JPS60209067A - Sound absorbing and heat insulating cylinder of glass fiber needle mat - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] A sound-absorbing and heat-insulating pipe made by winding layers around the outer surface of a pipe is used for fishing. It is a nonwoven fabric that is cut into 0 mm pieces, opened into cotton-like fibers, and laminated into layers using a needle punch method. Conventionally, when molding a heat-insulating pipe using this glass fiber mat, the glass fiber mat is immersed in a water-soluble resin containing active ingredients a to Scs, wrapped around a metal pipe, and the resin content is squeezed out to an appropriate extent and dried. It is made by The disadvantages of this product are that no matter how much the squeezing of the resin is strengthened, the moisture content before drying is 3 to 3 times the weight of the mat, so drying takes a long time, and squeezing reduces the density of the cylinder. Go up O. tS
~O. Ko. t 77/am”, and only a cylinder with low elasticity could be formed.

Another problem with glass fibers is that each fiber melts near its softening point, causing fusion between the fibers and causing the entire fiber to shrink. As a result, the shape of the heat insulating material may be significantly deformed, the heat insulating layer may become thin, cracks may occur, or spaces may be created, causing the heat insulating material to collapse. Molded products used as insulation materials are bulky and have low density, so if local overheating occurs even for a short period of time, rapid contraction will occur in that area, causing local deformation and melting, making the entire product unusable. be.

The present invention aims to overcome these drawbacks of conventional products by using a nonwoven fabric in which glass fibers are impregnated with a phosphate suspension, thereby providing a low-density, highly heat-resistant cylindrical body.

That is, the present invention provides the following formulas:
If J%M is Mg, ///,! A mixture of aluminum phosphorus or/and magnesium phosphate represented by Nj) and one or more types of refractory inorganic powder such as alumina, kaolin, bentonite, p-stone, feldspar, etc. A phosphate suspension is impregnated into a non-woven fabric consisting of a needle mat of glass fibers, which is placed in a layered cylindrical sound-absorbing and insulating tube.

In the present invention, aluminum phosphate and/or magnesium phosphate represented by the above formula are used to impart heat resistance to the glass fibers to be impregnated. In order to improve the sound absorption and heat resistance of the sound-absorbing and heat-insulating cylinder, one or more types of refractory inorganic powders such as finely powdered alumina, kaolin, bentonite, loathite, and feldspar are preferably used.

The mixing ratio of phosphate and refractory inorganic powder such as alumina is /
:(7, Ko~S.

The method for forming the sound-absorbing and heat-insulating cylinder according to the present invention is as follows.

First, a phosphoric acid aqueous solution is diluted with water, a refractory inorganic powder such as alumina is added thereto, and the mixture is sufficiently stirred to form a suspension (slurry) of a phosphate aqueous solution - a refractory inorganic powder such as alumina. Prepare.

The prepared slurry is impregnated into the glass fiber product shown in FIG. 1 - Dormat non-woven fabric, and wrapped in a layer around the Venus tube in the second viJ, and shaped as shown in the gJ diagram. Next/-0℃
The tube was dried for about 1 hour, then heated to 300°C and fired for 1 hour, and the Venus tube was taken out (Figure 1). Note that the slurry concentration is 10 to 5 ocs, and the amount of impregnation to the glass fiber is 30 to 10 Q%.

The present invention will be explained below based on Examples.

Example 1 Monomethylaluminum phosphate 30% aqueous solution 10009
was diluted with 2000 ml of water, 1000 g of alumina was added to this aqueous solution, and the mixture was thoroughly stirred.
A monomethyl aluminum phosphate-alumina slurry of q, s% was prepared. In this slurry 1c 7~g m
A needle mat made of glass fiber having a thickness of m and a density of o and t I/amB was impregnated so that the amount of impregnation with respect to the fibers was 100%. Next, this needle mat has an outer diameter of 100 mm.
mm, wrapped in a single layer around a 7m long Venus tube and formed into l
Dry for #1 hour at -0°C. Next, the temperature was raised to 300°C, and the Venus was taken out after firing for one hour. The physical properties of the obtained cylindrical needle mat were as follows.

Wall thickness 10mm Density O0λ9/c+a' Insulation property 0.0 core9 Fireproof temperature SσO℃ Example comonocarbon aluminum phosphate spring magnesium [Aj (H*
SO% aqueous solution of 1:1 weight ratio mixture of POa)s and Mg(H,PO,)〕1000ml water, 2000m
1 and add kaolin clay to this aqueous solution.
The mixture was added and sufficiently stirred and mixed to prepare a phosphate-kaolin slurry having a solid content of 1.3°C%.

In this slurry, the density of 10 mm thick is 0. The glass fiber needle mat prepared by /v et al. 3 was impregnated with an impregnation amount of 1-0%. Next, this needle mat has an outer diameter of /3
0mm, length 0. The mixture was wrapped in a single layer around a metal tube of gm and dried at 740° C. for about 1 hour. Next, the temperature was raised to 320° C. and fired for one hour, and the Venus was taken out. The physical properties of the obtained cylindrical needle mat were as follows.

Thickness /jmm Density o, al/cal" Insulation property θ, θco refractory temperature 710°C As described above, according to the present invention, a nonwoven fabric in which glass fiber is impregnated with phosphate-refractory inorganic powder slurry As a result, a sound-absorbing and heat-insulating cylinder with low density and high heat resistance can be obtained.

[Brief explanation of the drawing]

Figure 1 is a front view of the glass fiber product - Dormat nonwoven fabric with slurry impregnated on both sides, Figure 2 is a front view of the nonwoven fabric of Figure #I1 wrapped around a metal tube, and No. FIG. 7 is a front view of the completed sound-absorbing and heat-insulating tube. In the figure, l...Glass fiber product - Dormat nonwoven fabric, c. 3. Phosphate aqueous solution - slurry of refractory inorganic powder such as alumina, da.. Metal pipe. Note that the same reference numerals in each figure indicate the same or equivalent parts. Patent applicant: Nihon Kagaku Kogyo Co., Ltd., Ltd., Figure 1

Claims (1)

[Claims] (In the formula, M is AJ or Mg, R is H%C1(, group or HOCH, CH, group, &m is l/ when M is A, l)
2~When JSM is Mg, t//, s-, y] and/or magnesium phosphate, and refractory inorganic powder such as alumina, kaolin, bentonite, lowite, feldspar, etc. Sound absorption of a glass fiber needle mat, in which a nonwoven fabric made of a glass fiber needle mat is impregnated with a suspension of one or more phosphates, and the nonwoven fabric is formed into a layered cylindrical body. Insulated tube.