Super-wear-resistant high-strength conveying belt

Abstract

The invention discloses a super-wear-resistant high-strength conveying belt which comprises covering rubber, the covering rubber comprises cis-butadiene rubber and natural rubber, and the weight ratio of the cis-butadiene rubber to the natural rubber is (60-90): (30-50); a sulfur vulcanization system is adopted, an accelerant NS, an accelerant DM, an accelerant D, sulfur and carbon black N220 or N234 are selected as accelerators, and the weight ratio of the accelerant NS to the accelerant DM to the accelerant D to the sulfur to the carbon black N220 or N234 is (0.5-2): (0.1-0.3): (0.1-0.3): (1-3): (40-60); a double-screw extruder and a calender are adopted for one-time forming process production. The finished product conveying belt prepared by the invention has super-strong tensile strength and abrasion performance, and compared with abrasion loss and stroke tests of a third-party laboratory, the abrasion stroke of the finished product conveying belt is 5-6 times that of an original abrasion-resistant D-grade formula, and the service life of the finished product conveying belt is prolonged by one time or even longer on the basis of the original abrasion-resistant D-grade product.

Description

Technical Field

[0001] The invention relates to a manufacturing technology of a super wear-resistant high-strength conveyor belt, and mainly relates to a super wear-resistant high-strength conveyor belt. Background Art

[0002] Some industries such as coal, mining, ports, chemicals, and metallurgy need to transport materials with uneven particle sizes, hard texture, and irregular edges, which have high requirements for the wear of the working surface of the conveyor belt; at the same time, the material will have a certain impact on the conveyor belt when unloading, and a conveyor belt with higher tensile strength is required to meet the transportation operation. High-strength, wear-resistant conveyor belt materials will become the development trend of the market. With the improvement of material quality requirements, higher requirements are placed on the wear resistance and service life of the conveyor belt. The wear of the existing wear-resistant D-grade products in the GB / T 7984-2013 standard is ≤100mm 3 , tensile strength ≥18MPa, this value is far from enough for some mining users.

[0003] In order to meet the new market demand, some conveyor belt manufacturers have also carried out research on improving the wear performance of conveyor belts. However, the raw materials used involve some special materials, some of which need to be prepared or processed in advance using special processes. Conventional raw materials for non-conveyor belt production are not only expensive, but also limited by order scheduling. Raw materials may be stored for too long, affecting the performance of finished belts. In addition, the preparation of rubber compounds also uses some special processes, which are difficult to expand production due to high cost investment and difficulty in implementation, so it is impossible to achieve large-scale production of finished conveyor belts.

[0004] Therefore, how to produce conveyor belt products with stable performance and significantly extended service life on a large scale, at low cost and with high efficiency is one of the research and development focuses of conveyor belt manufacturers. Summary of the invention

[0005] The object of the present invention is to provide a super wear-resistant and high-strength conveyor belt.

[0006] The purpose of the present invention can be achieved through the following technical solutions:

[0007] A super wear-resistant high-strength conveyor belt comprises a covering rubber, wherein the covering rubber comprises butadiene rubber and natural rubber, and the weight ratio of butadiene rubber to natural rubber is (60-90): (30-50).

[0008] Preferably, a sulfur vulcanization system is adopted, and the accelerator is selected from accelerator NS, accelerator DM, accelerator D, sulfur, carbon black N220 or N234, and the weight ratio thereof is (0.5-2): (0.1-0.3): (0.1-0.3): (1-3): (40-60).

[0009] Furthermore, a twin-screw extruder and a calender are used for one-step molding production.

[0010] Preferably, it also includes antioxidant 4010NA, antioxidant RD, anti-scorch agent CTP, aromatic oil, stearic acid and zinc oxide, and the weight ratio thereof is: (0.5-1.5): (0.5-1.5): (0.2-0.6): (5-7): (2-4): (3-5).

[0011] Furthermore, the preparation method of the covering rubber adopts a two-stage mixing process, firstly mixing the masterbatch on an internal mixer, and then adding the vulcanizing agent and the accelerator for mixing after tableting, cooling and parking.

