Preparation process of impact-resistant flame-retardant conveying belt

Abstract

The application provides a preparation process of an impact-resistant and flame-retardant conveying belt, and relates to the technical field of conveying belt manufacturing.The process comprises the following steps: S1, preparation of modified base glue; S2, preparation of a double-layer composite layer, including a reinforcing layer and an elastic buffer layer; S3, treatment of a belt core, wherein polyester canvas is immersed in a bonding agent solution for impregnation, the temperature is adjusted to 65-75 DEG C, and the time is 3-6 min, so that modified polyester canvas is obtained; S4, forming of a blank, wherein the following layers are sequentially laid on a forming machine workbench: a lower layer of flame-retardant base glue, modified polyester canvas, an elastic buffer layer, an aramid fiber net, and an upper layer of flame-retardant base glue, so that a blank is obtained; S5, segmented vulcanization, wherein the pre-pressed blank is placed in a vulcanization tank for segmented vulcanization; and S6, performance detection.The conveying belt prepared by the application is made of a composite flame retardant and an impact-resistant material, the flame retardance and impact resistance of the conveying belt are improved, the safety hidden danger caused by fire or mechanical impact during use is effectively reduced, and the safety of operation is ensured.

Description

Technical Field

[0001] This invention relates to the field of conveyor belt manufacturing technology, and in particular to a process for preparing an impact-resistant and flame-retardant conveyor belt. Background Technology

[0002] With the acceleration of industrialization, conveyor belts, as an indispensable and important component of modern production, are widely used in many fields such as mining, chemical industry, metallurgy, and agriculture. As the scale of industrial production continues to expand and the production environment becomes increasingly complex, the performance requirements for conveyor belts are also getting higher and higher.

[0003] Traditional conveyor belts are mostly made of ordinary rubber materials, which lack effective flame retardant properties and are prone to causing fires in high-temperature and flammable environments, posing safety hazards to equipment and personnel. In addition, traditional conveyor belts do not perform well in terms of wear resistance and tear resistance, which leads to wear and tear during long-term use, increasing the maintenance costs and replacement frequency of enterprises and reducing production efficiency. Summary of the Invention

[0004] The purpose of this invention is to provide a manufacturing process for an impact-resistant and flame-retardant conveyor belt, thereby solving the technical problems existing in the prior art.

[0005] To achieve the above-mentioned objectives, the technical solution adopted by this invention is as follows:

[0006] A process for preparing an impact-resistant and flame-retardant conveyor belt includes the following steps: S1: Preparation of modified base rubber: Natural rubber, nitrile rubber, nano-calcium carbonate, composite flame retardant, antioxidant, sulfur, accelerator, and softener are taken in a preset proportion; Natural rubber and nitrile rubber are put into a mixer and mixed to obtain a reinforcing colloid; then, the composite flame retardant, antioxidant, sulfur, accelerator, and softener are added to it, and it is mixed again to obtain a flame-retardant base rubber; S2: Preparation of a double-layer composite layer, including a reinforcing layer and an elastic buffer layer; The reinforcing layer is an aramid fiber web treated with plasma; The elastic buffer layer is prepared by weighing styrene-butadiene rubber, butyl rubber, nano-silica, and polyisobutylene in a preset proportion, mixing them in a two-roll mill at a temperature of 80-95℃ for 15-20 minutes, and then calendering them into an elastic sheet with a thickness of 1.5-2.55 mm; S3: Belt core treatment: Polyester canvas is immersed in an adhesive solution at a temperature of 65-75℃ for 3-6 minutes; then, it is dried at a temperature of 130-135℃ for 25-30 minutes to obtain modified polyester canvas; S4: Blank forming, a lower layer of flame-retardant base adhesive, modified polyester canvas, elastic buffer layer, aramid fiber web, and an upper layer of flame-retardant base adhesive are sequentially laid on the worktable of the forming machine to obtain a blank; the blank is pre-compressed at a pressure of 20-25MPa and a temperature of 130-140℃ using the forming machine, and the temperature and pressure are maintained for 15-25 minutes to remove interlayer air and make the interlayer adhesion ≥95%; S5: Segmented vulcanization, the pre-compressed blank is placed in a vulcanization tank for segmented vulcanization, and then the vulcanized blank is naturally cooled to room temperature to obtain an impact-resistant and flame-retardant conveyor belt; S6: Performance testing, the impact-resistant and flame-retardant conveyor belt is subjected to performance testing.

