High-strength wear-resistant frame embedded structure composite material scraper and preparation method thereof

Abstract

The application provides a high-strength wear-resistant frame embedded structure composite material scraper and a preparation method thereof, which comprises an alloy steel scraper frame and a composite material injection layer; the alloy steel scraper frame comprises a main body section, and axe head sections are arranged at both ends of the main body section; the axe head sections comprise upper surface sections and lower surface sections; the upper surface sections are arranged in horizontal straight sections, and rectangular cavities are arranged on the horizontal straight sections; the lower surface sections are arranged in inclined fan-shaped sections, and fan-shaped cavities are arranged on the inclined fan-shaped sections; the composite material injection layers are arranged in the rectangular cavities and the fan-shaped cavities. The application decouples the bearing and friction reduction functions, the high-strength alloy steel scraper frame bears the core traction and impact load, the composite material injection layers are embedded in the main wear contact surfaces of the alloy steel scraper frame, the friction pair is changed from "steel-steel" to "steel-composite material", the contact friction coefficient of the wear contact surface is reduced, and the service life of the scraper and the matched chute chain channel is prolonged.

Description

Technical Field

[0001] This invention relates to the field of scraper conveying equipment technology, and in particular to a high-strength wear-resistant frame-interlocking composite material scraper and its preparation method. Background Technology

[0002] As the "main artery" of coal flow in fully mechanized coal mining faces, scraper conveyor equipment's operational reliability and economy directly constrain coal mining efficiency and costs. As the core actuator of the equipment's chain drive system, the scraper bears the traction load of the chain and the reaction force of the material during operation. It operates under harsh conditions of heavy load, low speed, strong impact, and high abrasive wear. These conditions require the scraper to possess sufficient strength and toughness to resist bending and impact, while also exhibiting excellent friction-reducing and wear-resistant properties to extend the life of the friction pair. However, traditional forged or cast alloy steel scrapers have long faced a trade-off between strength and wear resistance. Increasing hardness enhances wear resistance but reduces toughness and increases the risk of fracture; increasing cross-sectional dimensions improves rigidity but leads to increased weight and frictional power consumption. This contradiction becomes increasingly prominent against the backdrop of coal mining equipment development towards higher conveying capacities, longer working faces, and higher chain speeds.

[0003] The scraper assembly mainly consists of a scraper, pressure plate, bolts, nuts, and chain. The middle connecting section of the scraper is primarily used to engage with the chain's flat ring, and then secured with the pressure plate, bolts, and nuts to form a unified whole. The scraper's left and right ends are mainly used to push materials along the chute. With the increasing transport capacity of scraper conveyor equipment, the working load of the scraper assembly has also increased significantly. To ensure the reliability and service life of the scraper assembly, the scrapers used in existing heavy-duty scraper conveyor equipment are generally designed as solid, irregularly shaped columnar forgings or castings to improve the scraper's strength and rigidity, preventing deformation and breakage after wear. Summary of the Invention

[0004] The present invention aims to at least partially solve one of the technical problems in the related art.

[0005] To achieve the above objectives, the present invention proposes a high-strength wear-resistant frame-interlocking composite material scraper, comprising an alloy steel scraper frame and a composite material injection-molded layer;

[0006] The alloy steel scraper frame includes a main body section, with axe sections at both ends of the main body section, and a locking groove for engaging the chain on the main body section; the axe section includes an upper surface section and a lower surface section; The upper surface segment is configured as a horizontal straight segment, and a rectangular cavity is provided on the horizontal straight segment; The lower surface segment is configured as an inclined fan-shaped segment, and a fan-shaped cavity is provided on the inclined fan-shaped segment; Both the rectangular cavity and the fan-shaped cavity are provided with the composite material injection molding layer.

[0007] This invention decouples the load-bearing and friction-reducing functions, using a high-strength alloy steel scraper frame to bear the core traction and impact loads. At the same time, a composite material injection-molded layer is embedded in the main wear contact interface of the alloy steel scraper frame, transforming the friction pair from "steel-steel" to "steel-composite material". This reduces the contact friction coefficient of the wear contact surface, thereby extending the service life of the scraper itself and the matching chute chain.