[0012] Furthermore, the first-stage rubber is mixed using an internal mixer, and the working conditions of the internal mixer are 40rpm, 0.6MPa, natural rubber and butadiene rubber are added for mixing (30-50)s, zinc oxide, stearic acid, antioxidant 4010NA, antioxidant RD and carbon black N220 are added and mixed for (30-50)s, and then aromatic oil is added and mixed for (20-40)s, the temperature is controlled within 125°C and the bolt is raised within (10-30)s, the rubber is discharged to the open mill and continued to be turned over 2-4 times, the roller temperature of the open mill is controlled at (50-70)°C, and finally the second-stage rubber is mixed after cooling, unloading and parking.

[0013] Preferably, during the mixing of the second-stage rubber, the working conditions of the internal mixer are 20 rpm and 0.6 MPa. After the masterbatch is added for mixing for (30-50) s, accelerator NS, accelerator DM, accelerator D, sulfur, and anti-scorch agent CTP are added and mixing is continued for (10-30) s. The temperature is controlled within (80-90) ° C and the plug is raised within (10-20) s. The rubber is discharged to the open mill and the mixing is continued for (2-3) times before cooling and unloading.

[0014] Furthermore, the natural rubber needs to be dried at 45° C. for 20 hours in winter.

[0015] Beneficial technical effects:

[0016] The present invention adopts conventional raw materials through the design of super wear-resistant and high-strength formula. The raw materials do not need to be prepared or processed in advance. The optimization of the formula is completed only by adjusting the types and ratios of the raw materials. The raw materials are easy to obtain. In daily factory-scale production, the production efficiency and the stability of the compound rubber performance will not be affected by the cumbersome raw material processing process. The compound rubber production process conditions are simple and convenient, and factory batch production can be realized without increasing the manufacturing cost of the original wear-resistant D-grade products. The production of finished conveyor belts adopts a one-time molding process of a calender, which improves the production efficiency of the conveyor belts and ensures the quality stability of large-scale production of conveyor belts. The finished conveyor belts prepared by the present invention can achieve a tensile strength of ≥20MPa and a wear loss of ≤20mm. 3After a comparison of wear and stroke tests in a third-party laboratory, the wear stroke is 5 to 6 times that of the original wear-resistant D-grade formula, and the service life of the finished belt is increased by 1 time or even longer than that of the original wear-resistant D-grade product. DETAILED DESCRIPTION

[0017] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0018] A super wear-resistant and high-strength conveyor belt comprises a covering rubber, wherein the covering rubber comprises butadiene rubber and natural rubber, and the weight ratio of butadiene rubber to natural rubber is (60-90): (30-50).

[0019] The invention selects low-priced butadiene rubber with good wear resistance as the main rubber type, and uses natural rubber and butadiene rubber to blend, so as to improve the disadvantage of low anti-blocking ability of butadiene rubber.

[0020] Adopt sulfur vulcanization system, select sulfonamide accelerator NS as main accelerator, and use thiazole accelerator DM to realize synchronous crosslinking of butadiene rubber and natural rubber. In order to improve the tensile strength of covering rubber, guanidine accelerator D is used at the same time, on the basis of improving the physical and mechanical properties of vulcanized rubber, the problem of poor vulcanization flatness is improved. In addition, the smaller the particle size of carbon black, the better the reinforcing effect on rubber, the higher the wear resistance of rubber, and the higher the wear resistance of rubber, the formula design of this patent is completed by selecting N220 or N234 with higher wear resistance. Thus, the present invention selects accelerator NS 0.5-2 weight parts, accelerator DM 0.1-0.3 weight parts, accelerator D 0.1-0.3 weight parts, sulfur 1-3 weight parts, carbon black N220 or N23440-60 weight parts.

[0021] In order to achieve abrasion ≤ 20mm 3 , tensile strength ≥ 20MPa. The raw materials used are commonly available raw materials, no need for advance preparation or treatment, and can be produced on a factory scale. At the same time, the cost of the cover rubber formula will not increase compared to the original wear-resistant D-grade formula.

