JP2016072094A - Partial heating apparatus for reinforcement material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a partial heating apparatus for a reinforcement material capable of surely providing a normal strength portion and a high strength portion by reducing a length of a strength transient portion.SOLUTION: A partial heating apparatus 1 includes heating means 10 for heating a part of a reinforcement material 2 in a length direction as a heating portion and, more preferably, includes heat conduction control means 20 for controlling heat conduction from the heating portion of the reinforcement material 2 to a neighboring portion out of the heating portion. The heating means 10 is provided correspondingly to a center side of the reinforcement material 2 in the length direction and configured to heat the heating portions at the center side of a plurality of reinforcement materials 2 which are conveyed by conveyance means 40, simultaneously for a predetermined time. As such heating means 10, a pair of heating furnaces 11 such as resistance heating furnaces, infrared heating furnaces or induction heating furnaces are provided, which are disposed at an upper side and a lower side of the reinforcement material 2. The upper heating furnace 11 is fixed on a ceiling surface of a frame 1A, and the lower heating furnace 11 is installed on the floor.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a partial heating device for reinforcing steel material.

Conventionally, a reinforcing bar structure including a main bar for a column and a main bar for a beam joined to the main bar for the column is known.
It is known to use a reinforcing bar having a normal strength portion having a predetermined strength and a high strength portion having a strength higher than the predetermined strength as the main reinforcing bar for the beam having such a reinforcing bar structure (for example, Patent Document 1). reference). In such a reinforcing bar, the normal strength part is formed on both sides in the longitudinal direction, the high strength part is formed in the center in the longitudinal direction, and when the main reinforcing bar is formed by joining with other similar reinforcing bars, Normal strength parts are joined together by welding or the like. The main bars configured for the beams are arranged so that the high-strength portion is located at the joint portion with the main bars for the column.

Utility Model Registration No. 3147699

As described in Patent Document 1, when a single reinforcing bar has a portion with different strength, such a reinforcing bar is a part of a reinforcing bar material whose overall strength is normal, that is, wants to give high strength. Manufactured by heat treating the part. Generally, in order to quench the reinforcing bar material, the reinforcing bar material is inserted into the heating coil.
However, if an attempt is made to increase the strength difference between the normal strength portion and the high strength portion, depending on the conditions of the heat treatment, the influence of the heat treatment on the normal strength portion becomes large, and the difference between the normal strength portion and the high strength portion. There is a problem that the length of the normal strength portion cannot be sufficiently secured, for example, the strength transition portion is formed long.

  The objective of this invention is providing the partial heating apparatus of the reinforcing bar material which can provide a normal intensity | strength part and a high intensity | strength part reliably by shortening the length of an intensity | strength transition part.

The partial heating apparatus for reinforcing bar material of the present invention is characterized by comprising heating means for heating a part of the reinforcing bar material in the longitudinal direction as a heating part.
According to the present invention of this configuration, the heat part is formed as a high-strength part by heat treatment accompanied by heating by the heating means, and most other parts including the adjacent part are formed as normal-strength parts. The heat effect can be made difficult to reach the normal strength portion, and the length of the strength transition portion formed between the high strength portion and the normal strength portion can be shortened to achieve the object. In addition, this makes it possible to clarify the boundary between the high-strength portion and the normal-strength portion, and it is possible to manufacture a rebar that is easy to use.

In this invention, it is preferable to provide the heat conduction control means which controls the heat conduction from the said heating part to the adjacent part which remove | deviated from the said heating part of the said reinforcing bar material.
In the present invention having this configuration, the heat conduction from the heating portion to the adjacent portion is controlled by the heat conduction control means. Therefore, in the reinforcing bar material heated by the heating means, the boundary between the high strength portion and the normal strength portion. Can be further clarified.