[0008] Optionally, the inner wall and bottom of the rectangular cavity, and the inner wall and bottom of the fan-shaped cavity are all provided with dovetail grooves.

[0009] Furthermore, the composite material filling layer has an outwardly protruding edge on the side opposite to the bottom of the cavity. The outwardly protruding edge is set as an arc surface or a slope surface, and the protrusion height of the outwardly protruding edge is set to 2mm to 10mm.

[0010] Furthermore, the composite material used in the injection molding layer comprises a composite material of discontinuous fibers and a resin matrix.

[0011] Furthermore, the composite material used in the injection molding layer also includes one or more combinations of wear-resistant additives, flame retardants, anti-aging agents, and compatibilizers.

[0012] Furthermore, the main body section is provided with several positioning screw holes on both sides corresponding to the slot.

[0013] This invention also discloses a method for preparing a scraper for a high-strength wear-resistant frame-interlocking composite material, comprising the following steps: S1. The cavities of the alloy steel scraper frame are roughened by sandblasting and coated with a base adhesive layer. S2. Place the alloy steel scraper frame that has completed step S1 into a preheating furnace for preheating treatment to eliminate the cold mold effect. S3. Place the preheated alloy steel scraper frame into the lower mold and perform composite material injection molding; S4. Pressure holding and cooling: The composite material injection layer is cooled and formed in the cavity of the alloy steel scraper frame. After the buck teeth are cooled, the mold opening and demolding operations are carried out.

[0014] Furthermore, in step S2, when eliminating the cold mold effect, the temperature in the preheating furnace is heated to not less than 120°C and held at that temperature for at least 2 hours.

[0015] Furthermore, in S3, during composite material injection molding, the composite material is heated to a molten flow state of 150°C-170°C for injection molding.

[0016] Furthermore, during the pressure holding and cooling phase in S4, the pressure holding time is not less than 300 seconds.

[0017] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0018] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the following description of the embodiments taken in conjunction with the accompanying drawings, wherein: Figure 1 This is a schematic diagram of the overall structure of a high-strength wear-resistant frame-interlocking composite material scraper according to the present invention; Figure 2 This is a schematic diagram of the alloy steel scraper frame structure of a high-strength wear-resistant frame-interlocking composite material scraper according to the present invention. Figure 3 This is a schematic diagram from another perspective of the alloy steel scraper frame structure of a high-strength wear-resistant frame-interlocking composite material scraper according to the present invention. Figure 4 This is a front view schematic diagram of the alloy steel scraper frame structure of a high-strength wear-resistant frame-interlocking composite material scraper according to the present invention; Figure 5 This is a top view schematic diagram of the alloy steel scraper frame structure of a high-strength wear-resistant frame-interlocking composite material scraper according to the present invention. Figure 6 This is a schematic cross-sectional view of the alloy steel scraper frame of a high-strength wear-resistant frame-fitted composite material scraper according to the present invention. Figure 7 This is a cross-sectional schematic diagram of a high-strength wear-resistant frame-interlocking composite material scraper according to the present invention; Figure 8 This is a side view schematic diagram of a high-strength wear-resistant frame-interlocking composite material scraper according to the present invention.

[0019] Explanation of reference numerals in the attached figures: 100. Alloy steel scraper frame; 200. Composite material injection molding layer; 210. Outwardly protruding edge; 300. Main body section; 310. Locking groove; 320. Positioning screw hole; 400. Axe head section; 410. Horizontal straight section; 411. Rectangular cavity; 420. Inclined fan-shaped section; 421. Fan-shaped cavity. Detailed Implementation

[0020] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0021] This invention proposes a high-strength, wear-resistant frame-interlocking composite material scraper, as described below. Figures 1 to 8 Please provide a detailed explanation.

