JPH1036566A - Conveying belt - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a conveying belt which can prevent muddy, powdery or block substance from adhering or sticking to the belt. SOLUTION: In this conveying belt prepared by embedding a tension member (core material) in the covering rubber, the first conveying belt is composed of a vulcanized rubber containing the rubber component more than 30wt.% and having an impact resilience of >=65%. The second conveying belt having a non-adherent surface is composed of a vulcanized rubber containing the rubber component more than 50wt.% and having an impact resilience of >=65%. This vulcanized rubber is prepared by vulcanizing a rubber compound containing 5-50 pts.wt. of at least any of (a) carbon black with an average particle size of >=55nm, (b) carbon black with an average particle size of 30 <= size <=55nm, and (c) carbon black with an average particle size of <=30nm, in total per 100 pts.wt. of rubber.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a conveyor belt,
More specifically, the present invention relates to a transport belt to which mud, powder, lumps and the like hardly adhere to the surface thereof, that is, a transport belt having excellent surface non-adhesiveness.

[0002]

2. Description of the Related Art When conveying a sludge, a powdery granular material, and a lump mass by a conveyance belt, the conveyance material adheres or adheres to the belt, and the entire amount is released from the belt at a regular release (release or release) position. Not often happens. The conveyed material that has not been released from the belt in this way adheres to the belt, lowers the conveying capacity of the belt, or falls off the belt irregularly in the return (on the way back to the position where the conveyed product is loaded), Since the periphery of the conveyor belt is soiled, measures such as maintenance and cleaning of the belt and cleaning of the periphery of the belt are required, resulting in an increase in transportation costs.

[0003] Such a problem of the adhesion of the conveyed material on the conveyor belt has been a fundamental problem in the conveyor belt. Particularly, the conveyor belt contains a large amount of viscous bitumen and is extremely adhered to the surface of the conveyor belt. Various belts for transporting an oil sand which is easy to carry have a non-adhesive surface. For example, JP-A-58-19
No. 8547 describes a transport belt having a surface layer of a vulcanized rubber obtained by sulfur-vulcanizing SBR, NBR or the like with natural rubber containing silicone raw rubber. In addition, special fair 3
JP-A-14062 and the like describe that a surface layer is formed of a rubber material in which a higher fatty acid ester is blended with NBR.

[0004] However, for general-purpose transport belts other than such oil sand transport belts, only a very small number of proposals have been made to detackify the surface. As one of such proposals, Shokai Sho 59-1
No. 33508 discloses a conveyor belt in which the sticking of a thermoplastic elastomer to the surface prevents the sticking of a viscous cake, but as such, its non-adhesiveness is not sufficient. is not. In addition, Japanese Unexamined Patent Publication
In the publication 1-1010174, grease-like or oil-like silicone is compounded into raw rubber, and this is vulcanized and molded.
Although it is described as a transport belt, its non-adhesiveness is not sufficient.

[0005]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems in the conventional non-adhesive transport belt, and provides a transport belt having excellent surface non-adhesiveness. The purpose is to do.

[0006]

According to the first aspect of the present invention, there is provided a conveyor belt having a core body embedded in a cover rubber, wherein the cover rubber has a rubber content of 30% by weight or more. It is made of vulcanized rubber having an elastic modulus of 65% or more. The second aspect of the non-adhesive transport belt according to the present invention is a transport belt having a core body embedded in a cover rubber, wherein the cover rubber has a rubber content of 50% by weight or more and a rebound resilience of 65% or more. This vulcanized rubber is 100 parts by weight of rubber, (a) carbon black having an average particle diameter of 55 nm or more, (b) carbon black having an average particle diameter of 30 nm or more and less than 55 nm, (c)
It is a vulcanized rubber obtained by vulcanizing a rubber compound containing at least one of carbon black having an average particle diameter of less than 30 nm in a total amount of 5 to 50 parts by weight.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In general, as shown in FIG. 1, a conveyor belt has a core body 3 embedded between an upper cover rubber 1 and a lower cover rubber 2, and this core body is shown in FIG. As described above, a steel cord is used, and a canvas is also used. A first aspect of the transport belt according to the present invention is that in a transport belt having a core body embedded in a cover rubber, the cover rubber is made of vulcanized rubber having a rubber content of 30% by weight or more and a rebound resilience of 65% or more. Features. In the present invention, the rebound resilience is a value measured by a rebound resilience test specified in JIS K6301-1995, "Vulcanized Rubber Physical Test Method".

