JP2002224856A - Friction welding method and device for bar stock - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and a device for bar stock by friction welding of which equipment is compact, in which the consumption of energy is small and continuous rolling or the like of the bar stock is advantageously realized by joining bar stocks in succession. SOLUTION: In the method and the suitable device for performing the method, a first bar stock B1 and a second bar stock B2 which are arranged in series are moved in the longitudinal direction of the bar stock, an insert stock I1 (or I2) is inserted between the bar stocks, (1) the insert stock I1 is rotationally brought into contact with the first and second bar stocks and the insert stock is joined to the first and second bar stocks by frictional heat while moving it in the same direction as that of the first and second bar stocks or (2) the insert stock I2 is rotationally brought into contact with the first and second bar stocks, the insert stock is extracted from the position after frictional heat is imparted to the contact part and the first bar stock is joined to the second bar stock.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for friction welding a bar, which is particularly advantageous when the bars are joined and continuously rolled.

[0002]

2. Description of the Related Art When a bar material (bar-shaped steel material), for example, a billet is fed into a rolling mill at an ironworks, if the billets are joined one after another and continuously fed, the yield, productivity, quality and machine life are extended. There are many advantages, and the need for such continuous rolling is great. As a joining technique for making this continuous rolling possible, not only a bar but also an entire steel material including a hot-rolled steel sheet and the like, an induction heating pressure welding method as shown in FIG. -76006, JP-A-7-004), flash butt welding as shown in (b) (for example, JP-A-8-267107), and (c).
(Japanese Patent Application Laid-Open No. Hei 5-237767).

In the induction heating pressure welding method, materials to be welded M, M are respectively held by clamps 10, 10 so that the end faces to be welded are separated from each other. Then, a thrust F in the mutually approaching direction is applied to the materials to be joined M, M to press-join the induction heating section. Note that one of the materials to be joined may be stationary and thrust may be applied to the other.

[0004] The flash butt welding method uses a material to be joined M,
M is gripped by the electrodes 12 and 12, respectively, so that the end faces to be joined are brought into contact and opposed to each other, and a large current is applied between the joined materials M and M for a short time to melt the joined ends and approach the joined materials M and M mutually. A thrust F in the direction is applied to press-bond the melted portion. Note that one of the materials to be joined may be stationary and thrust may be applied to the other.

In the friction welding method, the workpieces M, M are gripped by clamps 10, 10A, respectively, so that the end faces to be welded are separated from each other, and while one of them is rotated, a thrust F is applied thereto to make contact with the other. As a result, frictional heat is generated at the end face to be joined, and when the contact portion reaches a joinable temperature, the rotation is stopped, the thrust is increased, and the contact portion is brought into pressure contact. The thrust may be applied to the non-rotating side instead of the rotating side.

In the friction welding method, the number of revolutions, pressure (thrust per unit sectional area) of a material to be welded, and a relative pushing distance between the materials to be welded (this distance is referred to as a "crossover") determine the quality of welding. It is an important factor that influences. The qualitative relationship of these factors is shown in FIG. In this figure, the pressure P
"Friction closer to" the process of from the rising start until the fall start of the rotational speed N of, refers to the required time τ _F of this process as "friction time", "friction value X _F of the approach margin X at the time of friction closer to the end X _F / τ _F is called “friction approach speed”. Moreover, the process from the fall start of the rotational speed N to the falling end of the pressure P "upset", "upset time" required time tau _A of the process, the highest reached value and friction closer margin X _F of the approach margin X Is referred to as the “upset amount”. Also, friction closer, set pressure P _F of at upset, respectively P _A "frictional pressure", as "upset pressure".

[0007] Although not shown, in addition to the above, other than the above, a sliding pressure bonding method in which the opposed end faces of the materials to be joined are slid in a linear direction (a thickness direction or a width direction) and joined (for example, JP-A-7-4740)
No. 8 and the aforementioned JP-A-5-237671).

[0008]

Among the various joining techniques, any joining method other than the friction welding method requires additional heating means (such as an induction coil and an energizing device), and the apparatus becomes too complicated, resulting in energy costs. Is too expensive. Therefore, it is considered that the friction welding method, which does not require a separate heating means and can make the apparatus configuration more compact than other methods, is most advantageous for joining the rods.