[0022] A high-strength, wear-resistant frame-interlocking composite material scraper includes an alloy steel scraper frame 100 and a composite material injection-molded layer 200. The alloy steel scraper frame 100 includes a main body section 300, with axe sections 400 at both ends of the main body section 300. The main body section 300 is provided with a locking groove 310 for engaging the chain. The axe section 400 includes an upper surface section and a lower surface section. The upper surface segment is set as a horizontal straight segment 410, and a rectangular cavity 411 is provided on the horizontal straight segment 410; The lower surface segment is configured as an inclined fan-shaped segment 420, and a fan-shaped cavity 421 is provided on the inclined fan-shaped segment 420; Both the rectangular cavity 411 and the fan-shaped cavity 421 are provided with a composite material injection molding layer 200.

[0023] This invention decouples the load-bearing and friction-reducing functions, using a high-strength alloy steel scraper frame 100 to bear the core traction and impact loads. At the same time, a composite material injection-molded layer 200 is embedded in the main wear contact interface of the alloy steel scraper frame 100. This not only ensures the structural safety of the scraper under extreme working conditions, but also transforms the friction pair from "steel-steel" to "steel-composite material", reducing the contact friction coefficient of the wear contact surface to below 0.15, thereby resulting in a reduction of about 2% in no-load power consumption, and thus extending the service life of the scraper itself and the matching chute chain.

[0024] Specifically, the rectangular cavity 411 has a length of 100mm, a depth of 40mm, and a width of 50mm, while the fan-shaped cavity 421 has a length of 50-70mm, a depth of 30mm, and a length of 120mm. During use, the composite material injection layer 200 in the rectangular cavity 411 and the fan-shaped cavity 421 will directly contact the steel contact surface within the scraper and chute chain track, thereby preventing the axe section 400 body from directly contacting the chute chain track. This reduces the friction coefficient of the contact surface, extending the service life of the scraper itself and the matching chute chain track.

[0025] To ensure sufficient contact between the composite injection-molded layer 200 and the chute chain track, the composite injection-molded layer 200 occupies more than 65% of the main wear contact area of ​​the scraper, transforming steel-steel friction into heterogeneous friction between steel and composite materials. This significantly reduces the friction coefficient from 0.20 to approximately 0.10–0.15, substantially decreasing contact temperature rise and adhesive wear tendency. Simultaneously, the new scraper's single-piece mass is 13% lower than that of a conventional cast scraper of the same specifications. The composite injection-molded layer 200 also reduces contact pressure, thus simultaneously alleviating wear on the chute chain track.

[0026] In some embodiments, considering that the bonding force between the composite material and the inner wall of the cavity is weak when the composite material injection layer 200 is directly injection molded into the rectangular cavity 411 or the fan-shaped cavity 421, the composite material injection layer 200 is prone to detaching from the rectangular cavity 411 or the fan-shaped cavity 421. Therefore, dovetail grooves are provided on the inner wall and bottom of the rectangular cavity 411, and on the inner wall and bottom of the fan-shaped cavity 421. During composite material injection molding, the molten composite material flows into the dovetail grooves until it fills the rectangular cavity 411 and the fan-shaped cavity 421. After the composite material cools, the composite material and the dovetail grooves form a wedge-shaped anchor effect, which effectively suppresses the debonding and peeling of the composite material injection layer 200 under impact load.

[0027] In other embodiments, in order to further enhance the cross-sectional bonding force of the rectangular cavity 411 and the fan-shaped cavity 421, a roughening layer is provided on the surface of the rectangular cavity 411 and the fan-shaped cavity 421. The roughening layer is formed by sandblasting roughening treatment, and the roughness Ra of the roughening layer is ≥12.5μm. Furthermore, a silane coupling agent coating layer is protruded outside the roughening layer to further enhance the cross-sectional bonding force through chemical bonding.

[0028] In some embodiments, the composite material filling layer has a convex edge 210 on the side facing away from the bottom of the cavity. The convex edge 210 is configured as an arc surface or a slope, and the protrusion height of the convex edge 210 is set to 2mm to 10mm. The convex edge 210 ensures that only the composite material contacts the chute chain track, avoiding direct contact between the axe section 400 of the alloy steel scraper frame 100 and the chute chain track, thus reducing friction. Furthermore, since the protrusion height has a certain range, it can provide sufficient wear space for the composite material injection layer 200, reducing the frequency of scraper replacement due to wear and reducing material waste.