In the present invention, the heat conduction control means may be configured to cool the adjacent portion with a cooling medium, or may be configured to heat the adjacent portion to a temperature lower than the heating portion. preferable.
Here, the “temperature lower than the heated portion” specifically refers to a temperature at which quenching is not performed.
In the present invention having this configuration, the adjacent portion is cooled to a low temperature or heated to a temperature lower than that of the heated portion, so that it can be controlled to effectively suppress heat conduction from the heated portion to the adjacent portion.

In this invention, it has a conveyance means which conveys the said some reinforcing steel material so that the said heating means and the said heat conduction control means may be passed, and the conveyance direction by the said conveyance means is a direction orthogonal to the longitudinal direction of the said reinforcement material. Preferably there is.
In the present invention of this configuration, since the plurality of reinforcing bar materials are conveyed to the heating means and the heat conduction control means continuously or intermittently by the conveying means, the high strength portion and the normal strength portion having different strengths in one Can efficiently mass-produce rebars with Furthermore, since the conveying direction and the longitudinal direction of the reinforcing bar material are orthogonal to each other, many reinforcing bars can be manufactured while conveying a short conveying distance, and both downsizing of the apparatus and mass production of reinforcing bars can be realized.

In the present invention, the heating means may be provided corresponding to the center side in the longitudinal direction of the reinforcing bar material, and the conveying means may include holding portions that hold both ends in the longitudinal direction of the reinforcing bar material. Good.
In the present invention of this configuration, a reinforcing bar having a high-strength portion formed on the center side in the longitudinal direction and a normal-strength portion formed on both end sides can be manufactured, and the holding unit is not heated by the heating means, and is transported. Means can be maintained in good condition.

In the present invention, the heating means may be provided corresponding to both ends in the longitudinal direction of the reinforcing bar material, and the conveying means may include a holding portion that holds the central side in the longitudinal direction of the reinforcing bar material. Good.
In the present invention of this configuration, it is possible to manufacture a reinforcing bar in which a normality portion is formed on the center side in the longitudinal direction and a high-strength portion is formed on both end sides, and the holding portion is not heated by the heating means, The conveying means can be maintained in a good state.

In this invention, it is preferable to provide the cooling means which cools the said heating part heated with the said heating means.
In the present invention having this configuration, the heated portion is cooled by the cooling means, whereby the heated portion can be subjected to a heat treatment such as quenching, and a high-strength portion having higher strength can be reliably formed.

  According to the present invention, the normal strength portion and the high strength portion can be reliably provided by shortening the length of the strength transition portion.

The front view which shows the partial heating apparatus which concerns on 1st Embodiment of this invention. The top view which shows the said partial heating apparatus. The whole figure which shows the reinforcing bar manufactured by the heating with the said partial heating apparatus. The top view which shows the partial heating apparatus which concerns on 2nd Embodiment of this invention.

<First Embodiment>
[Overall description of partial heating device]
Hereinafter, the partial heating apparatus 1 which concerns on 1st Embodiment of this invention is demonstrated based on drawing.
In FIG. 1 thru | or FIG. 3, the partial heating apparatus 1 heats a part of the reinforcing bar material 2 which consists of a steel rod of predetermined length dimension, cross-sectional dimension, and intensity | strength. It is an apparatus which manufactures the rebar 3 which it has. Specifically, the reinforcing bar 3 in this embodiment has a high-strength portion 3A on the center side in the longitudinal direction and normal strength portions 3B and 3B on both ends (see FIG. 3).

  As shown in FIG. 1 and FIG. 2, the partial heating device 1 includes a heating means 10 that heats the central side, which is a part of the reinforcing bar material 2 in the longitudinal direction, as a heating part, and an adjacent part that is separated from the heating part of the reinforcing bar material 2 Heat conduction control means 20 for controlling heat conduction from the heating part to the part, cooling means 30 for cooling the heated part heated by the heating means 10, and a plurality of means 10, 20, 30 so as to pass through each part The rebar material 2 is transported continuously or intermittently, and each means 10, 20, 30, 40 is covered with a tunnel-shaped frame 1A.