In the conventional method of the friction welding method, in the case of a rod, as shown in FIG. 7, first and second rods B arranged in series as shown in FIG.
1, the rotation of one of B2 (for example, B1) is restricted, and the other (for example, B2) is rotated to apply a thrust to one of the rods B1 and B2 to perform frictional approach or further upset. Things. In the friction welding method as shown in FIG. 7, in order to obtain a sound joining, the number of impurities (scale, etc.) existing at the end of the bar is increased by increasing the rotational speed near the friction.
Centrifugation necessary to remove the semi-molten portion (the portion that has become semi-molten due to frictional heat) containing the outside of the joint (the one that is fixed to the outer periphery of the bar is called "burr") It is necessary to apply force and stop the rotation suddenly before the oxide film is formed on the active surface exposed by removing the semi-molten portion to perform upsetting. However, in order to reliably perform stable high-speed rotation and abrupt stop for a long and heavy bar, it is necessary to increase the size of the rotating means and the gantry, which causes a problem of high equipment cost.

In order to prevent oxidation of the surfaces to be joined, Japanese Patent Application Laid-Open No. Hei 5-237671 proposes that a reducing agent be interposed between the surfaces to be joined. However, this requires a complicated apparatus. There is a possibility that the reducing agent itself becomes an intervening substance and remains in the joining portion, resulting in poor joining. In addition, the above-mentioned JP-A-7-
No. 1004 proposes to spray a reducing flame to the part to be joined, but this goes against energy saving,
The equipment is also complicated, which may increase costs.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems, to reduce the size of the equipment and to reduce the energy consumption, and to realize the friction of a bar which can be successively joined by successively rolling the bars. It is an object of the present invention to provide a pressure welding method and apparatus.

[0012]

The gist of the present invention to solve the above-mentioned problems lies in a method and an apparatus for friction-welding a bar described below. (1) The first and second bars arranged in series are moved in the longitudinal direction of the bars, an insert is inserted between the bars, and moved in the same direction as the first and second bars. A friction welding method for rods, wherein the insert is rotated by contacting the insert with the first and second rods while the insert is being joined to the first and second rods by frictional heat.

(2) The first and second rods arranged in series are moved in the longitudinal direction of the rods, and an insert is inserted between the rods to be the same as the first and second rods. After moving the insert material in contact with the first and second bars while rotating in the direction to apply frictional heat to the contact portion, the insert material is extracted from the position, and the first and second bars are removed. A friction welding method for rods, characterized by joining.

(3) First and second clamps for respectively restraining the first and second rods arranged in series, a rotary chuck for gripping and rotating the insert material, and the first and second clamps. A reciprocating drive means for moving a clamp and the rotary chuck in the longitudinal direction of the bar;
Moving means for moving in the direction between the second bars, and wherein the moving means is capable of inserting an insert material gripped by the rotary chuck between the first and second bars. A friction welding apparatus for a rod material.

(4) First and second clamps for respectively restraining the first and second bars arranged in series, a rotary chuck for supporting and rotating the insert, and the first and second clamps. A reciprocating drive means for moving a clamp and the rotary chuck in the longitudinal direction of the bar;
Moving means for moving in the direction between the second bars, the moving means having a function of inserting the insert material between the first and second bars and further having a function of extracting. Material friction welding equipment.

Here, "arranged in series" means that a plurality of objects are arranged in a line in a direction of each major axis (an axis orthogonal to a cross section perpendicular to the longitudinal direction and passing through the center of the cross section). means.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First, the method (1) will be described. The method according to the first aspect of the present invention, as shown in FIG.
While inserting the insert material I1 between the first and second bar materials B1 and B2 and moving the insert material I1 in the same direction as the first and second bar materials B1 and B2, the insert material I1 is first and second bars. Material B1,
B1 is contacted and rotated to obtain frictional heat, and a thrust is applied to the insert material I1 with respect to the first bar material B1, so that the insert material I
By giving a thrust to the second bar B2 with respect to 1,
First bar material B1, insert material I1, insert material I1
And the second bar B2 are joined almost simultaneously.