[0022] The covering rubber of the super wear-resistant and high-strength conveyor belt is a mixed rubber. The production process of the mixed rubber is a conventional process, and there is no need to add special process equipment and processes. The mixed rubber has excellent reprocessability in factory-scale production.

[0023] The present invention adopts a twin-screw extruder and a calendering machine to form a one-step forming process to produce a super wear-resistant and high-strength conveyor belt product, which optimizes the production process of the conveyor belt, not only realizes the integrated large-scale production of calendering and forming, but also saves the time cost and labor cost of the forming process.

[0024] The wear range of super wear-resistant and high-strength conveyor belt products can reach 5 to 6 times that of ordinary wear-resistant conveyor belts. The service life of the conveyor belt is extended by 1 times or even longer, saving users the cost of replacing the conveyor belt.

[0025] A super wear-resistant and high-strength conveyor belt can significantly improve the wear and tensile strength performance of the conveyor belt without increasing production costs, thereby extending the service life of the conveyor belt.

[0026] As for the selection of other additives, 0.5-1.5 parts by weight of commonly available antioxidant 4010NA, 0.5-1.5 parts by weight of antioxidant RD, 0.2-0.6 parts by weight of anti-scorch agent CTP, 5-7 parts by weight of aromatic oil, 2-4 parts by weight of stearic acid, and 3-5 parts by weight of zinc oxide are used.

[0027] The super wear-resistant rubber compound adopts the conventional two-stage mixing process. The masterbatch is first mixed on an internal mixer, and then the vulcanizer and accelerator are added for mixing after tableting, cooling and parking, so that various additives can be effectively dispersed, the viscosity of the rubber is increased, and the reprocessing performance of the compound is improved.

[0028] The present invention uses a twin-screw extruder and a calender to produce a super wear-resistant high-strength conveyor belt in a one-step molding process, omitting the entire molding process, simplifying the conveyor belt production process, improving production efficiency to a certain extent, saving production costs, and realizing high-speed, automated, and large-scale production of super wear-resistant high-strength conveyor belts. The present invention realizes the full-process large-scale production of mixed rubber-finished belts of super wear-resistant high-strength conveyor belts, and the production process is simple and controllable, and the manufacturing cost is low.

[0029] 1. Production of ultra-wear-resistant and high-strength conveyor belts

[0030] Comparative Example 1

[0031] 1. Formulation design

[0032] 50 parts by weight of butadiene rubber, 50 parts by weight of natural rubber, 10 parts by weight of reclaimed rubber, 1 part by weight of accelerator DTDM, 1 part by weight of accelerator CZ, 1 part by weight of sulfur, 5 parts by weight of carbon black N22055, 1 part by weight of antioxidant 4010NA, 1.5 parts by weight of antioxidant RD, 2.5 parts by weight of protective wax, 10 parts by weight of aromatic oil, 2 parts by weight of stearic acid, 4 parts by weight of C5 resin, and 5 parts by weight of zinc oxide.

[0033] 2. Determination of rubber mixing process

[0034] When mixing the rubber masterbatch, the working conditions of the internal mixer are 40rpm and 0.6MPa. The plasticized natural rubber (the rubber needs to be dried in winter: 45℃×20h) and butadiene rubber are added and mixed for 40s. Zinc oxide, stearic acid, antioxidant 4010NA, antioxidant RD and carbon black N220 are added and mixed for 40s. Then aromatic oil is added and mixed for 30s. The temperature is controlled within 125℃ and the plug is raised within 20s. The rubber is discharged to the open mill and continued to be turned over for 3 times. The roller temperature of the open mill is controlled at 60℃. Finally, the second stage rubber mixing is carried out after cooling, unloading and parking. When mixing the second stage rubber, the working conditions of the internal mixer are 20rpm and 0.6MPa. After mixing the masterbatch for 40s, add accelerator NS, accelerator DM, accelerator D, sulfur, and anti-scorch agent CTP and continue mixing for 20s. The temperature is controlled within 85℃ and the bolt is raised within 15s. The rubber is discharged to the open mixer and continues to be turned over for 2 times before cooling and unloading. The mixed rubber can be used after being parked for 8h.

