × service life

[0054] Flange thickness: d5 ≥ 2d2

[0055] The thickness d4 of the thin metal layer in the steel pipe: 2mm ≤ d4 ≤ 0.3d2

[0056] The thickness d2 of the metal layer in the steel pipe is: d2 = a × D × P / (2 × σ2)

[0057] Example calculation:

[0058] When P = 10 MPa and D = 400 mm, d² = 10 mm

[0059] When P = 5MPa and D = 400mm, d2 = 5mm

[0060] When P = 3MPa and D = 400mm, d2 = 3mm

[0061] IV. Analysis and Optimization

[0062] Interface Length Analysis: The composite fiber reinforced pipe provided by this invention employs unique design and technical means to ensure the overall strength and pressure resistance of the pipeline. Specifically, the thickness of the inner metal layer is optimized and reduced, and the strength is compensated by the outer composite fiber braided layer (such as basalt fiber or glass fiber), thus meeting the pressure resistance requirements even with a reduced metal layer thickness. However, it is worth noting that the design of the bonding interface must meet a specific length requirement L1 to ensure that it does not fail under shear force. This is because the bonding interface can only withstand shear force and is not allowed to withstand tensile force; if the interface length is insufficient, the interface may fail under longitudinal tensile force, failing to reach the tensile strength level of the metal. Therefore, this invention, through precise calculation and design, ensures that the interface is long enough to achieve equivalent strength to the metal layer, thereby avoiding the cross-section at the basalt and flange connection becoming a weak point in the pressure resistance, ensuring the overall pressure resistance and safety of the pipe.

[0063] Structural optimization: By adjusting the thickness and material properties of each layer, the overall structural performance is optimized to meet multiple requirements such as pressure resistance, wear resistance, and corrosion resistance.

[0064] V. Characteristics

[0065] Gradual thick-walled structure: The inner metal layer adopts a gradual thick-walled-thin-gradual thick-walled structure to achieve a smooth transition in strength and avoid weak points in the resistance.

[0066] Flanges and wear-resistant layer: Flanges are installed at both ends of the inner metal layer, and a wear-resistant layer is added inside and extends to the flange connection face to form a flange end face connection layer, which enhances sealing and pressure resistance.

[0067] VI. Implementation Results

[0068] Strength and pressure resistance: Through composite fiber reinforcement and a gradually thickened wall design, the pipes still meet pressure resistance requirements even with a reduced metal layer thickness.

[0069] Wear and corrosion resistance: The functional layer significantly improves the wear and corrosion resistance of the pipeline.

[0070] Lightweight and convenient: Compared with traditional metal pipes, this invention significantly reduces the weight of the pipe, making it easier to install and transport, and improving construction efficiency.

Claims

1. A BFMH basalt fiber multilayer high-pressure composite pipe, characterized in that, It includes a metal inner layer (1) and an outer composite fiber braided layer (2). The metal inner layer has a gradually thickening thickness at both ends, forming a gradually thickened wall (1-1)-thin wall (1-2)-gradually thickened wall (1-1) structure. The composite fiber braided layer (2) is made of basalt fiber. Metal flanges (3) are provided at both ends of the metal inner layer. There will be a cross section at the junction of the basalt braided layer and the flange. The portion of the inner metal layer where the thickness gradually increases at both ends is the transition surface L2: d2 ≤ L2 ≤ 3d2; The thick-walled portion of the gradually thickened wall (1-1) is the bonding surface L1: L1≥ σ2 / τ1 × d2 ~ 20d2; Basalt fibrous layer thickness d1: d1 ≥ 1.2 × σ2 / σ1 × d2 ~ 0.6d2; Flange thickness: d5 ≥ 2d2; The thickness d4 of the thin metal layer in the steel pipe is: 2mm ≤ d4 ≤ 0.3d2; The thickness d2 of the metal layer in the steel pipe: d2 = a × D × P / (2 × σ2); Where P is the working pressure, D is the diameter, a is the safety factor, σ1 is the strength of the basalt fiber composite layer, σ2 is the strength of the steel pipe metal layer, and d3 is the thickness of the functional layer; τ1 is the interfacial shear strength between the basalt fiber composite layer and the steel pipe metal layer.

2. The BFMH basalt fiber multilayer high-pressure composite pipe according to claim 1, characterized in that, (2) The composite fiber woven layer is coated with an anti-ultraviolet layer.

3. A BFMH basalt fiber multilayer high-pressure composite pipe according to claim 1 or 2, characterized in that, A wear-resistant layer (4) is also provided inside the metal inner layer.

4. The BFMH basalt fiber multilayer high-pressure composite pipe according to claim 3, characterized in that, A wear-resistant layer (4) is also provided inside the metal inner layer, extending to the flange connection end face (3-1) to form the flange end face connection layer (4-1).

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