High-performance ozone-resistant air spring and preparation method thereof

Abstract

The invention discloses a high-performance ozone-resistant air spring and a preparation method thereof. An inner-layer rubber material and an outer-layer rubber material of the air spring are mainly prepared from the following components: chloroprene rubber, natural rubber, butadiene rubber, an anti-aging agent AW-66, an anti-aging agent 4010NA, an anti-aging agent 4020, microcrystalline wax, N660 carbon black, naphthenic oil, zinc oxide, CZ and insoluble sulfur. The preparation method comprises the steps of first-stage mixing, rubber discharging, standing, second-stage mixing, rubber discharging, standing, rubber sheet calendering, blastocyst forming, wrapping the blastocyst on the surface of a capsule, and performing high-pressure nitrogen vulcanization to form the air spring. The chloroprene rubber, the natural rubber and the butadiene rubber are blended and modified, so that the rubber has the following characteristics that the ozone resistance and the weather aging resistance are remarkably improved; the properties such as tensile strength, stress at definite elongation and tear resistance are improved; the production process properties such as extrusion and calendaring properties are improved, the deflection resistance of the rubber material is improved, and the service life of the product is prolonged.

Description

Technical Field

[0001] The invention relates to an air spring processing and manufacturing technology, in particular to a sleeve-type cab air spring and a preparation method thereof. Background Art

[0002] With the rapid development of modern industry, air springs, as an important elastic component, are widely used in vehicle suspension, mechanical buffer and other fields. Ozone resistance is one of the key indicators to measure the service life and performance stability of air springs. Therefore, studying and optimizing an air spring formula with excellent ozone resistance is of great significance to improving product quality and extending service life. Summary of the invention

[0003] In view of the use conditions and use requirements of air springs, the present invention provides a high-performance ozone-resistant air spring and a preparation method thereof. The air spring of the present invention adopts inner and outer layer rubber materials with the same formula rubber material, which can not only ensure that the inner layer rubber material has good air tightness, but also ensure that the outer layer rubber material has good ozone resistance, weather resistance and fatigue resistance. Therefore, the main material of the present invention adopts chloroprene rubber with good ozone resistance, combined with natural rubber with good comprehensive performance and butadiene rubber with low heat generation and good flexural resistance, and adds appropriate amounts of antioxidants, anti-ultraviolet agents and other additives to further improve the ozone resistance of the outer layer rubber material.

[0004] The technical solution adopted by the present invention is as follows:

[0005] The present invention provides a high-performance ozone-resistant air spring, the inner and outer layers of which are made of the same rubber material, and the material components and mass percentages are as follows:

[0006]

[0007]

[0008] The carbon black mentioned above is N660 carbon black; the plasticizer is cyclohexane oil; the antioxidants are antioxidant AW-66, antioxidant 4010NA, antioxidant 4020 and microcrystalline wax; the vulcanizing agent is insoluble sulfur; the activator is indirect zinc oxide; and the accelerator is CZ.

[0009] Based on the above specific materials, the mass percentages are as follows:

[0010]

[0011] Furthermore, the chloroprene rubber is a non-sulfur-adjusted type, with a Mooney viscosity of 46-55; the natural rubber is a common standard rubber, and the butadiene rubber is a low-cis butadiene rubber.

[0012] The present invention also provides a preparation method of the high-performance ozone-resistant air spring, which includes a first-stage rubber mixing process and a second-stage rubber mixing process. In the first-stage rubber mixing stage, carbon black, an antioxidant, and a plasticizer are added on the basis of first adding chloroprene rubber, natural rubber, and butadiene rubber for mixing; in the second-stage rubber mixing stage, insoluble sulfur as a vulcanizing agent and CZ as an accelerator are added.

[0013] The specific steps include:

[0014] 1) One-stage rubber mixing

[0015] S1, the chloroprene rubber, natural rubber and butadiene rubber of the above-mentioned set mass percentage are mixed using a 410 liter internal mixer for 50-70 seconds;

[0016] S2, adding antioxidant 4010NA, antioxidant AW-66, antioxidant 4020, microcrystalline wax and N660 carbon black to the mixing step S1 and mixing for 40-60 seconds;

[0017] S3, adding naphthenic oil on the basis of steps S1 and S2 and continuing mixing, the mixing time is 40-60 seconds;

[0018] S4, on the basis of step S3, continue mixing after lifting the ball, the mixing time is 30-50 seconds;