[0035] 3. Finished belt production

[0036] The super wear-resistant high-strength rubber compound is placed in a twin-screw extruder, and a super wear-resistant high-strength conveyor belt blank is produced through a one-step molding process of a calender. The super wear-resistant high-strength conveyor belt blank is vulcanized at a vulcanization temperature of 147°C, and the vulcanization time is calculated according to the conveyor belt model.

[0037] Example 1

[0038] 1. Formulation design

[0039] The super wear-resistant and high-strength formula selects the following raw materials and proportions: 67 parts by weight of butadiene rubber, 33 parts by weight of natural rubber, 0.9 parts by weight of accelerator NS, 0.15 parts by weight of accelerator DM, 0.25 parts by weight of accelerator D, 1.5 parts by weight of sulfur, 57 parts by weight of carbon black N220, 1 part by weight of antioxidant 4010NA, 1 part by weight of antioxidant RD, 0.2 parts by weight of anti-scorch agent CTP, 5.5 parts by weight of aromatic oil, 2.5 parts by weight of stearic acid, and 4 parts by weight of zinc oxide.

[0040] 2. Determination of rubber mixing process

[0041] The same rubber mixing production process as that of Comparative Example 1 was adopted. During the rubber masterbatch, the working conditions of the internal mixer were 40 rpm and 0.6 MPa. The plasticized natural rubber (the rubber needs to be dried in winter: 45°C×20h) and butadiene rubber were added and mixed for 40 seconds. Zinc oxide, stearic acid, antioxidant 4010NA, antioxidant RD and carbon black N220 were added and mixed for 40 seconds. Then aromatic oil was added and mixed for 30 seconds. The temperature was controlled within 125°C and the bolt was raised within 20 seconds. The rubber was discharged to the open mill and continued to be turned over 3 times. The roller temperature of the open mill was controlled at 60°C. Finally, the second-stage rubber mixing was carried out after cooling, unloading and parking. When mixing the second stage rubber, the working conditions of the internal mixer are 20rpm and 0.6MPa. After mixing the masterbatch for 40s, add accelerator NS, accelerator DM, accelerator D, sulfur, and anti-scorch agent CTP and continue mixing for 20s. The temperature is controlled within 85℃ and the bolt is raised within 15s. The rubber is discharged to the open mixer and continues to be turned over for 2 times before cooling and unloading. The mixed rubber can be used after being parked for 8h.

[0042] 3. Finished belt production

[0043] The super wear-resistant high-strength rubber compound is placed in a twin-screw extruder, and a super wear-resistant high-strength conveyor belt blank is produced through a one-step molding process of a calender. The super wear-resistant high-strength conveyor belt blank is vulcanized at a vulcanization temperature of 147°C, and the vulcanization time is calculated according to the conveyor belt model.

[0044] Example 2

[0045] 1. Formulation design

[0046] To extend the scorch time of the mixed rubber and make its reprocessing performance more excellent, the super wear-resistant and high-strength formula selects the following raw materials and proportions: 67 parts by weight of butadiene rubber, 33 parts by weight of natural rubber, 0.9 parts by weight of accelerator NS, 0.15 parts by weight of accelerator DM, 0.25 parts by weight of accelerator D, 1.5 parts by weight of sulfur, 57 parts by weight of carbon black N220, 1 part by weight of antioxidant 4010NA, 1 part by weight of antioxidant RD, 0.4 parts by weight of anti-scorch agent CTP, 5.5 parts by weight of aromatic oil, 2.5 parts by weight of stearic acid, and 4 parts by weight of zinc oxide.

[0047] 2. Determination of rubber mixing process

[0048] The mixing process conditions in Example 1 were adjusted as follows: the masterbatch plug temperature was adjusted to less than 130°C, the roll temperature of the mixing mill was adjusted to 85°C, and the speed of the internal mixer was adjusted to 25 rpm during the second-stage mixing. The other process conditions remained unchanged, and the mixed rubber was used to produce a finished product of an ultra-wear-resistant and high-strength conveyor belt.