[0007] Furthermore, the composite flame retardant is composed of ammonium polyphosphate, melamine cyanurate, and organically modified montmorillonite in a mass ratio of 4:2:1; the antioxidant is... -Isopropyl- -Phenylacetic diamine; the accelerator is tetramethylthiuram disulfide; the softener is dioctyl phthalate.

[0008] Further, step S3 includes: S3.1: Phenolic resin and nitrile rubber latex are mixed in an ethanol solution at a mass ratio of 1:2.5 and stirred to form an adhesive solution; S3.2: Polyester canvas is placed in an impregnation tank and completely immersed in the adhesive solution. The temperature is adjusted to 65-75℃ and the impregnation time is 3-6 minutes. The solution can be stirred during the impregnation process; S3.3: The polyester canvas is removed from the impregnation tank and hung on a draining rack. The draining time is controlled at 30-40 minutes; S3.4: The drained polyester canvas is placed in a drying device, the temperature is adjusted to 130-135℃, and the drying time is 25-30 minutes to form modified polyester canvas.

[0009] Furthermore, in step S4, the thickness of the lower flame-retardant base adhesive is 4-5 mm; the modified polyester canvas consists of 1-3 layers; and the thickness of the upper flame-retardant base adhesive is 6-7 mm.

[0010] Furthermore, the segmented vulcanization in step S5 includes: S5.1: First stage vulcanization: the pre-compressed preform is placed in a vulcanization tank, and the temperature is adjusted to 145-155℃, the pressure to 18-25MPa, and the time to 25-30min; S5.2: Second stage vulcanization: the temperature is adjusted to 160-180℃, the pressure is maintained at 18-25MPa, and the time to 30-35min; S5.3: Third stage vulcanization: under the condition of maintaining a pressure of 18-25MPa, the temperature is programmed to drop to below 100℃ at a rate of 1-2℃ / min.

[0011] Furthermore, the performance testing in step S6 includes: conveyor belt oxygen index, interlayer peel strength, vertical burning rating, drop hammer impact crushing area, wear resistance test, and antistatic performance test.

[0012] Compared with the prior art, the present invention has the following beneficial effects:

[0013] (i) The conveyor belt made by the present invention is made of composite flame retardant and impact-resistant material, which improves the flame retardancy and impact resistance of the conveyor belt, effectively reduces the safety hazards caused by fire or mechanical impact during use, and ensures the safety of operation; and the combination of modified polyester canvas and double-layer composite material structure in the present invention gives the conveyor belt good wear resistance and tear resistance, extends its service life, reduces the replacement frequency, and reduces enterprise costs.

[0014] (ii) The conveyor belt of the present invention has the characteristics of impact resistance and flame retardancy, and can also adapt to different industrial environments, thus improving the versatility of the product. Attached Figure Description

[0015] Figure 1 This is a flowchart of the present invention. Detailed Implementation

[0016] To make the content of this invention easier to understand, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Identical components are represented by the same reference numerals. It should be noted that the terms "front," "rear," "left," "right," "up," and "down" used in the following description refer to directions in the accompanying drawings, while the terms "inner" and "outer" refer to directions toward or away from the geometric center of a specific component, respectively.

[0017] Example 1:

[0018] like Figure 1 As shown, this embodiment provides a manufacturing process for an impact-resistant and flame-retardant conveyor belt, including the following steps:

[0019] Raw material proportions: 50 parts natural rubber, 20 parts nitrile rubber, 4 parts nano calcium carbonate, 15 parts composite flame retardant, 1 part antioxidant, 0.5 parts sulfur, 0.8 parts accelerator, 3 parts softener; 70 parts styrene-butadiene rubber, 40 parts butyl rubber, 5 parts nano silica, 2 parts polyisobutylene.

