JPS6128455B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing steel fibers used, for example, in steel fiber reinforced concrete.

Steel fiber reinforced concrete is a mixture of oriented steel fibers in cocrete, and compared to ordinary concrete, it has better cracking resistance, toughness, tensile strength, bending strength, shear strength, heat resistance, resistance to freeze-thaw action, and surface resistance. It has been attracting attention in recent years because of its excellent performance such as resistance to deterioration. However, there are problems in that the mixed steel fibers are difficult to mass produce and the manufacturing cost is high.

There are three types of conventional steel fiber manufacturing methods:
The first cutting fiber method is to cut rolled and drawn steel wire into a predetermined length using a cutting blade, and the steel wire must be plastically worked to the thickness of the steel fiber used to manufacture the steel wire. The process is extremely long. In addition, the second shear fiber method involves shearing a cold-rolled thin steel plate with a shearing blade, and the thin steel plate can only be sheared one by one. A third method of cutting fibers involves cutting a steel plate or block with a rotating cutting blade, ie, a flat milling blade, which also yields only one steel fiber at a time.

In view of such conventional methods, an object of the present invention is to provide a method for manufacturing steel fibers that can simply and easily mass-produce steel fibers of a required length and reduce manufacturing costs. The feature is that a longitudinal protrusion and a groove crossing the protrusion are formed on the surface of the material, and the protrusion of the material is cut into a thin line with a cutting blade at a point.

Embodiments of the present invention will be described below with reference to the drawings.

In the first embodiment shown in FIGS. 1 and 2,
1 is a round or square linear material, 2 is a first processing tool,
Reference numeral 3 indicates a second processing tool, 4 indicates a third processing tool, and 7 indicates a manufactured steel fiber.

FIG. 1 shows a plastic working process in which a longitudinal protrusion 8 and a groove 14 crossing it are formed on the surface of the material 1, and the first processing tool 2 is, as shown in FIGS. 1A and B, This hole die has serrated protrusions 9 on its inner periphery, and by passing the material 1 through it, a large number of triangular protrusions 8 continuous in the longitudinal direction (axial direction) are formed on its surface. The material is passed through the first processing tool 2 by a conventional rolling method, such as extrusion or drawing, and is similar to wire drawing.

The first processing tool 2 is not limited to a hole die, but may also be a roller die having a plurality of triangular grooves 10 on the outer periphery, as shown in FIG. Further, the shape of the valley or groove 10 of the protrusion 9 of the first processing tool 2, that is, the cross-sectional shape of the protrusion 8 is not limited to a triangle, but may be a square, a semicircle, or the like.

The second processing tool 3 is a grooving tool, and as shown in FIG. By passing the material 1 having the protruding stripes 8 through it, circumferential grooves 14 are formed on its surface. This groove 14 crosses the protrusion 8 and has approximately the same depth as the valley bottom 8a.

The groove formation by the second processing tool 3 is to set the length of the steel fiber 7 to be manufactured, and the diameter of the roller or the number of groove cutting blades 15 on the roller can be arbitrarily selected. , the steel fibers 7 can be formed to a required length. Further, this second processing tool 3 is placed in front of the first processing tool 2, and the protrusion 8 is attached to the material 1.
Grooving may be performed before forming (however,
The groove 14 is not filled in by processing with the first processing tool 2. ) That is, in the plastic working process, as long as the protrusion 8 and the groove 14 crossing it are formed at the end of the plastic working process, either the protrusion 8 or the groove 14 crossing the protrusion 8 may be formed.
If a material 1 (for example, a triangular or square bar whose corner portion becomes the protrusion 8) is used, only the second working tool 3 may be used in the plastic working step.

Before or after processing with this second processing tool 3, the fourth
A deforming roll 11 as shown in the figure may be arranged. This deformed roll 11 has irregularities on the outer periphery, and the protrusions 8 are formed with irregularities to give the cut steel fibers 7 a deformation 12 that is not linear, thereby increasing the adhesion strength with concrete. . This defamation 12 is not limited to a hook shape, but may have a different diameter or other shapes. This deformation roll 11 is preferably placed in front of the second processing tool 3, and when placed in the rear, the groove 14 is not filled.