According to the present invention, as described above, by using a vulcanized rubber having a rubber content of 30% by weight or more and a rebound resilience of 65% or more as the cover rubber of the transport belt,
When a conveyed object is dropped onto the conveyor belt from the shooter and supplied, the high resilience of the belt surface prevents adhesion of the conveyed object to the belt surface, and also causes the belt to drop from the belt at the release (release or release) position. When releasing the belt, the high rebound resilience of the belt surface makes it possible to throw off the cargo, so to speak, so that mud, powder,
It is possible to effectively prevent the lump or the like from adhering or sticking to the belt surface.

According to the present invention, the cover rubber preferably comprises at least 50% by weight of natural rubber, and more preferably the cover rubber comprises natural rubber. However, when the rubber is a mixture with natural rubber, the other rubber is preferably, for example, styrene-butadiene rubber (SBR). In general, rubber itself is inferior in processability, so that various fillers are usually blended to reduce green strength and improve processability, but on the other hand, fillers are added to rubber in this way. If you mix
This results in a decrease in the rebound resilience of the vulcanized rubber, and as a result, the adhesion of the muddy material, the powdery granular material, the aggregated material, etc. to the vulcanized rubber is increased.

However, according to the present invention, the rubber forming the cover rubber is blended with calcium carbonate as a filler within a predetermined range, thereby ensuring the resilience of the obtained vulcanized rubber while at the same time processing the rubber. The transfer belt having excellent surface non-adhesion can be obtained by improving the properties. According to the present invention, the compounding amount of calcium carbonate in the rubber is in the range of 15 to 200 parts by weight, preferably in the range of 30 to 100 parts by weight, per 100 parts by weight of the rubber.
If the amount of calcium carbonate in the rubber is less than 15 parts by weight per 100 parts by weight of the rubber, the resulting vulcanized rubber is excellent in rebound resilience but inferior in processability. On the other hand, when the compounding amount of calcium carbonate to natural rubber is more than 200 parts by weight per 100 parts by weight of rubber, the obtained vulcanized rubber not only has poor rebound resilience but also has poor processability. Become.

The addition of a reinforcing agent to the rubber also usually reduces the rebound resilience of the vulcanized rubber. However, according to the present invention, carbon black having a predetermined average particle diameter is compounded in a predetermined range. Thereby, the strength of the obtained vulcanized rubber can be increased, and a decrease in rebound resilience can be prevented, so that a transport belt having excellent surface non-adhesion can be obtained. That is,
According to the first aspect of the transport belt of the present invention, the compounding amount of carbon black is as follows: (a) carbon black having an average particle diameter of 55 nm or more;
The total amount of at least one of carbon black of 0 nm or more and less than 55 nm and (c) carbon black having an average particle diameter of less than 30 nm is 5 parts by weight or less.

Examples of carbon black having an average particle diameter of 55 nm or more include FT (average particle diameter of 150 nm),
SRF (average particle diameter 65 nm), GPF (average particle diameter 5
5 nm). The upper limit is usually 30
0 nm. Examples of the carbon black having an average particle diameter of 30 nm or more and less than 55 nm include HMF (average particle diameter 52 nm), FF (average particle diameter 50 nm), and FEF.
(Average particle diameter of 38 nm). Examples of the carbon black having an average particle size of less than 30 nm include HAF (average particle size 30 nm), ISAF (average particle size 28 nm), and SAF (average particle size 18 nm). The lower limit is usually 5 nm. The average particle size of the carbon black is based on the Rubber Industry Handbook, 4th edition, page 500, issued by The Rubber Association of Japan.

Next, the second of the conveyor belts according to the present invention is as follows.
In a conveyor belt having a core embedded in a cover rubber, the cover rubber has a rubber content of 50% by weight or more and a rebound resilience of 6%.
5% or more of a vulcanized rubber, wherein the vulcanized rubber is (a) carbon black having an average particle diameter of 55 nm or more, (b) an average particle diameter of 30 nm or more,
Carbon black less than 5 nm, (c) average particle diameter 30 n
m is a vulcanized rubber obtained by vulcanizing a rubber compound containing at least one of carbon blacks having a total amount of 5 to 50 parts by weight in total.

The carbon black having the above average particle diameter is as described above. Also in the second transport belt of the present invention, it is preferable that at least 50% by weight of the cover rubber is natural rubber, and it is particularly preferable that the cover rubber be made of natural rubber.
Furthermore, according to the second of the conveying belts of the present invention, the rubber 100
In terms of parts by weight, carbon black is blended in the above-mentioned range, and 15 to 90 parts by weight of calcium carbonate is blended and vulcanized to have a rebound resilience of 65% or more, so that the rubber compound has excellent workability. In addition, the vulcanized rubber is excellent not only in surface non-adhesion, but also in abrasion resistance and strength, so that it is possible to obtain a practically non-adhesive transport belt with excellent practicality.

