A novel solid tire for electric forklift and preparation method thereof

Abstract

The present invention discloses a novel solid tire for electric forklift and a preparation method thereof, wherein the tire comprises a tire liner and a tread rubber, wherein the tire liner comprises natural rubber, hydrogenated nitrile rubber, silicone rubber, shock absorbing material, vulcanized material, palmitic acid, anti-aging agent, graphite, accelerator, and aluminum oxide; and the tread rubber comprises natural rubber, hydrogenated nitrile rubber, silicone rubber, shock absorbing material, vulcanized material, palmitic acid, anti-aging agent, graphite, accelerator, aluminum oxide and noise reduction material. The preparation method thereof is as follows: S1 places each raw material component of the tire liner into an internal mixer to prepare the tire liner; S2 places each raw material component of the tread rubber into an internal mixer to prepare the tread rubber; S3 adheres the tread rubber obtained in step S2 to the tire liner obtained in step S1 coated with glue, and after the adhesion is completed, a novel solid tire for electric forklift is prepared. The thermal conductivity of the tire prepared by the present invention is greatly improved, and the noise is reduced during use, so that its application scenarios are more extensive.

Description

Technical Field

[0001] The invention relates to the technical field of solid tires, and in particular to a novel solid tire for electric forklifts and a preparation method thereof. Background Art

[0002] An electric forklift is an industrial transport vehicle powered by a battery and driven by an electric motor. It is mainly used for cargo loading and unloading, stacking and short-distance transportation in warehouses, workshops, cargo yards and other places. Compared with traditional fuel forklifts, electric forklifts have the following characteristics:

[0003] 1. Environmental protection and energy saving: Electric forklifts do not produce exhaust emissions during operation, have low noise, and meet environmental protection requirements. At the same time, the cost of electricity is lower than the cost of fuel, and long-term use can significantly save energy expenses.

[0004] 2. Easy to operate: Electric forklifts generally use electronic control, which is simpler and more flexible to operate, and can effectively reduce the labor intensity of the driver.

[0005] 3. Low maintenance cost: The mechanical structure of the electric forklift is relatively simple, the parts have less wear and tear, the maintenance cost is low, and there is no need to frequently replace the oil and filter.

[0006] 4. High safety: Equipped with emergency power-off switch, anti-skid braking system and other safety devices to improve operation safety.

[0007] 5. Wide range of applications: Suitable for a variety of indoor environments, especially in places with strict requirements on air quality and noise control, such as warehouses in the food and pharmaceutical industries.

[0008] In order to improve the application scenarios of electric forklifts, higher requirements are placed on the performance of their tires, such as shock absorption performance, noise reduction performance, thermal conductivity, etc.

[0009] CN114316387B discloses a shock-absorbing solid tire for telescopic forklift, the tire includes the following raw materials in weight percentage, natural rubber: 80-100 parts, styrene-butadiene rubber: 60-90 parts, butadiene rubber: 3-5 parts, shock-absorbing material: 5-8 parts, vulcanized material: 0.5-1.4 parts, stearic acid: 0.1-0.5 parts, antioxidant: 0.1-0.4 parts, zinc oxide: 0.5-1 parts, accelerator: 0.2-0.5 parts, graphene: 0.3-1.5 parts, and the present invention also discloses a method for preparing a shock-absorbing solid tire for telescopic forklift. The tire prepared by the present invention has excellent performance, and its tensile strength, resilience, elongation at break, and wear resistance index are all good, which is suitable for industrial promotion and application. However, there is still a large room for improvement in performance. Summary of the invention

[0010] In view of the deficiencies in the prior art, the present invention provides a novel solid tire for electric forklifts and a preparation method thereof.