[0019] 2) One section of glue

[0020] The mixed rubber is discharged at a temperature of 130-140℃;

[0021] 3) Let it stand

[0022] Leave a section of discharged glue for 24 hours;

[0023] 4) Second stage rubber mixing

[0024] After the first stage of rubber has been parked for 24 hours, add the set mass percentage of insoluble sulfur, zinc oxide and CZ to carry out two-stage mixing, and the mixing time is 4-6 minutes;

[0025] 5) Second stage glue removal

[0026] The mixed second stage rubber is discharged at a temperature of 85-95°C;

[0027] 6) Let it stand

[0028] Leave the glue discharged from the second stage for 24 hours;

[0029] 7) Press out the film

[0030] The second stage rubber that has been parked for 24 hours is extruded into a film of a certain width and thickness through a die and a die by a cold feed extruder. After cooling, it is rolled and wrapped on the I-shaped wheel with a cord fabric.

[0031] 8) Molding

[0032] On the finished product head of specified diameter, an inner layer of film, two layers of cords staggered at fixed angles and an outer layer of film are wrapped in sequence so that they fit tightly together and are compacted to form a blastocyst.

[0033] 9) Vulcanization molding

[0034] The blastocyst is placed in a special capsule and placed in a vulcanizer, where it is pre-shaped, shaped by high-pressure nitrogen, and vulcanized into a product.

[0035] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0036] 1. The present invention utilizes the advantages of chloroprene rubber, natural rubber and butadiene rubber to form complementary advantages and produce the inner and outer layer rubber materials of the air spring.

[0037] 2. Neoprene has good performance in terms of ozone resistance, weathering resistance, air tightness, tensile strength, etc. Natural rubber has comprehensive performance, with good wear resistance, high elasticity, tear strength and elongation. Butadiene has good processing performance, excellent wear resistance and elasticity, less heat generation, and good flex resistance. Through the blending and modification of the three, the blended rubber has the following characteristics: significantly improved ozone resistance and weathering resistance; improved tensile strength, tensile stress, tear resistance and other properties; improved extrusion, calendering performance and other production process performance, while improving the flex resistance of the rubber material, extending the service life of the product.

[0038] 3. The present invention adopts N660 carbon black with smaller particle size, which is easy to disperse in the rubber material. The vulcanized rubber has higher tensile strength, tear strength and tensile stress, smaller deformation, lower heat generation, good elasticity and flexural resistance, thus avoiding premature aging of the air spring due to excessive heat generation due to flexing during use.

[0039] 4. The present invention adopts an antioxidant with good ozone resistance, which can effectively inhibit the corrosion of ozone on rubber and delay the aging process of the product, thereby increasing the service life of the air spring.

[0040] Other features and advantages of the present invention will be set forth in the following description, and in part will be apparent from the description, or may be learned by practicing the present invention. DETAILED DESCRIPTION

[0041] The present invention is described in detail below in conjunction with the embodiments. However, those skilled in the art should know that the following embodiments are not the only limitations on the technical solutions of the present invention, and any equivalent changes or modifications made under the spirit of the technical solutions of the present invention should be deemed to belong to the protection scope of the present invention.

[0042] The invention aims to produce an air spring by blending chloroprene rubber, natural rubber and butadiene rubber, thereby improving the ozone resistance of the rubber material and ensuring the flexural aging resistance of the product.

[0043] After continuous experiments and exploration, the present invention provides a high-performance ozone-resistant air spring, the inner and outer rubber layers of which are made of the same material, and the material components and mass percentages are as follows:

[0044]

[0045]

[0046] Further:

[0047] The carbon black is N660 carbon black;

[0048] The plasticizer is naphthenic oil;

[0049] The antioxidants are antioxidant AW-66, antioxidant 4010NA, antioxidant 4020 and microcrystalline wax; the vulcanizing agent is insoluble sulfur;

[0050] The active agent is indirect zinc oxide;

[0051] The accelerator is CZ.

[0052] Based on the above materials, we further:

[0053]

[0054] Furthermore: the chloroprene rubber is a non-sulfur-adjusted type, and has a Mooney viscosity of 46-55.

[0055] Furthermore: the natural rubber is common standard rubber, and the butadiene rubber is low-cis butadiene rubber.