[Description of heating means]
The heating means 10 is provided so as to correspond to the center side in the longitudinal direction of the reinforcing bar material 2 and is configured to simultaneously heat the heating portions on the center side of the plurality of reinforcing bar materials 2 conveyed by the conveying means 40 for a predetermined time. As such a heating means 10, a pair of heating furnaces 11 such as a resistance heating furnace, an infrared heating furnace, an induction heating furnace, and the like disposed above and below the reinforcing bar material 2 are provided. The upper heating furnace 11 is fixed to the ceiling surface of the frame 1A, and the lower heating furnace 11 is installed on the floor surface.

  The heating temperature of the heated portion by the heating means 10 is about 1000 ° C. as the furnace temperature of the heating furnace 11, and the temperature of the heated portion to be heated is 700 ° C. or higher, desirably about 900 ° C.

  When an induction heating furnace is employed as the heating furnace 11, the conveying direction of the reinforcing bar material 2 (the direction from the left to the right in FIGS. 1 and 2) is orthogonal to the longitudinal direction of the reinforcing bar material 2. Therefore, since it is difficult to pass the rebar material 2 to be conveyed through the heating coil, an induction heating furnace having a structure in which the heating coil and the rebar material 2 are vertically close to each other is used.

[Description of heat conduction control means]
The heat conduction control means 20 is disposed on both sides of the heating means 10 along the longitudinal direction of the reinforcing bar material 2, and the cooling medium is directly applied to the adjacent part adjacent to the heating part of the reinforcing bar material 2 to cool the adjacent part. And it controls so that the heat from the heated heating part may be suppressed from being conducted to both sides of the reinforcing bar material 2 including the adjacent part. As these heat conduction control means 20, it arrange | positions above the reinforcing bar material 2, the cooling medium supply part 21 which supplies a cooling medium to an adjacent part, and is arrange | positioned under the reinforcing bar material 2, and collect | recovers the supplied cooling medium. And the like. The cooling medium supply unit 21 is fixed to the ceiling surface of the frame 1A, and the lower cooling medium receiver 22 is installed on the floor surface.

Examples of the cooling medium include a cooling liquid such as water and oil, and a cooling gas such as air and inert gas. A circulation device (not shown) that circulates the cooling medium while adjusting the temperature is connected to the heat conduction control means 20.

  The cooling temperature of the adjacent portion by the heat conduction control means 20 is a temperature at which the composition of the reinforcing bar material 2 does not change as the temperature of the adjacent portion, that is, a temperature at which quenching is not performed, and is preferably 500 ° C. or less.

[Description of cooling means]
The cooling means 30 is a means for cooling the heated heated portion and performing a heat treatment such as quenching, and is disposed close to the downstream side of the heating means 10 so that the heated portion that has become hot can be cooled. Yes. Like the heat conduction control means 20, such a cooling means 30 is also disposed above the reinforcing bar material 2, disposed below the cooling medium supply unit 31 that directly supplies a cooling medium such as cooling water to the heating portion, And a cooling medium receiver 32 for collecting the cooling medium. Similarly, the cooling medium supply unit 31 is fixed to the ceiling surface of the frame 1A, and the lower cooling medium receiver 32 is installed on the floor surface.

  In the reinforcing bar 3 obtained by cooling the heated portion with the cooling means 30 and heat-treating, as shown in FIG. 3, the heated portion is formed as a high-strength portion 3A and includes other adjacent portions on both sides of the heated portion. Most are formed as a normal strength portion 3B, and a small area between the high strength portion 3A and the normal strength portion 3B is formed as a strength transition portion 3C which is a strong transition portion. That is, the partial heating apparatus 1 of this embodiment functions as a partial heat treatment apparatus by including the heating means 10 and the cooling means 30.