[0011] In order to achieve the above object, the technical solution adopted by the present invention is:

[0012] A novel solid tire for electric forklift, the tire comprising a tire liner and a tread rubber,

[0013] The tire liner includes the following substances by mass fraction:

[0014] Natural rubber: 80~90 parts

[0015] Hydrogenated nitrile rubber: 5~15 parts

[0016] Silicone rubber: 3~5 parts

[0017] Shock-absorbing material: 2~4 pieces

[0018] Vulcanization material: 0.5~2 parts

[0019] Palmitic acid: 0.1~1 part

[0020] Anti-aging agent: 0.2~0.5 parts

[0021] Graphite: 0.5~1 part

[0022] Accelerator: 0.6~1 part

[0023] Alumina: 0.3~1.5 parts

[0024] The tread rubber includes the following substances by mass fraction:

[0025] Natural rubber: 80~90 parts

[0026] Hydrogenated nitrile rubber: 5~15 parts

[0027] Silicone rubber: 3~5 parts

[0028] Shock-absorbing material: 2~4 pieces

[0029] Vulcanization material: 0.5~2 parts

[0030] Palmitic acid: 0.1~1 part

[0031] Anti-aging agent: 0.2~0.5 parts

[0032] Graphite: 0.5~1 part

[0033] Accelerator: 0.6~1 part

[0034] Alumina: 0.3~1.5 parts

[0035] Noise reduction material: 1~2 pieces.

[0036] Furthermore, the vulcanization material is a mixture of sulfur and tert-butyl hydroperoxide, the mass ratio of sulfur to tert-butyl hydroperoxide is 1:1, and adding tert-butyl hydroperoxide to the vulcanization material has a good vulcanization effect and a fast vulcanization speed.

[0037] Furthermore, the shock-absorbing material is a mixture of EPDM rubber and polyamide thermoplastic elastomer, and the mass ratio of the EPDM rubber to the polyamide thermoplastic elastomer is 2:1.

[0038] Furthermore, the antioxidant is at least one of urotropine, cyclohexylamine or p-fluoroaniline. When the antioxidant is urotropine, due to its unique structure and excellent molecular structure, the tire performance is improved; when the antioxidant is cyclohexylamine, it also plays the role of a vulcanization accelerator, and the synergistic effect is good; when the antioxidant is p-fluoroaniline, fluorine atoms are added to the tire, further improving the corrosion resistance of the tire.

[0039] Furthermore, the noise reduction material is a mixture of chlorobutyl rubber and white carbon black, the mass ratio of chlorobutyl rubber to white carbon black is 1:1, and the synergistic effect of chlorobutyl rubber and white carbon black not only makes the components mixed more evenly to balance the mechanical properties and damping properties of the material, but also has better noise reduction and shock absorption effects.

[0040] Furthermore, the accelerator is N-tert-butyl-2-benzothiazole sulfenamide.

[0041] At the same time, the present invention also provides a method for preparing the above-mentioned novel solid tire for electric forklift, comprising the following steps:

[0042] S1: Put the raw material components of the tire liner into an internal mixer, raise the temperature to 50-75°C, and internally mix for 5-8 minutes, then raise the temperature to 140-160°C, internally mix for 10-15 minutes, and finally inject into the tire liner mold to make the tire liner;

[0043] S2: placing the raw material components of the tread rubber into an internal mixer, raising the temperature to 50-75°C, internal mixing for 10-15 minutes, then raising the temperature to 140-150°C, internal mixing for 8-10 minutes, and finally injecting into a tread rubber mold to make the tread rubber;

[0044] S3: The tread rubber obtained in step S2 is adhered to the tire inner liner coated with glue in step S1. After the adhesion is completed, vulcanization is performed to obtain a new solid tire for electric forklifts.

[0045] Furthermore, the vulcanization process is as follows: the tire prepared in step S3 is placed in a vulcanizer, and then nitrogen at a temperature of 130-150° C. is introduced into the system, and vulcanization is performed for 5-10 minutes. Thereafter, nitrogen at 160-170° C. is introduced into the system, and vulcanization is performed for 10-15 minutes. Finally, nitrogen at room temperature is introduced, and the temperature is gradually lowered until the vulcanization is completed.

[0046] The invention adjusts the proper ratio of the tire liner and the tread rubber, and adds alumina and graphite in a suitable ratio, so that the thermal conductivity of the tire is greatly improved. A mixture of chlorobutyl rubber and white carbon black, which is a noise reduction material, is added to the tread rubber, which is not only conducive to the miscibility of the components, but also reduces the noise during use, so that the application scenarios are more extensive. In the tire vulcanization process, hot nitrogen at different temperatures is used for staged vulcanization, and the vulcanization effect is good. In the cooling process, room temperature nitrogen is used for cooling, and the cooling is more uniform. The prepared tire has excellent heat resistance and small compression permanent deformation. DETAILED DESCRIPTION

[0047] The following is a clear and complete description of the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present invention.

