JP3525192B2 - Flow-on papermaking method for fiber reinforced cement board - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The invention of the present application relates to a flow-on papermaking method for fiber-reinforced cement boards.
More specifically, the invention of this application relates to a flow-on papermaking method for a fiber-reinforced cement board, which is capable of favorably dewatering both end portions while defining a width dimension.

[0002]

2. Description of the Related Art Fiber-reinforced cement boards are widely used for exterior materials such as outer wall materials and roof materials. As a manufacturing technique for this fiber-reinforced cement board, for example, the flow-on papermaking method shown in FIG. 6 is known.

That is, cement and a cement composition containing pulp and reinforcing fibers such as chemical fibers such as vinylon and polypropylene as main components, and silica and various additive components appropriately mixed therein are dispersed in water to obtain a solid content. Concentration 25-6
A slurry having a relatively high concentration or a high concentration prepared to about 5% is supplied from the flow box (1) onto the water permeable sheet (2). The water permeable sheet (2) is made of a non-woven fabric such as woven cloth or felt, has water permeability, and is formed into an endless continuous body.
And, it is circulated around the driven roll (4).

The slurry supplied onto the water permeable sheet (2) is dewatered while being spread and carried on the water permeable sheet (2). The dehydration consists of a continuous process of natural dehydration and subsequent vacuum dehydration.

Natural dehydration zone (5) where natural dehydration is performed
A natural dehydration box (6) for draining water containing solids after dehydration is disposed immediately below the water-permeable sheet (2), and the slurry spread on the water-permeable sheet (2). A vibration leveling device (7) is provided in order to eliminate the thickness distribution. From the vibration leveling device (7), vibration is applied to the slurry from the surface side to perform leveling.

Next, the slurry is conveyed to the suction zone (8) where decompression dehydration is performed. In the suction zone (8), a suction box (9) for decompressing and draining is arranged.

Through the above steps, the slurry is made into a sheet-like fiber-reinforced cement board having a predetermined thickness and a predetermined water content on the water-permeable sheet (2).

[0008]

On the other hand, in the flow-on papermaking method for such a fiber-reinforced cement board, there have been found problems to be solved thereafter.

The slurry supplied and spread on the water permeable sheet (2) is leveled by the vibration leveling device (7) in the natural dewatering zone (5) and spreads into a sheet shape. It is highly concentrated or has fluidity even at high concentration, and it spreads to both sides due to vibration applied from the surface side, and the dimension in the width direction is not fixed. As a means for solving this, it is conceivable to extend a width regulation guide plate that regulates the width of the slurry, which is trying to spread to both sides, from both end portions of the flow box (1) in the slurry conveyance direction. .

However, when the width-regulating guide plate is arranged and the leveling is tried in the natural dehydration zone (5), the width of the slurry is determined accurately by the width-regulating guide plate. Then, it was confirmed that the material would rise along both sides of the slurry along the width-regulating guide plates. It is considered that this is because the movement of the slurry, which tends to spread to both sides due to the vibration, is restricted by the width regulation guide plate, and a material pool is formed along the width regulation guide plate.

The portion where the material rises cannot be sufficiently dehydrated even in the suction zone (8) for dehydration under reduced pressure in the subsequent stage, resulting in insufficient dehydration, that is, excessive water content. As a result, the sheet-shaped fiber-reinforced cement board thus made up is cut into a predetermined size, and when it is adsorbed and moved to the next step, the rising part adheres to the adsorber, causing a suction error. Becomes

The invention of this application has been made in view of the circumstances as described above, and the flow-on papermaking of a fiber-reinforced cement board capable of satisfactorily dehydrating both end portions while defining the width dimension. Providing a method is an issue to be solved.

