JPH09271803A - Method and device for continuous rolling of hot bar steel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To join the hot bar steel in short time while suppressing burr by sliding/fitting the rear end part of preceding hot bar steel the tip part of succeeding hot bar steel and joining/rolling the fitted part with applying shear force. SOLUTION: The rear end part of a preceding hot bar steel 9 is worked to a recessed V shape, the tip part of a succeeding hot bar steel 7 is worked to a projecting I shape. In a joining machine 8, the preceding bar 9 is strongly clamped with a clamp fitting 20, the succeeding bar 7 is strongly clamped with a clamp fitting 19, the preceding bar rear part and succeeding bar tip part are fitted. By respectively pressing a joining upper tool 22, joining lower tool 23 to the fitted part and hitting in by a drive-in-cylinder 18 to make a drive-in tool bite therein, the fitted part is instantly joined. Further, joining is assisted by rolling of a rolling roll 24, stabilized joining can continuously be executed. By this method, generation of oxidized scale is suppressed and the hot bar steel excellent in joining strength is rolled.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rolling technique for hot bar steel, and more particularly to joining hot bar steel and continuous rolling before and after the joining.

The present invention can be applied not only to metallic materials but also to production lines for non-metallic materials.

[0003]

2. Description of the Related Art There is an extremely strong demand for continuous intermediate and finish rolling in a metal hot bar rolling mill to improve productivity, improve yield, reduce misrolls, and automate operations.

The key technology lies in how quickly hot joining can be completed.

If the joining is not completed in a short time, for example, when the joining machine is a traveling type, the traveling distance of the joining machine becomes long and it is difficult to realize.

Further, when the joining machine is a fixed type, since the steel bar material is as thick as about 50 to 70 square, a huge looper for accumulating the steel bar material is required.

Conventionally, as a joining method of bar materials, a flash butt method, an induction heating method, a gas heating method, a fusing method, and a friction method have been proposed.

However, many methods such as the flash butt method, the induction heating method, the gas heating method or the fusing method and the friction method have not been realized yet.

The most difficult one among them is that it takes too much time to join.

Usually, joining of steel bars requires 10 to 20 seconds at the shortest, including preparation before joining, removal of sag due to pressing, removal of burrs, and the like.

Conventional joining devices for rolled hot steel bars are described in, for example, Japanese Patent Laid-Open Nos. 53-5060, 53-14150, and 52-20947.

Further, Japanese Patent Laid-Open No. 5-303 discloses a joining technique by friction between a leading material and a trailing material, and Japanese Laid-Open Patent Publication No. 4-158905 discloses induction welding at a high frequency. A joining technique for joining is described.
Japanese Laid-Open Patent Publication No. 176482 describes a technique in which a preceding material and a following material are overlapped and shear-bonded.

[0013]

[Patent Document 1] Japanese Patent Application Laid-Open No. 5-303
In the technique described in Japanese Patent Publication, since it is friction welding, it takes time to raise the temperature to the melting point, and burrs are generated during upsetting. Therefore, deburring time is required, and a long welding time is required. .

Further, although the high frequency induction heating method disclosed in Japanese Patent Laid-Open No. 4-158905 takes a relatively short time, since it is fusion bonding, burrs are unavoidable during upsetting and deburring work is required.
It takes a lot of deburring time. In this technique, if deburring is omitted, there is a problem that the rolling roll is damaged.

Further, Japanese Laid-Open Patent Publication No. 61-176482 discloses lap shear bonding, but since the active surface immediately after shearing of the shape of the shearing edge is once exposed to the atmosphere, generation of new oxide scale is unavoidable. It is difficult to have sufficient bonding strength to withstand process rolling.

The present invention improves on the above-mentioned conventional drawbacks,
It suppresses the generation of burrs due to joining, joins the hot bar steel in a short time, and also suppresses the generation of oxide scale, enabling the rolling of hot bar steel with excellent bonding strength. It is to provide a compounding device, a continuous rolling method, and a continuous rolling facility.