[0020] Preparation process:

[0021] S1: Preparation of modified base rubber: Natural rubber, nitrile rubber, nano-calcium carbonate, composite flame retardant, antioxidant, sulfur, accelerator, and softener are taken in predetermined proportions. The natural rubber possesses elasticity and processability; the nitrile rubber possesses oil resistance, abrasion resistance, and anti-aging properties; the composite flame retardant improves the overall thermal stability and barrier properties of the material, further enhancing the flame retardant effect; the antioxidant effectively delays the aging process of the rubber; the accelerator improves the strength, hardness, abrasion resistance, and other physical and mechanical properties of the rubber, while also significantly shortening the sulfurization process. The process reduces downtime and improves production efficiency. The softener has a good plasticizing effect and can effectively reduce the interaction force between rubber molecules. Natural rubber and nitrile rubber are put into a mixer and mixed at a temperature of 70°C, a speed of 50 r / min, and a time of 5 min to obtain a reinforced colloid. Then, a composite flame retardant, antioxidant, sulfur, accelerator, and softener are added to it, and the mixing temperature is adjusted to 100°C, a speed of 30 r / min, and a time of 8 min. The Mooney viscosity of the mixed rubber is controlled to be 60 MU to obtain a flame-retardant base rubber.

[0022] S2: Preparation of a double-layer composite layer, including a reinforcing layer and an elastic buffer layer; the reinforcing layer is an aramid fiber web treated with plasma. The aramid fiber web has the characteristics of high strength, high modulus, and low density, which can improve the structural strength and stability of the conveyor belt. Through plasma-induced physical and chemical changes, the surface roughness of the fiber increases and the number of active groups increases, thereby improving the tensile strength and tear resistance of the conveyor belt, enabling it to cope with complex working conditions; the preparation process of the elastic buffer layer involves weighing styrene-butadiene rubber, butyl rubber, nano silica, and polyisobutylene according to a preset ratio, and mixing them in an open mill at a temperature of 80°C for 15 minutes. The rollers of the open mill continuously apply shear force and friction to the materials, so that the various materials are fully mixed and uniform, and the molecules penetrate and entangle with each other to form a uniform and stable system; then, it is calendered into an elastic sheet with a thickness of 1.5 mm, which can effectively absorb and buffer external impact forces, protect other structural layers of the conveyor belt from damage, improve the impact resistance of the conveyor belt, and ensure that it can still operate normally when facing various impact loads;

[0023] S3: Core treatment involves immersing the polyester canvas in an adhesive solution at 65°C for 3 minutes; then drying it at 130°C for 25 minutes to obtain the modified polyester canvas; specifically including:

[0024] S3.1: Phenolic resin and nitrile rubber latex are mixed in an ethanol solution at a mass ratio of 1:2.5 and stirred to form an adhesive solution;

[0025] S3.2: Place the polyester canvas in the impregnation tank and completely immerse it in the adhesive solution to allow it to fully absorb the effective components in the adhesive solution; adjust the temperature to 65℃ to achieve a more ideal molecular activity of the adhesive solution, which is conducive to the better penetration of phenolic resin and nitrile rubber latex into the fiber structure of the polyester canvas; the impregnation time is 3 minutes, and the solution can be stirred during the impregnation process to allow the polyester canvas and the adhesive solution to undergo physical and chemical adsorption, thereby making the two tightly bonded;

[0026] S3.3: Remove the polyester canvas from the impregnation tank and hang it on the draining rack. The draining time should be controlled within 30 minutes.

[0027] S3.4: Place the drained polyester canvas into a drying equipment, adjust its temperature to 130℃, and dry it for 25 minutes to form a modified polyester canvas, which provides a more reliable structural support for the conveyor belt, ensuring that the layers of the conveyor belt can fit tightly together during long-term use and jointly withstand various external forces, thereby improving the overall performance and service life of the conveyor belt.

[0028] S4: Preform Forming. On the molding machine's worktable, a lower layer of flame-retardant base adhesive, modified polyester canvas, an elastic cushioning layer, an aramid fiber mesh, and an upper layer of flame-retardant base adhesive are sequentially laid to obtain the preform. The molding machine is used to apply a pressure of 20 MPa and a temperature of 130°C to the preform for pre-pressing, maintaining the temperature and pressure for 15 minutes to expel interlayer air and ensure interlayer adhesion ≥95%. The lower layer of flame-retardant base adhesive has a thickness of 4 mm; the modified polyester canvas consists of 1-3 layers; and the upper layer of flame-retardant base adhesive has a thickness of 6 mm.