  The strength of the high-strength portion 3A is 685 MPa or more. The strength of the normal strength portion 3B is a predetermined strength that the reinforcing bar material 2 has and is 490 MPa or less. The strength transition portion 3C has a strength gradient that transitions from 490 MPa to 685 MPa, and the length thereof is about the diameter of the reinforcing bar 3. According to the JIS standard, the yield point or 0.2% yield strength of the normal strength portion 3B is as defined in JIS 3112, and the yield point or 0.2% yield strength of the high strength portion 3A is normal strength. It is larger than that of portion 3B.

[Description of conveying means]
The transport means 40 includes two conveyor-type transfer devices 41 and 41 extending along the supply direction of the reinforcing bar material 2. The transfer devices 41 are, for example, drive-side sprockets 42A that are spaced apart from each other at positions corresponding to both sides of the reinforcing bar material 2 and are arranged in parallel with each other and driven in synchronization with each other by a drive source such as an electric motor (not shown). A driven sprocket 42B as an idler, an endless conveyor chain 43 wound around each of the sprockets 42A and 42B, and a plurality of holding portions 44 that are attached to the conveyor chain 43 and hold the ends of the reinforcing bar material 2 Yes.

  Further, in the conveying means 40, two support rails 45, 45 parallel to the transfer device 41 are provided between the pair of transfer devices 41, and the reinforcing material 2 is supported by the support rail 45 from below. The reinforcing bar material 2 is prevented from being bent. The support rail 45 is disposed at a position that does not overlap with the respective means 10, 20, 30 in a plan view.

[Explanation of operation of partial heating device]
Operation | movement of the partial heating apparatus 1 demonstrated above is demonstrated below.
First, on the upstream side of the partial heating device 1 (upstream side in the supply direction of the reinforcing bar material 2), the reinforcing bar material 2 is carried onto the transfer device 41 of the conveying means 40 that is temporarily stopped by a carrying device (not shown). When the carrying-in is completed, the transfer device 41 operates for a predetermined time, and at the same time the carried-in rebar material 2 is carried in the carrying direction, and at the same time, the next reinforcing-bar material 2 can be carried in by the carrying-in device. However, such an operation may be performed continuously instead of intermittently at predetermined time intervals.

  By repeating the above operation, when the plurality of reinforcing bar materials 2 reach the passing positions of the heating means 10 and the heat conduction control means 20, the heating means 10 rebars while the adjacent portions are cooled by the heat conduction control means 20. The heated part of material 2 is heated. When the heated rebar material 2 reaches the cooling means 30, the cooling means 30 rapidly cools the heated portion and completes the heat treatment such as quenching. Thereby, the reinforcing bar 3 having the high strength portion 3A and the normal strength portion 3B is obtained. The obtained reinforcing bar 3 is sent to the most downstream side of the transport means 40 while being sufficiently naturally cooled, and is then transported to a predetermined position by a transport device (not shown).

[Effect of the first embodiment]
According to the above embodiment, the following effects are obtained.
(1) That is, in the partial heating apparatus 1, the heated portion is formed as the high-strength portion 3A by heat treatment accompanied by heating by the heating means 10, and the other most part including the adjacent portion is formed as the normal-strength portion 3B. Therefore, the heat effect during the heat treatment can hardly reach the normal strength portion 3B, and the length of the strength transition portion 3C formed between the high strength portion 3A and the normal strength portion 3B can be shortened. In addition, this makes it possible to clarify the boundary between the high-strength portion 3A and the normal-strength portion 3B, and to manufacture the rebar 3 with good usability.

(2) And, in the reinforcing bar material 2 heated by the heating means 10, the heat conduction from the heating part to the adjacent part is controlled by the heat conduction control means 20, so that the high strength part 3A and the normal strength part 3B The boundaries between each other can be made clearer.
At this time, since the heat conduction control means 20 is configured to cool the adjacent portion with the cooling medium, the adjacent portion can be reliably cooled to a low temperature, and the heat conduction from the heating portion can be effectively suppressed. Can be controlled.