[0056] Neoprene, natural rubber and butadiene rubber are the main materials used as the inner and outer rubber materials of the air spring; insoluble sulfur is the vulcanizing agent for the vulcanized inner and outer rubber materials of the air spring; CZ is the accelerator for the vulcanized inner and outer rubber materials of the air spring; zinc oxide is the activator for the vulcanized inner and outer rubber materials of the air spring; N660 carbon black is the reinforcing material for the inner and outer rubber materials of the air spring; cyclohexane oil is the plasticizer for the rubber; antioxidant AW-66, antioxidant 4010NA, antioxidant 4020 and microcrystalline wax are used as antioxidants for the inner and outer rubber materials of the air spring.

[0057] The present invention uses non-sulfur-adjusted chloroprene rubber (W type) with a Mooney viscosity of 46-55. The main chain of this type of molecule does not contain a polysulfide chain, so the storage stability is good. Compared with sulfur-adjusted chloroprene rubber, the advantages are that it is not easy to burn and stick to the roller during processing, the operating conditions are easy to control, and the vulcanized rubber has good heat resistance and low compression deformation.

[0058] Natural rubber is a common standard rubber, and cis-1,4-butadiene rubber is low-cis-1,4-butadiene rubber. Low-cis-1,4-butadiene rubber has excellent cold resistance, resilience, wear resistance, aging resistance and oil resistance, especially the best low-temperature flexural resistance. In addition, it has the characteristics of light color, transparency, no gel and high purity.

[0059] The invention selects chloroprene rubber, natural rubber and butadiene rubber for blending and modification. Through the blending and modification of the three, the blended rubber has the following characteristics: significantly improved ozone resistance and weathering resistance; improved tensile strength, tensile stress, tear resistance and other properties; improved production process properties such as extrusion and calendering properties, while improving the flexural resistance of the rubber material and extending the service life of the product.

[0060] The present invention adopts N660 carbon black with smaller particle size, which is easy to disperse in the rubber material. The vulcanized rubber has higher tensile strength, tear strength and tensile stress, smaller deformation, lower heat generation, good elasticity and flexural resistance, thus avoiding premature aging of the air spring due to excessive heat generation due to flexing during use.

[0061] The present invention adopts an antioxidant with good ozone resistance, which can effectively inhibit the corrosion of ozone on rubber and delay the aging process of the product, thereby increasing the service life of the air spring.

[0062] The present invention also provides a method for preparing a high-performance ozone-resistant air spring, comprising first-stage rubber mixing and second-stage rubber mixing, characterized in that:

[0063] In the first stage of rubber mixing, carbon black, antioxidant and plasticizer are added on the basis of adding chloroprene rubber, natural rubber and butadiene rubber first; in the second stage of rubber mixing, insoluble sulfur, activator zinc oxide and accelerator CZ are added.

[0064] The specific refining process is as follows:

[0065] 1) One-stage rubber mixing

[0066] S1, the chloroprene rubber, natural rubber and butadiene rubber of the above-mentioned set mass percentage are mixed using a 410 liter internal mixer for 50-70 seconds;

[0067] S2, adding antioxidant 4010NA, antioxidant AW-66, antioxidant 4020, microcrystalline wax and N660 carbon black to the mixing step S1 and mixing for 40-60 seconds;

[0068] S3, adding naphthenic oil on the basis of steps S1 and S2 and continuing mixing, the mixing time is 40-60 seconds;

[0069] S4, on the basis of step S3, continue mixing after lifting the ball, the mixing time is 30-50 seconds;

[0070] 2) One section of glue

[0071] The mixed rubber is discharged at a temperature of 130-140℃;

[0072] 3) Let it stand

[0073] Leave a section of discharged glue for 24 hours;

[0074] 4) Second stage rubber mixing

[0075] After the first stage of rubber has been parked for 24 hours, add the set mass percentage of insoluble sulfur, zinc oxide and CZ to carry out two-stage mixing, and the mixing time is 4-6 minutes;

[0076] 5) Second stage glue removal

[0077] The mixed second stage rubber is discharged at a temperature of 85-95°C;

[0078] 6) Let it stand

[0079] Leave the glue discharged from the second stage for 24 hours;

[0080] 7) Press out the film

[0081] The second stage rubber that has been parked for 24 hours is extruded into a film of a certain width and thickness through a die and a die by a cold feed extruder. After cooling, it is rolled and wrapped on the I-shaped wheel with a cord fabric.

[0082] 8) Molding

[0083] On the finished product head of specified diameter, an inner layer of film, two layers of cords staggered at fixed angles and an outer layer of film are wrapped in sequence so that they fit tightly together and are compacted to form a blastocyst.