[0048] It should be understood that the specific embodiments described herein are only used to explain the present invention, and are not used to limit the present invention.

[0049] Example 1

[0050] A novel solid tire for electric forklift, the tire comprising a tire liner and a tread rubber,

[0051] The tire liner includes the following substances by mass fraction:

[0052] Natural rubber: 800kg

[0053] Hydrogenated nitrile rubber: 50kg

[0054] Silicone rubber: 30kg

[0055] Shock-absorbing material: 24kg

[0056] Vulcanized material: 5kg

[0057] Palmitic acid: 1kg

[0058] Hexamethylenetetramine: 2kg

[0059] Graphite: 5kg

[0060] N-tert-butyl-2-benzothiazole sulfenamide: 8 kg

[0061] Alumina: 3kg

[0062] The tread rubber includes the following substances by mass fraction:

[0063] Natural rubber: 800kg

[0064] Hydrogenated nitrile rubber: 50kg

[0065] Silicone rubber: 30kg

[0066] Shock-absorbing material: 24kg

[0067] Vulcanized material: 5kg

[0068] Palmitic acid: 1kg

[0069] Hexamethylenetetramine: 2kg

[0070] Graphite: 5kg

[0071] N-tert-butyl-2-benzothiazole sulfenamide: 8 kg

[0072] Alumina: 3kg

[0073] Noise reduction material: 10kg.

[0074] The vulcanizing material is a mixture of 2.5 kg sulfur and 2.5 kg tert-butyl hydroperoxide, the shock absorbing material is a mixture of 16 kg EPDM rubber and 8 kg thermoplastic elastomer, and the noise reduction material is a mixture of 5 kg chlorobutyl rubber and 5 kg white carbon black.

[0075] The method for preparing the novel solid tire for electric forklift comprises the following steps:

[0076] S1: Put the raw material components of the tire liner into an internal mixer, raise the temperature to 50-75°C, and internally mix for 5-8 minutes, then raise the temperature to 140-160°C, internally mix for 10-15 minutes, and finally inject into the tire liner mold to make the tire liner;

[0077] S2: placing the raw material components of the tread rubber into an internal mixer, raising the temperature to 50-75°C, internal mixing for 10-15 minutes, then raising the temperature to 140-150°C, internal mixing for 8-10 minutes, and finally injecting into a tread rubber mold to make the tread rubber;

[0078] S3: The tread rubber obtained in step S2 is adhered to the tire inner liner coated with glue in step S1. After the adhesion is completed, the tire prepared in step S3 is placed in a vulcanizer, and then nitrogen at a temperature of 130-150°C is introduced into the system, and vulcanization is performed for 5-10 minutes. Thereafter, nitrogen at 160-170°C is introduced into the system, and vulcanization is performed for 10-15 minutes. Finally, nitrogen at room temperature is introduced, and the temperature is gradually lowered until vulcanization is completed, thereby obtaining a new solid tire for electric forklifts.

[0079] Example 2

[0080] A novel solid tire for electric forklift, the tire comprising a tire liner and a tread rubber,

[0081] The tire liner includes the following substances by mass fraction:

[0082] Natural rubber: 850kg

[0083] Hydrogenated nitrile rubber: 100kg

[0084] Silicone rubber: 30kg

[0085] Shock-absorbing material: 30kg

[0086] Vulcanized material: 10kg

[0087] Palmitic acid: 5kg

[0088] p-Fluoroaniline: 3kg

[0089] Graphite: 8kg

[0090] N-tert-butyl-2-benzothiazole sulfenamide: 8 kg

[0091] Alumina: 10kg

[0092] The tread rubber includes the following substances by mass fraction:

[0093] Natural rubber: 850kg

[0094] Hydrogenated nitrile rubber: 100kg

[0095] Silicone rubber: 30kg

[0096] Shock-absorbing material: 30kg

[0097] Vulcanized material: 10kg

[0098] Palmitic acid: 5kg

[0099] p-Fluoroaniline: 3kg

[0100] Graphite: 8kg

[0101] N-tert-butyl-2-benzothiazole sulfenamide: 8 kg

[0102] Alumina: 10kg

[0103] Noise reduction material: 15kg.

