JP2001088922A - Wear resistant conveyor belt - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wear resistant conveyor belt of an excellent wear resistance having an excellent rubber physical property sufficient to convey hard material with a keen jag such as iron ore. SOLUTION: In this wear resistant conveyor belt provided with a covering rubber layer on a conveying plain side to convey an item to be conveyed, the covering rubber layer is composed of rubber composition containing an oil extended rubber of styrene-butadiene copolymer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a wear-resistant conveyor belt.

[0002]

2. Description of the Related Art A conveyor belt used under severe conditions, such as under a chute, for transporting crushed stone, and large iron ore in the early stage of mining, usually requires chip-cut abrasion. Natural rubber is used for such a conveyor belt. Conveyor belts made of these natural rubbers
Due to the difference in polymer structure, rubber properties such as tearing force are superior to a conveyor belt made of styrene-butadiene copolymer rubber (SBR).

[0003] In the case of iron ore under a chute, crushed stone, or large iron ore in the early stage of mining, the conveyor belt which transports these and is required to have abrasion resistance is conventionally made of natural rubber or butadiene rubber. / A blend of natural rubber was used. However, as iron ore and the like are transferred through the conveyor belt, the corners become small. As a result of the investigation, it has been clarified that SBR is superior to natural rubber with respect to mild stimulation such as transport of iron ore having a small angle of about 50 mm or less.

[0004] SBR is inferior in processability, but the processability can be improved by adding oil. However, when the oil is added, the processability of the rubber composition containing SBR as a rubber component is improved, but the rubber properties such as abrasion resistance and tensile strength are lowered. Thus, when SBR is used as the rubber component of the rubber composition, it has been difficult to achieve both rubber properties such as abrasion resistance and tensile strength and workability.

[0005]

DISCLOSURE OF THE INVENTION The present invention provides a conveyor belt using SBR as a rubber component and using a rubber composition as a cover rubber layer which has both rubber properties such as abrasion resistance and tensile strength and workability. It is intended to do so.

[0006]

SUMMARY OF THE INVENTION The present invention is a wear-resistant conveyor belt provided with a cover rubber layer on the side of a conveyed article, wherein the cover rubber layer is an oil-extended styrene-based belt.
It is a wear-resistant conveyor belt made of a rubber composition containing a butadiene copolymer rubber. Hereinafter, the present invention will be described in detail.

The abrasion-resistant conveyor belt of the present invention is provided with a cover rubber layer on the side of the transported material, and the cover rubber layer is a rubber containing oil-extended styrene-butadiene copolymer rubber (SBR). Consists of a composition. The oil-extended SBR refers to SBR in which oil is added at the time of polymerization and polymerization is performed in the presence of the oil, whereby the oil is uniformly dispersed in the polymer and is united with the SBR. The oil-extended SBR is not particularly limited.
R1712 (manufactured by JSR, Nippon Zeon, Sumitomo Chemical, etc.), SBR1714 (manufactured by JSR), SBR177
8 (manufactured by JSR), SBR1778J (manufactured by Zeon Corporation) and the like. The above oil-extended SBR
May be used alone or in combination of two or more. Among these oil-extended SBRs, those obtained by adding 50 parts by weight of a highly aromatic extender oil in advance to 100 parts by weight of a rubber component are preferable.

If the same amount of oil as that contained in the oil-extended SBR is subsequently added to the SBR, the dispersion of carbon black and silica added as reinforcement in the rubber becomes poor, and the resulting rubber composition The tensile strength and tearing force of the object are greatly reduced. In contrast, the oil-extended SB
R does not hinder the dispersion of carbon black or silica because the oil is uniformly dispersed in the polymer.

[0009] The rubber composition may contain another rubber as long as the properties of the oil-extended SBR are not deteriorated. The other rubber is not particularly limited,
For example, SBR, natural rubber, nitrile rubber, etc., which have not been oil-extended in advance, can be mentioned.

[0010] In the wear-resistant conveyor belt of the present invention, 70% by weight or more of the rubber component in the rubber composition is preferably SBR, and 50% by weight or more of the SBR is 100 parts by weight of the rubber component. It is preferably a rubber component of SBR obtained by adding 50 parts by weight of a highly aromatic extender oil in advance. If the SBR is less than 70% by weight of rubber,
The resulting conveyor belt has insufficient abrasion resistance, and the rubber component of SBR, which is obtained by adding 50 parts by weight of a highly aromatic extender oil to 100 parts by weight of the rubber component, has a rubber content of 50% by weight in the SBR. If it is less than 3, workability is insufficient.

The rubber composition further comprises a filler, a vulcanizing agent,
Vulcanization accelerator, carbon black, antioxidant, reinforcing agent,
Tackifiers, processing aids, co-crosslinking agents, crosslinking aids, softeners,
And other additives may be blended.

The vulcanizing agent is not particularly limited, and those usually used in rubber compositions can be used. Such vulcanizing agents include, for example, sulfur, organic peroxides and the like.

When sulfur is used, the amount of the vulcanizing agent is preferably 1 to 3 parts by weight based on 100 parts by weight of the rubber component of the oil-extended SBR. If the amount of sulfur is less than 1 part by weight, vulcanization is insufficient, and if it exceeds 3 parts by weight, elongation at break decreases, crack resistance is adversely affected, and blooming further occurs.

The vulcanization accelerator is not particularly limited.
What is usually used for a rubber composition can be used. Such vulcanization accelerators include, for example, thiazoles, thiurams, dithiocarbamates and the like.

In the present invention, a softener may be further added to the rubber composition constituting the cover rubber layer as long as the rubber properties such as the abrasion resistance of SBR are not impaired. The softener is not particularly limited, and examples thereof include aroma-based process oils. By blending the softening agent, the hardness of the rubber composition can be adjusted and the processability can be further improved.

The total amount of the oil component in the rubber composition is preferably 40 to 60 parts by weight based on 100 parts by weight of the rubber component. The total amount of oil in the rubber composition is 10
When the amount is more than 60 parts by weight with respect to 0 parts by weight, the resulting conveyor belt has insufficient abrasion resistance, and when it is less than 40 parts by weight, the workability is insufficient.

FIG. 1 is a cross-sectional view schematically showing one embodiment of a wear-resistant conveyor belt of the present invention. In addition, this invention is not limited at all by this. As shown in FIG. 1, in a wear-resistant conveyor belt 10 of the present invention, a canvas layer 13 is used as a central layer, and adhesive rubber layers 11 are provided on both sides thereof. The upper and lower outermost layers of the wear-resistant conveyor belt 10 of the present invention are provided with a cover rubber layer 12 and a back cover rubber layer 14, respectively. The cover rubber layer may be a single layer, or two or more layers of the same or different rubber compositions may be laminated.

The rubber composition used for the adhesive rubber layer is not particularly limited, and those usually used for abrasion-resistant conveyor belts can be appropriately selected and used.

The above-mentioned canvas is not particularly limited.
The one used in the abrasion-resistant conveyor belt can be appropriately selected and used, for example, those obtained by applying and infiltrating a rubber paste on a cotton cloth and a synthetic fiber or a synthetic fiber,
RFL-treated ones folded, specially woven nylon canvas, steel cords and the like can be mentioned. The above-mentioned canvas may be used alone, or two or more kinds thereof may be used by laminating them.

The rubber composition used for the back cover rubber layer is not particularly limited, and those usually used for wear-resistant conveyor belts can be appropriately selected and used. Preferred are rubber compositions that contain a spread SBR. The back cover rubber layer may be a single layer or two or more layers of the same or different rubber compositions.

The method for producing the abrasion-resistant conveyor belt of the present invention is not particularly limited, and a commonly used method or the like can be employed. For example, first, the raw materials are kneaded using a Banbury mixer, a kneader mixer, a roll, or the like, and then formed into a sheet using a calendar or the like.
Vulcanization is performed by pressing at a temperature of 0 to 170 ° C. for 10 to 60 minutes to produce each layer such as a cover rubber layer. next,
By laminating the obtained layers on a canvas in a predetermined order, a wear-resistant conveyor belt can be manufactured.

The conveyed material of the conveyor belt of the present invention is not particularly limited, but iron ore, coal, crushed stone, and the like are preferable because the cover rubber layer has excellent physical properties, and particularly small iron ore having a particle size of 50 mm or less. And the like.

By using such a rubber composition for the cover rubber layer, the workability can be improved without impairing the abrasion resistance of the SBR. Extremely good rubber properties such as wear resistance can be provided.

[0024]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples.

Test Example 1 Rubber compositions of Examples 1 to 3 and Comparative Examples 1 to 3 having the composition shown in Table 1 below were prepared. About the obtained rubber composition, various rubber physical properties were evaluated by the following evaluation methods. The results are shown in Table 2.

