A-A-52169 Insulation; Sound, Vibration, And ThermalThis CID covers the physical, chemical, and performance characteristics of the composite material used to make insulating pads for use on the High Mobility Multipurpose Wheeled Vehicle HMMWV series of vehicles and for other similar applications. The insulating pads are used as a thermal, sound, and vibration barrier. The insulating pad is made of five layers of material consisting of the following components: a deep twist outer vinyl wear surface with a cloth reinforcement backing; a sound barrier layer; a closed cell acoustical and thermal foam insulation layer; a high temperature needle mat thermal blanket layer; and a fiberglass cloth reinforced vinyl and mylar backing see figure 1.

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A-A-52169B

2. SALIENT CHARACTERISTICS.

2.1 Materials. Unless otherwise specified herein or in the applicable engineering drawing (AED), the materials used shall be in accordance with the manufacturer's material specification/drawings. The use of recovered material made in compliance with regulatory requirements is acceptable providing all requirements of this CID are met (see 5.5).

2.2 Design and construction. The five components of the insulating pad composite material shall be designed and constructed to requirements specified herein.

2.2.1 Vinyl wear surface (outer). The deep twist outer vinyl wear surface component shall have a cloth reinforcement backing and shall conform to table I.

TABLE I. Vinyl wear surface (outer) component.

Characteristic

Requirement

Color Thickness Temperature limits Tensile strength Tear strength Weatherometer

Abrasion resistance

Green 383, color no. 34094 per FED-STD-595.

1.02 to 1.14 millimeter (mm).

-46 to +121 degrees Celsius ( C).

32 x 14 kilogram (kg) minimum.

7 x 8 kg minimum.

ASTM D-1499, 200 hour test (slight loss of gloss permitted)

Less than 0.25% weight loss at 500 G/GS - 17/1,000 cycles, using a Taber Abrader, in accordance with ASTM D3389.

2.2.2 Sound barrier. The sound barrier component shall conform to table II.

TABLE II. Sound barrier component.

Characteristic

Requirement

Color Temperature Mass Flammability

Black.

-46 to +121 C

3.90 to 4.88 kg/square meter (m2 ).

5 cm/minute, maximum in accordance with SAE J369

2.2.3 Closed cell foam. The acoustical and thermal insulation component shall be closed cell foam (such as Ensolite) and shall conform to table III.

2.2.4 High temperature needle mat (HTNM). Except as otherwise specified in table IV, the

HTNM component shall conform to MIL-I-16411.