JPH05237825A - Manufacture of bar material having open section - Google Patents

Abstract

PURPOSE:To provide a continuous manufacture of a bar material which can make air-dried specific gravity low by making use of lightweight aggregate as a material and has moreover a smooth outer surface and thin open section. CONSTITUTION:Mortar containing at least a binder and aggregate is cut down continuously and at a fixed thickness on a conveyor 12 for which a belt permeable to liquid is used, the cut down mortar is dehydrated gradually by a sucking mechanism 15 provided on the bottom part of the belt 11 permeable to liquid, the dehydrated mortar is put between the belt permeable to liquid and an upper belt and continuous pressure molding, is performed by passing the mortar through a gap having a thin open sectional form which is to be manufactured under this state.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for continuously manufacturing a bar material having a groove-shaped, Z-shaped or chevron-shaped cross section by using, for example, lightweight cement.

[0002]

2. Description of the Related Art Conventionally, in the field of iron and steel, an extrusion molding method has been mainly used for continuously producing a bar material having a thin open section such as a groove shape, a Z shape, and a mountain shape.

[0003]

However, a lightweight cement mortar using shirasu balloon, fly ash balloon, perlite or other lightweight aggregate is used to produce a thin open-section bar material by the extrusion molding method. In this case, it is difficult to reduce the amount of the lightweight aggregate mixed due to the problem of moldability, and it is difficult to reduce the weight so that the air-dry specific gravity is 1.2 or less. Even if the amount is small, there is a drawback that rough skin occurs due to friction with the wall surface during extrusion. The present invention has been made in view of the above circumstances, and it is possible to reduce the air-dry specific gravity (for example, 0.4 to 1.4) by using a lightweight aggregate as a mortar material, and yet to obtain a smooth outer surface. An object of the present invention is to provide a continuous manufacturing method of a thin-walled open-section bar material having a surface.

[0004]

A method according to the above-mentioned object.
The method for manufacturing a thin-walled open-section rod material according to the description, a mortar containing at least a binder and an aggregate is continuously cut out at a predetermined thickness on a conveyor using a liquid-permeable belt, and the cut-out mortar is the liquid-permeable belt. Is gradually dehydrated by a suction mechanism provided at the bottom of the device, the dehydrated mortar is sandwiched between the liquid-permeable belt and the upper belt, and a gap having a thin open cross-sectional shape to be manufactured in this state is provided. It is configured such that the mortar is continuously pressure-molded. Here, the liquid permeable belt refers to a belt that allows only water to pass without passing a mortar material, and corresponds to, for example, a filter cloth belt.

[0005]

The mortar is cut to a predetermined thickness on a conveyor using a liquid permeable belt, and dehydrated to a certain degree by a dehydrating mechanism provided below the liquid permeable belt. Since the mortar is sandwiched between the belts and is continuously pressure-molded through the gap having the thin open cross-sectional shape to be molded, a bar material having a high packing density can be manufactured. Since the pressure molding is continuously carried out in a state of being sandwiched between the upper belt and the lower liquid permeable belt which are simultaneously moving, the surface of the product is not roughened and blow holes are less likely to occur.

[0006]

EXAMPLES Next, examples embodying the present invention will be described. Here, FIG. 1 is a side view of a manufacturing apparatus to which a method for manufacturing a thin-walled open-section rod according to an embodiment of the present invention is applied, and FIG.
Is a sectional view taken along the line AA in FIG. 1, and FIGS. 3 and 4 are sectional views of the bar.

First, as shown in FIGS. 1 and 2, the manufacturing apparatus 10 includes a filter cloth belt 11 which is an example of a liquid permeable belt.
, A mortar storage hopper 14 for storing the light mortar 13 and gradually cutting the light mortar 13 from the lower part, and a vacuum tank which is a component of the dehydration mechanism arranged under the filter cloth belt 11. 15,
Pressurization mechanism 16 for pressing the mortar 13 being conveyed from above
And a guide plate 17 having a predetermined cross section for receiving the pressed mortar 13. Less than,
These will be described in detail.

