JPH0524020A - Manufacture of inorganic silicate tubular foam - Google Patents

Abstract

PURPOSE:To manufacture lightweight inorganic refractory tube in continuous form having the length of 1m or longer with favorable workability by a method wherein forming tube is removed from inorganic silicate foam, which is hardened on the forming tube after the hardening of slurry and a jig is held integrally with the foam. CONSTITUTION:A pressing piston 3 is slidably arranged on one end side. One end part of a forming tube 8, which is horizontally arranged in a forming device 1 having a stock feeding chamber 5 and the length of which is 1m or longer, is connected with the other end side of the pressing piston 3. At the same time, a tubular or columnar jig 10, the diameter of which is smaller than the inner diameter of the forming tube 8, is concentrically inserted in the forming tube 8. After self-hardening inorganic silicate foam slurry is fed in the stock feeding chamber 5, the slurry is pressed with the piston 3 so as to be tubularly filled between the forming tube 8 and the jig 10. Next, after the hardening of the slurry, the forming tube 8 and the jig 10 are removed from a tubularly hardened inorganic silicate foam. Thus, inorganic refractory tube in continuous form having the length of 1m or longer can be easily and surely manufactured with favorable workability.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a fireproof tube, and further an inorganic silicate foam cylinder used as a heat resistant, heat insulating tube or the like.

[0002]

2. Description of the Related Art Conventionally, the problems to be solved by the invention
Ceramic pipes and the like are known as inorganic fireproof pipes, but these pipes are heavy, have poor handleability, and are long pipes.
It is about cm, which is troublesome because it must be connected to each other when a long tube of 1 m or more is required.

For this reason, it is desired that the inorganic fireproof tube is lightweight and long, but when manufacturing a long inorganic fireproof tube,
Normally, a molding pipe must be erected and molded, and a considerably high pressure is required when supplying and filling an inorganic molding material to the molding pipe, which is poor in workability and efficiency. It has been difficult to manufacture a long inorganic refractory tube having a relatively thin film thickness.

The present invention has been made in view of the above circumstances.
It is an object of the present invention to provide a method capable of efficiently manufacturing a lightweight inorganic fireproof tube having a length of 1 m or more with good workability and capable of easily and reliably producing a long fireproof tube having a thin film thickness.

[0005]

Means and Actions for Solving the Problems As a result of intensive studies for achieving the above object, the present inventor has found that a self-curing inorganic silicate foam slurry, particularly a density of 0.6 to 0.9 g /
The cm ³ slurry has good fluidity and shape retention, easily flows with a relatively small force, smoothly penetrates into narrow gaps, and retains its shape when the force is removed, and further flows. The above slurry can be hardened while maintaining its shape without causing any damage. In this case, the slurry flows in the horizontal direction without any problem due to the force from the horizontal direction, and therefore, the flow and the shape are maintained well even when the molding pipe is horizontally arranged. , Curing is done,
Even if the molding pipe is a long pipe having a length of 1 m or more, for example, 2 m, a small-diameter cylindrical or columnar jig is inserted into the molding pipe, and the slurry is flowed in the gap between the molding pipe and the jig. When injecting, it was found that even if this gap is narrow, for example, about 5 mm, there is no problem at all, and a long and thin fireproof tube can be easily obtained.

Therefore, according to the present invention, the pressing piston is slidably disposed on one end side, and the length is arranged horizontally in the molding apparatus in which the raw material supply chamber is formed on the other end side of the pressing piston. While connecting one end of the molding pipe of 1 m or more,
A cylindrical or columnar jig having a smaller diameter than the tube is inserted into the molding tube concentrically with the tube, and a self-curing inorganic silicate foam slurry is supplied to the raw material supply chamber, and then the slurry is removed by the piston. An inorganic silicate foam in which the slurry is cylindrically filled between the molding pipe and the jig by pressing, and the slurry is hardened, and then the molding pipe and the jig are hardened cylindrically. Or the curing of the slurry, the molding tube is removed from the cylindrically cured inorganic silicate foam, and the jig is held integrally with the foam. The present invention provides a method for producing an inorganic silicate foam cylinder.

The present invention will be described in more detail below. In the present invention, for example, a molding apparatus and a molding pipe as shown in FIG. 1 are used.

That is, in FIG. 1, reference numeral 1 indicates that a pressing piston 3 is slidably arranged at one end side in a horizontal cylindrical molding apparatus main body 2 and a truncated cone-shaped guide body 4 is arranged at the other end side. Main body 2
A raw material supply chamber 5 is formed between the pressing piston 3 and the guide body 4, and a raw material supply hopper 6 is provided above the raw material supply chamber 5 as a main body. It is provided by connecting to 2. A closed piston 7 is slidably provided in the hopper 6, and the closed piston 7 moves upward to open the hopper 6,
The self-hardening inorganic silicate slurry is introduced and supplied from the hopper 6 into the raw material supply chamber 5, and after the slurry is supplied, the sealing piston 7 descends to close the hopper 6, thereby sealing the main body 2. ing.

A molding pipe 8 is horizontally arranged, is removably fitted in the molding apparatus 1 along the horizontal direction, and has the other end closed by a cap 9.
Inside the tube 8, a cylindrical or columnar jig 10 (a cylindrical jig is shown in the drawing) having a small diameter is concentrically arranged.

When an inorganic silicate foam cylinder is manufactured using such an apparatus, the raw material supply chamber 5 is used as described above.
After supplying the self-curing inorganic silicate foam slurry into the
The pressing piston 3 is advanced to press the slurry, whereby the slurry passes through the clearance between the main body 2 and the guide body 4 and fills the clearance 11 between the molding pipe 8 and the jig 10. After filling, the molding pipe 8 is removed from the molding device 1, and after hardening of the slurry, the molding pipe 8 is formed from the cured product.
(Note that the molding tube 8 may be configured as a split mold, etc.), and the jig 10 is further removed if necessary (note that
When removing the jig 10 in this way, the jig 10 is previously removed.
It is preferable to apply a release agent on the surface).

Here, the following composition is preferable as the composition of the above-mentioned slurry (where% represents% by weight). Silicate 15 to 66%, more preferably 30 to 60% (wt%, the same applies hereinafter) Kaolin 0 to 28%, more preferably 5 to 20% Water soluble magnesium salt 0 to 1%, more preferably 0 to 0. 8% silicofluoride salt 2 to 20%, more preferably 0 to 15% metasilicate 2 to 58%, more preferably 3 to 30% dicalcium silicate 0 to 20%, more preferably 3 to 15% calcium silicate 0-10%, more preferably 0.5-5% Portland cement 0-10%, more preferably 0.5-5% Surfactant 0.1-2%, more preferably 0.1-1%. Water 0-20%, more preferably 5-15%

In this case, sodium silicate is used as the silicate, magnesium chloride is used as the water-soluble magnesium salt, sodium silicofluoride is used as the silicofluoride salt, sodium metasilicate is used as the metasilicate, and dicalcium silicate is Nippon Heavy Chemical Industry Co., Ltd. Suitable examples include JMC powder manufactured by Co., Ltd., calcium silicate manufactured by Nippon Kagaku Kogyo Co., Ltd., and anionic surfactant such as sodium lauryl sulfate as a surfactant. If necessary, an inorganic or organic filler may be added to the above composition.

Further, the foaming involves entraining air of the slurry having the above composition, and in this case, the foaming has a slurry density of 0.6 to 0.9 g / cm ³ , particularly 0.65 to 0.85.
It is preferable to entrain air so as to obtain g / cm ³ (the density of the slurry having the above composition is about 1.4 g / cm ^{3 in the} non-foamed state). If the density of the foamed slurry is lower than 0.6 g / cm ³ , it will be difficult to penetrate into the narrow gap, and if it is higher than 0.9 g / cm ³ , the fluidity will be too good and it will be difficult to maintain the shape during molding. May be.

The length of the molding pipe 8 is 0.3 m or more, particularly 1 m or more, and about 2 m can be used. The gap between the molding tube 8 and the jig 10 can be variously selected according to the purpose, but is usually 5 to 20 mm. Further, the pressing force applied to the slurry by the pressing piston 3 is not limited, but is usually 2 kg / cm ² or more, especially ^{2 to 3} kg /
cm ^2, and the slurry at a relatively low pressure according to the present invention also flowing at satisfactorily narrow.

Curing after molding may be carried out by allowing it to stand at room temperature for 1 to 5 hours. In this case, the slurry density should be 0.6 to 0.
By setting it to 9 g / cm ³ , there is substantially no movement of bubbles when left to stand, and therefore the bubbles are cured without being unevenly distributed. A homogeneous cured product (inorganic silicate foam cylinder) is obtained.