[0017]

A method for continuously rolling a hot bar steel product according to the present invention is a continuous rolling of a hot bar steel product in which a preceding hot bar steel product and a subsequent hot bar steel product are joined and rolled. In the method, a step of working into a desired shape such that the rear end of the preceding hot bar steel and the leading end of the following hot bar steel fit together, and Between the step of slidingly fitting the end portion and the leading end portion of the trailing hot rod steel material, and the rear end portion of the leading hot rod steel material and the trailing end portion of the trailing hot rod steel material The method includes a step of applying a shearing force to the fitting portion and joining, and a step of continuously rolling the rear end portion of the preceding hot-bar steel material and the leading end portion of the subsequent hot-bar steel material that have been joined. It is characterized by

The hot-bar steel running joining apparatus of the present invention is a hot-bar steel running joining apparatus for joining a preceding hot-bar steel material and a following hot-bar steel material. Preforming means for processing the rear end portion of the hot bar steel material into a desired shape such that the trailing end of the hot bar steel material is fitted with the rear end portion of the preceding hot bar steel material A sliding fitting means for slidingly fitting the trailing end portion of the hot bar steel material, a trailing end portion of the preceding hot bar steel material and a trailing end portion of the trailing hot bar steel material. It is characterized by having a shear joining means for joining by applying a shearing force to the fitting portion.

The hot-rolled steel continuous rolling equipment of the present invention is a hot-rolled steel continuous rolling equipment having a running joining device for joining a preceding hot-rolled steel and a subsequent hot-rolled steel. A rough rolling machine for continuously rough rolling the trailing end of the preceding hot bar steel and the leading end of the following hot bar steel, the trailing end of the preceding hot bar steel and the trailing A preforming machine for processing into a desired shape such that the front end of the hot bar steel material to be fitted is formed, and the rear end part of the preceding hot bar steel material joined and the subsequent hot bar steel material And a finish rolling machine for continuously rolling the tip end portion, wherein the running joint device slides the trailing end portion of the preceding hot bar steel material and the leading end portion of the following hot bar steel material. Shearing force is applied to the fitting portion between the rear end portion of the preceding hot bar steel material and the tip end portion of the following hot bar steel material And having a means.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention was made by paying attention to the fact that, as long as three elements of cleanliness, temperature, and force are adjusted, it is possible to join without melting the base metal. It is also applicable to most steel grades or non-ferrous metals.

The present invention eliminates the adverse effects of the conventional method of joining metals by melting or semi-melting them, and realizes strong joining in a solid state and shortening of time.

Specifically, it is as follows.

1) First, one end and the other end of the billet material to be joined, which is a hot work material, are preformed into a specific shape.

The shape is a fitting type shape suitable for stabilizing the joint.

By adopting the fitting shape, the area of the joint surface can be increased and the initial scale can be reduced during the joint operation.

2) Next, in the joining operation, the primary scale reduction is carried out by utilizing the mutual sliding at the time of fitting the front and rear ends of the two hot work materials.

The sliding speed at this time is preferably 100 mm / s or more.

Next, when the fitting portion is strongly clamped and the driving blade is operated at a high speed, the secondary scale is dropped and the active surface is exposed and pressed at the same time by the superposition shearing action, thereby completing the joining.

That is, it is possible to suppress the generation of oxide scale and perform the bonding for a short time.

At this time, if the shearing stroke is regulated to a specific value and the shearing action is stopped midway, the projection state can be maintained and mechanical coupling can be obtained at the same time.

That is, strong joining can be obtained by a combination of metallurgical joining and mechanical joining.

3) On the other hand, regarding the joining time, the front and rear ends of the billet material, which is a hot work material, are preformed into a specific shape,
By performing the bonding operation separately from the bonding operation in advance, it does not contribute to the bonding time, the upsetting process at the time of bonding and the deburring time caused thereby can be omitted, and the shearing speed can be increased, resulting in 3 Less than a second,
It can be greatly shortened.

As described above, since the present invention is not fusion-bonding, there is no need for an upset process for discharging the scale, and the occurrence of burrs as in the conventional case is eliminated, so that the burr cutting process can be omitted and It is possible to reduce the damage of the rolling rolls in the generation / removal section and further reduce the time significantly.

The hot-rolled material joining method and apparatus of the present invention are based on the following findings. 1) Whether the hot rolled material can be joined depends on the cleanliness C of the joining surface, the material temperature T, and the pressing pressure P.

In this case, it is almost the oxide scale that affects the cleanliness.

If there is no oxide scale, the material can be surely joined by pressure bonding with an appropriate material temperature T and a corresponding pressing pressure P.

Therefore, it is not always necessary to melt the joint surface.

If it is attempted to melt, energy for heating is required, and it takes time to raise the temperature.