[0104] The vulcanizing material is a mixture of 5 kg sulfur and 5 kg tert-butyl hydroperoxide, the shock absorbing material is a mixture of 20 kg EPDM rubber and 10 kg thermoplastic elastomer, and the noise reduction material is a mixture of 7.5 kg chlorobutyl rubber and 7.5 kg white carbon black.

[0105] The method for preparing the novel solid tire for electric forklift comprises the following steps:

[0106] S1: Put the raw material components of the tire liner into an internal mixer, raise the temperature to 50-75°C, and internally mix for 5-8 minutes, then raise the temperature to 140-160°C, internally mix for 10-15 minutes, and finally inject into the tire liner mold to make the tire liner;

[0107] S2: placing the raw material components of the tread rubber into an internal mixer, raising the temperature to 50-75°C, internal mixing for 10-15 minutes, then raising the temperature to 140-150°C, internal mixing for 8-10 minutes, and finally injecting into a tread rubber mold to make the tread rubber;

[0108] S3: The tread rubber obtained in step S2 is adhered to the tire inner liner coated with glue in step S1. After the adhesion is completed, the tire prepared in step S3 is placed in a vulcanizer, and then nitrogen at a temperature of 130-150°C is introduced into the system, and vulcanization is performed for 5-10 minutes. Thereafter, nitrogen at 160-170°C is introduced into the system, and vulcanization is performed for 10-15 minutes. Finally, nitrogen at room temperature is introduced, and the temperature is gradually lowered until vulcanization is completed, thereby obtaining a new solid tire for electric forklifts.

[0109] Example 3

[0110] A novel solid tire for electric forklift, the tire comprising a tire liner and a tread rubber,

[0111] The tire liner includes the following substances by mass fraction:

[0112] Natural rubber: 820kg

[0113] Hydrogenated nitrile rubber: 100kg

[0114] Silicone rubber: 30kg

[0115] Shock-absorbing material: 30kg

[0116] Vulcanized material: 10kg

[0117] Palmitic acid: 6kg

[0118] Cyclohexylamine: 3kg

[0119] Graphite: 8kg

[0120] N-tert-butyl-2-benzothiazole sulfenamide: 8 kg

[0121] Alumina: 10kg

[0122] The tread rubber includes the following substances by mass fraction:

[0123] Natural rubber: 820kg

[0124] Hydrogenated nitrile rubber: 100kg

[0125] Silicone rubber: 30kg

[0126] Shock-absorbing material: 30kg

[0127] Vulcanized material: 10kg

[0128] Palmitic acid: 6kg

[0129] Cyclohexylamine: 3kg

[0130] Graphite: 8kg

[0131] N-tert-butyl-2-benzothiazole sulfenamide: 8 kg

[0132] Alumina: 10kg

[0133] Noise reduction material: 15kg.

[0134] The vulcanizing material is a mixture of 5 kg sulfur and 5 kg tert-butyl hydroperoxide, the shock absorbing material is a mixture of 20 kg EPDM rubber and 10 kg thermoplastic elastomer, and the noise reduction material is a mixture of 7.5 kg chlorobutyl rubber and 7.5 kg white carbon black.

[0135] The method for preparing the novel solid tire for electric forklift comprises the following steps:

[0136] S1: Put the raw material components of the tire liner into an internal mixer, raise the temperature to 50-75°C, and internally mix for 5-8 minutes, then raise the temperature to 140-160°C, internally mix for 10-15 minutes, and finally inject into the tire liner mold to make the tire liner;

[0137] S2: placing the raw material components of the tread rubber into an internal mixer, raising the temperature to 50-75°C, internal mixing for 10-15 minutes, then raising the temperature to 140-150°C, internal mixing for 8-10 minutes, and finally injecting into a tread rubber mold to make the tread rubber;

[0138] S3: The tread rubber obtained in step S2 is adhered to the tire inner liner coated with glue in step S1. After the adhesion is completed, the tire prepared in step S3 is placed in a vulcanizer, and then nitrogen at a temperature of 130-150°C is introduced into the system, and vulcanization is performed for 5-10 minutes. Thereafter, nitrogen at 160-170°C is introduced into the system, and vulcanization is performed for 10-15 minutes. Finally, nitrogen at room temperature is introduced, and the temperature is gradually lowered until vulcanization is completed, thereby obtaining a new solid tire for electric forklifts.

