Apparatus for a fire-rated duct

1. A duct assembly suitable for fire-rated applications, said duct assembly comprising:

a liner section having an inner surface and an outer surface and a first end and a second end, and said liner section being formed from a thin steel material;

a non-combustible layer, said non-combustible layer being attached to and surrounding the outer surface of said liner section;

a flange assembly for the first end of said liner section, said flange assembly being removably coupled to said first end;

another flange assembly for the second end of said liner section, said flange assembly being removably coupled to said second end;

at least one longitudinal member having a first end for connecting to said flange assembly and a second end for connecting to said other flange assembly, and having a surface for securing a portion of said non-combustible layer and said liner section;

a fire-resistant sealant applied to joints between said liner section and said flange assemblies to prevent the flow of air from the inner surface of said liner section to exterior of said duct assembly; and

wherein one or both of said flange assemblies are coupled to said liner section during fabrication at a factory.

2. The duct assembly as claimed in claim 1 , wherein one or both of said flange assemblies include a fastening mechanism for connecting one or more of said duct assemblies.

3. The duct assembly as claimed in claim 2 , wherein said non-combustible layer comprises a fire-resistant panel attached to said liner section by a plurality of fasteners.

4. The duct assembly as claimed in claim 3 , wherein said non-combustible layer comprises more than one rated fire-resistant panels.

5. A fire-rated duct assembly comprising:

an inner duct liner having a first end, a second end, an inner surface and an outer surface;

at least one fire-resistant panel, said at least one fire-resistant panel being attached to the outer surface of said inner duct liner using one or more fasteners;

a first end connector member and fasteners therefor, said fasteners coupling said end connector member to one end of said inner duct liner and said at least one fire-resistant panel;

a second end connector member and fasteners therefor, said fasteners coupling said second end connector member to said second end of said inner duct liner and said at least one fire-resistant panel;

a plurality of longitudinal connector members having a first end and fasteners therefor for connecting to said first end connector member and a second end and fasteners therefor for connecting to said second end connector member, and having a surface for securing a portion of said at least one fire-resistant panel and fasteners therefor;

wherein said connector members, said inner duct liner and said at least one fire-resistant panel are assembled at a factory so that said duct assembly is shipped as a unit.

6. The fire-rated duct assembly as claimed in claim 5 , wherein said connector members include a fastening mechanism for connecting one or more of said duct assemblies in the field.

7. The fire-rated duct assembly as claimed in claim 5 or 6 , wherein said fasteners for one of said connector members comprise removable fasteners for disconnecting and reconnecting said one connector member for said duct assembly so that said duct assembly is modifiable in a field installation.

8. The fire-rated duct assembly as claimed in claim 5 or 6 , wherein the fasteners for one of said connector members are able to be installed in the field and said one connector member is shipped separate from the duct assembly so that the duct assembly is able to be modified in the field.

9. A fire-rated duct assembly comprising:

a rectangular inner duct liner having a first end, a second end, an inner surface and an outer surface;

a plurality of fire-resistant panels, each of said fire-resistant panels being attached to one side of the outer surface of said rectangular inner duct liner using one or more fasteners;

a first flanged connector member and fasteners therefor, said fasteners coupling said first flanged connector member to one end of said rectangular inner duct liner and said fire-resistant panels;

second flanged connector member and fasteners therefor, said fasteners coupling said second flanged connector member to the second end of said rectangular inner duct liner and said fire-resistant panels;

a plurality of longitudinal connector members having a first end and fasteners therefor for connecting to said first flanged connector member and a second end and fasteners therefor for connecting to said second flanged connector member, and having a surface for securing a portion of said fire-resistant panels;

one of said flanged connector members including a fastening mechanism for connecting one or more of said duct assemblies at a field site;

a fire-resistant sealant applied to said inner duct liner and said fire-resistant panels to seal said inner duct liner from air flow exterior to the duct assembly; and

wherein said flanged connector members, said rectangular inner duct liner and said fire-resistant panels are assembled at a factory so that said duct assembly is shipped as a unit to the field site.

10. The fire-rated duct assembly as claimed in claim 9 , wherein said fasteners for one of said flange connector members comprise removable fasteners for disconnecting and reconnecting said one flange connector member for said duct assembly so that said duct assembly is modifiable at the field site.

11. The fire-rated duct assembly as claimed in claim 10 , wherein the fasteners for said one flanged connector member are able to be installed in the field and said one flange connector member is shipped separate from the duct assembly so that the duct assembly is able to be modified in the field.

12. The fire-rated duct assembly as claimed in claim 9 , wherein the fasteners for one of said flange connector members are able to be installed in the field and said one flange connector member is shipped separate from the duct assembly so that the duct assembly is able to be modified in the field.

13. A duct assembly for providing a fire-rated conduit, said duct assembly comprising:

an inner duct liner having a first end, a second end, an inner surface and an outer surface, and said inner duct liner being formed from a thin steel sheet;

at least one fire-resistant panel, said at least one fire-resistant panel being attached to the outer surface of said inner duct liner using one or more fasteners;

a first connector member and fasteners therefor, said fasteners coupling said connector member to one end of said inner duct liner and said at least one fire-resistant panel;

a second connector member and fasteners therefor, said fasteners coupling said second connector member to the second end of said inner duct liner and said at least one fire-resistant panel;

a plurality of longitudinal connector members having a first end and fasteners therefor for connecting to said first connector member and a second end and fasteners therefor for connecting to said second connector member, and having a surface for securing a portion of said fire-resistant panel;

wherein said connector members, said inner duct liner and said fire-resistant panels are formed into an assembly at a factory, said assembly being shipped as a unit; and

wherein said assembly forms a conduit section.

14. The duct assembly as claimed in claim 13 , wherein said conduit sections are coupled together to form a conduit for running electrical wires.

15. The duct assembly as claimed in claim 13 , wherein said conduit sections are coupled together to form a conduit for running plumbing.

16. The duct assembly as claimed in claim 13 , wherein said conduit sections are coupled together to form a conduit for smoke evacuation.