Further, it is necessary to increase the amount of upset for discharging the oxides generated during melting, and it is inevitable that the molten metal is squeezed out at the same time as the oxides, so-called burrs are generated, and a cutting process is required. There are disadvantages such as.

2) How to secure the cleanliness C among the three joining elements of the pressing pressure P, the material temperature T, and the cleanliness C of the above 1) is a key to reliable bonding in a short time. Become.

The joint surface can be cleaned by removing and discharging the existing oxide scale.

However, a new oxide scale is generated again, and the newly-generated oxide scale makes it difficult to achieve reliable bonding with sufficient strength.

3) On the other hand, when the material is pulled, the stretched portion can expose the active background without oxide scale, which is convenient for joining. It is well known that once this is exposed to air, a new oxide film is immediately formed, which hinders bonding.

According to the results of experiments conducted by the inventors, when lap shearing is performed, the boundary surface is stretched in the shearing process, and the lapped surface is kept in the state of being shielded from air, so that a new oxide scale is generated. It has been found that the state can be prevented and the pressing force is applied at high temperature, and the three joining elements (cleanliness C, material temperature T, pressing pressure P) are conveniently established and strong joining can be achieved.

4) However, in the lap shear method, the oxide scale formed before that remained at the boundary, and there was a limit to strong bonding.

To improve this, the shear rate is increased and the existing scale is crushed and dispersed to obtain a strong bond.

The shear rate is preferably 100 mm / s or more.

It was also confirmed by experiments that the lap shear method can further increase the bonding strength by removing the oxide scale formed before that just before the bonding.

The present invention skillfully combines the above findings and realizes a strong bonding which has never been achieved.

Next, an embodiment of the joining method of the present invention will be described with reference to FIGS.
This will be described with reference to FIG.

In FIG. 1, 2 is a billet which is a hot work material, and 1 is a billet carrying table which carries a billet 2 which is a hot work material.

Reference numeral 3 denotes a preforming machine for fitting and processing the leading end and the rear end of the billet 2 carried by the billet carrying table 1.

Reference numeral 4 is a heating furnace for preventing the temperature of the billet from being lowered after being processed by the preforming machine 3.
Reference numeral 5 is a transfer table for transferring the billet 2 from the heating furnace 4 to the next step.

6 is a rough mill for rolling the billet 2 to a desired size, 7 is a preceding material which is a preceding billet material, and 9 is a following material which is a following billet material.

Reference numeral 8 is a joining machine for joining the trailing end of the preceding material 7 and the leading end of the following material 9, and an intermediate mill 10 and a finishing mill 11 are arranged on the downstream side thereof.

Instead of the joining machine 8, a joining machine 12 may be arranged between the intermediate mill 10 and the finishing mill 11.

Since the billet 2 is normally conveyed in a high temperature state immediately after continuous casting, the front and rear ends of the billet 2 are preformed by the preforming machine 3 on the inlet side of the heating furnace 4.

The soaking temperature is raised to about 1200 ° C. in the heating furnace 4, and the rough mill 6 rolls from 100 to 130 mm square to 40 to 70 mm square.

After that, they are introduced into the intermediate mill 10 in several rows, and further passed through the finishing mill 11 and rolled to the product size and carried out.

Conventionally, each billet was intermittently rolled, but in the present invention, the joining machine 8 is arranged on the outlet side of the rough mill 6 and on the inlet side of the intermediate mill 10 so that the preceding material 7 and the trailing material 7 are passed. The material 9 was welded during running to enable continuous rolling.

Here, the case of two-row joining and rolling is shown as an example, but since the upstream side is one row, joining work will be performed alternately.

The joining machine is composed of a rough mill 6 and an intermediate mill 10.
It may be placed between the intermediate mill 10 and the finishing mill 11
You may arrange between.

FIG. 2 shows another embodiment of the present invention in which the preforming machine 3'is arranged on the outlet side of the rough mill 6.

When a billet having a normal billet temperature is supplied, it is difficult to carry out the preforming work on the inlet side of the heating furnace 4, and therefore, on the outlet side of the heating furnace 4 as shown in FIG. If the preforming machine 3'is provided and the work is carried out, the same effect as that of FIG. 1 can be obtained.

The joining machine 12 is arranged on the outlet side of the intermediate mill instead of the joining machine 8, and the effect is the same as that in FIG.

Next, the details and sequence of the joining method of the present invention will be described with reference to FIGS.