[0029] In some embodiments, the composite material selected for the composite injection layer 200 comprises a composite material of discontinuous fibers and a resin matrix.

[0030] Specifically, discontinuous fibers refer to fibers with a limited length, which are relatively short compared to continuous fibers. In specific embodiments of the present invention, each discontinuous fiber is independently selected from at least one of glass fiber, carbon fiber, basalt fiber, aramid fiber, quartz fiber, and polyimide fiber.

[0031] The resin is set as a thermoplastic resin, specifically at least one of polyamide, polyethylene, polypropylene, polyurethane, polytetrafluoroethylene, polyoxymethylene, polycarbonate, polyphenylene sulfide, and polyaryletherketone. Among them, the types of polyaryletherketone include PEK, PEEK, and PEKK.

[0032] In one specific embodiment, the composite material uses ultra-high molecular weight polyethylene (UHMWPE) as the matrix. This material has a molecular weight exceeding 1.5 million, extremely low surface energy of its molecular chains, and weak adhesion to metallic materials. This results in an extremely low coefficient of dry friction (0.10–0.15) and excellent self-lubricating properties. The wear mechanism is primarily slight plastic plowing, making adhesion transfer less likely. Furthermore, a continuous lubricating film can be transferred to the grinding surfaces, further reducing the coefficient of friction. In addition, UHMWPE has a density of only 0.93–0.98 g / cm³, less than 1 / 8 that of steel, resulting in significant weight reduction benefits. It also exhibits excellent chemical stability, resistance to acids and alkalis, and moisture, making it suitable for complex downhole environments. This reduces the weight of a single scraper component by approximately 14%.

[0033] However, the yield strength (20-30 MPa) and elastic modulus (approximately 0.8 GPa) of pure polyethylene (UHMWPE) are far below the load-bearing requirements of scrapers, and it has a significant tendency to creep under long-term loads, making it unsuitable for use as a structural component alone. Therefore, 30% by mass of reinforcing fibers are added to improve compressive strength and creep resistance.

[0034] In some embodiments, the composite material used for the injection-molded composite layer 200 may also contain other additives, including one or more combinations of wear-resistant additives, flame retardants, anti-aging agents, and compatibilizers. These additives can enhance the wear resistance, anti-aging properties, and fire resistance of the composite material.

[0035] In some embodiments, a plurality of positioning screw holes 320 are provided on both sides of the main body segment 300 corresponding to the locking groove 310. The positioning screw holes 320 facilitate the worker to fix the main body segment 300 to the pressure plate.

[0036] This invention also discloses a method for preparing a scraper for a high-strength wear-resistant frame-interlocking composite material, comprising the following steps: S1. The cavities of the alloy steel scraper frame 100 are roughened by sandblasting and coated with a base adhesive layer. S2. Place the alloy steel scraper frame 100, which has completed step S1, into a preheating furnace for preheating treatment to eliminate the cold mold effect. S3. The preheated alloy steel scraper frame 100 is lowered into the mold and the composite material is injection molded. S4. Pressure holding and cooling are performed to allow the composite material injection layer 200 to cool and form within the cavity of the alloy steel scraper frame 100. After the buck teeth cooling is completed, the mold opening and demolding operations are carried out.

[0037] In some embodiments, during sandblasting roughening, the surface roughness of the cavity Ra ≥ 12.5 μm, and a silane coupling agent is used for coating the base coat to further enhance the cross-sectional bonding force through chemical bonding. In some embodiments, during S2, to eliminate the cold mold effect, the temperature in the preheating furnace is raised to not less than 120°C and held for at least 2 hours. This mitigates the rapid cooling effect caused by contact with cold metal after the high-temperature melt is injected, thereby improving the interfacial bonding strength between the composite material and the cavity wall.