The filter cloth belt 11 is made of a strong synthetic fiber (for example, nylon, tetron, aramid fiber) or a natural fiber (for example, cotton, hemp) having sufficient strength. Moisture contained in is designed to pass through. In addition, the filter cloth belt 1
A feed roll 19 that feeds 1 is provided in the front part, and the filter cloth belt 11 is fed at a predetermined speed by a deceleration motor (not shown) that drives the feed roll 19.

The mortar storage hopper 14 has a substantially rectangular cross section and does not have a bottom plate. The mortar storage hopper 14 stores the light mortar 13 charged from the upper portion and cuts it out on the lower filter cloth belt 11 with a predetermined thickness. .. The dehydration mechanism comprises a vacuum tank 15 provided at the bottom of the filter cloth belt 11 and having a large number of small holes on the ceiling surface, and a vacuum pump (not shown) connected to the vacuum tank 15. It absorbs the moisture of the mortar on the cloth belt 11.

Further, in the case of manufacturing the bar member 20 having an open cross-sectional shape shown in FIG. 3 (the described dimensions are mm), the pressing mechanism 16 has an upper roll 21 having a shape as shown in FIG.
And an upper belt 22 arranged between the upper roll 21 and the mortar 13, and the upper rolls with springs 23, 24.
Cylinder 25 that is pressed via the upper support member 2
And 6 are provided. Shaft 2 of the upper roll 21
7, bearings 28 and 29 are provided, rotatably attached to housings 31 and 31 that move up and down along guides, and the housings 30 and 31 are connected to springs 23 and 24 to generate hydraulic or pneumatic pressure. It is adapted to be pressed downward by the cylinder 25. The upper belt 22 is made of a synthetic fiber, a natural fiber, a flexible synthetic resin or a rubber belt having sufficient strength and elasticity to some extent, and a cylindrical roll 32 on the front side in the traveling direction.
And the mortar 13 is guided between the upper roll 21 and the lower upper corrugated guide plate 17. A drive motor may be provided on the roll 32, or the roll 32 may be freely rotated and moved by friction with the upper belt 22.

Similar to the upper roll 21, the void plate 17 has various shapes according to the cross-sectional shape of the bar to be formed. However, as shown in FIG. 1, the front side is flat, As shown in FIG. 2, the upper roll 21 has a gradual depression, and has the same cross-sectional shape as the bar material to be molded and retains the shape as it is until a predetermined length in the traveling direction.
It is also possible to use the inside of the guide plate 17 as a space, to form a large number of small holes on the surface, and to suction by vacuum, which makes it possible to further dehydrate the mortar. Further, since the upper belt 22 and the filter cloth belt 11 pass through the surfaces of the upper roll 21 and the guide plate 17, the upper roll 21 and the guide plate 17 are made of metal or ceramic having abrasion resistance and sufficient strength. Then, a conveyor 33 connected to the conveyor 12 is provided, and a conveyor cutting machine (not shown) that moves in synchronization with the conveyor 33 and cuts the bar material 20 on the conveyor 33 into a predetermined length is provided. It is provided.

Next, the rod 2 is manufactured by the manufacturing apparatus 10.
More specifically, the method for producing 0 will be described in detail in the mortar storage hopper 14 in advance with lightweight aggregate, cement,
Mortar 13 mixed with water and an appropriate amount of reinforcing fibers as needed is put therein, and the conveyor 12 is driven to cut out onto the filter cloth belt 11. The thickness of the cutout is determined by changing the height of the gate provided on the outlet side upper portion of the mortar storage hopper 14. The mortar 13 cut out to a predetermined thickness is transferred from the vacuum tank 15 provided on the lower surface of the filter cloth belt 11 while being sucked and dehydrated. The length of this suction dehydration section is 1 to 1
About 0 m is preferable. The mortar that has been sucked and dehydrated and flattened is then subjected to the upper belt 22 and the lower filter cloth belt 1.
It is sandwiched by 1 and gradually bent, and has a predetermined cross-sectional shape. Further, a pressure of 0 to 100 kg / cm ² is applied by the upper roll 21 and the guide plate 17, and it is molded and dehydrated to a required thickness. After this, the conveyor 3 to be connected
Moving to 3, the bar 20 is cut into a predetermined length, dried and cured to be a bar 20 having a predetermined strength, and air-flow dried to obtain a product.