[0084] 9) Vulcanization molding

[0085] The blastocyst is placed in a special capsule and placed in a vulcanizer, where it is pre-shaped, shaped by high-pressure nitrogen, and vulcanized into a product.

[0086] The finished air spring is tested for physical properties, mainly testing its strength, elongation, hardness, permanent deformation and other performance parameters. The following are several examples.

[0087] Example 1: Mixing was performed with the following material components in percentage by mass:

[0088]

[0089] Example 2: Mixing was performed with the following material components in percentage by mass:

[0090]

[0091]

[0092] Example 3: Mixing was performed with the following material components in percentage by mass:

[0093] Comparing the three embodiments, the performance parameters obtained are compared as follows:

[0094]

[0095]

[0096] From the above comparison, it can be seen that with the increase of the proportion of chloroprene rubber in the rubber compound, although the physical and mechanical properties of the rubber compound have decreased, the ozone aging resistance of the rubber compound has been significantly improved, and the fatigue life has not decreased. Therefore, using this formula as the inner and outer layer rubber formula of the air spring can not only ensure the performance of the product, but also ensure that it can maintain a good use state in an environment with relatively high ozone concentration, thereby avoiding product failure due to premature ozone aging.

Claims

1. A high performance ozone resistant air spring, characterized in that: The inner and outer layers are made of the same rubber material, and the material composition and mass percentage are as follows:

2. The high performance ozone resistant air spring according to claim 1, characterized in that: The carbon black is N660 carbon black; The plasticizer is naphthenic oil; The antioxidants are antioxidant AW-66, antioxidant 4010NA, antioxidant 4020 and microcrystalline wax; The vulcanizing agent is insoluble sulfur; The active agent is indirect zinc oxide; The accelerator is CZ.

3. The high performance ozone resistant air spring according to claim 2, characterized in that: The composition includes the following mass percentages:

4. The high performance ozone resistant air spring according to claim 1, 2 or 3, characterized in that: The chloroprene rubber is a non-sulfur-adjusted type with a Mooney viscosity of 46-55; The natural rubber is common standard rubber, and the butadiene rubber is low-cis butadiene rubber.

5. A method for preparing a high-performance ozone-resistant air spring as claimed in any one of claims 1 to 4, comprising a first-stage rubber mixing process and a second-stage rubber mixing process, characterized in that: In the first rubber mixing stage, after adding chloroprene rubber, natural rubber and butadiene rubber, carbon black, antioxidant and plasticizer are added; In the second stage of rubber mixing, insoluble sulfur as a vulcanizing agent and CZ as an accelerator are added.

6. The preparation method according to claim 5, characterized in that: The specific steps include: 1) One-stage rubber mixing S1, the chloroprene rubber, natural rubber and butadiene rubber of the above-mentioned set mass percentage are mixed using a 410 liter internal mixer for 50-70 seconds; S2, adding antioxidant 4010NA, antioxidant AW-66, antioxidant 4020, microcrystalline wax and N660 carbon black to the mixing step S1 and mixing for 40-60 seconds; S3, adding naphthenic oil on the basis of steps S1 and S2 and continuing mixing, the mixing time is 40-60 seconds; S4, on the basis of step S3, continue mixing after lifting the ball, the mixing time is 30-50 seconds; 2) One section of glue The mixed rubber is discharged at a temperature of 130-140℃; 3) Let it stand Leave a section of discharged glue for 24 hours; 4) Second stage rubber mixing After the first stage of rubber has been parked for 24 hours, add the set mass percentage of insoluble sulfur, zinc oxide and CZ to carry out two-stage mixing, and the mixing time is 4-6 minutes; 5) Second stage glue removal The mixed second stage rubber is discharged at a temperature of 85-95°C; 6) Let it stand Leave the glue discharged from the second stage for 24 hours; 7) Press out the film The second stage rubber that has been parked for 24 hours is extruded into a film of a certain width and thickness through a die and a die by a cold feed extruder. After cooling, it is rolled and wrapped on the I-shaped wheel with a cord fabric. 8) Molding On the finished product head of specified diameter, an inner layer of film, two layers of cords staggered at fixed angles and an outer layer of film are wrapped in sequence so that they fit tightly together and are compacted to form a blastocyst. 9) Vulcanization molding The blastocyst is placed in a special capsule and placed in a vulcanizer, where it is pre-shaped, shaped by high-pressure nitrogen, and vulcanized into a product.

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