[0013]

Means for Solving the Problems In order to solve the above-mentioned problems, the invention of the present application has a solid content concentration of 25 to 65 obtained by dispersing a cement composition containing cement and reinforcing fibers as main components in water. % Relatively high concentration or high concentration slurry is supplied from the flow box onto the water permeable sheet that moves around, and while the developed slurry is conveyed by the water permeable sheet, it is vibrated and leveled in the natural dehydration zone from the surface side. After leveling by adding vibration, depressurized dewatering is performed in a suction zone that is continuous with the natural dewatering zone, and when making a sheet-shaped fiber-reinforced cement plate,
A vibration leveling device is installed between the width regulation guide plates extending from both ends of the flow box in the slurry conveying direction to perform leveling, and auxiliary vibration leveling that adds weaker vibration to the slurry than the vibration applied by the vibration leveling device. The device is arranged in the suction zone, and this auxiliary vibration leveling device applies weak vibration from the surface side,
A flow-on papermaking method for a fiber-reinforced cement board (claim 1), characterized in that the rising portions of both side ends of the sheet-shaped slurry spread on a water-permeable sheet are corrected.

Further, the invention of this application is such that a relatively high concentration or a high concentration slurry having a solid content concentration of 25 to 65% obtained by dispersing a cement composition containing cement and reinforcing fibers as main components in water is flow box. It is continuously fed to the natural dewatering zone after leveling by applying vibration from the surface side by the vibration leveling device in the natural dewatering zone while conveying the slurry that is supplied and spread on the water permeable sheet that moves around from the water permeable sheet. When performing dewatering under reduced pressure in the suction zone and making sheet-shaped fiber-reinforced cement plates into paper, leveling is performed by arranging a vibration leveling device between the width-regulating guide plates extending in the slurry transport direction from both ends of the flow box. In addition to the above, in the suction zone, on both side edges of the sheet-like slurry spread on the water-permeable sheet. To dispose the air nozzle blows air from the air nozzle side end portions of the sheet-like slurry flow on papermaking method of the fiber-reinforced cement board, characterized in that to correct Crawling portion (claim 2)
Will also be provided.

Hereinafter, the flow-on papermaking method of the fiber-reinforced cement board of the invention of this application will be described in more detail with reference to the accompanying drawings.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION FIG.
FIG. 1 is a plan view, an enlarged cross-sectional view and a cross-sectional view schematically showing an embodiment of a flow-on papermaking method for a fiber-reinforced cement plate of the invention of this application.

For example, as shown in FIGS. 1A and 1B, the flow-on papermaking method of the fiber-reinforced cement board of the invention of this application is the same as the flow-on papermaking method of the fiber-reinforced cement board shown in FIG. It is assumed.

Further, in the embodiment shown in FIGS. 1A and 1B, the width regulating guide plates 11 are extended from both side ends of the flow box 1 in the transport direction of the slurry 10. Then, the vibration leveling device (7) is arranged between the width regulation guide plates (11) to perform leveling. There is no particular limitation on the configuration and structure of the vibration leveling device (7).
As shown in <a> and <b>, for example, one including a vibration motor (7a) and a vibration plate (7b) to which the vibration is transmitted is exemplified.

The slurry (7) formed by the vibration leveling device (7) is provided between the width-regulating guide plates (11) extending in the conveying direction of the slurry (10) from both ends of the flow box (1). By the leveling of 10), as described above, the width dimension of the slurry (10) spread on the water-permeable sheet (2) in the form of a sheet can be set to a constant value. A rising portion (12) is formed along the width regulation guide plate (11).

Therefore, in the flow-on papermaking method of the fiber-reinforced cement board of the invention of the present application, one of means for correcting such a rising portion (12) is shown in FIG.
As shown in a><b>, the vibration leveling device (7)
An auxiliary vibration leveling device (13) that applies a weaker vibration to the slurry (10) than the vibration that is added by the auxiliary vibration leveling device (13) is provided in the suction zone (8).
Thus, a weak vibration is applied to the slurry (10) from the surface side to correct the rising portions (12) formed at both end portions of the sheet-shaped slurry (10).

The configuration and structure of the auxiliary vibration leveling device (13) are not particularly limited as in the vibration leveling device (7). For example, a vibration motor (13a) and a diaphragm (13b) to which the vibration is transmitted. The one provided with is exemplified. Also, various methods can be considered for weakening the vibration applied by the auxiliary vibration leveling device (13) as compared with the vibration leveling device. For example, the amplitude and weight of the auxiliary vibration leveling device (13) (for example, the weight of the diaphragm). May be smaller than the vibration leveling device (7).

Such an auxiliary vibration leveling device (1
By disposing 3) in the suction zone (8),
The rising portion (12) is leveled without adversely affecting other regions, and both side ends of the slurry (10) are sufficiently dehydrated in the suction zone (8). The sheet-shaped fiber-reinforced cement board (14) that has been made up is cut into a predetermined size, and then there is no rising portion (12) when adsorbing and moving to the next step. Adhesion of non-dehydrated material to the adsorbing device Does not occur and no adsorption error occurs.

Regarding the embodiment shown in FIGS. 1A and 1B, as shown in FIGS. 2A and 2B, the width (w) of the auxiliary vibration leveling device (13) is set to the vibration leveling. If it is larger than the width (W) of the device (7), it is considered to be more effective in correcting the rising portion (12).

3A and 3B are a plan view, an enlarged sectional view and a sectional view, respectively, schematically showing another embodiment of the flow-on papermaking method for a fiber-reinforced cement board of the invention of this application. It is a figure.

In the flow-on papermaking method of the fiber-reinforced cement board of the invention of this application, as in the embodiment shown in FIG. 3 <a><b>, FIG. 1 <a><b> and FIG. 2 <a><B>
In place of the auxiliary vibration leveling device (13) shown in FIG. 1, in the suction zone (8), air nozzles (15) are provided above both side ends of the sheet-like slurry (10) spread on the water-permeable sheet (2). Can be provided. The leveling is performed by arranging the vibration leveling device (7) between the width regulating guide plates (11) extending from the both ends of the flow box (1) in the transport direction of the slurry (10). There is no difference from the embodiment shown in 1 <a><b> and FIG. 2 <a><b>.

In the embodiment shown in FIGS. 3A and 3B, air (16) is blown from the air nozzle (15) to both side ends of the sheet-like slurry, and after leveling, both side ends of the slurry (10). Then, the rising portion (12) formed along the width regulation guide plate (11) is corrected. In this way, the air (16) from the air nozzle (15)
The sprayed part (12) can even out the rising part (12) without adversely affecting other regions, and can sufficiently dehydrate both side ends of the slurry (10) in the suction zone (8). it can. The sheet-shaped fiber-reinforced cement board (14) that has been made up is cut into pieces of a predetermined size and then lifted up (12) at the time of adsorption movement for carrying to the next step.
No longer exists, no undehydrated material adheres to the adsorption device, and no adsorption error occurs.

Such an air nozzle (15) is used in the flow-on papermaking method of the fiber-reinforced cement board of the invention of the present application, as shown in FIGS. 1 <a><b> and 2 <a><b>. It is also possible to incorporate it into the form. In that case, FIG.
As shown in <a> and <b>, the air nozzle (15)
Is disposed above both side ends of the sheet-shaped slurry (10) spread on the water-permeable sheet (2), and is located behind the auxiliary vibration leveling device (13) in the transport direction of the slurry (10). It may be arranged. Such an auxiliary vibration leveling device (13) and an air nozzle (1
The combination with 5) is considered to be more effective in correcting the rising portion (12).

5A and 5B are a plan view and an enlarged cross-sectional view of a main part schematically showing another embodiment of the flow-on papermaking method for the fiber-reinforced cement board of the invention of the present application, respectively. FIG.

In the embodiment shown in FIG. 5 <a><b>, the air nozzle (15) in the embodiment shown in FIG. 4 <a><b> is replaced and the air is supplied onto the water permeable sheet (2). And is effective in suppressing the thickness distribution of the developed slurry (10) and the movement on the water permeable sheet (2).
Further, a pressing member (17), which is also effective for eliminating pressure loss during vacuum dewatering in the suction zone (8), is arranged so as to contact the surface of the slurry (2), and this pressing member (17) is also provided. Is the same as the water permeable sheet (2),
It is possible to move around. In this case, it is conceivable that the vibrations of the vibration leveling device (7) and the auxiliary vibration leveling device (13) are applied to the slurry (10) via the pressing member (17). The pressing member (17) can also correct the rising portion (12) in combination with the auxiliary vibration leveling device (13).

Next, examples and comparative examples of the flow-on papermaking method for the fiber-reinforced cement plate of the invention of this application will be shown.

[0031]

EXAMPLES (Examples 1 and 2, Comparative Examples 1 to 3) FIG.
The embodiment shown in <a> and <b> (that is, the width regulating guide plates (11) are extended from both side ends of the flow box (1) in the transport direction of the slurry (10), and the vibration leveling device ( 7) is provided for leveling, and an auxiliary vibration leveling device (13) is provided in the suction zone (8), which is weaker than the vibration applied by the vibration leveling device (7) from the auxiliary leveling device (13). Vibration is applied to the slurry (10) (Example 1)), and the embodiment shown in FIG. 3 <a><b> (ie, from the both side ends of the flow box (1) in the transport direction of the slurry (10). A width regulation guide plate (11) is extended, and a vibration leveling device (7) is disposed between them to perform leveling, and in the suction zone (8), the slurry (1
0) is provided with air nozzles (15) above both ends, and air (16) is sprayed from the air nozzles (15) to both ends of the slurry (10) (Example 2)).
The example shown in FIG. 6 in which the width regulation guide plate (11) is not provided (Comparative Example 1), the vibration leveling device (7) in Example 1 is removed, and the auxiliary vibration leveling device (13) is removed.
Comparison was made with an example (Comparative Example 2) in which only one was provided and an example (Comparative Example 3) in which the auxiliary vibration leveling device (13) in Comparative Example 2 was replaced with a vibration leveling device (7).

The composition and composition of the cement composition were 50 parts by weight of ordinary Portland cement, 45 parts by weight of silica, and 5 parts by weight of pulp, which were dispersed in water to prepare a slurry (10) having a solid content concentration of 40%. . The water-permeable sheet (2) was conveyed at a speed of 10 m / min, and in the suction zone (8), the slurry (10) was vacuumed at 40 kPa.
Was dehydrated under reduced pressure.

The vibration conditions of the vibration leveling device (7) and the auxiliary vibration leveling device (13) are as follows.

Vibration leveling device (7) Amplitude 0.25 mm Vibration frequency 3600 rpm Weight 30 kg Vibration plate (7b) material SUS304 ・ Auxiliary vibration leveling device (13) Amplitude 0.2 mm Vibration frequency 3600 rpm Weight 5 kg Vibration plate (13b) material Aluminum Then, the final sheet width (the target sheet width was set to 1000 mm) of the obtained sheet-shaped fiber-reinforced cement board, the water content difference between both end portions and the central portion, and the bending strength were measured. Table 1 shows the result.

[0035]

[Table 1]

As shown in Table 1, it is confirmed that the flow-on papermaking method of the fiber-reinforced cement board of the invention of the present application can satisfactorily dewater both end portions while defining the width dimension. . From this, it is considered that the non-dehydrated material does not adhere to the adsorbing device during the adsorbing movement which is carried to the next step after being cut into the predetermined size, and the adsorption error does not occur.

It is also confirmed that the strength of the fiber-reinforced cement board manufactured by the flow-on papermaking method of the fiber-reinforced cement board of the invention of this application is superior to that of the comparative example.

Of course, the invention of this application is not limited to the above-described embodiments and examples. Raw material of cement composition and its mixture, material of water permeable sheet,
It goes without saying that various aspects are possible in details of the configuration, structure, and vibration conditions of the vibration leveling device and the auxiliary vibration leveling device.

[0039]

As described in detail above, according to the invention of this application, in the flow-on papermaking of a fiber-reinforced cement plate, the width dimension can be regulated and both side edges can be dehydrated well.

[Brief description of drawings]

1A and 1B are a plan view, an enlarged sectional view, and a sectional view, respectively, schematically showing an embodiment of a flow-on papermaking method for a fiber-reinforced cement plate of the invention of this application. is there.

2 is a diagram of <a><b>, and FIG.
FIG. 3 is a plan view, an enlarged cross-sectional view and a cross-sectional view of an essential part of the embodiment shown in FIG.

3A and 3B are a plan view, an enlarged cross-sectional view, and a cross-sectional view, respectively, schematically showing another embodiment of the flow-on papermaking method for a fiber-reinforced cement plate of the invention of this application. Is.

4A and 4B are a plan view, an enlarged cross-sectional view, and a cross-sectional view, respectively, schematically showing another embodiment of the flow-on papermaking method for a fiber-reinforced cement plate of the invention of the present application. It is a figure.

5A and 5B are a plan view, an enlarged cross-sectional view, and a cross-sectional view, respectively, schematically showing another embodiment of the flow-on papermaking method for a fiber-reinforced cement plate of the invention of this application. It is a figure.

FIG. 6 is a cross-sectional view showing an outline of a flow-on papermaking method for a fiber-reinforced cement plate.

[Explanation of symbols]

1 flow box 2 Water-permeable sheet 3 drive roll 4 Driven roll 5 Natural dehydration zone 6 natural dehydration box 7 Vibration leveling device 7a Vibration motor 7b diaphragm 8 suction zones 9 Suction box 10 slurry 11 Width regulation guide plate 12 rising part 13 Auxiliary vibration leveling device 13a Vibration motor 13b diaphragm 14 Fiber reinforced cement board 15 Air nozzle 16 air 17 Holding member

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-10-323811 (JP, A) JP-A-10-180723 (JP, A) JP-A-9-225914 (JP, A) JP-A-9- 141626 (JP, A) (58) Fields surveyed (Int.Cl. ⁷ , DB name) B28B 1/52 B28B 17/00

Claims (2)

(57) [Claims] 1. A solid content concentration of 25 to 25 obtained by dispersing a cement composition containing cement and reinforcing fibers as main components in water.
65% of relatively high concentration or high concentration slurry is supplied from the flow box onto the water permeable sheet moving around.
The slurry to be spread is conveyed by a water-permeable sheet and leveled by applying vibration from the surface side by a vibration leveling device in a natural dehydration zone, and then depressurized and dehydrated in a suction zone continuous to the natural dehydration zone to form sheet-like fibers. When making a reinforced cement plate, leveling is performed by placing a vibration leveling device between the width regulation guide plates extending in the slurry transport direction from both ends of the flow box, and it is more effective than the vibration applied by the vibration leveling device. An auxiliary vibration leveling device that adds weak vibration to the slurry is installed in the suction zone, and weak vibration is applied from the surface side by this auxiliary vibration leveling device, and the rising parts of both ends of the sheet-like slurry spread on the water-permeable sheet. -On papermaking method for fiber-reinforced cement board characterized by straightening 2. A solid content concentration of 25 to 20 obtained by dispersing a cement composition containing cement and reinforcing fibers as main components in water.
65% of relatively high concentration or high concentration slurry is supplied from the flow box onto the water permeable sheet moving around.
The slurry to be spread is conveyed by a water-permeable sheet and leveled by applying vibration from the surface side by a vibration leveling device in a natural dehydration zone, and then depressurized and dehydrated in a suction zone continuous to the natural dehydration zone to form sheet-like fibers. When paper-making a reinforced cement board, leveling is performed by arranging a vibration leveling device between the width regulation guide plates extending in the slurry transport direction from both ends of the flow box, and at the suction zone, on the water-permeable sheet. A fiber reinforced cement characterized by arranging air nozzles above both ends of the sheet-like slurry that has been spread over the sheet, and blowing air from the air nozzles to both ends of the sheet-like slurry to correct the rising portion. Flow-on papermaking method for board.