Preforming is carried out before joining, and is shown in FIG.
As shown in FIG. 5, the rear end portion is press-molded by the rear-end molding metal fitting 13 and the rear-end molding metal fitting 14, and at the same time, the tip end portion is press-molded by the tip molding metal fitting 15.

As another method, the rear end may be formed by the forming roller 16 as shown in FIG. 6 or the tip may be formed by the cutter 17 as shown in FIG.

As for the forming shape, one of the rear end portion of the preceding hot bar steel material and the leading end portion of the following hot bar steel material is processed into a convex I-shape, and the other is formed into the I-shape. It is desirable to process it into a concave V-shape that fits together.

Here, as shown in FIG. 8, the rear end portion of the preceding hot bar steel material is processed into a concave V-shape, and the leading end portion of the subsequent hot bar steel material is convex I-shaped. Is processed into
The rear end portion of the processed hot bar steel material and the leading end portion of the subsequent hot bar steel material are fitted to each other.

The molding direction includes the diamond cross section shown in FIG. 4 and the square cross section shown in FIG. 5, but it may be formed according to the cross sectional shape of the rolling pass gauge, but the diamond cross section shown in FIG. I got good results.

FIG. 8 shows the fitting state of the trailing edge of the preceding material and the leading edge of the following material during joining.

At the time of joining, after strongly clamping each of the trailing material clamp metal fitting 19 and the preceding material clamp metal fitting 20, the upper joining metal fitting 22 and the lower joining metal fitting 23 are pressed against each other, and the driving cylinder 21 drives the driving metal fitting 21. Joining will be completed instantly.

FIG. 10 shows a bonded state.

Since the joining portion 25 has not only the strength of the base material but also the biting into the mating material, there is no separation during conveyance to the rolling roll, and stable joining can be secured.

Further, since the joining is promoted by the reduction by the rolling roll 24 in FIG. 8, stable continuation can be achieved without breaking even in tension rolling.

FIG. 9 shows such a joining order in detail. Material clamp, 2. Sliding fit, 3. Joint press, 4. High speed shear bonding, 5. Open, 6. A rolling process is shown.

1. In the process of (1), the front and rear end preforming is processed in the fitting method at the material stage.

2. In the process of (1), the primary scale is removed by sliding fitting at the time of butting.

3. In the step (1), the lap shearing action is subsequently performed at a high speed to perform metallurgical joining.

4. In the process of (1), the shearing stroke is regulated so that the mechanical joint is held together.

On the other hand, the bonding time is the same as in 2.3.4. However, since the above-mentioned 3.4 is progressing at the same time, it is actually 2.3.
Then, the joining operation is completed, and the time can be shortened at the same time.

Further, there is an advantage that the overlapping portion is flattened by the pressing action of the joining clamp and the driving shearing action can be conveniently formed for joining and rolling.

The joining time is as short as 2.1 seconds in total in the steps 1 to 5.

The above-described fitting direction is the rear end recess,
The tip is convex, but the opposite is also acceptable. Next, the main body of the joining machine will be described with reference to FIGS. 11 to 13.

FIG. 11 shows a transverse cross section of the joining machine, and FIG. 12 shows a longitudinal cross section of the joining machine.
The table roller 26 that conveys the preceding material 7 and the following material 9, the upper clamp head 32 and the lower clamp head 34 that clamps and holds the preceding material 7 and the following material 9, and the upper clamp head 32 and the lower clamp head 34 are respectively supported. Upper press table 31 and lower press table 33, an upper clamp cylinder 30 for vertically moving the upper clamp head 32 up and down via the upper press table 31, a swing cylinder 40 for returning to the origin for synchronization with the material, and a set of joining metal fittings A shift cylinder 41 for moving the material, an oscillating frame 27 that follows the material for synchronization with the material, an oscillating shaft 28 that serves as a fulcrum of the oscillating frame 27 that follows, a butt cylinder 42 that presses the materials together, and a shear to the material. Driving tool 2 that gives force or pressing force
1, a driving cylinder 18 for applying a lap shear force or a pressing force to a driving metal member 21, a lower joining metal member 2 for supporting a material from below when a shearing force or a pressing force is applied to the material from above the material 2
Consists of three.

Subsequent material 9 being conveyed on the table roller 26
The concave portion of the front end portion and the convex portion of the rear end portion of the preceding material 7 are fitted together as shown in FIG.

The leading end of the trailing material 9 is being rolled, but the conveying speed at this location is 0.2 to 10 m / s, the material size is 40 to 70 mm square, and the material temperature is about 900 to 1100 ° C. There are two rows.

Until the trailing material 9 catches up with the trailing end of the preceding material 7 at the standby position of the bonding machine 8, the table roller speed on the upstream side of the bonding machine 8 is the conveying speed of the preceding material 7 (the downstream side of the bonding machine 8). Faster than the table roller speed).

Here, when the fitting portion reaches the joining machine 8, the material is clamped, the material is pressed by the butt cylinder 42 to lower the driving cylinder 18, and the driving metal fitting 21 applies a shearing force to the fitting portion. .

Prior to applying shearing force, the driving cylinder 1
It is also possible to lower 8 and apply a pressing force to the fitting portion from above and below by the fitting 21 to further improve the joint strength.

The method of synchronizing with the material is performed by clamping the material described above. In this case, the swing shaft 28 is used.
The swing frame with the fulcrum as the fulcrum follows.

The origin return can be performed by the swing cylinder 40.

Then, in the next joining operation, since the strands are adjacent to each other, the set of joining fittings is moved by the shift cylinder 41 to join them in the same manner, and continuous rolling is possible.

FIG. 13 shows another embodiment of the push-in cylinder 29 when the rolling mill is placed on the box.
Since it is directed to the corner portion, the frame 45 has a shape convenient for mounting and is built in the swing frame 27 via the cushion 44.

The operation of each part is the same as that of the joining machine 8 shown in FIGS. 11 and 12.

Next, concrete joining operation time and required time will be shown.

Billet size: 120 squares x 4.
A case where the length is 5 m, the weight is 550 kg, the furnace delivery pitch is 42 sec, and the furnace delivery temperature is 1150 ° C. will be described.

Table 1 shows an example of an ordinary billet rolling process.

[0100]

[Table 1]

Table 2 shows the joining operation procedure and required time by the joining machine of the present invention.

[0102]

[Table 2]

The preforming process is carried out on the rough mill entry side, which does not affect the joining time, or on the heating furnace entry side, and the joining is carried out on the intermediate mill entry side in Table 1. The material cross section at the position of the joining machine is 2 mm with a 64 mm diamond
Row rolling. It is necessary for the joining machine to join these materials alternately while running, but the furnace discharge pitch of the materials is 42se as described above.
Since it is around c, it suffices to bond them accordingly. That is, in the synchronous running joining machine, it suffices to return to the original joining start position 42 seconds before the start of the first joining operation and wait for the next joining.

On the other hand, in the joining machine of the present invention, as shown in Table 2,
The possible joining cycle is 2.1 + 2.8 = 4.9 seconds, which is the sum of joining time and running return time, so there is a sufficient margin for 42 seconds. The synchronous travel distance at the time of joining is calculated from the joining time and the speed at the entry side of the intermediate mill, and is 2.1 seconds
Since × 0.2 m / s = 0.42 m, there is no problem in space and it can be easily incorporated into an existing line.

For the primary scale drop, the sliding action at the time of abutment is most effective as described above, but further auxiliary means such as high-pressure water jet, inert gas jet, and scale fly by arc are used together to slide the sliding part. Not only can it be cleaned further, but the range of the scale-removing action is widened even for non-sliding parts,
Reliability can be improved by increasing the bonding area.

As described above, according to this embodiment, the following effects are obtained.

1) Strong bonding is possible in a short time.

2) Since burr is not generated, damage to the rolling roll is reduced.

3) Improvement of product yield, reduction of misroll, and automation of work can be realized.

4) It becomes possible to interrupt the running joining work periodically to abolish the dividing work on the exit side of the finishing mill.

5) The productivity is greatly improved by making the intermediate and finish rolling continuous.

Further, since strong bonding is possible in a short time,
Further, the following effects are obtained.

6) The device can be simplified without the need for a looper.

7) Since the synchronous traveling distance is short, the lifting / lowering operation of the transport table is unnecessary.

8) It can be easily incorporated into an existing line.

[0116]

EFFECTS OF THE INVENTION According to the present invention, it is possible to suppress the occurrence of burrs due to joining, join hot-bar steel materials in a short time, and suppress the generation of oxide scale to roll hot-bar steel materials having excellent bonding strength. It is possible to provide an enabling hot-bar steel running joining device, a continuous rolling method, and a continuous rolling facility.

[Brief description of drawings]

FIG. 1 is a continuous rolling facility according to an embodiment of the present invention.