<Evaluation Method> [Hardness] Measured in accordance with JIS K6253. [Tensile strength] Measured according to JIS K6251. [Elongation] Measured in accordance with JIS K6251. [Abrasion resistance] (1) DIN abrasion amount A DIN abrasion test was performed in accordance with JIS K 6264, and the abrasion amount (mm ³ ) was measured. (2) Lambourn Abrasion A Lambourn abrasion test was performed in accordance with JIS K 6264, and the abrasion (g / km) was measured at a slip ratio of 20%.

[0027]

[Table 1]

The components in Table 1 are as follows. SBR1500: Styrene-butadiene copolymer rubber (manufactured by JSR) SBR1712: Styrene-butadiene copolymer rubber (manufactured by JSR) in which 37.5 parts by weight of a highly aromatic extender oil is oil-extended with respect to 100 parts by weight of SBR. SBR1714: Styrene-butadiene copolymer rubber (manufactured by JSR) oil-extended with 50 parts by weight of highly aromatic extender oil per 100 parts by weight of SBR Carbon black: N220 (manufactured by Showa Cabot) Oil: Syntax HA30 (aroma) Anti-aging agent: 2 parts by weight of Nocrac6C (N- (1,3-dimethyl-butyl) -N′-phenyl-p-phenylenediamine, manufactured by Ouchi Shinko Chemical Co., Ltd.) and paraffin 2 Parts by weight Tackifier: Coumarone / Indene resin Vulcanization accelerator: Noxeller CZ (N-cyclohexyl) 2
-Benzothiazyl-sulfenamide, manufactured by Ouchi Shinko Chemical Co., Ltd.)

[0029]

[Table 2]

Test Example 2 Using the rubber compositions of Examples 1 to 3 and Comparative Examples 1 to 3 for the cover rubber layer and the back cover rubber layer, a conveyor belt having a structure as shown in FIG. 1 was produced. did. The obtained conveyor belt was used for transporting iron ore, and the change in the thickness of the cover rubber layer on the transport surface (table) at that time was measured. The results are shown in Table 3. The size of the conveyor belt used for the test was as follows. Width: 600mm Thickness of cover rubber layer: 5mm Thickness of back cover rubber layer: 3mm

The test conditions were as follows. Test time: 300 hours Test speed: 200 m / min Iron ore transport: about 800 t / hour Size of iron ore: Particle size 50 mm or less

[0032]

[Table 3]

After the test, in the conveyor belt using the rubber composition of Comparative Example 1 for the cover rubber layer, the wear amount of the cover rubber layer was 1.5 mm in thickness, whereas the belts of Examples 1 to 3 were worn. Conveyor belt using rubber composition for cover rubber layer,
The wear amount of the cover rubber layer was 0.4 to 0.6 mm, and was about 1 / 2.5 to 1/3 of that of Comparative Example 1. Conveyor belts using the rubber compositions of Comparative Examples 2 and 3 having inferior tensile strength for the cover rubber layer are:
Cracks occurred during running and running tests on these conveyor belts were discontinued.

[0034]

According to the present invention, SBR is used as a rubber component.
By using the above, a wear-resistant conveyor belt using a rubber composition having both rubber properties such as abrasion resistance and tensile strength and workability as a cover rubber layer can be obtained.

[Brief description of the drawings]

FIG. 1 is a sectional view showing one embodiment of a wear-resistant conveyor belt of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Abrasion-resistant conveyor belt 11 Adhesive rubber layer 12 Cover rubber layer 13 Canvas layer 14 Back cover rubber layer

Claims (3)

[Claims] An abrasion-resistant conveyor belt provided with a cover rubber layer on the side of a conveyed material, wherein the cover rubber layer is made of a rubber composition containing an oil-extended styrene-butadiene copolymer rubber. A wear-resistant conveyor belt characterized by the following. 2. 70% by weight or more of the rubber component in the rubber composition is a styrene-butadiene copolymer rubber, and 50% by weight or more of the styrene-butadiene copolymer rubber is
2. The rubber component of a styrene-butadiene copolymer rubber obtained by adding 50 parts by weight of a highly aromatic extender oil to 100 parts by weight of a rubber component in advance.
The described wear-resistant conveyor belt. 3. The total amount of the oil component in the rubber composition is 1 rubber component.
The wear-resistant conveyor belt according to claim 1 or 2, wherein the amount is 40 to 60 parts by weight based on 00 parts by weight.