[0049] 3. Finished belt production

[0050] The super wear-resistant high-strength rubber compound is placed in a twin-screw extruder, and a super wear-resistant high-strength conveyor belt blank is produced through a one-step molding process of a calender. The super wear-resistant high-strength conveyor belt blank is vulcanized at a vulcanization temperature of 147°C, and the vulcanization time is calculated according to the conveyor belt model.

[0051] Example 3

[0052] 1. Formulation design

[0053] The formula was further adjusted to make its reprocessing performance even better: 57 parts by weight of butadiene rubber, 43 parts by weight of natural rubber, 0.9 parts by weight of accelerator NS, 0.15 parts by weight of accelerator DM, 0.25 parts by weight of accelerator D, 1.5 parts by weight of sulfur, 55 parts by weight of carbon black N23455, 1 part by weight of antioxidant 4010NA, 1 part by weight of antioxidant RD, 0.4 parts by weight of anti-scorch agent CTP, 5.5 parts by weight of aromatic oil, 2.5 parts by weight of stearic acid, and 4 parts by weight of zinc oxide.

[0054] 2. Determination of rubber mixing process

[0055] The mixing process conditions are consistent with those in Example 2. When mixing the rubber masterbatch, the working conditions of the internal mixer are 40rpm and 0.6MPa, and the natural rubber (need to be baked in winter: 45℃×20h) and butadiene rubber after plasticization are added and mixed for 40s, and zinc oxide, stearic acid, antioxidant 4010NA, antioxidant RD and carbon black N220 are added and mixed for 40s, and then aromatic oil is added and mixed for 30s, the temperature is controlled within 130℃ and the bolt is raised within 20s, and the rubber is discharged to the open mill and continued to be turned over 3 times, and the roller temperature of the open mill is controlled at 85℃, and finally cooled, unloaded, and parked for the second stage rubber mixing. When mixing the second stage rubber, the working conditions of the internal mixer are 25rpm and 0.6MPa. After mixing the masterbatch for 40s, add accelerator NS, accelerator DM, accelerator D, sulfur, and anti-scorch agent CTP and continue mixing for 20s. The temperature is controlled within 85℃ and the bolt is raised within 15s. The rubber is discharged to the open mixer and continues to be turned over for 2 times before cooling and unloading. The mixed rubber can be used after being parked for 8h.

[0056] 3. Finished belt production

[0057] The super wear-resistant high-strength rubber compound is placed in a twin-screw extruder, and a super wear-resistant high-strength conveyor belt blank is produced through a one-step molding process of a calender. The super wear-resistant high-strength conveyor belt blank is vulcanized at a vulcanization temperature of 147°C, and the vulcanization time is calculated according to the conveyor belt model.

[0058] 2. Performance Test

[0059] The performance test results are shown in the following table:

[0060] project Tensile strength (MPa) Elongation(%) <![CDATA[Wear amount (mm 3 )]]> Mooney Scorched min Comparative Example 1 18.5 560 66.3 30.23 Example 1 17.1 480 37.7 11.20 Example 2 20.7 640 29.2 36.50 Example 3 22.1 600 15.5 33.27

[0061] The wear of Examples 1, 2, and 3 is significantly lower than that of Comparative Example 1. Through further improvements in the formulation and mixing process, Examples 2 and 3 have achieved the initial design expectations, and the implementation scheme of Example 3 makes the physical properties of the conveyor belt even better, achieving a tensile strength of ≥20MPa and a wear of ≤20mm. 3 At the same time, the reprocessing performance of the compound rubber is stable.

[0062] 2. Test Verification

[0063] 1. Comparison of roller wear stroke test

[0064] The roller wear stroke can simulate the wear of rubber during use to a certain extent. The wear stroke test of the rubber compound of Example 3 and Comparative Example 1 was compared, and the specific data is shown in the table below. Under the same wear amount, the wear stroke of the super wear-resistant rubber compound is 5 to 6 times that of the wear-resistant grade D. Conservative calculation: Under the same working conditions, the service life of the super wear-resistant high-strength conveyor belt is more than 1 times longer than that of the wear-resistant grade D.