FIG. 2 is a continuous rolling facility according to an embodiment of the present invention.

FIG. 3 shows an example of a preforming machine of the present invention.

FIG. 4 is a front view of a preforming process which is an embodiment of the present invention.

FIG. 5 is a front view of a preforming process which is an embodiment of the present invention.

FIG. 6 shows a preforming process which is an embodiment of the present invention.

FIG. 7 shows a preforming process which is an embodiment of the present invention.

FIG. 8 is a bonding / rolling state diagram showing an embodiment of the present invention.

FIG. 9 is an explanatory view of a joining procedure which is an embodiment of the present invention.

FIG. 10 is a detailed explanatory view of a joint portion which is an embodiment of the present invention.

FIG. 11 is a side view of the joining machine according to the embodiment of the present invention.

FIG. 12 is a front view of a joining machine that is an embodiment of the present invention.

FIG. 13 is a front view of a joining machine that is an embodiment of the present invention.

[Explanation of symbols]

1 ... Billet transport table, 2 ... Billet, 3 ... Preforming machine, 3 '... Preforming machine, 4 ... Heating furnace, 5 ... Transport table, 6 ... Rough mill, 7 ... Preceding material, 8, 12 ... Joining Machine,
9 ... Subsequent material, 10 ... Intermediate mill, 11 ... Finishing mill, 13,
14 ... rear end metal fitting, 15 ... front end metal fitting, 16 ... forming roller, 17 ... cutter, 18 ... driving cylinder,
19 ... Trailing material clamp fittings, 20 ... Leading material clamp fittings, 21 ... Driving fittings, 22 ... Joining upper fittings, 23 ... Joining lower fittings, 24 ... Rolls, 25 ... Joining parts, 26 ... Table rollers, 27 ... Shaking Moving frame, 28 ... Swing shaft, 30
... upper clamp cylinder, 31 ... upper press table, 32 ... upper clamp head, 33 ... lower press table, 34 ... lower clamp head, 35 ... joining lower frame, 36, 39 ... metal fitting lifting cylinder, 40 ... swing cylinder, 41 ... Shift cylinder, 42 ... Butt cylinder, 43 ... Foundation, 4
4 ... Cushion, 45 ... Frame.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Toshiyuki Kajiwara 4-6 Kanda Surugadai, Chiyoda-ku, Tokyo Hitachi Ltd. Inside the Hitachi Research Laboratory, Hitachi Ltd. (72) Gen Nagakubo, 7-1, 1-1 Omikacho, Hitachi City, Ibaraki Prefecture Inside Hitachi Research Laboratory, Hitachi Ltd.

Claims (20)