(3) Since the plurality of reinforcing bar materials 2 are conveyed to the respective means 10, 20, and 30 continuously or intermittently by the conveying means 40, the high-strength portion 3A and the normal-strength portion 3B having different strengths in one It is possible to efficiently mass-produce the rebar 3 having the. Furthermore, since the conveyance direction and the longitudinal direction of the reinforcing bar material 2 are orthogonal to each other, many reinforcing bars 3 can be manufactured while conveying a short conveyance distance, and both the downsizing of the apparatus 1 and the mass production of the reinforcing bar 3 are realized. it can.

(4) Since the heating means 10 is provided corresponding to the center side in the longitudinal direction of the reinforcing bar material 2 and the conveying means 40 has the holding portions 44 that hold both ends of the reinforcing bar material 2, the center in the longitudinal direction is provided. The reinforcing bar 3 having the high strength portion 3A formed on the side and the normal strength portions 3B formed on both ends can be manufactured, and the holding portions 44 on both ends are not heated by the heating means 10 on the central side, and are transported. The means 40 can be maintained in a good state, and labor and cost required for maintenance and the like can be reduced.

(5) Since the cooling means 30 for cooling the heated portion heated by the heating means 10 is provided, the heated portion can be cooled by the cooling means 30 so that the heated portion can be subjected to heat treatment such as quenching, A high-strength portion with higher strength can be reliably formed.

Second Embodiment
FIG. 4 shows a plan view of the partial heating apparatus 1 according to the second embodiment of the present invention. In FIG. 4, the same reference numerals are used for the same means and devices as those in the first embodiment described above, and the description of the same means and devices here is omitted or simplified.

  In FIG. 4, in the partial heating apparatus 1 of this embodiment, the heating means 10 and the cooling means 30 are each arrange | positioned corresponding to the both ends of the reinforcing bar material 2, and the heating part of both ends can be heated, cooled, and heat-treated. It is configured as follows. Therefore, in order to control the heat conduction from the heating portions at both ends, the heat conduction control means 20 is placed on the heating means 10 at a position corresponding to the center side of the reinforcing bar material 2 between the pair of heating means 10. Adjacent to each other. On the other hand, the pair of transfer devices 41 are disposed between the pair of heating means 10 and have a holding portion 44 that holds a position corresponding to the center side of the reinforcing bar material 2. Thus, the transfer device 41 is disposed at a position that does not overlap with the heating means 10 on both ends in plan view.

According to the present embodiment, although the configuration is different from that of the first embodiment, the same effects as (1) to (3) and (5) of the first embodiment are obtained, and the effect of (4) is substituted. The following effect (6) is obtained.
(6) That is, since the heating means 10 is provided corresponding to both ends in the longitudinal direction of the reinforcing bar material 2 and the conveying means 40 has the holding portion 44 that holds the central side of the reinforcing bar material 2, the longitudinal direction The reinforcing bars 3 having high strength portions formed on both end sides thereof and normal strength portions formed on the center side can be manufactured, and the holding portions 44 on the center side are not heated by the heating means 10 on both end sides and are transported. The means 40 can be maintained in a good state, and labor and cost required for maintenance and the like can be reduced.

  The present invention is not limited to the above-described embodiments, and modifications, improvements, and the like within the scope that can achieve the object of the present invention are included in the present invention.

  In the above-described embodiment, the heat conduction control means 20 is configured to directly supply the cooling medium to the adjacent portion. However, the present invention is not limited to this. For example, the grip member is made of a material having higher heat conductivity than the reinforcing bar material 2. It is possible to control that the heat from the heating part is released through the gripping member and conducted to other parts including the adjacent part by gripping the adjacent part of the reinforcing bar material 2 with the gripping member.