In Table 1, the weights of the raw materials of Example 1 in which the bar member 20 having the cross-sectional shape shown in FIG. 3 is manufactured and Example 2 in which the bar member 34 having the cross-sectional shape shown in FIG. 4 (dimension is mm) is manufactured. Shows the ratio,
Table 2 shows the conditions and the strength of the product, but the present invention is not limited to the numerical values of this example.

[0014]

[Table 1]

[0015]

[Table 2]

As is clear from Table 2, it is understood that a bar material having sufficient strength can be manufactured, and the specific gravity becomes smaller if the amount of the lightweight aggregate is increased. It should be noted that, when accurately manufacturing a bar material having a predetermined shape, it is possible to accurately control the amount of the raw material to be cut out, but when it is necessary to manufacture the material more accurately, after molding, it is appropriately performed. This is done by cutting. Further, when the rod member 34 is formed, it is difficult to form it if the side walls of the groove are kept parallel.
It is preferable to perform the molding with a taper of about 5 degrees.

Although Portland cement was used as the binder in the above-mentioned examples, the present invention can be applied to other cements or binders. Although shirasu balloon was used as the lightweight aggregate in the above-mentioned examples, the present invention is also applicable to fly ash balloons, shirasu balloons, perlite, and other natural or artificial aggregates. Further, in the above examples, 350 denier vinylon fiber (length about 10 to 12 mm) was used as the reinforcing fiber, but other synthetic resin fiber, glass fiber, carbon fiber, pitch fiber or other mineral fiber, depending on the case May be a metal fiber.

[0018]

As is apparent from the above description, the method for manufacturing a thin-walled open-section bar according to the first aspect of the present invention is to provide the mortar on the lower portion of the liquid permeable belt after cutting the mortar into the liquid permeable belt. Since it is dehydrated to some extent by the dehydration mechanism and then pressure-molded, a product having a high density and sufficient strength can be continuously produced.

[Brief description of drawings]

FIG. 1 is a schematic side view of an apparatus to which a method for manufacturing a thin-walled open-section rod according to an embodiment of the present invention is applied.

2 is a sectional view taken along the line AA in FIG.

FIG. 3 is a sectional view of a bar.

FIG. 4 is a sectional view of a bar.

[Explanation of symbols]

 10 Manufacturing Equipment 11 Filter Cloth Belt 12 Conveyor 13 Mortar 14 Mortar Storage Hopper 15 Vacuum Tank 16 Pressurizing Mechanism 17 Guide Plate 18 Reversing Roll 19 Feed Roll 20 Bar 21 Upper Roll 22 Upper Belt 23 Spring 24 Spring 25 Cylinder 26 Supporting Member 27 Shaft 28 Bearing 29 Boaring 30 Housing 31 Housing 32 Roll 33 Conveyor 34 Bar

Claims (1)

[Claims] 1. A mortar containing at least a binder and an aggregate is continuously cut into a predetermined thickness on a conveyor using a liquid permeable belt, and the cut mortar is suctioned at the bottom of the liquid permeable belt. The mortar is gradually dehydrated by a mechanism, the dehydrated mortar is sandwiched between the liquid-permeable belt and the upper belt, and the mortar is continuously pressure-molded through a gap having a thin open cross-sectional shape to be manufactured in this state. A method for manufacturing a thin-walled open-section bar material, comprising: