U.S. patent application number 10/856982 was filed with the patent office on 2004-12-09 for casing-free insulation blanket.
This patent application is currently assigned to 3M Innovative Properties Company. Invention is credited to Khieu, Sithya S., Pieper, Richard M., Tompkins, Thomas L..
Application Number | 20040247819 10/856982 |
Document ID | / |
Family ID | 33551672 |
Filed Date | 2004-12-09 |
United States Patent
Application |
20040247819 |
Kind Code |
A1 |
Khieu, Sithya S. ; et
al. |
December 9, 2004 |
Casing-free insulation blanket
Abstract
An insulation blanket comprises (a) substantially hydrophobic
insulation material; and (b) high temperature-resistant material;
with the proviso that the blanket is casing-free.
Inventors: |
Khieu, Sithya S.; (Eden
Prairie, MN) ; Pieper, Richard M.; (New Brighton,
MN) ; Tompkins, Thomas L.; (Woodbury, MN) |
Correspondence
Address: |
3M INNOVATIVE PROPERTIES COMPANY
PO BOX 33427
ST. PAUL
MN
55133-3427
US
|
Assignee: |
3M Innovative Properties
Company
|
Family ID: |
33551672 |
Appl. No.: |
10/856982 |
Filed: |
May 28, 2004 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60477080 |
Jun 9, 2003 |
|
|
|
Current U.S.
Class: |
428/74 ;
428/292.1; 442/164; 442/38 |
Current CPC
Class: |
B32B 33/00 20130101;
Y10T 442/164 20150401; Y10T 442/2861 20150401; B32B 37/20 20130101;
B32B 17/02 20130101; B32B 2307/102 20130101; B32B 2307/304
20130101; B32B 2307/306 20130101; Y10T 428/249924 20150401; Y10T
428/237 20150115; F16L 59/026 20130101; B32B 2307/73 20130101 |
Class at
Publication: |
428/074 ;
428/292.1; 442/038; 442/164 |
International
Class: |
D04H 003/00 |
Claims
We claim:
1. An insulation blanket comprising (a) substantially hydrophobic
insulation material; and (b) high temperature-resistant material;
with the proviso that said blanket is casing-free.
2. The blanket of claim 1 wherein said substantially hydrophobic
insulation material comprises at least one polymer.
3. The blanket of claim 2 wherein said polymer is a polyolefin.
4. The blanket of claim 1 wherein said substantially hydrophobic
insulation material is fibrous.
5. The blanket of claim 1 wherein said high temperature-resistant
material is a flame-resistant material.
6. The blanket of claim 1 wherein said high temperature-resistant
material is a material that is both flame propagation-resistant and
flame penetration-resistant, or that is burnthrough-resistant.
7. An insulation blanket comprising (a) fibrous, substantially
hydrophobic insulation material comprising polyolefin; and (b) a
material that is both flame propagation-resistant and flame
penetration-resistant, or that is burnthrough-resistant; with the
proviso that said blanket is casing-free.
8. An insulation blanket comprising (a) substantially hydrophobic
insulation material comprising at least one polymer; and (b) a
material that is both flame propagation-resistant and flame
penetration-resistant, or that is burnthrough-resistant; said
materials being encased within a protective covering.
9. A process for producing an insulation blanket, the process
comprising the step of continuously bringing together, optionally
in the presence of one or more intervening or adjacent materials,
at least one insulation material and at least one high
temperature-resistant material.
10. The process of claim 9 wherein said insulation material
comprises substantially hydrophobic insulation material.
11. The process of claim 9 wherein said insulation material
comprises at least one polymer.
12. The process of claim 10 wherein said substantially hydrophobic
insulation material comprises at least one polymer.
13. The process of claim 11 or claim 12 wherein said polymer is a
polyolefin.
14. The process of claim 9 or claim 10 wherein said insulation
material is fibrous.
15. The process of claim 9 wherein said high temperature-resistant
material is a flame-resistant material.
16. The process of claim 9 wherein said high temperature-resistant
material is a material that is both flame propagation-resistant and
flame penetration-resistant, or that is burnthrough-resistant.
17. A process for producing an insulation blanket, the process
comprising the step of continuously bringing together, optionally
in the presence of one or more intervening or adjacent materials,
at least one fibrous, substantially hydrophobic insulation material
comprising polyolefin and at least one material that is both flame
propagation-resistant and flame penetration-resistant, or that is
burnthrough-resistant.
18. An insulation blanket produced by the process of claim 9,
wherein said materials are in the form of layers that are
substantially coextensive.
19. The blanket of claim 18, wherein said insulation material is
polymeric.
20. The blanket of claim 19, wherein said polymeric insulation
material is fibrous.
21. An insulation blanket produced by the process of claim 17,
wherein said materials are in the form of layers that are
substantially coextensive.
22. A process for insulating a surface, the process comprising the
step of providing said surface with the insulation blanket of claim
1, claim 7, claim 8, claim 18, or claim 21.
Description
STATEMENT OF PRIORITY
[0001] This application claims the priority of U.S. Provisional
Application No. 60/477,080 filed Jun. 9, 2003, the contents of
which are hereby incorporated by reference.
FIELD
[0002] This invention relates to insulation blankets for use as
thermal and/or acoustic shielding in, for example, transportation
vehicles such as aircraft. In other aspects, this invention also
relates to processes for preparing the blankets, to blankets
produced thereby, and to insulation processes.
BACKGROUND
[0003] Blankets providing thermal and/or acoustic insulation are
used in aircraft and other vehicles to shield passengers from
engine and aerodynamic noise and from temperature extremes. One
problem with such blankets is moisture uptake. This problem is
particularly significant in aircraft, where weight increases due to
water entrapment in the blankets can be dramatic. Not only is
moisture uptake undesirable from an economical standpoint, but it
causes other problems as well. These problems include reduced
thermal and acoustic performance, reduced service life for the
blanket, and increased potential for corrosion on the aluminum skin
and framing of the aircraft.
[0004] Insulation blankets for aircraft are typically comprised of
a fibrous lofted insulation such as fiberglass batting encased
within a protective covering. The protective covering is typically
made from two pieces of light-weight, tear-resistant, reinforced
polymer film. Although the protective covering can facilitate
blanket installation and also serve to protect the insulation from
damage during the installation process, its primary purpose is to
prevent moisture from being taken up and retained by the insulation
during the service life of the blanket. The protective covering,
however, increases blanket cost and weight.
[0005] The labor-intensive method of blanket construction that is
typically used further increases cost. The method involves cutting
two separate pieces of polymer film to a size slightly larger than
that of the insulation to be contained, so as to form selvedges.
The two pieces of film are then sealed along the selvedges (for
example, by sewing, by application of adhesive, or by heat sealing)
to encase the insulation.
SUMMARY
[0006] Thus, we recognize that there is a need for insulation
blankets that exhibit relatively low moisture uptake, that are
relatively light in weight and low in cost, and that can be simply
and cost-effectively produced without the need for labor-intensive,
multiple process steps.
[0007] Briefly, in one aspect, this invention provides such an
insulation blanket, which comprises (a) substantially hydrophobic
insulation material; and (b) high temperature-resistant material;
with the proviso that the blanket is casing-free. The insulation
material preferably comprises polymer (more preferably, it
comprises polyolefin). Preferably, the insulation material is
fibrous. The high temperature-resistant material is preferably a
flame-resistant material (more preferably, a burnthrough-resistant
material).
[0008] It has been discovered that insulation blankets can function
effectively without the need for a protective covering or casing
when substantially hydrophobic insulation material is utilized in
their construction. For example, fibrous insulation made from
substantially hydrophobic polymer such as polypropylene exhibits
little moisture uptake and substantially maintains its thermal and
acoustic performance without the need for a casing. In spite of the
organic nature of such insulation material, the requisite thermal
insulation characteristics of the blanket can be achieved by the
addition of high temperature-resistant material (for example,
fiberglass paper or ceramic paper) to the blanket construction.
Surprisingly, by appropriate selection of the high-temperature
resistant material, the blanket can even be rendered
burnthrough-resistant.
[0009] Since the insulation blanket of the invention is casing- or
bag-free, it can be easily and cost-effectively manufactured by
continuously bringing together its component layers, without the
need for separate, labor-intensive cutting, assembling, and sealing
steps. The blanket can be made in the form of wide panels or webs
that are conformable to vehicle surfaces and that enable
installation with only a minimal number of seams, reducing the need
for taping to prevent flame propagation. Thus, the blanket meets
the need in the art for thermal/acoustic insulation blankets that
exhibit relatively low moisture uptake, that are relatively light
in weight and low in cost, and that can be simply and
cost-effectively produced and installed without the need for
labor-intensive, multiple process steps.
[0010] In other aspects, this invention also provides the
following:
[0011] an encased version of the insulation blanket (for ultimate
moisture exclusion yet burnthrough resistance) comprising (a)
substantially hydrophobic insulation material comprising at least
one polymer (preferably, polyolefin; more preferably,
polypropylene), and (b) burnthrough-resistant material, the
materials being encased within a protective covering;
[0012] a process for producing the insulation blankets of the
invention, the process comprising the step of continuously bringing
together, optionally in the presence of one or more intervening or
adjacent materials, at least one insulation material and at least
one high temperature-resistant material;
[0013] a blanket produced by the process, wherein the materials are
in the form of layers that are substantially coextensive; and
[0014] a process for insulating a surface, the process comprising
the step of providing the surface with an insulation blanket of the
invention.
DETAILED DESCRIPTION
[0015] Definitions
[0016] As used in this patent application:
[0017] "substantially hydrophobic" means having hydrophobicity
greater than or equal to that of untreated linear polyethylene
(M.sub.n=.infin.) (as evidenced by measurements of contact angle or
surface tension such as those compiled in Polymer Handbook, Fourth
Edition, edited by J. Brandrup, E. H. Immergut, and E. A. Grulke,
John Wiley & Sons, New York (1999));
[0018] "high temperature-resistant material" means a material that
does not melt, flow, decompose, or otherwise substantially change
shape at temperatures up to at least about 500.degree. C.;
[0019] "casing-free" in reference to an insulation blanket means
that the insulation material of the blanket is not encased in a
protective covering (that is, although the blanket can comprise
exterior protective layers, these protective layers are not
directly sealed to each other (that is, are not sealed to each
other in the absence of intervening insulation material) so as to
substantially fully enclose the insulation);
[0020] "substantially coextensive" in reference to the component
layers of an insulation blanket means that, if the blanket has
exterior protective layers, the exterior protective layers do not
extend beyond the insulation layer(s) of the blanket so as to form
selvedges for direct sealing of the exterior protective layers to
each other in the absence of intervening insulation layer(s);
[0021] "lofty" in reference to a material means a fluffy material
that, after application and removal of a compressive force,
substantially resumes its original shape;
[0022] "flame-resistant material" means a material that meets the
flammability requirements of the Federal Aviation Administration
set forth at 14 C.F.R. Part 25, Sections 25.853(a) and 25.855(d)
(which reference Part I of Appendix F to Part 25), the texts of
which are incorporated herein by reference;
[0023] "flame propagation-resistant material" means a material that
meets the flammability requirements of the Federal Aviation
Administration set forth at 14 C.F.R. Part 25, Section 25.856(a)
(which references Part VI of Appendix F to Part 25), the texts of
which are incorporated herein by reference;
[0024] "flame penetration-resistant material" means a material that
meets the flammability requirements of the Federal Aviation
Administration set forth at 14 C.F.R. Part 25, Section 25.856(b)
(which references Part VII of Appendix F to Part 25), the texts of
which are incorporated herein by reference; and
[0025] "burnthrough-resistant material" means a material that meets
the flammability requirements of the Federal Aviation
Administration set forth at 14 C.F.R. Part 25, Sections 25.853(a)
and 25.855(d) (which reference Part I of Appendix F to Part 25), as
well as those set forth at 14 C.F.R. Part 25, Sections 25.856(a)
(flame propagation)and 25.856(b) (flame penetration) (which
reference Parts VI and VII, respectively, of Appendix F to Part
25), the texts of which are incorporated herein by reference.
[0026] Substantially Hydrophobic Insulation Material
[0027] Insulation materials suitable for use in the insulation
blanket of the invention are those that are more hydrophobic than
untreated linear polyethylene, as evidenced by measured parameters
known to correlate with hydrophobicity (for example, contact angle
or surface tension measurements). Such materials include
substantially hydrophobic polymers such as polyolefins (for
example, polyethylene and polypropylene) and the like, and
substantially hydrophobic blends thereof with each other and/or
with other polymers. Other less hydrophobic materials can also be
utilized, provided that they are treated to increase their
hydrophobicity to greater than that of untreated linear
polyethylene. Such hydrophobicity treatments can involve, for
example, the use of silicones or fluorochemicals as topical
treatments or polymer melt additives. Substantially hydrophobic
polymers or other materials can also be treated, if desired, to
further enhance their hydrophobicity characteristics. Preferably,
the insulation material comprises or consists essentially of at
least one polymer (more preferably, it comprises or consists
essentially of at least one polyolefin; most preferably, it
comprises or consists essentially of polypropylene).
[0028] Blends of polypropylene and polyethylene terephthalate (PET)
can be used to prepare useful insulation material. Preferably, the
blends comprise at least about 50 percent polypropylene (more
preferably, at least about 55 percent; even more preferably, at
least about 65 percent; most preferably, at least about 80
percent). Lesser amounts of polypropylene can be utilized, however,
when hydrophobicity treatments are applied.
[0029] The insulation material can be in the form of fibrous
insulation, foam insulation, or combinations thereof, with lofty
fibrous insulation being preferred. Such materials can be
manufactured by known methods. Suitable fibrous materials include,
for example, the melt blown fibers comprising polypropylene that
are commercially available from 3M Company of St. Paul, Minn. under
the trade designation THINSULATE. Fibrous insulation can be
provided in the form of a lofty non-woven layer or mat in which the
fibers are entangled with or bonded to each other. Such mats can be
prepared according to conventional techniques such as melt blowing,
air laying, or carding. The mats can be made with thermobonding
fibers and exposed to heat to cause the thermobonding fibers to
soften and bind at least some of the fibers together.
[0030] An example of a useful lofty nonwoven mat is described in
U.S. Pat. No. 4,837,067 (Carey et al.), the description of which is
incorporated herein by reference. As described therein, the mat
consists of a combination of entangled staple fibers and bonding
staple fibers where the bonding fibers have, for example, a core of
polyethylene terephthalate surrounded by a sheath of an adhesive
polymer formed from isophthalate and terephthalate esters.
[0031] Other useful fibrous nonwoven webs are those that comprise a
collected mass of directly-formed fibers disposed within the web in
a C-shaped configuration, and crimped staple fibers dispersed
within the web to give the web loft and uniformity. Such
directly-formed fibers are fibers formed and collected as a web in
essentially one operation, for example, by extruding fibers from a
fiber-forming liquid (for example, molten or dissolved polymer,
glass, or the like) and collecting the extruded fibers as a web.
"C-shaped configuration" means that the fibers are assembled or
organized in the web so that, when the web is viewed in a vertical,
longitudinal cross-section, a representative individual
directly-formed fiber is seen to include a) a segment or segments
disposed within the web transversely to the faces of the web (this
segment(s) forms the vertical portion of the "C"), and b) other
segments (the arms of the "C"), which are connected to the
transverse segment(s), are substantially parallel to the opposite
faces of the web, and extend from the transverse segment in a
direction opposite from the "machine direction" of the web (the
direction in which the web moved during formation).
[0032] Other known insulation constructions can also be utilized
including, for example, the thermally insulating sheet material
described in U.S. Pat. No. 4,136,222 (Jonnes), the description of
which is incorporated herein by reference.
[0033] High Temperature-Resistant Material
[0034] Suitable high temperature-resistant materials for use in the
insulation blanket of the invention include ceramic papers (for
example, aluminosilicate ceramic fiber papers commercially
available as KAOWOOL Paper from Thermal Ceramics, Inc., Augusta,
Ga., and under the trade designation LYTHERM Paper from Lydall,
Inc. of Rochester, N.H., as well as a ceramic fiber paper
encapsulated in polyimide film available as 3M NEXTEL Flame Shield
AL-1 from 3M Company, St. Paul, Minn.), woven ceramic fibers (for
example, fabrics commercially available under the trade designation
NEXTEL 312 AF-10 Aerospace Fabric from 3M Company, St. Paul,
Minn.), woven fiberglass fibers (for example, fabrics commercially
available under the trade designation SILTEMP Silica Fabric Type
84CH from Ametek of Wilmington, Del.), ceramic non-woven scrims
(for example, scrims prepared from ceramic oxide fibers
commercially available under the trade designation NEXTEL 312
Ceramic Fibers from 3M Company, St. Paul, Minn.), and fiberglass
non-woven scrims. Such materials can be manufactured by known
methods. Suitable high temperature-resistant materials include
those described in U.S. Pat. No. 6,670,291 (Tompkins et al.), the
description of which is incorporated herein by reference.
[0035] Preferred high temperature-resistant materials are
flame-resistant materials (for example, aluminosilicate ceramic
fiber papers and S-glass paper). More preferred high
temperature-resistant materials are both flame
propagation-resistant and flame penetration-resistant. Most
preferred high temperature-resistant materials are burnthrough
resistant materials (for example, ceramic papers such as 3M NEXTEL
Flame Stopping Dot Paper, available from 3M Company, St. Paul,
Minn., and vermiculite-coated ceramic paper available as 3M NEXTEL
Flame Stopping Coated Paper from 3M Company, as well as NOMEX Type
418 Paper available from DuPont, Richmond, Va.).
[0036] Additional Materials or Layers The insulation blanket of the
invention can comprise one or more layers of substantially
hydrophobic insulation material and one or more layers of
high-temperature resistant material. In addition, other materials
and layers conventionally found in insulation blankets can be
included. For example, the blanket can further comprise one or more
adhesive compositions or films, one or more scrims (for example,
woven polymeric fabric), one or more water repellent coatings, one
or more intumescent additives or coatings, and one or more polymer
films (which can optionally be metallized), as well as flame
retardants, antistatic agents, anti-mildew agents, and the like.
When casing-free blankets are desired, however, the additional
materials and/or layers are preferably selected so as to not
significantly increase the moisture uptake and retention
characteristics of the blanket.
[0037] Production, Installation, and Use of Insulation Blanket
[0038] The insulation blankets of the invention can be prepared by
known methods such as those described in U.S. Pat. No. 5,624,726
(Sanocki et al.), the description of which is incorporated herein
by reference. Preferably, the blankets are prepared by a continuous
process that is simpler and more cost-effective than prior methods.
This process comprises the step of continuously bringing together,
optionally in the presence of one or more intervening or adjacent
materials (as described in the previous section), at least one
insulation material (which can be of any type, but which is
preferably substantially hydrophobic) and at least one high
temperature-resistant material. In a preferred embodiment of the
process, fibrous insulation material can be continuously deposited
on a moving web of high temperature-resistant material, for
example, by melt blowing, air laying, or carding.
[0039] Unlike conventional insulation blankets (which rely upon
selvedges for blanket assembly and casing), blankets produced by
the continuous process of the invention can, if desired, be
constructed so as to have substantially coextensive layers. The
preferred use of polymeric insulation material (more preferably,
fibrous polymeric insulation material) provides blankets that are
cold-sealable by cutting. If desired, the blankets can be provided
with check valves, although these are not necessary due to the
blankets' casing-free construction. Other optional features include
holes (to aid in blanket installation) and non-encasing external
protective layers.
[0040] The blankets of the invention are useful in a variety of
applications requiring thermal and/or acoustic insulation (for
example, in aircraft, automobiles, and other vehicles) and can be
installed using known methods. The blankets can be particularly
useful as fire barriers.
EXAMPLES
[0041] Objects and advantages of this invention are further
illustrated by the following examples, but the particular materials
and amounts thereof recited in these examples, as well as other
conditions and details, should not be construed to unduly limit
this invention.
[0042] Flammability Requirements of the Federal Aviation
Administration
[0043] 14 C.F.R. Section 25.853 Compartment Interiors.