  According to the heat conduction control means 20 of the embodiment, heat conduction from the heated portion heated by the heating means 10 to the adjacent portion side and heat radiation at the adjacent portion side are not escaped, and the temperature of the heated portion is likely to decrease. However, instead of such a heat conduction control means 20, a heat conduction control means constituted by a heating furnace or the like for heating the adjacent portion to a temperature lower than the heating portion, specifically to a temperature lower than the quenching temperature. May be used. According to such heat conduction control means, the adjacent portion is also heated to a predetermined temperature, so the temperature gradient between the heated portion and the adjacent portion is reduced, and the heat conduction from the heated portion to the adjacent portion side can be controlled, The boundary between the high-strength portion 3A and the normal-strength portion 3B can be clarified, and the temperature of the heating portion is hardly lowered, so that the heating portion can be heated quickly.

  In the said embodiment, although the longitudinal direction of the reinforcing bar material 2 and the conveyance direction were orthogonal, you may mutually be parallel. In such a case, the reinforcing bar material can be conveyed so as to pass through the heating coil, and an induction heating furnace can be suitably used as the heating means. Even in such a case, it is desirable to arrange a plurality of induction heating furnaces in parallel in a direction perpendicular to the conveyance direction so that a plurality of reinforcing bar materials can be conveyed and heated at the same time. It is possible to efficiently mass-produce reinforcing bars having different parts.

  In the said embodiment, although the linear thing was illustrated as the reinforcing bar material 2, the reinforcing bar material previously bent in the position corresponding to the heating part used as a high intensity | strength part may be used. That is, in the case of the first embodiment, a reinforcing bar material bent at the center in the longitudinal direction is used, and in the case of the second embodiment, it is folded into a state having a predetermined length at both ends in the longitudinal direction. Reinforced bar material may be used. At this time, the bending angles are generally 90 °, 135 °, and 180 °, and generally have a bending R that is several times the diameter of the reinforcing bar material.

  In addition, the specific configurations, arrangement positions, and the like of the heating means and the heat conduction control means of the partial heating device are not limited to the above-described embodiments, and may be arbitrarily determined in the implementation.

  INDUSTRIAL APPLICABILITY The present invention can be used for a partial heating apparatus that heats a part of a reinforcing bar material or performs heat treatment by heating or cooling.

  DESCRIPTION OF SYMBOLS 1 ... Partial heating apparatus, 2 ... Reinforcing bar material, 3 ... Reinforcing bar, 3A ... High strength part, 3B ... Normal strength part, 10 ... Heating means, 20 ... Heat conduction control means, 30 ... Cooling means, 40 ... Conveyance means, 44 ... holding part.

Claims (7)

  A partial heating apparatus for reinforcing bar material, comprising heating means for heating a part in the longitudinal direction of the reinforcing bar material as a heating part.   A partial heating apparatus for reinforcing bar material, comprising: heat conduction control means for controlling heat conduction from the heating part to an adjacent part that deviates from the heating part of the reinforcing bar material. In the partial heating apparatus of the reinforcing bar material according to claim 2,
The heat conduction control means is configured to cool the adjacent portion with a cooling medium, or is configured to heat the adjacent portion to a temperature lower than that of the heating portion. Material partial heating device. In the partial heating apparatus of the reinforcing bar material according to any one of claims 1 to 3,
A portion of the reinforcing bar material comprising a conveying unit that conveys the plurality of reinforcing bar materials so as to pass through the heating unit, and a conveying direction by the conveying unit is a direction orthogonal to a longitudinal direction of the reinforcing bar material Heating device. In the partial heating apparatus of the reinforcing bar material according to claim 4,
The heating means is provided corresponding to the center side in the longitudinal direction of the reinforcing bar material, and the conveying means has holding portions that hold both ends in the longitudinal direction of the reinforcing bar material. Partial heating device for rebar materials. In the partial heating apparatus of the reinforcing bar material according to claim 4,
The heating means is provided corresponding to both end sides in the longitudinal direction of the reinforcing bar material, and the conveying means has a holding portion that holds the central side in the longitudinal direction of the reinforcing bar material. Partial heating device for rebar materials. In the partial heating apparatus of the reinforcing bar material according to any one of claims 1 to 6,
A partial heating apparatus for reinforcing bar material, comprising a cooling means for cooling the heated portion heated by the heating means.

Images