Heat resistant conveyor belt

Patent metadata

Field	Value
Publication number	US-10364100-B2
Application number	US-201615781154-A
Country	US
Kind code	B2
Filing date	Dec 9, 2016
Priority date	Dec 10, 2015
Publication date	Jul 30, 2019
Grant date	Jul 30, 2019

Abstract

Heavy duty conveyor belts (1) having excellent resistance to high temperatures. These conveyor belts (1) can be repeatedly exposed to temperatures of greater than 200° C. or even 250° C. without compromising the strength or reliability of the belt while providing a greatly extended service life. The conveyor belts (1) may also be manufactured in a commercially viable and cost effective manner. The conveyor belts (1) generally include a reinforcement layer (3), a carry cover layer (2) disposed above the reinforcement layer (3), a pulley cover layer (4) disposed beneath the reinforcement layer (3), and the carry cover layer (2) is comprised of a fluoroelastomer. In some aspects, the conveyor belts (1) have a carry cover layer (2) which includes an outer surface layer (6) containing a fluoroelastomer and an inner layer (7) based upon an EPM elastomer or an EPDM elastomer.

First claim

What is claimed is:

1. A conveyor belt comprising a reinforcement layer, a carry cover layer above the reinforcement layer, and a pulley cover layer beneath the reinforcement layer, wherein the carry cover layer is comprised of a fluoroelastomer;
wherein the fluoroelastomer has a fluorine content which is within the range of 64 weight percent to 71 weight percent; and,
wherein the fluoroelastomer has repeat units which are comprised of at least two perfluorinated monomers and at least one cure site monomer.

2. The conveyor belt as specified in claim 1 wherein the carry cover layer comprises an outer surface layer which is comprised of the fluoroelastomer, and an inner layer which is comprised of an EPM elastomer or an EPDM elastomer.

3. The conveyor belt as specified in claim 2 wherein the outer surface layer is from 0.5 mm to 4 mm thick.

4. The conveyor belt as specified in claim 2 wherein the outer surface layer is from 1 mm to 2 mm thick.

5. The conveyor belt as specified in claim 1 wherein the fluoroelastomer has repeat units which are comprised of a perfluoroolefin monomer, a perfluorovinyl ether monomer, and a cure site monomer.

6. The conveyor belt as specified in claim 5 wherein the perfluoroolefin monomer is selected from the group consisting of vinylidene fluoride, hexafluoropropylene, and tetrafluoroethylene.

7. The conveyor belt as specified in claim 6 wherein the perfluorovinyl ether monomer is selected from the group consisting of perfluoro(methyl vinyl) ether and perfluoro(propyl vinyl) ether repeat units.

8. The conveyor belt as specified in claim 7 wherein the cure site monomer is selected from the group consisting of nitrile-containing fluorinated olefin monomers, nitrile-containing fluorinated vinyl ether monomers, fluorinated olefin monomers, brominated α-olefin monomers, and iodinated α-olefin monomers.

9. The conveyor belt as specified in claim 5 wherein the perfluoroolefin monomer is present in the fluoroelastomer at a level which is within the range of 20 weight percent to 80 weight percent, wherein the perfluorovinyl ether monomer is present in the fluoroelastomer at a level which is within the range of 20 weight percent to 80 weight percent, and wherein the cure site monomer is present in the fluoroelastomer at a level which is within the range of 0.1 weight percent to 5 weight percent.

10. The conveyor belt as specified in claim 9 wherein the cure site monomer is present in the fluoroelastomer at a level which is within the range of 0.2 weight percent to 2 weight percent.

11. The conveyor belt as specified in claim 9 wherein the cure site monomer is present in the fluoroelastomer at a level which is within the range of 0.3 weight percent to 1 weight percent.

12. A conveyor belt comprising a reinforcement layer, a carry cover layer disposed above the reinforcement layer, and a pulley cover layer disposed beneath the reinforcement layer, wherein the carry cover layer comprises a fluoroelastomer, and wherein the conveyor belt can transport materials having a temperature in excess of 200° C.;
wherein the fluoroelastomer has a fluorine content which is within the range of 64 weight percent to 71 weight percent; and,
wherein the fluoroelastomer has repeat units which are comprised of at least two perfluorinated monomers and at least one cure site monomer.

13. The conveyor belt as specified in claim 12 wherein the carry cover layer comprises an outer surface layer which is comprised of the fluoroelastomer, and an inner layer.

14. The conveyor belt as specified in claim 13 wherein the outer surface layer is from 1 mm to 4 mm thick.

15. The conveyor belt as specified in claim 12 wherein the fluoroelastomer has a fluorine content which is within the range of 64 weight percent to 71 weight percent.

16. The conveyor belt as specified in claim 12 wherein the fluoroelastomer of the carry cover layer is cured with a peroxide curative system.

17. The conveyor belt as specified in claim 12 wherein the fluoroelastomer of the carry cover layer is co-cured to an inner layer which is comprised of an EPM elastomer, an EPDM elastomer, or combination thereof.

18. The conveyor belt as specified in claim 13 wherein the inner layer comprises an EPM elastomer, an EPDM elastomer or combination thereof, and wherein the EPM elastomer, the EPDM elastomer or the combination thereof comprise ethylidene norbornene in an amount of 2% to 7% by weight.

19. The conveyor belt as specified in claim 17 wherein the EPM elastomer, the EPDM elastomer or the combination thereof comprises ethylidene norbornene in an amount of 2% to 7% by weight.

20. The conveyor belt as specified in claim 17 wherein the inner layer is formed of the EPM elastomer, the EPDM elastomer or the combination thereof, having a minimum Mooney viscosity at 121 deg C. (small rotor) of less than 20.5 MU.

21. The conveyor belt as specified in claim 17 wherein the EPM elastomer, the EPDM elastomer or the combination thereof has a cure rate of less than 4 dNm/min (Moving Die Rheometer, 165 deg C., ASTM D5289).

22. The conveyor belt as specified in claim 17 wherein the inner layer comprises silica at a level of from 10 phr to 50 phr.

23. The conveyor belt as specified in claim 17 wherein the inner layer comprises oil at a level of from 0 phr to 50 phr.

24. A method of manufacturing a conveyor belt, the method comprising:
providing a reinforcement layer;
disposing a pulley cover layer beneath the reinforcement layer; and,
disposing a carry cover layer above the reinforcement layer;

wherein the carry cover layer comprises an outer surface layer which is comprised of the fluoroelastomer, and an inner layer, and wherein the conveyor belt can transport materials having a temperature in excess of 200° C.;
wherein the fluoroelastomer has a fluorine content which is within the range of 64 weight percent to 71 weight percent; and,
wherein the fluoroelastomer has repeat units which are comprised of at least two perfluorinated monomers and at least one cure site monomer.

Assignees

• Contitech Transportbandsysteme

Inventors

• Maguire David J
• Burrowes Thomas George
• Rong Guangzhuo
• Seibold Sebastian
• Yang Heng-Huey

Classifications

• B32B25/042

  of natural rubber or synthetic rubber · CPC title

• B32B2307/304

  Insulating · CPC title

• B32B2433/02

  Conveyor belts · CPC title

• B65G15/38

  with flame-resistant layers, e.g. of asbestos, glass · CPC title

• B32B25/14

  comprising {synthetic rubber copolymers (B32B25/18 and B32B25/20 take precedence)} · CPC title