[Claims] Claim: What is claimed is: 1. A continuous rolling method for hot-rolled steel products, comprising joining and rolling a preceding hot-rolled steel product and a subsequent hot-rolled steel product. The step of working into a desired shape such that the leading end portion of the hot working steel bar to be fitted is fitted, and the rear end portion of the preceding hot working steel bar and the leading end of the following hot working steel bar are slid. A step of moving and fitting, and a step of applying a shearing force to the fitting portion between the rear end portion of the preceding hot bar steel material and the leading end portion of the subsequent hot bar steel material to join them,
And a step of continuously rolling a rear end portion of the preceding hot-rolled steel material and a leading end portion of the following hot-rolled steel material that have been joined. 2. A method for continuously rolling a hot-rolled steel product, comprising joining a preceding hot-rolled steel product and a subsequent hot-rolled steel product, and rolling the same. Process into a desired shape that fits the tip of the hot steel bar to be run,
The trailing end of the processed hot bar steel and the trailing end of the following hot bar steel are continuously rolled, and the trailing end of the preceding hot bar and the trailing heat The front end of the hot bar steel is slidably fitted to each other, and a shearing force is applied to the fitting part between the rear end of the preceding hot bar steel and the front end of the subsequent hot bar steel to join them. Then, the continuous rolling method of the hot bar steel product, characterized in that the joined rear end part of the hot bar steel product and the leading end part of the subsequent hot bar steel product are continuously rolled. 3. A method for continuously rolling a hot bar steel product, which comprises joining and rolling a preceding hot bar steel product and a subsequent hot bar steel product in a continuous rolling method. After continuously rolling the leading end of the hot working bar steel, the rear end of the preceding hot working bar and the leading end of the following hot working bar are fitted into a desired shape. After processing, the rear end of the preceding hot bar steel and the leading end of the following hot bar steel are slidably fitted to each other, and the rear end of the preceding hot bar steel and the following Applying a shearing force to the fitting portion with the tip of the hot bar steel material to join, and joining the rear end part of the preceding hot bar steel material and the leading end part of the following hot bar steel material that are joined Method for continuously rolling hot bar steel, characterized in that the rolling is carried out mechanically. 4. A method for continuously rolling a hot bar steel product, comprising joining a preceding hot bar steel product and a subsequent hot bar steel product together and rolling them, wherein a trailing end portion of the preceding hot bar steel product and the subsequent A step of continuously rough rolling the leading end portion of the hot bar steel material to be carried out, and a desired hot-bar steel material fitting the rear end part of the preceding hot bar steel material and the leading end part of the following hot bar steel material to each other. A step of forming into a shape, a step of continuously intermediate rolling the trailing end of the preceding hot bar steel and the leading end of the following hot bar steel, and the trailing end of the preceding hot bar Part and the trailing end of the hot bar steel product are slidably fitted together, and fitting of the trailing end part of the preceding hot bar steel product and the leading end part of the following hot bar steel product A step of applying a shearing force to the joining portion and continuously rolling the joined rear end portion of the preceding hot bar steel material and the trailing end portion of the following hot bar steel material Continuous rolling method of hot steel bar material and having a degree. 5. The continuous rolling method for hot-rolled steel according to claim 4, wherein the rough rolling is performed in one row, the intermediate rolling is performed in double row, and the hot rolling is performed in double row before the intermediate rolling. A continuous rolling method for hot steel bars, which comprises alternately joining steel bars. 6. The hot rolling method according to claim 4, wherein the joining work before the intermediate rolling is periodically interrupted and the dividing work after the intermediate rolling is abolished. Continuous rolling method for steel bars. 7. The continuous rolling method for hot-rolled steel according to any one of claims 1 to 6, wherein the sliding speed in the fitting step is 100 mm / s or more and the joining step is performed. A continuous rolling method for a hot bar steel material, characterized in that the shear rate is 100 mm / s or more. 8. The continuous rolling method for hot-rolled steel according to claim 1, wherein the fitting portion is pressed in the vertical direction before applying the shearing force in the joining step. A method for continuously rolling a hot bar steel material, which is characterized in that: 9. The continuous rolling method for hot-rolled steel according to any one of claims 1 to 8, wherein the shearing force in the joining step is set so that burrs do not occur in the hot-rolled steel. A continuous rolling method for hot-rolled steel, characterized by adjusting the shear stroke to be applied. 10. A continuous rolling method for hot-rolled steel according to any one of claims 1 to 9, wherein in the step of working into the desired shape, the trailing end portion of the preceding hot-rolled steel and the trailing end thereof are formed. Hot bar, wherein either one of the tips of the steel bar is processed into a convex I-shape, and the other is processed into a concave V-shape that fits with the I-shape. Continuous rolling method for steel. 11. A hot-bar steel running joining apparatus for joining a preceding hot-bar steel material and a following hot-bar steel material, wherein the trailing end portion of the preceding hot-bar steel material is followed by the trailing end portion of the preceding hot-bar steel material. A preforming means for processing into a desired shape such that the tip portion of the hot rod steel material is fitted, a rear end portion of the preceding hot rod steel material and a tip portion of the trailing hot rod steel material. Sliding fitting means for sliding and fitting, and shearing for joining by applying a shearing force to the fitting portion between the rear end of the preceding hot bar steel and the leading end of the following hot bar steel A hot welding apparatus for hot bar steel, comprising: a joining means. 12. The hot welding apparatus for hot bar steel according to claim 11, wherein the sliding fitting means adjusts the sliding speed to 100 mm / s or more and the shear joining means. A hot-running steel bar joining apparatus comprising means for adjusting the shear rate to 100 mm / s or more. 13. A hot-bar steel running joining device according to claim 11 or 12, wherein the desired shape in said preforming means is such that the preceding hot-bar steel material has a rear end portion and Either one of the leading ends of the subsequent hot bar steel material has a convex shape I