[0065]

[0066]

[0067] 2. Comparison of wear test in third-party laboratories

[0068] The wear of the rubber mix in Example 3 was compared with that of an external third-party testing laboratory: Sinochem New Materials Laboratory, and the results were basically consistent. Specific experimental data are shown in the table below.

[0069] laboratory <![CDATA[Wear ① (mm 3 )]]> <![CDATA[Wear ② (mm 3 )]]> <![CDATA[Wear ③ (mm 3 )]]> <![CDATA[Average wear amount (mm 3 )]]> The Company 26.4 30.8 24.2 27.1 Sinochem New Materials Laboratory 31.2 23.7 20.7 25.2

[0070] Through the wear test comparison and wear stroke test comparison conducted by a third-party testing agency, the new product has excellent wear performance, which significantly improves its service life. At the same time, based on user feedback, the actual service life data is obtained: it can be increased by 1 times or even longer based on the original wear-resistant D-level product.

[0071] As mentioned above, the ultra-wear-resistant and high-strength conveyor belts have achieved factory-scale production, while achieving the same cost as the original wear-resistant D-grade products, with excellent performance and greatly improved service life.

[0072] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A super wear-resistant and high-strength conveyor belt, characterized in that: The invention comprises covering rubber, wherein the covering rubber comprises butadiene rubber and natural rubber, and the weight ratio of butadiene rubber to natural rubber is (60-90): (30-50).

2. The ultra-wear-resistant and high-strength conveyor belt according to claim 1, characterized in that: A sulfur vulcanization system is adopted, and the accelerators are selected from accelerator NS, accelerator DM, accelerator D, sulfur, carbon black N220 or N234, and the weight ratio thereof is (0.5-2): (0.1-0.3): (0.1-0.3): (1-3): (40-60).

3. The ultra-wear-resistant and high-strength conveyor belt according to claim 2, characterized in that: It is produced by a one-step molding process using a twin-screw extruder and a calender.

4. The ultra-wear-resistant and high-strength conveyor belt according to claim 2, characterized in that: It also includes antioxidant 4010NA, antioxidant RD, anti-scorch agent CTP, aromatic oil, stearic acid and zinc oxide, and the weight ratio thereof is: (0.5-1.5): (0.5-1.5): (0.2-0.6): (5-7): (2-4): (3-5).

5. The ultra-wear-resistant and high-strength conveyor belt according to claim 4, characterized in that: The preparation method of the covering rubber adopts a two-stage mixing process, firstly mixing the masterbatch on an internal mixer, and then adding a vulcanizing agent and an accelerator for mixing after tableting, cooling and parking.

6. The ultra-wear-resistant and high-strength conveyor belt according to claim 5, characterized in that: The first stage rubber is mixed using an internal mixer, and the working conditions of the internal mixer are 40rpm, 0.6MPa, natural rubber and butadiene rubber are added for mixing (30-50)s, zinc oxide, stearic acid, antioxidant 4010NA, antioxidant RD and carbon black N220 are added and mixed for (30-50)s, and then aromatic oil is added and mixed for (20-40)s. The temperature is controlled within 125℃ and the bolt is raised within (10-30)s. The rubber is discharged to the open mill and continued to be turned over 2-4 times. The roller temperature of the open mill is controlled at (50-70)℃. Finally, the second stage rubber is mixed after cooling, unloading and parking.

7. The ultra-wear-resistant and high-strength conveyor belt according to claim 6, characterized in that: During the mixing of the second-stage rubber, the working conditions of the internal mixer are 20rpm and 0.6MPa. After the masterbatch is added for mixing for (30-50)s, accelerator NS, accelerator DM, accelerator D, sulfur and anti-scorch agent CTP are added and mixing is continued for (10-30)s. The temperature is controlled within (80-90)℃ and the plug is raised within (10-20)s. The rubber is discharged to the open mill and continued to be turned over (2-3 times) before cooling and unloading.

8. The ultra-wear-resistant and high-strength conveyor belt according to claim 6, characterized in that: The natural rubber needs to be dried at 45°C for 20 hours in winter.

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