According to the present invention, in addition to the above-mentioned calcium carbonate as a filler and carbon black as a reinforcing agent, a conventionally known rubber compounding agent is compounded into rubber, and the rubber is vulcanized. It can be a surface layer. As such a compounding agent, for example, a vulcanizing agent, a vulcanizing aid,
Antioxidants, reinforcing agents, fillers, plasticizers, process oils, tackifiers and the like can be mentioned.

Such compounding agents include, for example, vulcanizing agents such as sulfur, fillers such as talc, silicic anhydride, hydrated silicic acid, accelerating activators such as zinc oxide, stearic acid and minerals. A softening agent such as oil or a plasticizer can be used. The conveying belt according to the present invention is obtained by adding a conventional compounding agent to rubber according to a conventionally known conventional method,
If necessary, it can be obtained by further blending calcium carbonate or carbon black and molding the obtained rubber compound into a conveyor belt. Usually, canvas or steel cord is used as the body.

Conventionally, in order to prevent the transported material from adhering to the surface of the transport belt, when the belt is driven, various stresses and impacts are applied to the belt to cause the transported product to drop from the belt surface, and the transported material is moved from the belt surface. It is known to adhere to and prevent deposition. When the transport belt according to the present invention is used for transport while applying various stresses and impacts in driving as described above, it is possible to more effectively prevent the transported material from adhering to the surface of the transport belt.

[0018]

As described above, according to the first aspect of the present invention,
In a conveyor belt having a core body embedded in a cover rubber, the cover rubber has a rubber content of 30% by weight or more and a rebound resilience of 6%.
When the conveyed material is supplied to the belt surface by being formed from the vulcanized rubber which is 5% or more, and when the conveyed material is released from the belt at the release position, the conveyed material is made to have a high rebound resilience. It can be effectively prevented from adhering to the surface.

Further, according to the second aspect of the present invention, in a transport belt having a core buried in a cover rubber, the cover rubber contains carbon black, and the rubber content is 50% by weight or more.
By forming it from a vulcanized rubber having a rebound resilience of 65% or more, it is possible to obtain a surface-adhesive transport belt having excellent mechanical strength.

[0020]

EXAMPLES The present invention will be described below with reference to examples.
The present invention is not limited by these examples.

Example I (First Example of the Present Invention) A rubber compound was prepared by the compounding method shown in Tables 1 and 2, and kneaded.
Vulcanization for 5 minutes, size 15cm × 15cm,
A test piece having a thickness of 2 mm was prepared.

Calcium sulfate dihydrate (special reagent grade) is transported by a transport belt, and the amount of adhering to the belt is determined as follows.
It measured according to the method described in 14062 gazette. That is, as shown in FIG. 2, cuts are made in several places of the endless belt 4 and the test piece 5 is set on the surface of the belt to form a test belt, and the belt is run at 40 m / min. Calcium sulfate dihydrate 7 was continuously dropped from the hopper 6 above the belt at a rate of 35 g / min onto the belt, and the press roll 8 pressed the calcium sulfate dihydrate against the belt surface for 30 minutes. Was.
Thereafter, the amount of calcium sulfate dihydrate adhering to the test piece was measured.

The amount of adhesion to the test piece was determined by vulcanizing a rubber compound obtained by mixing 40 parts by weight of carbon black (HAF) with 100 parts by weight of natural rubber by the above-described method. It is shown as a relative value when the adhesion amount of calcium sulfate dihydrate measured according to the above method using (Reference Example in Table 1) is 100. In the column of the amount of adhesion to the conveyor belt, A indicates that when the test piece was used for the test as it is, B indicates
The case where the surface of the test piece was polished and roughened and then used for the test is shown. With the use of the transport belt, the surface of the transport belt is worn by a transported object or a pulley, and the unevenness becomes significant, so that the transported item is easily attached. The reason why the surface of the test piece was polished and roughened was to examine the amount of calcium sulfate dihydrate adhering when the transport belt was worn.

The rubber processability was evaluated by forming the rubber into a sheet having a thickness of 1.0 mm using an open roll, and evaluating the smoothness of the surface of the obtained sheet, that is, the uniformity of the thickness. ○ is uniform, △ is slightly uneven, ×
Indicates non-uniform. The results are shown in Tables 1 and 2.