[0044] For each compartment occupied by the crew or passengers, the
following apply:
[0045] (a) Materials (including finishes or decorative surfaces
applied to the materials) must meet the applicable test criteria
prescribed in part I of appendix F of this part, or other approved
equivalent methods, regardless of the passenger capacity of the
airplane.
[0046] (b) [Reserved]
[0047] (c) In addition to meeting the requirements of paragraph (a)
of this section, seat cushions, except those on flight crewmember
seats, must meet the test requirements of part II of appendix F of
this part, or other equivalent methods, regardless of the passenger
capacity of the airplane.
[0048] (d) Except as provided in paragraph (e) of this section, the
following interior components of airplanes with passenger
capacities of 20 or more must also meet the test requirements of
parts IV and V of appendix F of this part, or other approved
equivalent method, in addition to the flammability requirements
prescribed in paragraph (a) of this section:
[0049] (1) Interior ceiling and wall panels, other than lighting
lenses and windows;
[0050] (2) Partitions, other than transparent panels needed to
enhance cabin safety;
[0051] (3) Galley structure, including exposed surfaces of stowed
carts and standard containers and the cavity walls that are exposed
when a full complement of such carts or containers is not carried;
and
[0052] (4) Large cabinets and cabin stowage compartments, other
than underseat stowage compartments for stowing small items such as
magazines and maps.
[0053] (e) The interiors of compartments, such as pilot
compartments, galleys, lavatories, crew rest quarters, cabinets and
stowage compartments, need not meet the standards of paragraph (d)
of this section, provided the interiors of such compartments are
isolated from the main passenger cabin by doors or equivalent means
that would normally be closed during an emergency landing
condition.
[0054] (f) Smoking is not to be allowed in lavatories. If smoking
is to be allowed in any other compartment occupied by the crew or
passengers, an adequate number of self-contained, removable
ashtrays must be provided for all seated occupants.
[0055] (g) Regardless of whether smoking is allowed in any other
part of the airplane, lavatories must have self-contained,
removable ashtrays located conspicuously on or near the entry side
of each lavatory door, except that one ashtray may serve more than
one lavatory door if the ashtray can be seen readily from the cabin
side of each lavatory served.
[0056] (h) Each receptacle used for the disposal of flammable waste
material must be fully enclosed, constructed of at least fire
resistant materials, and must contain fires likely to occur in it
under normal use. The capability of the receptacle to contain those
fires under all probable conditions of wear, misalignment, and
ventilation expected in service must be demonstrated by test.
[0057] [Arndt. 25-83, 60 FR 6623, Feb. 2, 1995]
[0058] 14 C.F.R. Section 25.855 Cargo or Baggage Compartments
[0059] For each cargo and baggage compartment not occupied by crew
or passengers, the following apply:
[0060] (a) The compartment must meet one of the class requirements
of .sctn.25.857.
[0061] (b) Class B through Class E cargo or baggage compartments,
as defined in .sctn.25.857, must have a liner, and the liner must
be separate from (but may be attached to) the airplane
structure.
[0062] (c) Ceiling and sidewall liner panels of Class C
compartments must meet the test requirements of part III of
appendix F of this part or other approved equivalent methods.
[0063] (d) All other materials used in the construction of the
cargo or baggage compartment must meet the applicable test criteria
prescribed in part I of appendix F of this part or other approved
equivalent methods.
[0064] (e) No compartment may contain any controls, wiring, lines,
equipment, or accessories whose damage or failure would affect safe
operation, unless those items are protected so that--
[0065] (1) They cannot be damaged by the movement of cargo in the
compartment, and
[0066] (2) Their breakage or failure will not create a fire
hazard.
[0067] (f) There must be means to prevent cargo or baggage from
interfering with the functioning of the fire protective features of
the compartment.
[0068] (g) Sources of heat within the compartment must be shielded
and insulated to prevent igniting the cargo or baggage.
[0069] (h) Flight tests must be conducted to show compliance with
the provisions of .sctn.25.857 concerning--
[0070] (1) Compartment accessibility,
[0071] (2) The entries of hazardous quantities of smoke or
extinguishing agent into compartments occupied by the crew or
passengers, and
[0072] (3) The dissipation of the extinguishing agent in Class C
compartments.
[0073] (i) During the above tests, it must be shown that no
inadvertent operation of smoke or fire detectors in any compartment
would occur as a result of fire contained in any other compartment,
either during or after extinguishment, unless the extinguishing
system floods each such compartment simultaneously.
[0074] [Amdt. 25-72, 55 FR 29784, Jul. 20, 1990, as amended by
Amdt. 25-93, 63 FR 8048, Feb.17, 1998
[0075] 14 C.F.R. Section 25.856 Thermal/Acoustic Insulation
Materials.
[0076] (a) Thermal/acoustic insulation material installed in the
fuselage must meet the flame propagation test requirements of part
VI of Appendix F to this part, or other approved equivalent test
requirements. This requirement does not apply to "small parts," as
defined in part I of Appendix F of this part.
[0077] (b) For airplanes with a passenger capacity of 20 or
greater, thermal/acoustic insulation materials (including the means
of fastening the materials to the fuselage) installed in the lower
half of the airplane fuselage must meet the flame penetration
resistance test requirements of part VII of Appendix F to this
part, or other approved equivalent test requirements. This
requirement does not apply to thermal/acoustic insulation
installations that the FAA finds would not contribute to fire
penetration resistance.
[0078] [Amdt. 25-111, 68 FR 45059, Jul. 31, 2003]
[0079] Appendix F to Part 25
[0080] Part I--Test Criteria and Procedures for Showing Compliance
with Section 25.853 or Section 25.855.
[0081] (a) Material test criteria--(1) Interior compartments
occupied by crew or passengers. (i) Interior ceiling panels,
interior wall panels, partitions, galley structure, large cabinet
walls, structural flooring, and materials used in the construction
of stowage compartments (other than underseat stowage compartments
and compartments for stowing small items such as magazines and
maps) must be self-extinguishing when tested vertically in
accordance with the applicable portions of part I of this appendix.
The average burn length may not exceed 6 inches and the average
flame time after removal of the flame source may not exceed 15
seconds. Drippings from the test specimen may not continue to flame
for more than an average of 3 seconds after falling.
[0082] (ii) Floor covering, textiles (including draperies and
upholstery), seat cushions, padding, decorative and nondecorative
coated fabrics, leather, trays and galley furnishings, electrical
conduit, air ducting, joint and edge covering, liners of Class B
and E cargo or baggage compartments, floor panels of Class B, C, D,
or E cargo or baggage compartments, cargo covers and
transparencies, molded and thermoformed parts, air ducting joints,
and trim strips (decorative and chafing), that are constructed of
materials not covered in subparagraph (iv) below, must be
self-extinguishing when tested vertically in accordance with the
applicable portions of part I of this appendix or other approved
equivalent means. The average burn length may not exceed 8 inches,
and the average flame time after removal of the flame source may
not exceed 15 seconds. Drippings from the test specimen may not
continue to flame for more than an average of 5 seconds after
falling.
[0083] (iii) Motion picture film must be safety film meeting the
Standard Specifications for Safety Photographic Film PHI.25
(available from the American National Standards Institute, 1430
Broadway, New York, N.Y. 10018). If the film travels through ducts,
the ducts must meet the requirements of subparagraph (ii) of this
paragraph.
[0084] (iv) Clear plastic windows and signs, parts constructed in
whole or in part of elastomeric materials, edge lighted instrument
assemblies consisting of two or more instruments in a common
housing, seat belts, shoulder harnesses, and cargo and baggage
tiedown equipment, including containers, bins, pallets, etc., used
in passenger or crew compartments, may not have an average burn
rate greater than 2.5 inches per minute when tested horizontally in
accordance with the applicable portions of this appendix.
[0085] (v) Except for small parts (such as knobs, handles, rollers,
fasteners, clips, grommets, rub strips, pulleys, and small
electrical parts) that would not contribute significantly to the
propagation of a fire and for electrical wire and cable insulation,
materials in items not specified in paragraphs (a)(1)(i), (ii),
(iii), or (iv) of part I of this appendix may not have a burn rate
greater than 4.0 inches per minute when tested horizontally in
accordance with the applicable portions of this appendix.
[0086] (2) Cargo and baggage compartments not occupied by crew or
passengers.
[0087] (i) [Reserved]
[0088] (ii) A cargo or baggage compartment defined in .sctn.25.857
as Class B or E must have a liner constructed of materials that
meet the requirements of paragraph (a)(1)(ii) of part I of this
appendix and separated from the airplane structure (except for
attachments). In addition, such liners must be subjected to the 45
degree angle test. The flame may not penetrate (pass through) the
material during application of the flame or subsequent to its
removal. The average flame time after removal of the flame source
may not exceed 15 seconds, and the average glow time may not exceed
10 seconds.
[0089] (iii) A cargo or baggage compartment defined in .sctn.25.857
as Class B, C, D, or E must have floor panels constructed of
materials which meet the requirements of paragraph (a)(1)(ii) of
part I of this appendix and which are separated from the airplane
structure (except for attachments). Such panels must be subjected
to the 45 degree angle test. The flame may not penetrate (pass
through) the material during application of the flame or subsequent
to its removal. The average flame time after removal of the flame
source may not exceed 15 seconds, and the average glow time may not
exceed 10 seconds.
[0090] (iv) Insulation blankets and covers used to protect cargo
must be constructed of materials that meet the requirements of
paragraph (a)(1)(ii) of part I of this appendix. Tiedown equipment
(including containers, bins, and pallets) used in each cargo and
baggage compartment must be constructed of materials that meet the
requirements of paragraph (a)(1)(v) of part I of this appendix.
[0091] (3) Electrical system components. Insulation on electrical
wire or cable installed in any area of the fuselage must be
self-extinguishing when subjected to the 60 degree test specified
in part I of this appendix. The average burn length may not exceed
3 inches, and the average flame time after removal of the flame
source may not exceed 30 seconds. Drippings from the test specimen
may not continue to flame for more than an average of 3 seconds
after falling.
[0092] (b) Test Procedures--(1) Conditioning. Specimens must be
conditioned to 70.+-.5 F., and at 50 percent .+-.5 percent relative
humidity until moisture equilibrium is reached or for 24 hours.
Each specimen must remain in the conditioning environment until it
is subjected to the flame.
[0093] (2) Specimen configuration. Except for small parts and
electrical wire and cable insulation, materials must be tested
either as section cut from a fabricated part as installed in the
airplane or as a specimen simulating a cut section, such as a
specimen cut from a flat sheet of the material or a model of the
fabricated part. The specimen may be cut from any location in a
fabricated part; however, fabricated units, such as sandwich
panels, may not be separated for test. Except as noted below, the
specimen thickness must be no thicker than the minimum thickness to
be qualified for use in the airplane. Test specimens of thick foam
parts, such as seat cushions, must be 1/2-inch in thickness. Test
specimens of materials that must meet the requirements of paragraph
(a)(1)(v) of part I of this appendix must be no more than 1/8-inch
in thickness. Electrical wire and cable specimens must be the same
size as used in the airplane. In the case of fabrics, both the warp
and fill direction of the weave must be tested to determine the
most critical flammability condition. Specimens must be mounted in
a metal frame so that the two long edges and the upper edge are
held securely during the vertical test prescribed in subparagraph
(4) of this paragraph and the two long edges and the edge away from
the flame are held securely during the horizontal test prescribed
in subparagraph (5) of this paragraph. The exposed area of the
specimen must be at least 2 inches wide and 12 inches long, unless
the actual size used in the airplane is smaller. The edge to which
the burner flame is applied must not consist of the finished or
protected edge of the specimen but must be representative of the
actual cross-section of the material or part as installed in the
airplane. The specimen must be mounted in a metal frame so that all
four edges are held securely and the exposed area of the specimen
is at least 8 inches by 8 inches during the 45.degree. test
prescribed in subparagraph (6) of this paragraph.
[0094] (3) Apparatus. Except as provided in subparagraph (7) of
this paragraph, tests must be conducted in a draft-free cabinet in
accordance with Federal Test Method Standard 191 Model 5903
(revised Method 5902) for the vertical test, or Method 5906 for
horizontal test (available from the General Services
Administration, Business Service Center, Region 3, Seventh & D
Streets SW., Washington, DC 20407). Specimens which are too large
for the cabinet must be tested in similar draft-free
conditions.
[0095] (4) Vertical test. A minimum of three specimens must be
tested and results averaged. For fabrics, the direction of weave
corresponding to the most critical flammability conditions must be
parallel to the longest dimension. Each specimen must be supported
vertically. The specimen must be exposed to a Bunsen or Tirrill
burner with a nominal 3/8-inch I.D. tube adjusted to give a flame
of 11/2 inches in height. The minimum flame temperature measured by
a calibrated thermocouple pyrometer in the center of the flame must
be 1550.degree. F. The lower edge of the specimen must be 3/4-inch
above the top edge of the burner. The flame must be applied to the
center line of the lower edge of the specimen. For materials
covered by paragraph (a)(1)(i) of part I of this appendix, the
flame must be applied for 60 seconds and then removed. For
materials covered by paragraph (a)(1)(ii) of part I of this
appendix, the flame must be applied for 12 seconds and then
removed. Flame time, burn length, and flaming time of drippings, if
any, may be recorded. The burn length determined in accordance with
subparagraph (7) of this paragraph must be measured to the nearest
tenth of an inch.
[0096] (5) Horizontal test. A minimum of three specimens must be
tested and the results averaged. Each specimen must be supported
horizontally. The exposed surface, when installed in the aircraft,
must be face down for the test. The specimen must be exposed to a
Bunsen or Tirrill burner with a nominal 3/8-inch I.D. tube adjusted
to give a flame of 11/2 inches in height. The minimum flame
temperature measured by a calibrated thermocouple pyrometer in the
center of the flame must be 1550.degree. F. The specimen must be
positioned so that the edge being tested is centered 3/4-inch above
the top of the burner. The flame must be applied for 15 seconds and
then removed. A minimum of 10 inches of specimen must be used for
timing purposes, approximately 11/2 inches must burn before the
burning front reaches the timing zone, and the average burn rate
must be recorded.
[0097] (6) Forty-five degree test. A minimum of three specimens
must be tested and the results averaged. The specimens must be
supported at an angle of 45.degree. to a horizontal surface. The
exposed surface when installed in the aircraft must be face down
for the test. The specimens must be exposed to a Bunsen or Tirrill
burner with a nominal 3/8-inch I.D. tube adjusted to give a flame
of 11/2 inches in height. The minimum flame temperature measured by
a calibrated thermocouple pyrometer in the center of the flame must
be 1550.degree. F. Suitable precautions must be taken to avoid
drafts. The flame must be applied for 30 seconds with one-third
contacting the material at the center of the specimen and then
removed. Flame time, glow time, and whether the flame penetrates
(passes through) the specimen must be recorded.
[0098] (7) Sixty degree test. A minimum of three specimens of each
wire specification (make and size) must be tested. The specimen of
wire or cable (including insulation) must be placed at an angle of
60.degree. with the horizontal in the cabinet specified in
subparagraph (3) of this paragraph with the cabinet door open
during the test, or must be placed within a chamber approximately 2
feet high by 1 foot by 1 foot, open at the top and at one vertical
side (front), and which allows sufficient flow of air for complete
combustion, but which is free from drafts. The specimen must be
parallel to and approximately 6 inches from the front of the
chamber. The lower end of the specimen must be held rigidly
clamped. The upper end of the specimen must pass over a pulley or
rod and must have an appropriate weight attached to it so that the
specimen is held tautly throughout the flammability test. The test
specimen span between lower clamp and upper pulley or rod must be
24 inches and must be marked 8 inches from the lower end to
indicate the central point for flame application. A flame from a
Bunsen or Tirrill burner must be applied for 30 seconds at the test
mark. The burner must be mounted underneath the test mark on the
specimen, perpendicular to the specimen and at an angle of
30.degree. to the vertical plane of the specimen. The burner must
have a nominal bore of 3/8-inch and be adjusted to provide a 3-inch
high flame with an inner cone approximately one-third of the flame
height. The minimum temperature of the hottest portion of the
flame, as measured with a calibrated thermocouple pyrometer, may
not be less than 1750.degree. F. The burner must be positioned so
that the hottest portion of the flame is applied to the test mark
on the wire. Flame time, burn length, and flaming time of
drippings, if any, must be recorded. The burn length determined in
accordance with paragraph (8) of this paragraph must be measured to
the nearest tenth of an inch. Breaking of the wire specimens is not
considered a failure.
[0099] (8) Burn length. Burn length is the distance from the
original edge to the farthest evidence of damage to the test
specimen due to flame impingement, including areas of partial or
complete consumption, charring, or embrittlement, but not including
areas sooted, stained, warped, or discolored, nor areas where
material has shrunk or melted away from the heat source.
[0100] Part VI--Test Method to Determine the Flammability and Flame
Propagation Characteristics of Thermal/Acoustic Insulation
Materials
[0101] Use this test method to evaluate the flammability and flame
propagation characteristics of thermal/acoustic insulation when
exposed to both a radiant heat source and a flame.
[0102] (a) Definitions.
[0103] "Flame propagation" means the furthest distance of the
propagation of visible flame towards the far end of the test
specimen, measured from the midpoint of the ignition source flame.
Measure this distance after initially applying the ignition source
and before all flame on the test specimen is extinguished. The
measurement is not a determination of burn length made after the
test.
[0104] "Radiant heat source" means an electric or air propane
panel.
[0105] "Thermal/acoustic insulation" means a material or system of
materials used to provide thermal and/or acoustic protection.
Examples include fiberglass or other batting material encapsulated
by a film covering and foams.
[0106] "Zero point" means the point of application of the pilot
burner to the test specimen.
[0107] (b) Test Apparatus.
[0108] (1) Radiant panel test chamber. Conduct tests in a radiant
panel test chamber. Place the test chamber under an exhaust hood to
facilitate clearing the chamber of smoke after each test. The
radiant panel test chamber must be an enclosure 55 inches (1397 mm)
long by 19.5 (495 mm) deep by 28 (710 mm) to 30 inches (maximum)
(762 mm) above the test specimen. Insulate the sides, ends, and top
with a fibrous ceramic insulation, such as Kaowool M.TM. board. On
the front side, provide a 52 by 12-inch (1321 by 305 mm)
draft-free, high-temperature, glass window for viewing the sample
during testing. Place a door below the window to provide access to
the movable specimen platform holder. The bottom of the test
chamber must be a sliding steel platform that has provision for
securing the test specimen holder in a fixed and level position.
The chamber must have an internal chimney with exterior dimensions
of 5.1 inches (129 mm) wide, by 16.2 inches (411 mm) deep by 13
inches (330 mm) high at the opposite end of the chamber from the
radiant energy source. The interior dimensions must be 4.5 inches
(114 mm) wide by 15.6 inches (395 mm) deep. The chimney must extend
to the top of the chamber.
[0109] (2) Radiant heat source. Mount the radiant heat energy
source in a cast iron frame or equivalent. An electric panel must
have six, 3-inch wide emitter strips. The emitter strips must be
perpendicular to the length of the panel. The panel must have a
radiation surface of 127/8 by 181/2 inches (327 by 470 mm). The
panel must be capable of operating at temperatures up to
1300.degree. F. (704.degree. C.). An air propane panel must be made
of a porous refractory material and have a radiation surface of 12
by 18 inches (305 by 457 mm). The panel must be capable of
operating at temperatures up to 1,500.degree. F. (816.degree.
C.).
[0110] i) Electric radiant panel. The radiant panel must be 3-phase
and operate at 208 volts. A single-phase, 240 volt panel is also
acceptable. Use a solid-state power controller and
microprocessor-based controller to set the electric panel operating
parameters.
[0111] (ii) Gas radiant panel. Use propane (liquid petroleum
gas--2.1 UN 1075) for the radiant panel fuel. The panel fuel system
must consist of a venturi-type aspirator for mixing gas and air at
approximately atmospheric pressure. Provide suitable
instrumentation for monitoring and controlling the flow of fuel and
air to the panel. Include an air flow gauge, an air flow regulator,
and a gas pressure gauge.
[0112] (iii) Radiant panel placement. Mount the panel in the
chamber at 30.degree. to the horizontal specimen plane, and 71/2
inches above the zero point of the specimen.
[0113] (3) Specimen holding system.
[0114] (i) The sliding platform serves as the housing for test
specimen placement. Brackets may be attached (via wing nuts) to the
top lip of the platform in order to accommodate various thicknesses
of test specimens. Place the test specimens on a sheet of Kaowool
M.TM. board or 1260 Standard Board (manufactured by Thermal
Ceramics and available in Europe), or equivalent, either resting on
the bottom lip of the sliding platform or on the base of the
brackets. It may be necessary to use multiple sheets of material
based on the thickness of the test specimen (to meet the sample
height requirement). Typically, these non-combustible sheets of
material are available in 1/4 inch (6 mm) thicknesses. A sliding
platform that is deeper than a 2-inch (50.8 mm) platform is
acceptable as long as the sample height requirement is met.
[0115] (ii) Attach a 1/2 inch (13 mm) piece of Kaowool M.TM. board
or other high temperature material measuring 411/2 by 81/4 inches
(1054 by 210 mm) to the back of the platform. This board serves as
a heat retainer and protects the test specimen from excessive
preheating. The height of this board must not impede the sliding
platform movement (in and out of the test chamber). If the platform
has been fabricated such that the back side of the platform is high
enough to prevent excess preheating of the specimen when the
sliding platform is out, a retainer board is not necessary.
[0116] (iii) Place the test specimen horizontally on the
non-combustible board(s). Place a steel retaining/securing frame
fabricated of mild steel, having a thickness of 1/8 inch (3.2 mm)
and overall dimensions of 23 by 131/8 inches (584 by 333 mm) with a
specimen opening of 19 by 103/4 inches (483 by 273 mm) over the
test specimen. The front, back, and right portions of the top
flange of the frame must rest on the top of the sliding platform,
and the bottom flanges must pinch all 4 sides of the test specimen.
The right bottom flange must be flush with the sliding
platform.
[0117] (4) Pilot Burner. The pilot burner used to ignite the
specimen must be a Bernzomatic.TM. commercial propane venturi torch
with an axially symmetric burner tip and a propane supply tube with
an orifice diameter of 0.006 inches (0.15 mm). The length of the
burner tube must be 27/8 inches (71 mm). The propane flow must be
adjusted via gas pressure through an in-line regulator to produce a
blue inner cone length of 3/4 inch (19 mm). A 3/4 inch (19 mm)
guide (such as a thin strip of metal) may be soldered to the top of
the burner to aid in setting the flame height. The overall flame
length must be approximately 5 inches long (127 mm). Provide a way
to move the burner out of the ignition position so that the flame
is horizontal and at least 2 inches (50 mm) above the specimen
plane.
[0118] (5) Thermocouples. Install a 24 American Wire Gauge (AWG)
Type K (Chromel-Alumel) thermocouple in the test chamber for
temperature monitoring. Insert it into the chamber through a small
hole drilled through the back of the chamber. Place the
thermocouple so that it extends 11 inches (279 mm) out from the
back of the chamber wall, 111/2 inches (292 mm) from the right side
of the chamber wall, and is 2 inches (51 mm) below the radiant
panel. The use of other thermocouples is optional.
[0119] (6) Calorimeter. The calorimeter must be a one-inch
cylindrical water-cooled, total heat flux density, foil type Gardon
Gage that has a range of 0 to 5 BTU/ft.sup.2-second (0 to 5.7
Watts/cm.sup.2).
[0120] (7) Calorimeter calibration specification and procedure.
[0121] (i) Calorimeter specification.
[0122] (A) Foil diameter must be 0.25.+-.0.005 inches (6.35.+-.0.13
mm).
[0123] (B) Foil thickness must be 0.0005.+-.0.0001 inches
(0.013.+-.0.0025 mm).
[0124] (C) Foil material must be thermocouple grade Constantan.
[0125] (D) Temperature measurement must be a Copper Constantan
thermocouple.
[0126] (E) The copper center wire diameter must be 0.0005 inches
(0.013 mm).
[0127] (F) The entire face of the calorimeter must be lightly
coated with "Black Velvet" paint having an emissivity of 96 or
greater.
[0128] (ii) Calorimeter calibration.
[0129] (A) The calibration method must be by comparison to a like
standardized transducer.
[0130] (B) The standardized transducer must meet the specifications
given in paragraph VI(b)(6) of this appendix.
[0131] (C) Calibrate the standard transducer against a primary
standard traceable to the National Institute of Standards and
Technology (NIST).
[0132] (D) The method of transfer must be a heated graphite
plate.
[0133] (E) The graphite plate must be electrically heated, have a
clear surface area on each side of the plate of at least 2 by 2
inches (51 by 51 mm), and be 1/8 inch .+-.{fraction (1/16)} inch
thick (3.2.+-.1.6 mm).
[0134] (F) Center the 2 transducers on opposite sides of the plates
at equal distances from the plate.
[0135] (G) The distance of the calorimeter to the plate must be no
less than 0.0625 inches (1.6 mm), nor greater than 0.375 inches
(9.5 mm).
[0136] (H) The range used in calibration must be at least 0-3.5
BTUs/ft.sup.2 second (0-3.9 Watts/cm.sup.2 ) and no greater than
0-5.7 BTUs/ft.sup.2 second (0-6.4 Watts/cm.sup.2).
[0137] (I) The recording device used must record the 2 transducers
simultaneously or at least within {fraction (1/10)} of each
other.
[0138] (8) Calorimeter fixture. With the sliding platform pulled
out of the chamber, install the calorimeter holding frame and place
a sheet of non-combustible material in the bottom of the sliding
platform adjacent to the holding frame. This will prevent heat
losses during calibration. The frame must be 131/8 inches (333 mm)
deep (front to back) by 8 inches (203 mm) wide and must rest on the
top of the sliding platform. It must be fabricated of 1/8 inch (3.2
mm) flat stock steel and have an opening that accommodates a 1/2
inch (12.7 mm) thick piece of refractory board, which is level with
the top of the sliding platform. The board must have three 1-inch
(25.4 mm) diameter holes drilled through the board for calorimeter
insertion. The distance to the radiant panel surface from the
centerline of the first hole ("zero" position) must be 71/2.+-.1/8
inches (191.+-.3 mm). The distance between the centerline of the
first hole to the centerline of the second hole must be 2 inches
(51 mm). It must also be the same distance from the centerline of
the second hole to the centerline of the third hole. A calorimeter
holding frame that differs in construction is acceptable as long as
the height from the centerline of the first hole to the radiant
panel and the distance between holes is the same as described in
this paragraph.
[0139] (9) Instrumentation. Provide a calibrated recording device
with an appropriate range or a computerized data acquisition system
to measure and record the outputs of the calorimeter and the
thermocouple. The data acquisition system must be capable of
recording the calorimeter output every second during
calibration.
[0140] (10) Timing device. Provide a stopwatch or other device,
accurate to .+-.1 second/hour, to measure the time of application
of the pilot burner flame.
[0141] (c) Test Specimens.
[0142] (1) Specimen preparation. Prepare and test a minimum of
three test specimens. If an oriented film cover material is used,
prepare and test both the warp and fill directions.
[0143] (2) Construction. Test specimens must include all materials
used in construction of the insulation (including batting, film,
scrim, tape etc.). Cut a piece of core material such as foam or
fiberglass, and cut a piece of film cover material (if used) large
enough to cover the core material. Heat sealing is the preferred
method of preparing fiberglass samples, since they can be made
without compressing the fiberglass ("box sample"). Cover materials
that are not heat sealable may be stapled, sewn, or taped as long
as the cover material is over-cut enough to be drawn down the sides
without compressing the core material. The fastening means should
be as continuous as possible along the length of the seams. The
specimen thickness must be of the same thickness as installed in
the airplane.
[0144] (3) Specimen Dimensions. To facilitate proper placement of
specimens in the sliding platform housing, cut non-rigid core
materials, such as fiberglass, 121/2 inches (318mm) wide by 23
inches (584 mm) long. Cut rigid materials, such as foam,
111/2.+-.1/4 inches (292 mm .+-.6 mm) wide by 23 inches (584 mm)
long in order to fit properly in the sliding platform housing and
provide a flat, exposed surface equal to the opening in the
housing.
[0145] (d) Specimen conditioning. Condition the test specimens at
70.+-.5.degree. F. (21.+-.2.degree. C.) and 55% .+-.10% relative
humidity, for a minimum of 24 hours prior to testing.
[0146] (e) Apparatus Calibration.
[0147] (1) With the sliding platform out of the chamber, install
the calorimeter holding frame. Push the platform back into the
chamber and insert the calorimeter into the first hole ("zero"
position). Close the bottom door located below the sliding
platform. The distance from the centerline of the calorimeter to
the radiant panel surface at this point must be 7.{fraction (1/2)}
inches .+-.1/8 (191 mm .+-.3). Prior to igniting the radiant panel,
ensure that the calorimeter face is clean and that there is water
running through the calorimeter.
[0148] (2) Ignite the panel. Adjust the fuel/air mixture to achieve
1.5 BTUs/ft.sup.2-second .+-.5% (1.7 Watts/cm.sup.2.+-.5%) at the
"zero" position. If using an electric panel, set the power
controller to achieve the proper heat flux. Allow the unit to reach
steady state (this may take up to 1 hour). The pilot burner must be
off and in the down position during this time.
[0149] (3) After steady-state conditions have been reached, move
the calorimeter 2 inches (51 mm) from the "zero" position (first
hole) to position 1 and record the heat flux. Move the calorimeter
to position 2 and record the heat flux. Allow enough time at each
position for the calorimeter to stabilize. Table 1 depicts typical
calibration values at the three positions.
1TABLE 1 Calibration Table Position BTU's/ft.sup.2 sec
Watts/cm.sup.2 "Zero" Position 1.5 1.7 Position 1 1.51-1.50-1.49
1.71-1.70-1.69 Position 2 1.43-1.44 1.62-1.63
[0150] (4) Open the bottom door, remove the calorimeter and holder
fixture. Use caution as the fixture is very hot.
