Thermally insulated components for exhaust systems

Patent metadata

Field	Value
Publication number	US-10450936-B2
Application number	US-201214345535-A
Country	US
Kind code	B2
Filing date	Sep 21, 2012
Priority date	Sep 22, 2011
Publication date	Oct 22, 2019
Grant date	Oct 22, 2019

Abstract

A component of an exhaust system for an internal combustion engine. The component comprises an exhaust system structure ( 20 ) having an interior ( 22 ) through which exhaust gases flow and an exterior ( 21 ), and a thermal insulating wrap ( 10 ) for thermally insulating at least a portion of the exterior ( 21 ) of the exhaust system structure ( 20 ). The thermal insulating wrap ( 10 ) comprises an aqueous mixture comprising an inorganic binder and inorganic filler particles, and a fabric comprising inorganic fibers. The fabric is impregnated with the aqueous mixture so as to form a pliable binder wrap ( 11 ). The pliable binder wrap ( 11 ) is wound completely around at least a portion of the exhaust system structure ( 20 ). It can be desirable for the component to further comprise at least one thermal insulator comprising inorganic fibers, where the thermal insulator is disposed between the pliable binder wrap ( 11 ) and the exterior 21 of the exhaust system structure ( 20 ).

First claim

What is claimed is:

1. A method of thermally insulating a component of a system, where (a) a portion or all of the component exhibits or produces an external elevated temperature and the system needs to be thermally insulated to prevent or reduce the loss or transfer of heat from the component into the surrounding environment, (b) a portion or all of the component or something within the component is susceptible to being damaged by exposure to elevated temperatures, or (c) both (a) and (b), with the component comprising a system component structure, said method comprising:
providing a thermal insulating wrap suitable for thermally insulating at least a portion of the system component structure, with the thermal insulating wrap comprising: a mixture comprising an inorganic binder, inorganic filler particles, and water; and
a fabric comprising inorganic fibers, with the fabric being impregnated with the mixture so as to form a pliable binder wrap, wherein the fabric can be impregnated with the mixture before or after being wound around the system component structure;
wrapping the pliable binder wrap so as to be wound almost completely or at least once around at least a portion of the system component structure; and
drying the pliable binder wrap so as to be transformed into a rigid binder wrap wound almost completely or at least once around at least the portion of the system component structure.

2. The method of claim 1 , wherein during said wrapping, the pliable binder wrap forms an exposed exterior surface of the component.

3. The method according to claim 2 , wherein the inorganic filler particles comprise any particulate, when mixed with the inorganic binder in the presence of water, that causes a substantial portion of the inorganic binder to be retained in the fabric without forming a gel or otherwise coagulating such that the pliable binder wrap becomes a solid mass before the pliable binder wrap can be wound almost completely or at least once around the system component structure.

4. The method according to claim 2 , wherein the inorganic binder comprises colloidal particles and the inorganic filler particles comprise any particulate that retains a substantial portion of the inorganic binder in the fabric while not forming a gel or otherwise coagulating when mixed with the inorganic binder in the presence of water.

5. The method according to claim 2 , wherein the inorganic filler particles have a maximum size of up to about 100 microns.

6. The method according to claim 2 , wherein the fabric is in the form of a sheet and only one layer of the sheet is needed to cover the portion of the system component structure to be thermally insulated.

7. The method according to claim 2 , wherein the fabric is in the form of a strip that must be wound multiple times around the system component structure in order to cover the portion of the system component structure to be thermally insulated.

8. The method according to claim 2 , further providing a metallic plate or foil, wherein the thermal insulating wrap provided further comprises at least one thermal insulator comprising inorganic fibers, and each of the at least one thermal insulator and the metallic plate or foil is disposed within the thermal insulating wrap between layers of the pliable binder wrap, between the pliable binder wrap and the system component structure, between the pliable binder wrap and a thermal insulator, or any combination thereof.

9. The method according to claim 1 , wherein the thermal insulating wrap provided further comprises at least one thermal insulator comprising inorganic fibers, and the at least one thermal insulator is disposed between the pliable binder wrap and the system component structure during said wrapping.

10. The method according to claim 2 , wherein at least 2 layers of the pliable binder wrap are wound around the system component structure.

11. The method according to claim 1 , wherein the rigid binder wrap exhibits a minimum crush strength of at least about 40 N, with the rigid binder wrap being at most crushed while the overall integrity of the rigid binder wrap is preserved.

12. The method according to claim 1 , wherein the component is a component of an exhaust system for an internal combustion engine, the component structure is an exhaust system component structure, and the thermal insulating wrap does not delaminate for at least 1 year or 12,000 miles of normal operation of the component in the exhaust system of an internal combustion engine.

13. The method according to claim 1 , wherein the pliable binder wrap comprises in the range of from about 1% to about 35% inorganic binder particles, from about 5% to about 75% inorganic filler particles, and from about 25% to about 65% of the inorganic fibers of the fabric, with each percentage being on a dry weight basis.

14. The method according to claim 1 , wherein the thermal insulating wrap is provided in a kit that includes the pliable binder wrap wound into the form of a roll and disposed into a moisture barrier container, and said method further comprises removing the pliable binder wrap from the moisture barrier container, before said wrapping of the pliable binder wrap.

15. The method according to claim 1 , further comprising a method of making the thermal insulating wrap comprising:
forming a mixture comprising mixing water, inorganic binder particles and inorganic filler particles;
providing a fabric comprising inorganic fibers that can be wound almost completely or at least once around at least a portion of a system component structure; and
impregnating the fabric with the mixture so as to form a pliable binder wrap,
wherein the fabric is impregnated with the mixture before or after being wound almost completely or at least once around the system component structure, and the pliable binder wrap is suitable for being wound almost completely or at least once around at least a portion of the system component structure such that the pliable binder wrap forms an exposed exterior surface of the component.

16. The method according to claim 9 , wherein the at least one thermal insulator is a plurality of separate thermal insulators that are disposed between the pliable binder wrap and the system component structure.

17. The method according to claim 1 , wherein the fabric is a woven fabric, a knitted fabric or both.

Assignees

• 3M Innovative Properties Co

Inventors

• Dietz Peter T

Classifications

• F16L59/027

  Bands, cords, strips or the like for helically winding around a cylindrical object · CPC title

• F01N2510/02

  for thermal insulation · CPC title

• F01N2450/08

  Repairing the housing or pipe-joints · CPC title

• F01N2310/14

  Wire mesh fabric, woven glass cloth or the like · CPC title

• F01N13/148 Primary

  Multiple layers of insulating material · CPC title