The molding pipe 8 and the jig 10 are made of steel,
It can be formed of an appropriate material such as metal such as stainless steel or plastic, but a vinyl chloride resin tube or the like is used as the jig 10, and the jig is integrated with the inorganic silicate foam cylinder even after molding and curing. By doing so, a refractory vinyl chloride resin pipe or the like can be manufactured. Further, a thin-walled steel pipe manufactured by winding a thin iron plate in a spiral shape is used as the jig 10, and the jig is integrated with the inorganic silicate foam cylindrical body even after molding and curing, thereby forming an air duct with a heat insulating material. Can be manufactured.

According to the present invention, since the inorganic silicate foam slurry as described above is used, the slurry is excellent in fluidity and shape retention, so that a long molding pipe arranged horizontally is used. Even if it is easy to mold, there is no need to stand a long molding pipe to perform molding, and it flows well even at relatively low pressure, so molding workability is very good and its shape is maintained at room temperature. Also, since it is easily cured, workability is also good in this respect. Therefore, it is possible to efficiently manufacture an inorganic cylinder having a length of 1 m or more and excellent in fire resistance and the like.

[0018]

EXAMPLES The present invention will be described in detail below with reference to examples, but the present invention is not limited to the following examples.

[Experimental Example 1] An inorganic silicate foam cylinder was manufactured under the following conditions using the apparatus shown in FIG. Molding tube: length 2 m, inner diameter 100 mm, material: acrylic or vinyl chloride resin jig: length 2 m, outer diameter 89 mm, material: slurry pressing force by metal tube pressing piston: 2 kg / cm ² ,
Cylinder pressure 157 kg Slurry composition: silicate 48%, kaolin 21%, magnesium salt 0.17%, silicofluoride salt 12%, metasilicate 7
%, Surfactant 0.3%, water 11% Density: 0.7 to 0.8 Curing condition: Room temperature curing

After molding and curing, the molding tube and jig were removed to obtain an inorganic silicate foam cylinder having a wall thickness of 5 mm. This cylinder was homogeneous with no uneven distribution of bubbles.

[Experimental Example 2] The same procedure as in Example 1 was carried out except that a vinyl chloride resin tube was used as a jig to obtain an inorganic silicate foam cylinder in which the vinyl chloride resin tube was integrated as an inner tube. .

[Comparative Example 1] The slurry viscosity was 0.5 g / c.
The same operation as in Example 1 was carried out except that m ³ was used. The obtained cylinder is a part that is not injected into the inside of the product (void)
Was found.

[Comparative Example 2] Slurry viscosity was 0.95 g /
The same operation as in Example 1 was carried out except that cm ³ was used. When the obtained cylindrical body was left standing vertically, sinking was observed in the upper molded product before curing, and a space was formed in the upper portion of 100 to 150 mm.

[0024]

EFFECTS OF THE INVENTION According to the present invention, a long inorganic refractory tube having a length of 1 m or more can be easily manufactured with good workability.

[Brief description of drawings]

FIG. 1 is a schematic sectional view showing an example of an apparatus used for carrying out the present invention.

[Explanation of symbols]

1 molding equipment 3 Pressing piston 5 Raw material supply room 8 Molding tube 10 jigs

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Shinohara             1-4-16 Nihonbashi Bakurocho, Chuo-ku, Tokyo               Fujimori Industry Co., Ltd.

Claims (2)

[Claims] 1. A molding device having a length of 1 m or more horizontally arranged in a molding device in which a pressing piston is slidably arranged at one end side and a raw material supply chamber is formed at the other end side of the pressing piston. A tube or columnar jig having a smaller diameter than the pipe is inserted into the molding pipe concentrically with connecting one end of the pipe, and the self-curing inorganic silicate foam slurry is introduced into the raw material supply chamber. After being supplied, the slurry is pressed by the piston to fill the space between the molding pipe and the jig in a tubular shape, and then the slurry is hardened. A method for producing an inorganic silicate foam cylinder, which comprises removing the inorganic silicate foam from a cylindrical cured inorganic silicate foam. 2. The method according to claim 1, wherein after the slurry is hardened, the molding pipe is removed from the cylindrical hardened inorganic silicate foam, and the jig is integrated with the foam. A method for producing an inorganic silicate foam cylinder, which is characterized by holding the same.