[0151] (f) Test Procedure.
[0152] (1) Ignite the pilot burner. Ensure that it is at least 2
inches (51 mm) above the top of the platform. The burner must not
contact the specimen until the test begins.
[0153] (2) Place the test specimen in the sliding platform holder.
Ensure that the test sample surface is level with the top of the
platform. At "zero" point, the specimen surface must be 71/2 inches
.+-.1/8 inch (191 mm .+-.3) below the radiant panel.
[0154] (3) Place the retaining/securing frame over the test
specimen. It may be necessary (due to compression) to adjust the
sample (up or down) in order to maintain the distance from the
sample to the radiant panel (71/2 inches .+-.1/8 inch (191 mm.+-.3)
at "zero" position). With film/fiberglass assemblies, it is
critical to make a slit in the film cover to purge any air inside.
This allows the operator to maintain the proper test specimen
position (level with the top of the platform) and to allow
ventilation of gases during testing. A longitudinal slit,
approximately 2 inches (51 mm) in length, must be centered 3 inches
.+-.1/2 inch (76 mm.+-.13 mm) from the left flange of the securing
frame. A utility knife is acceptable for slitting the film
cover.
[0155] (4) Immediately push the sliding platform into the chamber
and close the bottom door.
[0156] (5) Bring the pilot burner flame into contact with the
center of the specimen at the "zero" point and simultaneously start
the timer. The pilot burner must be at a 27.degree. angle with the
sample and be approximately 1/2 inch (12 mm) above the sample. A
stop allows the operator to position the burner correctly each
time.
[0157] (6) Leave the burner in position for 15 seconds and then
remove to a position at least 2 inches (51 mm) above the
specimen.
[0158] (g) Report.
[0159] (1) Identify and describe the test specimen.
[0160] (2) Report any shrinkage or melting of the test
specimen.
[0161] (3) Report the flame propagation distance. If this distance
is less than 2 inches, report this as a pass (no measurement
required).
[0162] (4) Report the after-flame time.
[0163] (h) Requirements.
[0164] (1) There must be no flame propagation beyond 2 inches (51
mm) to the left of the centerline of the pilot flame
application.
[0165] (2) The flame time after removal of the pilot burner may not
exceed 3 seconds on any specimen.
[0166] Part VII--Test Method to Determine the Burnthrough
Resistance of Thermal/Acoustic Insulation Materials
[0167] Use the following test method to evaluate the burnthrough
resistance characteristics of aircraft thermal/acoustic insulation
materials when exposed to a high intensity open flame.
[0168] (a) Definitions.
[0169] Burnthrough time means the time, in seconds, for the burner
flame to penetrate the test specimen, and/or the time required for
the heat flux to reach 2.0 Btu/ft.sup.2sec (2.27 W/cm.sup.2) on the
inboard side, at a distance of 12 inches (30.5 cm) from the front
surface of the insulation blanket test frame, whichever is sooner.
The burnthrough time is measured at the inboard side of each of the
insulation blanket specimens.
[0170] Insulation blanket specimen means one of two specimens
positioned in either side of the test rig, at an angle of
30.degree. with respect to vertical.
[0171] Specimen set means two insulation blanket specimens. Both
specimens must represent the same production insulation blanket
construction and materials, proportioned to correspond to the
specimen size.
[0172] (b) Apparatus.
[0173] (1) The arrangement of the test apparatus must include the
capability of swinging the burner away from the test specimen
during warm-up.
[0174] (2) Test burner. The test burner must be a modified gun-type
such as the Park Model DPL 3400. Flame characteristics are highly
dependent on actual burner setup. Parameters such as fuel pressure,
nozzle depth, stator position, and intake airflow must be properly
adjusted to achieve the correct flame output.
[0175] (i) Nozzle. A nozzle must maintain the fuel pressure to
yield a nominal 6.0 gal/hr (0.378 L/min) fuel flow. A
Monarch-manufactured 80.degree. PL (hollow cone) nozzle nominally
rated at 6.0 gal/hr at 100 lb/in2 (0.71 MPa) delivers a proper
spray pattern.
[0176] (ii) Fuel Rail. The fuel rail must be adjusted to position
the fuel nozzle at a depth of 0.3125 inch (8 mm) from the end plane
of the exit stator, which must be mounted in the end of the draft
tube.
[0177] (iii) Internal Stator. The internal stator, located in the
middle of the draft tube, must be positioned at a depth of 3.75
inches (95 mm) from the tip of the fuel nozzle. The stator must
also be positioned such that the integral igniters are located at
an angle midway between the 10 and 11 o'clock position, when viewed
looking into the draft tube. Minor deviations to the igniter angle
are acceptable if the temperature and heat flux requirements
conform to the requirements of paragraph VII(e) of this
appendix.
[0178] (iv) Blower Fan. The cylindrical blower fan used to pump air
through the burner must measure 5.25 inches (133 mm) in diameter by
3.5 inches (89 mm) in width.
[0179] (v) Burner cone. Install a 12+0.125-inch (305.+-.3 mm)
burner extension cone at the end of the draft tube. The cone must
have an opening 6.+-.0.125-inch (152.+-.3 mm) high and
11.+-.0.125-inch (280.+-.3 mm) wide.
[0180] (vi) Fuel. Use JP-8, Jet A, or their international
equivalent, at a flow rate of 6.0.+-.0.2 gal/hr (0.378.+-.0126
L/min). If this fuel is unavailable, ASTM K2 fuel (Number 2 grade
kerosene) or ASTM D2 fuel (Number 2 grade fuel oil or Number 2
diesel fuel) are acceptable if the nominal fuel flow rate,
temperature, and heat flux measurements conform to the requirements
of paragraph VII(e) of this appendix.
[0181] (vii) Fuel pressure regulator. Provide a fuel pressure
regulator, adjusted to deliver a nominal 6.0 gal/hr (0.378 L/min)
flow rate. An operating fuel pressure of 100 lb/in 2 (0.71 MPa) for
a nominally rated 6.0 gal/hr 80.degree. spray angle nozzle (such as
a PL type) delivers 6.0.+-.0.2 gal/hr (0.378.+-.0.0126 L/min).
[0182] (3) Calibration Rig and Equipment.
[0183] (i) Construct individual calibration rigs to incorporate a
calorimeter and thermocouple rake for the measurement of heat flux
and temperature. Position the calibration rigs to allow movement of
the burner from the test rig position to either the heat flux or
temperature position with minimal difficulty.
[0184] (ii) Calorimeter. The calorimeter must be a total heat flux,
foil type Gardon Gage of an appropriate range such as 0-20
Btu/ft.sup.2-sec (0-22.7 W/cm.sup.2), accurate to .+-.3% of the
indicated reading. The heat flux calibration method must be in
accordance with paragraph VI(b)(7) of this appendix.
[0185] (iii) Calorimeter mounting. Mount the calorimeter in a 6- by
12-.+-.125 inch (152- by 305-.+-.3 mm) by 0.75.+-.0.125 inch (19
mm.+-.3 mm) thick insulating block which is attached to the heat
flux calibration rig during calibration. Monitor the insulating
block for deterioration and replace it when necessary. Adjust the
mounting as necessary to ensure that the calorimeter face is
parallel to the exit plane of the test burner cone.
[0186] (iv) Thermocouples. Provide seven 1/8-inch (3.2 mm) ceramic
packed, metal sheathed, type K (Chromel-alumel), grounded junction
thermocouples with a nominal 24 American Wire Gauge (AWG) size
conductor for calibration. Attach the thermocouples to a steel
angle bracket to form a thermocouple rake for placement in the
calibration rig during burner calibration.
[0187] (v) Air velocity meter. Use a vane-type air velocity meter
to calibrate the velocity of air entering the burner. An Omega
Engineering Model HH30A is satisfactory. Use a suitable adapter to
attach the measuring device to the inlet side of the burner to
prevent air from entering the burner other than through the
measuring device, which would produce erroneously low readings. Use
a flexible duct, measuring 4 inches wide (102 mm) by 20 feet long
(6.1 meters), to supply fresh air to the burner intake to prevent
damage to the air velocity meter from ingested soot. An optional
airbox permanently mounted to the burner intake area can
effectively house the air velocity meter and provide a mounting
port for the flexible intake duct.
[0188] (4) Test specimen mounting frame. Make the mounting frame
for the test specimens of 1/8-inch (3.2 mm) thick steel, except for
the center vertical former, which should be 1/4-inch (6.4 mm) thick
to minimize warpage. The specimen mounting frame stringers
(horizontal) should be bolted to the test frame formers (vertical)
such that the expansion of the stringers will not cause the entire
structure to warp. Use the mounting frame for mounting the two
insulation blanket test specimens.
[0189] (5) Backface calorimeters. Mount two total heat flux Gardon
type calorimeters behind the insulation test specimens on the back
side (cold) area of the test specimen mounting frame. Position the
calorimeters along the same plane as the burner cone centerline, at
a distance of 4 inches (102 mm) from the vertical centerline of the
test frame.
[0190] (i) The calorimeters must be a total heat flux, foil type
Gardon Gage of an appropriate range such as 0-5 Btu/ft.sup.2-sec
(0-5.7 W/cm.sup.2), accurate to .+-.3% of the indicated reading.
The heat flux calibration method must comply with paragraph
VI(b)(7) of this appendix.
[0191] (6) Instrumentation. Provide a recording potentiometer or
other suitable calibrated instrument with an appropriate range to
measure and record the outputs of the calorimeter and the
thermocouples.
[0192] (7) Timing device. Provide a stopwatch or other device,
accurate to .+-.1%, to measure the time of application of the
burner flame and burnthrough time.
[0193] (8) Test chamber. Perform tests in a suitable chamber to
reduce or eliminate the possibility of test fluctuation due to air
movement. The chamber must have a minimum floor area of 10 by 10
feet (305 by 305 cm).
[0194] (i) Ventilation hood. Provide the test chamber with an
exhaust system capable of removing the products of combustion
expelled during tests.
[0195] (c) Test Specimens.
[0196] (1) Specimen preparation. Prepare a minimum of three
specimen sets of the same construction and configuration for
testing.
[0197] (2) Insulation Blanket Test Specimen.
[0198] (i) For batt-type materials such as fiberglass, the
constructed, finished blanket specimen assemblies must be 32 inches
wide by 36 inches long (81.3 by 91.4 cm), exclusive of heat sealed
film edges.
[0199] (ii) For rigid and other non-conforming types of insulation
materials, the finished test specimens must fit into the test rig
in such a manner as to replicate the actual in-service
installation.
[0200] (3) Construction. Make each of the specimens tested using
the principal components (i.e., insulation, fire barrier material
if used, and moisture barrier film) and assembly processes
(representative seams and closures).
[0201] (i) Fire barrier material. If the insulation blanket is
constructed with a fire barrier material, place the fire barrier
material in a manner reflective of the installed arrangement For
example, if the material will be placed on the outboard side of the
insulation material, inside the moisture film, place it the same
way in the test specimen.
[0202] (ii) Insulation material. Blankets that utilize more than
one variety of insulation (composition, density, etc.) must have
specimen sets constructed that reflect the insulation combination
used. If, however, several blanket types use similar insulation
combinations, it is not necessary to test each combination if it is
possible to bracket the various combinations.
[0203] (iii) Moisture barrier film. If a production blanket
construction utilizes more than one type of moisture barrier film,
perform separate tests on each combination. For example, if a
polyimide film is used in conjunction with an insulation in order
to enhance the burnthrough capabilities, also test the same
insulation when used with a polyvinyl fluoride film.
[0204] (iv) Installation on testframe. Attach the blanket test
specimens to the test frame using 12 steel spring type clamps. Use
the clamps to hold the blankets in place in both of the outer
vertical formers, as well as the center vertical former (4 clamps
per former). The clamp surfaces should measure 1 inch by 2 inches
(25 by 51 mm). Place the top and bottom clamps 6 inches (15.2 cm)
from the top and bottom of the test frame, respectively. Place the
middle clamps 8 inches (20.3 cm) from the top and bottom
clamps.
[0205] (Note: For blanket materials that cannot be installed in
accordance with the above, the blankets must be installed in a
manner approved by the FAA.)
[0206] (v) Conditioning. Condition the specimens at
70.degree..congruent.5.degree. F. (21.degree..+-.2.degree. C.) and
55%.+-.10% relative humidity for a minimum of 24 hours prior to
testing.
[0207] (d) Preparation of Apparatus.
[0208] (1) Level and center the frame assembly to ensure alignment
of the calorimeter and/or thermocouple rake with the burner
cone.
[0209] (2) Turn on the ventilation hood for the test chamber. Do
not turn on the burner blower. Measure the airflow of the test
chamber using a vane anemometer or equivalent measuring device. The
vertical air velocity just behind the top of the upper insulation
blanket test specimen must be 100.+-.50 ft/min (0.51.+-.0.25 m/s).
The horizontal air velocity at this point must be less than 50
ft/min (0.25 m/s).
[0210] (3) If a calibrated flow meter is not available, measure the
fuel flow rate using a graduated cylinder of appropriate size. Turn
on the burner motor/fuel pump, after insuring that the igniter
system is turned off. Collect the fuel via a plastic or rubber tube
into the graduated cylinder for a 2-minute period. Determine the
flow rate in gallons per hour. The fuel flow rate must be
6.0.+-.0.2 gallons per hour (0.378.+-.0.0126 L/min).
[0211] (e) Calibration.
[0212] (1) Position the burner in front of the calorimeter so that
it is centered and the vertical plane of the burner cone exit is
4.+-.0.125 inches (102.+-.3 mm) from the calorimeter face. Ensure
that the horizontal centerline of the burner cone is offset 1 inch
below the horizontal centerline of the calorimeter. Without
disturbing the calorimeter position, rotate the burner in front of
the thermocouple rake, such that the middle thermocouple (number 4
of 7) is centered on the burner cone.
[0213] Ensure that the horizontal centerline of the burner cone is
also offset 1 inch below the horizontal centerline of the
thermocouple tips. Re-check measurements by rotating the burner to
each position to ensure proper alignment between the cone and the
calorimeter and thermocouple rake. (Note: The test burner mounting
system must incorporate "detents" that ensure proper centering of
the burner cone with respect to both the calorimeter and the
thermocouple rakes, so that rapid positioning of the burner can be
achieved during the calibration procedure.)
[0214] (2) Position the air velocity meter in the adapter or
airbox, making certain that no gaps exist where air could leak
around the air velocity measuring device. Turn on the blower/motor
while ensuring that the fuel solenoid and igniters are off. Adjust
the air intake velocity to a level of 2150 ft/min, (10.92 m/s) then
turn off the blower/motor. (Note: The Omega HH30 air velocity meter
measures 2.625 inches in diameter. To calculate the intake airflow,
multiply the cross-sectional area (0.03758 ft.sup.2) by the air
velocity (2150 ft/min) to obtain 80.80 ft.sup.3/min. An air
velocity meter other than the HH30 unit can be used, provided the
calculated airflow of 80.80 ft.sup.3/min (2.29 m.sup.3/min) is
equivalent.)
[0215] (3) Rotate the burner from the test position to the warm-up
position. Prior to lighting the burner, ensure that the calorimeter
face is clean of soot deposits, and there is water running through
the calorimeter. Examine and clean the burner cone of any evidence
of buildup of products of combustion, soot, etc. Soot buildup
inside the burner cone may affect the flame characteristics and
cause calibration difficulties. Since the burner cone may distort
with time, dimensions should be checked periodically.
[0216] (4) While the burner is still rotated to the warm-up
position, turn on the blower/motor, igniters and fuel flow, and
light the burner. Allow it to warm up for a period of 2 minutes.
Move the burner into the calibration position and allow 1 minute
for calorimeter stabilization, then record the heat flux once every
second for a period of 30 seconds. Turn off burner, rotate out of
position, and allow to cool. Calculate the average heat flux over
this 30-second duration. The average heat flux should be
16.0.+-.0.8 Btu/ft.sup.2 sec (18.2.+-.0.9 W/cm.sup.2).
[0217] (5) Position the burner in front of the thermocouple rake.
After checking for proper alignment, rotate the burner to the
warm-up position, turn on the blower/motor, igniters and fuel flow,
and light the burner. Allow it to warm up for a period of 2
minutes. Move the burner into the calibration position and allow 1
minute for thermocouple stabilization, then record the temperature
of each of the 7 thermocouples once every second for a period of 30
seconds. Turn off burner, rotate out of position, and allow to
cool. Calculate the average temperature of each thermocouple over
this 30-second period and record. The average temperature of each
of the 7 thermocouples should be 1900.degree. F..+-.100.degree. F.
(1038.+-.56.degree. C.).
[0218] (6) If either the heat flux or the temperatures are not
within the specified range, adjust the burner intake air velocity
and repeat the procedures of paragraphs (4) and (5) above to obtain
the proper values. Ensure that the inlet air velocity is within the
range of 2150 ft/min .+-.50 ft/min (10.92.+-.0.25 m/s).
[0219] (7) Calibrate prior to each test until consistency has been
demonstrated. After consistency has been confirmed, several tests
may be conducted with calibration conducted before and after a
series of tests.
[0220] (f) Test Procedure.
[0221] (1) Secure the two insulation blanket test specimens to the
test frame. The insulation blankets should be attached to the test
rig center vertical former using four spring clamps positioned
according to the criteria of paragraph (c)(4) or (c)(4)(i) of this
part of this appendix.
[0222] (2) Ensure that the vertical plane of the burner cone is at
a distance of 4.+-.0.125 inch (102.+-.3 mm) from the outer surface
of the horizontal stringers of the test specimen frame, and that
the burner and test frame are both situated at a 30.degree. angle
with respect to vertical.
[0223] (3) When ready to begin the test, direct the burner away
from the test position to the warm-up position so that the flame
will not impinge on the specimens prematurely. Turn on and light
the burner and allow it to stabilize for 2 minutes.
[0224] (4) To begin the test, rotate the burner into the test
position and simultaneously start the timing device.
[0225] (5) Expose the test specimens to the burner flame for 4
minutes and then turn off the burner. Immediately rotate the burner
out of the test position.
[0226] (6) Determine (where applicable) the burnthrough time, or
the point at which the heat flux exceeds 2.0 Btu/ft.sup.2-sec (2.27
W/cm.sup.2).
[0227] (g) Report.
[0228] (1) Identify and describe the specimen being tested.
[0229] (2) Report the number of insulation blanket specimens
tested.
[0230] (3) Report the burnthrough time (if any), and the maximum
heat flux on the back face of the insulation blanket test specimen,
and the time at which the maximum occurred.
[0231] (h) Requirements.
[0232] (1) Each of the two insulation blanket test specimens must
not allow fire or flame penetration in less than 4 minutes.
[0233] (2) Each of the two insulation blanket test specimens must
not allow more than 2.0 Btu/ft.sup.2-sec (2.27 W/cm.sup.2) on the
cold side of the insulation specimens at a point 12 inches (30.5
cm) from the face of the test rig.
[0234] [Amdt. 25-32, 37 FR 3972, Feb. 24, 1972]
Test Methods Utilized
[0235] Hydrophobicity
[0236] The ability of a substrate to be wetted was evaluated using
mixtures of water and isopropyl alcohol (IPA). The following test
solutions of IPA in water were first prepared: 16%, 18%, 20%, 22%,
24% and 26% (all percentages were by volume). Each substrate to be
evaluated was dried for one hour at 60.degree. C. in an air
circulating oven and then allowed to cool to room temperature
before testing. Circles measuring about 1 inch (2.54 cm) were then
drawn on a surface of the substrate. Next, about 0.5 mL of the 18%
IPA solution was placed inside a first circle using a disposable
transfer pipette. The IPA solution was then observed to determine
whether or not it wetted out/into the substrate. If it did wet out,
it was graded as a "+", and, if it did not, it was graded as a "-".