[0029] S5: Segmented vulcanization, the pre-compressed preform is placed in a vulcanization tank for vulcanization in stages, and then the vulcanized preform is naturally cooled to room temperature to obtain an impact-resistant and flame-retardant conveyor belt.

[0030] The segmented vulcanization includes:

[0031] S5.1: First stage vulcanization: The pre-compressed preform is placed in a vulcanization tank, and the temperature is adjusted to 145℃, the pressure to 18MPa, and the time to 25min, so that the adhesive layer is initially cross-linked.

[0032] S5.2: Second stage vulcanization: Adjust the temperature to 160℃, maintain the pressure at 18MPa, and the time is 30min to achieve deep cross-linking of the adhesive layer. At this time, the degree of vulcanization is 78%-85%.

[0033] S5.3: Third stage vulcanization: Under the condition of maintaining a pressure of 18MPa, the temperature is programmed to drop to below 100℃ at a rate of 1-2℃ / min, so that the rubber molecules have enough time to self-adjust and adapt in the gradually decreasing temperature environment, further optimizing the cross-linking structure and eliminating internal stress.

[0034] S6: Performance testing, including performance testing of the impact-resistant and flame-retardant conveyor belt; including: conveyor belt oxygen index, interlayer peel strength, vertical flammability rating, drop hammer impact crushing area, abrasion resistance test, and antistatic performance test; the conveyor belt oxygen index is used to measure the ease of combustion of the material; the interlayer peel strength is used to evaluate the bonding strength between the layers; the vertical flammability rating is used to evaluate the flame-retardant ability of the conveyor belt when placed vertically; the drop hammer impact crushing area is used to measure whether the conveyor belt can be used normally under harsh working conditions; the conveyor belt oxygen index, interlayer peel strength, vertical flammability rating, drop hammer impact crushing area, abrasion resistance test, and antistatic performance test are all existing technologies and will not be discussed in detail here.

[0035] Example 2:

[0036] This embodiment provides a process for manufacturing an impact-resistant and flame-retardant conveyor belt, including the following steps:

[0037] Raw material proportions: 80 parts natural rubber, 25 parts nitrile rubber, 10 parts nano calcium carbonate, 25 parts composite flame retardant, 3 parts antioxidant, 1 part sulfur, 1.6 parts accelerator, 9 parts softener; 80 parts styrene-butadiene rubber, 45 parts butyl rubber, 15 parts nano silica, 3 parts polyisobutylene.

[0038] Preparation process:

[0039] S1: Preparation of modified base rubber: Natural rubber, nitrile rubber, nano-calcium carbonate, composite flame retardant, antioxidant, sulfur, accelerator, and softener are taken in predetermined proportions; the natural rubber has elasticity and processability; the nitrile rubber has oil resistance, abrasion resistance, and anti-aging properties; the composite flame retardant is composed of ammonium polyphosphate, melamine cyanurate, and organic modified montmorillonite in a mass ratio of 4:2:1, which can improve the overall thermal stability and barrier properties of the material and further enhance the flame retardant effect; the antioxidant is... -Isopropyl- -Phenylenediamine can effectively delay the aging process of rubber; the accelerator is tetramethylthiuram disulfide, which can improve the physical and mechanical properties of rubber such as strength, hardness, and abrasion resistance, while also greatly shortening the vulcanization time and improving production efficiency; the softener is dioctyl phthalate, which has good plasticizing effect and can effectively reduce the interaction force between rubber molecules; natural rubber and nitrile rubber are put into a mixer and mixed at a temperature of 80°C, a speed of 70 r / min, and a time of 10 min to obtain a reinforced colloid. Then, a composite flame retardant, antioxidant, sulfur, accelerator, and softener are added to it, and the mixing temperature is adjusted to 120°C, a speed of 35 r / min, and a time of 13 min, while controlling the Mooney viscosity of the mixed rubber to 90 MU to obtain a flame-retardant base rubber;