A hot-bar steel running joining device, characterized in that it has a mold shape, and the other has a concave V-shape that fits with the I-shape. 14. A hot-bar steel running joining apparatus according to any one of claims 11 to 13, wherein the trailing end portion of the preceding hot-bar steel material and the trailing hot-bar steel material are A hot-running steel bar joining apparatus comprising a pressing means for pressing a fitting portion with a tip portion in a vertical direction. 15. A hot-bar steel running joining apparatus according to any one of claims 11 to 14, wherein the shear joining means has a shear stroke adjusting means for adjusting a stroke of shearing. A hot welding device for hot bar steel. 16. The hot welding apparatus for hot bar steel according to any one of claims 11 to 15, wherein the running speed of the hot steel bar running and the hot running welding apparatus running. A material clamp synchronizing means for performing synchronization, a driving means for returning the origin of the speed synchronization, a swinging means for swinging the running joint device, and a swing shaft serving as a fulcrum of swinging of the running joint device. A hot-bar steel running joining device, characterized by having: 17. The hot-bar steel running joining apparatus according to claim 11, wherein a plurality of the sliding fitting means are arranged in parallel along the traveling direction of the hot steel bar. Each of the plurality of the sliding fitting means is provided with a moving means for moving the shear joining means so as to arrange the shear joining means at each fitting portion. Inter-bonding device. 18. A continuous rolling facility for hot-rolled steel products, comprising a hot-rolling joining device for joining a preceding hot-rolled steel product and a subsequent hot-rolled steel product, wherein a trailing end portion of the preceding hot-rolled steel product is provided. And a rough rolling machine that continuously rough-rolls the leading end of the trailing hot rod steel, and fits the trailing end of the preceding hot rod steel and the leading end of the trailing hot rod steel. A preforming machine for processing into a desired shape that fits, and a finish rolling machine for continuously rolling the rear end portion of the preceding hot-bar steel material joined and the leading end portion of the subsequent hot-bar steel material. And the running joint device,
Means for slidingly fitting the trailing end of the preceding hot bar steel and the leading end of the following hot bar steel, and the trailing end of the preceding hot bar steel A continuous rolling facility for hot bar steel, comprising means for applying a shearing force to the fitting portion of the hot bar steel with the tip end of the hot bar. 19. A continuous rolling facility for hot-rolled steel products, comprising a hot-rolling device for joining a preceding hot-rolled steel product and a subsequent hot-rolled steel product, wherein a trailing end portion of the preceding hot-rolled steel product is provided. And a rough rolling machine that continuously rough-rolls the leading end portion of the following hot-rolled steel material, and fits the trailing end portion of the preceding hot-rolled steel material and the leading end portion of the following hot-rolled steel material. A preforming machine that processes into a desired shape that fits, an intermediate rolling machine that continuously intermediate-rolls the trailing end portion of the preceding hot bar steel material and the leading end portion of the following hot bar steel material, The trailing end portion of the preceding hot bar steel and the finishing rolling machine for continuously rolling the leading end of the following hot bar steel are sequentially arranged, and the running joining device is configured to provide the preceding hot bar. Means for slidingly fitting the rear end of the steel bar and the leading end of the following hot steel bar, the rear end of the preceding hot steel bar and the trailing end And a means for joining by applying a shearing force to the fitting portion with the tip portion of the hot bar steel, and the running joining device is provided between the rough rolling mill and the intermediate rolling mill or the intermediate rolling mill. A continuous rolling facility for hot bar steel, which is arranged between a rolling mill and the finish rolling mill. 20. A continuous rolling facility for hot-rolled steel products, comprising a hot-rolling device for joining a preceding hot-rolled steel product and a subsequent hot-rolled steel product, wherein a trailing end portion of the preceding hot-rolled steel product is provided. And a trailing end of the hot bar steel material to be fitted into a desired shape, a preforming machine, a trailing end portion of the preceding hot bar steel material and the trailing hot bar steel material A rough rolling machine that continuously rough-rolls the tip end of the, and an intermediate rolling mill that continuously intermediate-rolls the leading end of the preceding hot bar steel and the leading end of the following hot bar steel, The trailing end portion of the preceding hot bar steel material and a finishing rolling machine for continuously rolling the leading end portion of the following hot bar steel material are sequentially arranged, and the running joining device is configured to perform the preceding hot work. Means for slidingly fitting the rear end of the steel bar and the leading end of the following hot steel bar, the rear end of the preceding hot steel bar and the trailing end And a means for joining by applying a shearing force to the fitting portion with the tip portion of the hot bar steel material, and the running joining device is between the preforming machine and the intermediate rolling mill or the intermediate A continuous rolling facility for hot bar steel, which is arranged between a rolling mill and the finish rolling mill.