The material 1 having the protrusions 8 and the grooves 14 is
As shown in the figure, it is moved to the cutting process. The third tool 4 is a ring-shaped cutting blade, and has a blade portion 3a having a diameter that is the same as or slightly larger than the diameter of the root 8a of the material 1. The protruding portion 8 is continuously cut from its root portion, and the thin wire-shaped steel fiber 7 having a substantially triangular cross section is cut to a certain length. A large number of protrusions 8 in the circumferential direction of the material 1 are cut out simultaneously and in the same shape by the third processing tool 4.

After the cutting process, the material 1 has a circular or second surface.
It is in a slightly uneven state as shown in Figure B, and this is supplied to the plastic working process again, and a die with a smaller diameter than the die of the first working tool 2 and a second die are formed.
pass through the processing tool 3 to form the protrusion 8 and the groove 14;
Further, steel fibers 7 are formed in the same manner as described above. By repeating this process, a large number of identical or irregularly shaped steel fibers 7 and the thin wire rod that ultimately remain are obtained several times from the thick rod-shaped material 1. The plastic working process and the cutting process may be performed independently or consecutively, and if they are performed continuously, both processes are treated as one block and multiple blocks are connected in series to obtain the final fine wire material. It is also possible to perform continuous processing up to

FIG. 5 shows a second embodiment of the present invention, in which the material 1 is a flat plate or a block, the first processing tool 2' is a pair of upper and lower roller dies having triangular protrusions 9 on the outer periphery; The second processing tool 3 is a pair of upper and lower rollers having two groove cutting blades 15, and the third processing tool 4' is formed of a pair of upper and lower knives (cutting blades).

In the plastic working process shown in FIGS. 5A and 5B, a large number of protrusions 8 are formed in the longitudinal direction (transfer direction) on the upper and lower surfaces of the flat plate material 1' while rolling it with a roller die, and then at regular intervals. In the cutting process shown in FIGS. 5A and 5C, all the protrusions 8 are cut with a knife, and the grooves 14 are perpendicular to the longitudinal direction with the groove cutting blade 15. Cut out the long steel fiber 7.

In this second embodiment, since a plurality of steel fibers 7 can be cut from each side of the material 1', the flat material 1'
It is possible to cut the steel fibers 7 from only one side of the block material, or to simultaneously cut the steel fibers from three or more polygonal faces of the block material.

According to the present invention described in detail above, the longitudinal protrusion 8 and the groove 14 crossing the protrusion 8 are formed on the surface of the material 1, such as a linear or flat plate, by plastic working, Since the steel fibers 7 are produced by cutting the protrusions 8 into thin lines with the cutting blade 3, even ultra-fine fibers can be manufactured very simply and easily. Since the steel fibers can be formed in large quantities, it is possible to mass-produce steel fibers of the required length, and manufacturing costs can be reduced.

[Brief explanation of the drawing]

1 and 2 show a first embodiment of the present invention, and FIG. 1A is a cross-sectional side view of the plastic working process;
Figure 1B is a cross-sectional front view of the first processing tool part, Figure 1C is a cross-sectional front view of the second processing tool part, and Figures 2A and B.
are respectively a cross-sectional side view and a cross-sectional front view of the cutting process, and the third
The figure shows a cross-sectional front view showing another example of the first processing tool, FIG. 4 shows a cross-sectional side view showing one example of the defamation roller, and FIG. 5 shows a second embodiment of the present invention. 5A is a cross-sectional side view of the whole, FIG. 5B is a cross-sectional front view of the first processing tool portion, and FIG. 5C is a cross-sectional front view of the third processing tool portion. 1...Material, 2...First processing tool, 3...Second processing tool (grooving tool), 4...Third processing tool (cutting blade), 7
...Steel fiber, 8...Protrusion, 14...Groove.

Claims (1)

[Claims] 1. A steel characterized in that a longitudinal protrusion 8 and a groove 14 crossing the strip 8 are formed on the surface of the material 1, and the strip 8 of the material 1 is cut into a thin line shape with a cutting blade 3. Fiber manufacturing method.