[0040] S2: Preparation of a double-layer composite layer, including a reinforcing layer and an elastic buffer layer; the reinforcing layer is an aramid fiber web treated with plasma. The aramid fiber web has the characteristics of high strength, high modulus, and low density, which can improve the structural strength and stability of the conveyor belt. Through plasma-induced physical and chemical changes, the surface roughness of the fiber increases and the number of active groups increases, thereby improving the tensile strength and tear resistance of the conveyor belt, enabling it to cope with complex working conditions; the preparation process of the elastic buffer layer involves weighing styrene-butadiene rubber, butyl rubber, nano-silica, and polyisobutylene according to a preset ratio, and mixing them in a two-roll mill at a temperature of 95°C for 20 minutes. The rollers of the two-roll mill continuously apply shear force and friction to the materials, so that the various materials are fully mixed and uniform, and the molecules penetrate and entangle with each other to form a uniform and stable system; then, it is calendered into an elastic sheet with a thickness of 2.55 mm, which can effectively absorb and buffer external impact forces, protect other structural layers of the conveyor belt from damage, improve the impact resistance of the conveyor belt, and ensure that it can still operate normally when facing various impact loads;

[0041] S3: Core treatment involves immersing the polyester canvas in an adhesive solution at 75°C for 6 minutes; then drying it at 135°C for 30 minutes to obtain the modified polyester canvas; specifically including:

[0042] S3.1: Phenolic resin and nitrile rubber latex are mixed in an ethanol solution at a mass ratio of 1:2.5 and stirred to form an adhesive solution;

[0043] S3.2: Place the polyester canvas in the impregnation tank and completely immerse it in the adhesive solution to allow it to fully absorb the effective components in the adhesive solution; adjust the temperature to 75℃ to achieve a more ideal molecular activity of the adhesive solution, which is conducive to the better penetration of phenolic resin and nitrile rubber latex into the fiber structure of the polyester canvas; the impregnation time is 6 minutes, and the solution can be stirred during the impregnation process to allow the polyester canvas and the adhesive solution to undergo physical and chemical adsorption, thereby making the two tightly bonded;

[0044] S3.3: Remove the polyester canvas from the impregnation tank and hang it on the draining rack. The draining time should be controlled within 40 minutes.

[0045] S3.4: Place the drained polyester canvas into a drying equipment, adjust its temperature to 135℃, and dry it for 30 minutes to form a modified polyester canvas, which provides a more reliable structural support for the conveyor belt, ensuring that the layers of the conveyor belt can fit tightly together during long-term use and jointly withstand various external forces, thereby improving the overall performance and service life of the conveyor belt.

[0046] S4: Preform Forming. On the molding machine's worktable, a lower layer of flame-retardant base adhesive, modified polyester canvas, an elastic cushioning layer, an aramid fiber mesh, and an upper layer of flame-retardant base adhesive are sequentially laid to obtain the preform. The molding machine is used to apply a pressure of 25 MPa and a temperature of 140°C to the preform for pre-pressing, maintaining the temperature and pressure for 25 minutes to expel interlayer air, ensuring an interlayer adhesion ≥95%. The lower layer of flame-retardant base adhesive has a thickness of 5 mm; the modified polyester canvas consists of 1-3 layers; and the upper layer of flame-retardant base adhesive has a thickness of 7 mm.

[0047] S5: Segmented vulcanization, the pre-compressed preform is placed in a vulcanization tank for vulcanization in stages, and then the vulcanized preform is naturally cooled to room temperature to obtain an impact-resistant and flame-retardant conveyor belt.

[0048] The segmented vulcanization includes:

[0049] S5.1: First stage vulcanization: The pre-compressed preform is placed in a vulcanization tank, and the temperature is adjusted to 155℃, the pressure to 25MPa, and the time to 30min, so that the adhesive layer is initially cross-linked.

[0050] S5.2: Second stage vulcanization: Adjust the temperature to 180℃, maintain the pressure at 25MPa, and the time is 35min to achieve deep cross-linking of the adhesive layer. At this time, the degree of vulcanization is 85%.

[0051] S5.3: Third stage vulcanization: Under the condition of maintaining a pressure of 25MPa, the temperature is programmed to drop to below 100℃ at a rate of 1-2℃ / min, so that the rubber molecules have enough time to self-adjust and adapt in the gradually decreasing temperature environment, further optimizing the cross-linking structure and eliminating internal stress.

[0052] S6: Performance testing, including performance testing of the impact-resistant and flame-retardant conveyor belt; including: conveyor belt oxygen index, interlayer peel strength, vertical flammability rating, drop hammer impact crushing area, abrasion resistance test, and antistatic performance test; the conveyor belt oxygen index is used to measure the ease of combustion of the material; the interlayer peel strength is used to evaluate the bonding strength between the layers; the vertical flammability rating is used to evaluate the flame-retardant ability of the conveyor belt when placed vertically; the drop hammer impact crushing area is used to measure whether the conveyor belt can be used normally under harsh working conditions; the conveyor belt oxygen index, interlayer peel strength, vertical flammability rating, drop hammer impact crushing area, abrasion resistance test, and antistatic performance test are all existing technologies and will not be discussed in detail here.

[0053] Example 3:

[0054] This embodiment provides a process for manufacturing an impact-resistant and flame-retardant conveyor belt, including the following steps:

[0055] Raw material proportions: 60 parts natural rubber, 23 parts nitrile rubber, 7 parts nano calcium carbonate, 10 parts composite flame retardant, 2 parts antioxidant, 0.75 parts sulfur, 1.3 parts accelerator, 6 parts softener; 75 parts styrene-butadiene rubber, 42 parts butyl rubber, 10 parts nano silica, 2 parts polyisobutylene.

[0056] Preparation process:

[0057] S1: Preparation of modified base rubber: Natural rubber, nitrile rubber, nano-calcium carbonate, composite flame retardant, antioxidant, sulfur, accelerator, and softener are taken in predetermined proportions; the natural rubber has elasticity and processability; the nitrile rubber has oil resistance, abrasion resistance, and anti-aging properties; the composite flame retardant is composed of ammonium polyphosphate, melamine cyanurate, and organic modified montmorillonite in a mass ratio of 4:2:1, which can improve the overall thermal stability and barrier properties of the material and further enhance the flame retardant effect; the antioxidant is... -Isopropyl- -Phenylenediamine can effectively delay the aging process of rubber; the accelerator is tetramethylthiuram disulfide, which can improve the physical and mechanical properties of rubber such as strength, hardness, and abrasion resistance, while also greatly shortening the vulcanization time and improving production efficiency; the softener is dioctyl phthalate, which has good plasticizing effect and can effectively reduce the interaction force between rubber molecules; natural rubber and nitrile rubber are put into a mixer and mixed at a temperature of 75°C, a speed of 60 r / min, and a time of 8 min to obtain a reinforced colloid. Then, a composite flame retardant, antioxidant, sulfur, accelerator, and softener are added to it, and the mixing temperature is adjusted to 110°C, a speed of 32 r / min, and a time of 10 min, while controlling the Mooney viscosity of the mixed rubber to 70 MU to obtain a flame-retardant base rubber;

[0058] S2: Preparation of a double-layer composite layer, including a reinforcing layer and an elastic buffer layer; the reinforcing layer is an aramid fiber web treated with plasma. The aramid fiber web has the characteristics of high strength, high modulus, and low density, which can improve the structural strength and stability of the conveyor belt. Through plasma-induced physical and chemical changes, the surface roughness of the fiber increases and the number of active groups increases, thereby improving the tensile strength and tear resistance of the conveyor belt, enabling it to cope with complex working conditions; the preparation process of the elastic buffer layer involves weighing styrene-butadiene rubber, butyl rubber, nano silica, and polyisobutylene according to a preset ratio, and mixing them in an open mill at a temperature of 85°C for 17 minutes. The rollers of the open mill continuously apply shear force and friction to the materials, so that the various materials are fully mixed and uniform, and the molecules penetrate and entangle with each other to form a uniform and stable system; then, it is calendered into an elastic sheet with a thickness of 2mm, which can effectively absorb and buffer external impact forces, protect other structural layers of the conveyor belt from damage, improve the impact resistance of the conveyor belt, and ensure that it can still operate normally when facing various impact loads;

[0059] S3: Core treatment involves immersing the polyester canvas in an adhesive solution at 70°C for 5 minutes; then drying it at 132°C for 27 minutes to obtain the modified polyester canvas; specifically including:

[0060] S3.1: Phenolic resin and nitrile rubber latex are mixed in an ethanol solution at a mass ratio of 1:2.5 and stirred to form an adhesive solution;

[0061] S3.2: Place the polyester canvas in the impregnation tank and completely immerse it in the adhesive solution to allow it to fully absorb the effective components in the adhesive solution; adjust the temperature to 70℃ to achieve a more ideal molecular activity of the adhesive solution, which is conducive to the better penetration of phenolic resin and nitrile rubber latex into the fiber structure of the polyester canvas; the impregnation time is 5 minutes, and the solution can be stirred during the impregnation process to allow the polyester canvas and the adhesive solution to undergo physical and chemical adsorption, thereby making the two tightly bonded;

[0062] S3.3: Remove the polyester canvas from the impregnation tank and hang it on the draining rack. The draining time should be controlled within 35 minutes.

[0063] S3.4: Place the drained polyester canvas into a drying equipment, adjust its temperature to 132℃, and dry it for 28 minutes to form a modified polyester canvas, which provides a more reliable structural support for the conveyor belt, ensuring that the layers of the conveyor belt can fit tightly together during long-term use and jointly withstand various external forces, thereby improving the overall performance and service life of the conveyor belt.

[0064] S4: Preform Forming. On the molding machine's worktable, a lower layer of flame-retardant base adhesive, modified polyester canvas, an elastic cushioning layer, an aramid fiber mesh, and an upper layer of flame-retardant base adhesive are sequentially laid to obtain the preform. The molding machine is used to apply a pressure of 23 MPa and a temperature of 135°C to the preform for pre-pressing, maintaining the temperature and pressure for 20 minutes to expel interlayer air, ensuring an interlayer adhesion ≥95%. The lower layer of flame-retardant base adhesive has a thickness of 4 mm; the modified polyester canvas consists of 1-3 layers; and the upper layer of flame-retardant base adhesive has a thickness of 7 mm.

[0065] S5: Segmented vulcanization, the pre-compressed preform is placed in a vulcanization tank for vulcanization in stages, and then the vulcanized preform is naturally cooled to room temperature to obtain an impact-resistant and flame-retardant conveyor belt.

[0066] The segmented vulcanization includes:

[0067] S5.1: First stage vulcanization: The pre-compressed preform is placed in a vulcanization tank, and the temperature is adjusted to 150℃, the pressure to 20MPa, and the time to 27min, so that the adhesive layer is initially cross-linked.

[0068] S5.2: Second stage vulcanization: Adjust the temperature to 170℃, maintain the pressure at 19MPa, and the time is 32min to achieve deep cross-linking of the adhesive layer. At this time, the degree of vulcanization is 85%.

[0069] S5.3: Third stage vulcanization: Under the condition of maintaining a pressure of 22MPa, the temperature is programmed to drop to below 100℃ at a rate of 1-2℃ / min, so that the rubber molecules have enough time to self-adjust and adapt in the gradually decreasing temperature environment, further optimizing the cross-linking structure and eliminating internal stress.

[0070] S6: Performance testing, including performance testing of the impact-resistant and flame-retardant conveyor belt; including: conveyor belt oxygen index, interlayer peel strength, vertical flammability rating, drop hammer impact crushing area, abrasion resistance test, and antistatic performance test; the conveyor belt oxygen index is used to measure the ease of combustion of the material; the interlayer peel strength is used to evaluate the bonding strength between the layers; the vertical flammability rating is used to evaluate the flame-retardant ability of the conveyor belt when placed vertically; the drop hammer impact crushing area is used to measure whether the conveyor belt can be used normally under harsh working conditions; the conveyor belt oxygen index, interlayer peel strength, vertical flammability rating, drop hammer impact crushing area, abrasion resistance test, and antistatic performance test are all existing technologies and will not be discussed in detail here.

