Fire protective device

A fire protective insulating device of a generally boxlike configuration, having one end adapted to be placed about an electrical motor to be protected from a fire and including panel members connected together by non-flammable means which enclose said device around said motor to retain said device's enclosing function during a fire in order to isolate said motor from fire damage, and said fire protective insulating device being further defined as including:

• a plurality of layers of resilient and compressible non-combustible insulative material, said insulative material mechanically compressed to a density between about two and about twenty-four pounds per cubic foot by a plurality of compressive fastener means positioned through said insulative material, and constructed of a material which is substantially less resistant to high temperature than is said insulative material, said insulative material being capable of mechanical expansion to a density of about one to about twelve pounds per cubic foot, having at least one outer layer formed from a ceramic fiber and at least one inner layer formed from a glass fiber blanket, and constituting the surface of said insulating device to be adjacent to the exterior surface of the electrical motor when placed thereabout;
• scrim means about the exterior of the compressed insulative material further mechanically compressing said insulative material, said scrim means also being constructed of material which is substantially less resistant to high temperature than is said insulative material, whereby when said fire protective insulating device is subjected to a fire the structural integrity of said fastener means and said scrim means is decreased, thereby allowing the insulative material to expand mechanically to a density of about one to about twelve pounds per cubic foot;
• and
• closure members included in said end of said generally boxlike configured fire protective insulating device which substantially overlap upon closure and are stitched with non-flammable stitching means to maintain the enclosing function of said device during a fire, whereby said closure members provide double thickness of insulation about one surface of the motor to be protected from fire when said insulative device is sealed about said motor.