[0139] Example 4

[0140] A novel solid tire for electric forklift, the tire comprising a tire liner and a tread rubber,

[0141] The tire liner includes the following substances by mass fraction:

[0142] Natural rubber: 820kg

[0143] Hydrogenated nitrile rubber: 100kg

[0144] Silicone rubber: 30kg

[0145] Shock-absorbing material: 30kg

[0146] Vulcanized material: 10kg

[0147] Palmitic acid: 6kg

[0148] Hexamethylenetetramine: 3kg

[0149] Graphite: 8kg

[0150] N-tert-butyl-2-benzothiazole sulfenamide: 8 kg

[0151] Alumina: 10kg

[0152] The tread rubber includes the following substances by mass fraction:

[0153] Natural rubber: 820kg

[0154] Hydrogenated nitrile rubber: 100kg

[0155] Silicone rubber: 30kg

[0156] Shock-absorbing material: 30kg

[0157] Vulcanized material: 10kg

[0158] Palmitic acid: 6kg

[0159] Hexamethylenetetramine: 3kg

[0160] Graphite: 8kg

[0161] N-tert-butyl-2-benzothiazole sulfenamide: 8 kg

[0162] Alumina: 10kg

[0163] Noise reduction material: 15kg.

[0164] The vulcanizing material is a mixture of 5 kg sulfur and 5 kg tert-butyl hydroperoxide, the shock absorbing material is a mixture of 20 kg EPDM rubber and 10 kg thermoplastic elastomer, and the noise reduction material is a mixture of 7.5 kg chlorobutyl rubber and 7.5 kg white carbon black.

[0165] The method for preparing the novel solid tire for electric forklift comprises the following steps:

[0166] S1: Put the raw material components of the tire liner into an internal mixer, raise the temperature to 50-75°C, and internally mix for 5-8 minutes, then raise the temperature to 140-160°C, internally mix for 10-15 minutes, and finally inject into the tire liner mold to make the tire liner;

[0167] S2: placing the raw material components of the tread rubber into an internal mixer, raising the temperature to 50-75°C, internal mixing for 10-15 minutes, then raising the temperature to 140-150°C, internal mixing for 8-10 minutes, and finally injecting into a tread rubber mold to make the tread rubber;

[0168] S3: The tread rubber obtained in step S2 is adhered to the tire inner liner coated with glue in step S1. After the adhesion is completed, the tire prepared in step S3 is placed in a vulcanizer, and then nitrogen at a temperature of 130-150°C is introduced into the system, and vulcanization is performed for 5-10 minutes. Thereafter, nitrogen at 160-170°C is introduced into the system, and vulcanization is performed for 10-15 minutes. Finally, nitrogen at room temperature is introduced, and the temperature is gradually lowered until vulcanization is completed, thereby obtaining a new solid tire for electric forklifts.

[0169] Comparative Example 1

[0170] Same as Example 3, except that the amount of noise reduction material added is adjusted to 0.

[0171] Comparative Example 2

[0172] The same as in Example 3, except that the sulfurization process in step S3 is changed to ordinary cooling instead of cooling with room temperature nitrogen.

[0173] The properties of the tires prepared in the embodiments of the present invention and the comparative examples are shown in Table 1 below, wherein the resilience is tested in accordance with GB / T1681-2009; the elongation at break is tested in accordance with GB / T10824-2008; the wear resistance index is tested in accordance with GB / T22391-2017; and the noise test is tested in accordance with GB / T32789-1016 after the tires prepared by the present invention are equipped on electric forklifts.

