Method of determining thermal conductivity of fiber insulation

Claim 2

A process for the determination of the apparent thermal conductivity of a low density matted inorganic fiber body without significant physical distortion or heating of the body, which commprises impinging a beam of visible light on a surface of the body; detecting at a point on the surface of the body substantially opposite to the point of impingment the amount of said visible light transmitted through said body; and thereafter determining said apparent thermal conductivity from said amount of transmitted visible light according to a predetermined correlation.

Claim 3

The process of claim 1 wherein the beam of visible light traverses said matted inorganic fiber body on a line substantially normal to the plane of principal orientation of the fibers in said matted mineral fiber body.

Claim 4

The process of claim 1 wherein said thermal conductivity measurement is made continuously.

Claim 5

The process of claim 1 wherein the density of said matted inorganic fiber body is not more than 2.0 lbs/ft 3 .

Claim 6

The process of claim 6 wherein said density is not more than 1.6 lbs/ft 3 .

Claim 7

The process of claim 1 wherein said inorganic fiber comprises glass fiber.

Claim 8

Apparatus for determining the thermal conductivity of a low density matted inorganic fiber body by means of light transmission and without significant physical distortion or heating of the body, which comprises: a. a light source; b. light sensing means positioned to detect essentially only that light emitted from said light source which passes through said matted inorganic fiber body; c. means for converting the amount of transmitted light sensed by said sensing means into a proportional electrical signal; and d. means for converting said proportional electrical signal by a predetermined correlation into a comprehensible output proportional to the thermal conductivity of said matted inorganic fiber body.

Claim 9

Apparatus for determining the thermal conductivity of a low density matted inorganic fiber body by means of light transmission and without significant physical distortion or heating of the body, which comprises: a. a light source; b. light sensing means positioned to detect essentially only that light emitted from said light source which passes through said matted inorganic fiber body; c. means for converting the amount of transmitted light sensed by said sensing means into a proportional electrical signal; and d. means for converting said proportional electrical signal by a predetermined correlation into a comprehensible output proportional to the thermal conductivity of said matted inorganic fiber body.

Claim 10

The apparatus of claim 7 wherein said light sensing means is positioned so as to detect only that light emitted from said light source which traverses said matted inorganic fiber body on a line substantially normal to the plane of principal orientation of the fibers in said matted inorganic fiber body.

Claim 11

The apparatus of claim 7 further comprising means for moving said low density matted inorganic fiber body into a position between said light source and said sensing means.

Claim 12

The apparatus of claim 7 wherein said light source comprises a plurality of individual lights arranged in an array transversely across the path of motion of said body, and said sensing means comprises a plurality of individual sensors, each positioned on the opposite side of said body from and directly opposite a corresponding individual light.

Claim 13

The apparatus of claim 10 wherein said light source comprises a single line light source extending transversely across said matted inorganic fiber body and having a uniform light density throughout its length.