[0025]

[Table 1]

[0026]

[Table 2]

According to Comparative Examples 1 to 3 and Examples 1 to 10, according to the present invention, according to the present invention, according to the conveyor belt made of vulcanized rubber having a rubber content of 30% by weight or more and a rebound resilience of 65% or more according to the present invention, Adhesion can be significantly reduced. In particular, according to the present invention, by blending 15 to 200 parts by weight of calcium carbonate with 100 parts by weight of rubber, while improving the rebound resilience of the obtained vulcanized rubber, the processability of the rubber compound is improved and the cover is improved. It can be rubber. When using silicic anhydride or talc as a filler instead of calcium carbonate, the resilience of the resulting vulcanized rubber is 60% or less, even though the processability of the rubber can be enhanced, and the transport belt is Great adhesion of transported goods.

Example II (Second Example of the Present Invention) A rubber compound was prepared by the compounding shown in Tables 3 and 4, and kneaded.
Vulcanization for 5 minutes, size 15cm × 15cm,
A test piece having a thickness of 2 mm was prepared.

In the same manner as in Example I, the amount of calcium sulfate dihydrate adhering to the test piece was measured. The amount of adhesion to the test piece was the same as in Example I, except that carbon black (HAF)
Adhesion of calcium sulfate dihydrate measured according to the method described above using a test piece (Comparative Example 2 in Table 3) obtained by vulcanizing a rubber compound containing 40 parts by weight according to the method described above. It is shown as a relative value when the amount is 100. The results are shown in Tables 3 to 5.

[0030]

[Table 3]

[0031]

[Table 4]

[0032]

[Table 5]

According to Comparative Examples 1 to 6 and Examples 1 to 13, according to the present invention, according to the present invention, the cover rubber is made of a vulcanized rubber having a rubber content of 50% by weight or more and a rebound resilience of 65% or more. Adhesion can be significantly reduced. In particular, according to the present invention, a rubber is blended with carbon black having a predetermined average particle diameter in a predetermined range, and vulcanized to form a cover rubber. Thus, a practical transport belt can be obtained with improved target strength.

When the carbon black specified in the present invention is not blended in a predetermined range, the rebound resilience of the vulcanized rubber is set to 65.
%, And as a result, the transport belt has a high adherence of the transported object.

[Brief description of the drawings]

FIG. 1 is a sectional view of a transport belt.

FIG. 2 is a schematic view showing an apparatus for checking the adhesion of a conveyed material to a belt.

[Explanation of symbols]

1 top cover rubber, 2 bottom cover rubber, 3 core,
4: Endless belt, 5: Test piece, 6: Hopper,
7 ... calcium sulfate dihydrate, 8 ... press roll.

──────────────────────────────────────────────────続 き Continuation of the front page (51) Int.Cl. ⁶ Identification number Agency reference number FI Technical indication location C08L 7/00 C08L 7/00

Claims (9)

[Claims] 1. A conveyor belt having a core embedded in a cover rubber, wherein the cover rubber is made of vulcanized rubber having a rubber content of 30% by weight or more and a rebound resilience of 65% or more. . 2. The conveyor belt according to claim 1, wherein at least 50% by weight of the rubber is natural rubber. 3. The conveyor belt according to claim 1, wherein the rubber is natural rubber. 4. A cover rubber comprising a vulcanized rubber obtained by vulcanizing a rubber compound containing 15 to 200 parts by weight of calcium carbonate per 100 parts by weight of rubber.
The transport belt according to any one of the above. 5. A rubber cover rubber comprising 100 parts by weight of rubber, (a) carbon black having an average particle diameter of 55 nm or more, (b) carbon black having an average particle diameter of 30 nm or more and less than 55 nm, and (c) an average particle diameter of less than 30 nm. The transport belt according to any one of claims 1 to 4, comprising a vulcanized rubber obtained by vulcanizing a rubber compound containing at least any one of the following carbon blacks in a total amount of 5 parts by weight or less. 6. A transport belt having a core buried in cover rubber, wherein the cover rubber is made of vulcanized rubber having a rubber content of 50% by weight or more and a rebound resilience of 65% or more. For 100 parts by weight of rubber, a total of at least one of (a) carbon black having an average particle diameter of 55 nm or more, (b) carbon black having an average particle diameter of 30 nm or more and less than 55 nm, and (c) carbon black having an average particle diameter of less than 30 nm A transport belt, which is a vulcanized rubber obtained by vulcanizing a rubber compound containing the rubber compound in an amount of 5 to 50 parts by weight. 7. The transport belt according to claim 6, wherein at least 50% by weight of the rubber is natural rubber. 8. The conveyor belt according to claim 6, wherein the rubber is natural rubber. 9. The cover rubber according to claim 6, wherein the cover rubber comprises a vulcanized rubber obtained by vulcanizing a rubber compound containing 15 to 90 parts by weight of calcium carbonate with respect to 100 parts by weight of the rubber. Transport belt.