[0038] In some embodiments, during S3, the preheated scraper frame is quickly placed into the mold, and then the composite material is injected. The composite material is heated to a molten flow state of 150°C-170°C for injection molding. The composite material completely fills the rectangular cavity 411 and the fan-shaped cavity 421, including the dovetail grooves inside each cavity. The mold has a pre-set molding cavity with an outer convex edge 210. During the injection molding process, the composite material needs to fill the molding cavity with the outer edge.

[0039] In some embodiments, during the pressure holding and cooling stage in S4, the pressure holding time is not less than 300s. This ensures that the molten composite material, under high pressure, not only completely fills the microstructure of the cavity but also penetrates deep into the mechanical interlocking parts such as the dovetail groove, forming a dense interlayer with a "wedge anchor" effect after solidification.

[0040] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0041] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0042] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0043] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0044] In this invention, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0045] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A high-strength, wear-resistant frame-interlocking composite material scraper, characterized in that, Includes an alloy steel scraper frame and a composite material injection-molded layer; The alloy steel scraper frame includes a main body section, with axe sections at both ends of the main body section, and a locking groove for engaging the chain on the main body section; the axe section includes an upper surface section and a lower surface section; The upper surface segment is configured as a horizontal straight segment, and a rectangular cavity is provided on the horizontal straight segment; The lower surface segment is configured as an inclined fan-shaped segment, and a fan-shaped cavity is provided on the inclined fan-shaped segment; Both the rectangular cavity and the fan-shaped cavity are provided with the composite material injection molding layer.

2. The high-strength wear-resistant frame-interlocking composite material scraper as described in claim 1, characterized in that, The inner wall and bottom of the rectangular cavity, as well as the inner wall and bottom of the fan-shaped cavity, are all provided with dovetail grooves.

3. The high-strength wear-resistant frame-interlocking composite material scraper as described in claim 1, characterized in that, The composite material filling layer has a convex edge on the side away from the bottom of the cavity. The convex edge is set as an arc surface or a slope surface, and the protrusion height of the convex edge is set to 2mm to 10mm.

4. The high-strength wear-resistant frame-interlocking composite material scraper as described in claim 1, characterized in that, The composite material used in the injection molding layer comprises a composite material of discontinuous fibers and a resin matrix.

5. The high-strength wear-resistant frame-interlocking composite material scraper as described in claim 4, characterized in that, The composite material used in the injection molding layer also includes one or more combinations of wear-resistant additives, flame retardants, anti-aging agents, and compatibilizers.

6. A high-strength wear-resistant frame-interlocking composite material scraper as described in any one of claims 1-5, characterized in that, The main body section has several positioning screw holes on both sides corresponding to the slot.

7. A method for preparing a high-strength wear-resistant frame-interlocking composite material scraper as described in claim 6, characterized in that, Includes the following steps: S1. The cavities of the alloy steel scraper frame are roughened by sandblasting and coated with a base adhesive layer. S2. Place the alloy steel scraper frame that has completed step S1 into a preheating furnace for preheating treatment to eliminate the cold mold effect. S3. Place the preheated alloy steel scraper frame into the lower mold and perform composite material injection molding; S4. Pressure holding and cooling: The composite material injection layer is cooled and formed in the cavity of the alloy steel scraper frame. After the buck teeth are cooled, the mold opening and demolding operations are carried out.

8. The method for preparing a high-strength wear-resistant frame-interlocking composite material scraper as described in claim 7, characterized in that, In step S2, to eliminate the cold mold effect, the temperature in the preheating furnace is heated to not less than 120°C and held at that temperature for at least 2 hours.

9. The method for preparing a high-strength wear-resistant frame-interlocking composite material scraper as described in claim 7, characterized in that, In step S3, during composite material injection molding, the composite material is heated to a molten flow state of 150°C-170°C before the injection molding operation.

10. The method for preparing a high-strength, wear-resistant frame-interlocking composite material scraper as described in claim 7, characterized in that, During the pressure holding and cooling phase in S4, the pressure holding time is not less than 300s.

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