This procedure was repeated using the other IPA solutions and
circles. In all cases reported herein, it was evident when the
solutions wetted the substrate and when they did not. In this
manner, a crossover point was determined at which the EPA solution
wetted out/into the substrate.
[0237] Using this test procedure, the hydrophobicity of melt-blown
fibrous web insulation materials containing 55-100 percent by
weight polypropylene (primarily isotactic) and 0-45 percent by
weight polyethylene terephthalate (PET) was evaluated. The results
are reported in Table 1 below. The experiments were repeated
several times, using both embossed and un-embossed webs, with
similar results. The fibrous web materials used as Samples 1-3 are
available from 3M Company, St. Paul, Minn. The 100 percent
polypropylene web was prepared using a polypropylene feedstock
having a melt flow index of 350 grams/10 minutes (available as FINA
350 from ATO FINA, Deer Park, Tex.) using a melt-blowing process to
provide individual fibers having an effective diameter of less than
12 micrometers (.mu.m), which formed a web having a thickness of
approximately 1.0-1.5 centimeters (cm) and an areal weight of
approximately 200 grams/meter.sup.2.
2 Polypropylene:Polyester Sample Insulation Material (w:w) 1 3M
.TM. THINSULATE .TM. 55:45 ACOUSTIC INSULATION TC-3302-60 2 3M .TM.
THINSULATE .TM. 65:35 ACOUSTIC INSULATION AU-2020-1 3 3M .TM.
THINSULATE .TM. 80:20 ACOUSTIC INSULATION 2099 4 Melt-blown
Polypropylene Web 100:0
[0238]
3 TABLE 1 % Isopropyl Alcohol in Water Sample % Polypropylene 18 20
22 24 26 1 55 - + + + + 2 65 - - + + + 3 80 - - - + + 4 100 - - - -
+
[0239] A sample of a non-woven web comprising polyethylene-coated
poly(ethylene terephthalate) staple fibers was also tested using a
solution of 16 percent IPA in water, and wetting was observed.
[0240] For reference, the surface tension (gamma) value at
20.degree. C. for linear polyethylene (infinite molecular weight)
is reported as 36.8, that of polypropylene (atactic, MWn=3000) as
28.3, and that of poly(ethylene terephthalate) (hereinafter, "PET",
MWn=25,000) as 44.6 by J. Bicerano in Prediction of Polymer
Properties, pp. 195-196, Marcel Dekker, Inc., New York (1996). In
the Polymer Handbook, J. Brandup, E. Immergut, and E. Grulke (Ed.),
4.sup.th Edition, pp. 524 and 530, John Wiley & Sons, Inc., New
York, these values are reported as 36.8 (infinite molecular
weight), 29.4 (atactic, no MW given), and 44.6 (MWn=25,000),
respectively, along with values of 29.4 for isotactic polypropylene
(no MW given) and 30.1 for a mixture of isotactic and atactic
polypropylene.
[0241] Radiant Panel Test and Burnthrough Test
[0242] Radiant panel testing and burnthrough testing were carried
out according to the above-detailed Federal Aviation Administration
regulations and procedures in essentially the same manner as that
described at columns 18-24 of U.S. Pat. No. 6,670,291 (Tompkins et
al.), the descriptions of which are incorporated herein by
reference.
Examples 1-4
[0243] In these examples, various thermal acoustic insulation
blankets were prepared in rollstock form using a continuous
process. The resulting blankets comprised materials in the form of
layers that were substantially coextensive.
Example 1
[0244] 3M.TM. NEXTEL.TM. Flame Stopping Dot Paper (an alumina
fiber-based paper fire barrier material having a basis weight of
70-80 grams/meter.sup.2, available from 3M Company, St. Paul,
Minn.) was used to prepare rollstock of a two-layer thermal
acoustic insulation blanket. The 3M.TM. NEXTEL.TM. Flame Stopping
Dot Paper was fed through a melt-blown process chamber essentially
as described at column 8, line 49, to column 10, line 18, of U.S.
Pat. No. 5,841,081 (Thompson et al.) to collect a non-woven,
melt-blown blend of polypropylene/PET (65:35/w:w) fibers on one
side of the fire barrier material. The resulting thermal acoustic
insulation blanket in rollstock form comprised a fibrous web
(having a thickness of approximately 1 inch (2.5 cm) and an areal
weight of approximately 123 grams/meter.sup.2) on a paper fire
barrier.
Example 2
[0245] Example 1 was repeated with the following modification:
3M.TM. NEXTEL.TM. Flame Stopping Coated Paper (a vermiculite
coated, alumina fiber-based paper fire barrier material having a
basis weight of 70-80 grams/meter.sup.2, available from 3M Company,
St. Paul, Minn.) was used instead of 3M.TM. NEXTEL.TM. Flame
Stopping Dot Paper. The resulting thermal acoustic insulation
blanket in rollstock form comprised a fibrous web (having a
thickness of approximately 1 inch (2.5 cm) and an areal weight of
approximately 123 grams/meter.sup.2) on a paper fire barrier.
Example 3
[0246] INSULFAB 331 (a lightweight, high strength vapor barrier
comprising a scrim-reinforced, metallized polyvinyl fluoride film
(available as TEDLAR from E. I. DuPont de Nemours Company,
Wilmington, Del.) available from Chase Facile, Incorporated,
Paterson, N.J.) was used to prepare a three-layer thermal acoustic
insulation blanket in a rollstock form. One piece of INSULFAB 331A
was laminated to 3M.TM. NEXTEL.TM. Flame Stopping Coated Paper.
This intermediate two-layer laminate was fed through a melt-blown
process chamber essentially as described in Example 1 to collect a
non-woven, melt-blown blend of polypropylene/PET (65:35/w:w) fibers
such that the non-woven melt-blown fibers contacted the fire
barrier side of the laminate. A thermal acoustic insulation blanket
comprising a paper fire barrier with a vapor barrier laminated to
one side and a fibrous web (having a thickness of approximately 1
inch (2.5 cm) and an areal weight of approximately 123
grams/meter.sup.2) on the opposite side was obtained in rollstock
form.
Example 4
[0247] Example 3 was repeated with the following modification: a
light coat of adhesive (3M.TM. SUPER SPRAY 77 ADHESIVE, available
from 3M Company, St. Paul, Minn.) was applied to the ceramic paper
side of the intermediate fire barrier/vapor barrier laminate prior
to feeding it through the melt-blown process chamber. A thermal
acoustic insulation blanket comprising a paper fire barrier with a
vapor barrier laminated to one side and a fibrous web (having a
thickness of approximately 2 inches (5.0 cm) and an areal weight of
approximately 121 grams/meter.sup.2) adhered to the opposite side
was obtained in rollstock form.
Examples 5-7
[0248] In these examples, various thermal acoustic insulation
blankets were prepared using manual lay-up methods and were
evaluated using radiant panel and burnthrough tests.
Example 5
[0249] Two pieces of INSULFAB 2000A (a lightweight, high strength
vapor barrier comprising a scrim-reinforced polyimide film,
available from Chase Facile, Incorporated, Paterson, N.J.) were
used to prepare a four-layer thermal acoustic insulation blanket.
More specifically, two pieces of INSULFAB 2000A were used to
encapsulate one piece each of 1) 3M.TM. NEXTEL.TM. Flame Stopping
Dot Paper (fire barrier) and 2) a web formed from a non-woven,
melt-blown blend of polypropylene/PET (65:35/w:w) fibers and having
a thickness of approximately 1 inch (2.5 cm) and an areal weight of
approximately 417 grams/meter.sup.2 (commercially available as
3M.TM. THINSULATE.TM. ACOUSTIC INSULATION AU 4020-6 from 3M
Company, St. Paul, Minn.) such that the adhesive side of the
INSULFAB 2000A sheets contacted the fire barrier and the non-woven
web. The pieces were laid up so as to provide an overhanging edge
of the INSULFAB 2000A layers around the outer border of the fire
barrier and non-woven web pieces. The facing adhesive edges of the
two INSULFAB 2000A layers were heat sealed together using a tool
having a temperature of between 300 and 320.degree. F. (149 and
160.degree. C.) to produce a final thermal acoustic insulation
sample.
[0250] For the "Radiant Panel Test," the sample comprised two
pieces of INSULFAB 2000A that had dimensions of approximately 13
inches by 21 inches (33.0 cm by 53.3 cm) and fire barrier and
non-woven web pieces that had dimensions of approximately 12 inches
by 20 inches (30.5 cm by 50.8 cm), and the overhanging edge of the
INSULFAB 2000A layers was approximately 0.5 inches (1.3 cm). For
the "Burnthrough Test," the sample comprised two pieces of INSULFAB
2000A that had dimensions of approximately 34 inches by 38 inches
(86.4 cm by 96.5 cm) and fire barrier and non-woven web pieces that
had dimensions of approximately 32 inches by 36 inches (81.3 cm by
91.4 cm), and the overhanging edge of the INSULFAB 2000A layers was
approximately 1.0 inch (2.5 cm). The samples were tested according
to the "Radiant Panel Test" and "Burnthrough Test" procedures
described above and passed the tests.
Example 6
[0251] Example 5 was repeated with the following modification: two
layers of 3M.TM. THINSULATE.TM. ACOUSTIC INSULATION AU 4020-6
material were positioned on one side of the fire barrier material.
The resulting thermal acoustic insulation blanket samples passed
the "Radiant Panel Test" and the "Burnthrough Test".
Example 7
[0252] Example 5 was repeated with the following modification:
3M.TM. NEXTEL.TM. Flame Stopping Coated Paper was used in place of
3M.TM. NEXTEL.TM. Flame Stopping Dot Paper. The resulting thermal
acoustic insulation blanket was tested and passed the "Burnthrough
Test".
[0253] The referenced descriptions contained in the patents, patent
documents, and publications cited herein are incorporated by
reference as if each were individually incorporated. Various
unforeseeable modifications and alterations to this invention will
become apparent to those skilled in the art without departing from
the scope and spirit of this invention. It should be understood
that this invention is not intended to be unduly limited by the
illustrative embodiments and examples set forth herein and that
such examples and embodiments are presented by way of example only,
with the scope of the invention intended to be limited only by the
claims set forth herein as follows:
* * * * *