[0174] Table 1 Performance of tires prepared in the embodiments of the present invention and comparative examples

[0175] project Example 1 Example 2 Example 3 Example 4 Comparative Example 1 Comparative Example 2 Resilience, % 25.3 25.4 25.8 26.1 24.4 23.2 Elongation at break, % 582 591 589 596 546 511 Wear resistance index 501 504 503 511 484 411 Noise during vehicle use, decibels 52 53 52 50 66 61

[0176] The following conclusions can be drawn from the above test data: the unique formula of the present invention, combined with the shock-absorbing material, makes the tire of the present invention have excellent performance and lower noise during use. The data of Examples 3 and 4 show that hexamethylenetetramine has better technical effects. The data of Comparative Example 1 shows that the noise increases significantly during use due to the lack of noise-reducing materials. The data of Comparative Example 2 shows that the performance of the tire is reduced by the conventional vulcanization method.

Claims

1. A new type of solid tire for electric forklift, characterized in that: The tire comprises a tire liner and a tread rubber, The tire liner includes the following substances by mass fraction: Natural rubber: 80~90 parts Hydrogenated nitrile rubber: 5~15 parts Silicone rubber: 3~5 parts Shock-absorbing material: 2~4 pieces Vulcanization material: 0.5~2 parts Palmitic acid: 0.1~1 part Anti-aging agent: 0.2~0.5 parts Graphite: 0.5~1 part Accelerator: 0.6~1 part Alumina: 0.3~1.5 parts The tread rubber includes the following substances by mass fraction: Natural rubber: 80~90 parts Hydrogenated nitrile rubber: 5~15 parts Silicone rubber: 3~5 parts Shock-absorbing material: 2~4 pieces Vulcanization material: 0.5~2 parts Palmitic acid: 0.1~1 part Anti-aging agent: 0.2~0.5 parts Graphite: 0.5~1 part Accelerator: 0.6~1 part Alumina: 0.3~1.5 parts Noise reduction material: 1~2 pieces; The noise reduction material is a mixture of chlorinated butyl rubber and white carbon black, and the mass ratio of the chlorinated butyl rubber to the white carbon black is 1:1; The method for preparing the novel solid tire for electric forklift comprises the following steps: S1: Put the raw material components of the tire liner into an internal mixer, raise the temperature to 50-75°C, and internally mix for 5-8 minutes, then raise the temperature to 140-160°C, internally mix for 10-15 minutes, and finally inject into the tire liner mold to make the tire liner; S2: placing the raw material components of the tread rubber into an internal mixer, raising the temperature to 50-75°C, internal mixing for 10-15 minutes, then raising the temperature to 140-150°C, internal mixing for 8-10 minutes, and finally injecting into a tread rubber mold to make the tread rubber; S3: The tread rubber obtained in step S2 is adhered to the tire liner prepared in step S1 coated with glue. After the adhesion is completed, vulcanization is performed to obtain a new solid tire for electric forklifts. The vulcanization process is to place the tire prepared in step S3 in a vulcanizer, and then nitrogen at a temperature of 130-150°C is introduced into the system, and vulcanization is performed for 5-10 minutes. Thereafter, nitrogen at 160-170°C is introduced into the system, and vulcanization is performed for 10-15 minutes. Finally, nitrogen at room temperature is introduced, and the temperature is gradually lowered until the vulcanization is completed.

2. The new solid tire for electric forklift according to claim 1, characterized in that: The vulcanization material is a mixture of sulfur and tert-butyl hydroperoxide, and the mass ratio of the sulfur and tert-butyl hydroperoxide is 1:

1.

3. The new solid tire for electric forklift according to claim 1, characterized in that: The shock-absorbing material is a mixture of EPDM rubber and polyamide thermoplastic elastomer, and the mass ratio of the EPDM rubber to the polyamide thermoplastic elastomer is 2:

1.

4. The new solid tire for electric forklift according to claim 1, characterized in that: The antioxidant is at least one of hexamethylenetetramine, cyclohexylamine and p-fluoroaniline.

5. The new solid tire for electric forklift according to claim 1, characterized in that: The accelerator is N-tert-butyl-2-benzothiazole sulfenamide.