[0071] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A manufacturing process for an impact-resistant and flame-retardant conveyor belt, characterized in that: Includes the following steps: S1: Preparation of modified base rubber: Take natural rubber, nitrile rubber, nano calcium carbonate, composite flame retardant, antioxidant, sulfur, accelerator, and softener according to the preset proportions; put natural rubber and nitrile rubber into an internal mixer for mixing to obtain a reinforced colloid; then, add the composite flame retardant, antioxidant, sulfur, accelerator, and softener to it, and mix again to obtain a flame-retardant base rubber; S2: Preparation of a double-layer composite layer, including a reinforcing layer and an elastic buffer layer; the reinforcing layer is an aramid fiber web after plasma treatment; the preparation process of the elastic buffer layer is to weigh styrene-butadiene rubber, butyl rubber, nano silica and polyisobutylene according to a preset ratio, mix them in a two-roll mill at a temperature of 80-95℃ for 15-20 minutes, and then calender them into an elastic sheet with a thickness of 1.5-2.55mm; S3: Core treatment, immerse the polyester canvas in the adhesive solution, adjust the temperature to 65-75℃, time 3-6min; then, dry it at 130-135℃ for 25-30min to obtain the modified polyester canvas. S4: Preform forming. On the worktable of the forming machine, a lower layer of flame-retardant base adhesive, modified polyester canvas, elastic cushioning layer, aramid fiber mesh, and an upper layer of flame-retardant base adhesive are laid in sequence to obtain the preform. The forming machine is used to apply a pressure of 20-25 MPa and a temperature of 130-140℃ to the preform for pre-compression, and the temperature and pressure are maintained for 15-25 minutes to remove interlayer air and make the interlayer adhesion ≥95%. S5: Segmented vulcanization, the pre-compressed preform is placed in a vulcanization tank for vulcanization in stages, and then the vulcanized preform is naturally cooled to room temperature to obtain an impact-resistant and flame-retardant conveyor belt. S6: Performance testing, the impact-resistant and flame-retardant conveyor belt is subjected to performance testing.

2. The manufacturing process of the impact-resistant and flame-retardant conveyor belt according to claim 1, characterized in that: The composite flame retardant is composed of ammonium polyphosphate, melamine cyanurate, and organically modified montmorillonite in a mass ratio of 4:2:1; the antioxidant is... -Isopropyl- -Phenylacetic diamine; the accelerator is tetramethylthiuram disulfide; the softener is dioctyl phthalate.

3. The manufacturing process of the impact-resistant and flame-retardant conveyor belt according to claim 1, characterized in that: Step S3 includes: S3.1: Phenolic resin and nitrile rubber latex are mixed in an ethanol solution at a mass ratio of 1:2.5 and stirred to form an adhesive solution; S3.2: Place the polyester canvas into the impregnation tank and completely immerse the polyester canvas in the adhesive solution. Adjust the temperature to 65-75℃ and the impregnation time to 3-6 minutes. The solution can be stirred during the impregnation process. S3.3: Remove the polyester canvas from the impregnation tank and hang it on the draining rack. The draining time should be controlled at 30-40 minutes. S3.4: Place the drained polyester canvas into a drying equipment, adjust its temperature to 130-135℃, and dry it for 25-30 minutes to form modified polyester canvas.

4. The manufacturing process of the impact-resistant and flame-retardant conveyor belt according to claim 1, characterized in that: The thickness of the lower flame-retardant base adhesive in step S4 is 4-5 mm; the modified polyester canvas consists of 1-3 layers; and the thickness of the upper flame-retardant base adhesive is 6-7 mm.

5. The manufacturing process of the impact-resistant and flame-retardant conveyor belt according to claim 1, characterized in that: The segmented vulcanization in step S5 includes: S5.1: First stage vulcanization: Place the pre-compressed preform into a vulcanization tank, adjust the temperature to 145-155℃, the pressure to 18-25MPa, and the time to 25-30min; S5.2: Second stage vulcanization: Adjust the temperature to 160-180℃, maintain the pressure at 18-25MPa, and the time is 30-35min; S5.3: Third stage vulcanization: Under the condition of maintaining a pressure of 18-25MPa, the temperature is programmed to be reduced to below 100℃ at a rate of 1-2℃ / min.

6. The manufacturing process of the impact-resistant and flame-retardant conveyor belt according to claim 1, characterized in that: The performance tests in step S6 include: conveyor belt oxygen index, interlayer peel strength, vertical burning rating, drop hammer impact crushing area, wear resistance test, and antistatic performance test.

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