The insert I1 is composed of the first and second rods B
1 and B2, the diameter of which is substantially the same as that of the rods B1 and B2 and which is shorter and lighter than that of the rods B1 and B2. Energy consumption to obtain is small. During the period from the start of the frictional approach to the end of the upset, the insert material I1 and the first and second bars B1 and B2 remain in contact with each other without interruption, so that the outside air ( Oxygen) does not enter, and the problem of poor bonding due to oxidation of the active surface does not occur.

For example, in the bar rolling equipment, when the first bar B1 is made to correspond to the preceding bar, in order to prevent the process of the preceding bar from being hindered, contact rotation (deviation) and pressing (upset) are performed. ) Thrust at the time of the insert material I1 and the second
To the bar material B2. Since the insert material I1 is joined to the first and second bar materials B1 and B2 and processed together therewith, in order to perform this process stably,
Further, in order to adopt the product after the treatment, it is preferable that the material and the cross-sectional dimension are the same as those of the first and second bars B1 and B2. Of course, the insert material I1 is first for weight reduction,
It is shorter than the second bars B1 and B2.

In this case, the first and second bars B1 and B2 preferably have a circular cross section. This is because, in a cross-sectional shape other than a circular shape, in order to smoothly perform processing after joining, the first and second rods B1, B2, which are non-rotating sides when the rotation of the insert material I1, which is the rotating side, are stopped. Circumferential alignment (for example, in the case of a square bar, rotation must be stopped at a position where the corners meet) is required. To ensure this alignment, the rotation of the insert I1 is more strictly controlled. This is necessary, and the device becomes complicated.

Next, the method (2) will be described. The method according to the present invention according to claim 2 comprises the following steps:
While inserting the insert I2 between the second bars B1 and B2 and moving the insert I2 in the same direction as the first and second bars, the insert I2 is inserted into the first and second bars B1 and B2. Contact heat is applied to obtain frictional heat, insert material I2 is extracted from between first and second bars B1, B2, and thrust is applied to second bar B2 with respect to first bar B1. , First, second
Are joined together.

The insert material I2 is composed of the first and second bar materials B.
Since it is only necessary to be lighter than 1, B2, the device for rotating the device can be made more compact, and the energy consumption for obtaining the centrifugal force required to eliminate the semi-molten portion can be reduced. For example, in the bar rolling equipment, when the first bar B1 is made to correspond to the preceding bar,
In order not to hinder the processing of the preceding material, the thrust at the time of contact rotation (closer to friction) is applied to the insert material I2 and the second bar material B2.
The thrust at the time of pressing (upset) is applied to the second bar B2.

The insert I2 is composed of the first and second rods B
1 and B2 are used only to generate frictional heat, and are not joined to the first and second bars B1 and B2. Therefore, the cross-sectional shape of the insert material I2 can be arbitrarily selected. From the viewpoint of increasing the frictional heat generation efficiency, the insert material I2 is constituted by a disk (rotary disk) having a disk surface larger than the cross section of the first and second rods B1, B2, and a portion of the disk surface separated from the center of rotation. To the first and second bars B1, B2
It is good to make contact. In this case, a higher peripheral speed can be obtained even at the same rotational speed, and the frictional heat generation efficiency can be increased. Of course, the board surface shape may be a circular shape, a polygonal shape, or any other shape, and one or two or more holes are appropriately formed in portions of the board surface that do not come into contact with the first and second bars B1 and B2. It may be provided.

The insert I2 is made of a material having excellent strength, rigidity and abrasion resistance, for example, JIS G45.
S25C and S45C specified in 01 are preferable. Further, since the first and second non-rotating rods B1 and B2 are directly joined to each other, there is no need to perform circumferential alignment between the rotating side and the non-rotating side at the time of joining. Bar material B1, B
The cross-sectional shape of 2 is not limited to a circular shape, but may be a polygonal shape, a hollow cylindrical (pipe) cross-sectional shape, or any other shape.

In the method (2), the insert material I2
Insertion ⇒ frictional approach ⇒ insert material I2 extraction ⇒ upset is performed in order, so a gap is generated between the joined ends, although momentarily, and there is no risk of oxidation of the active surface due to intrusion of oxygen. Absent. Therefore, before the upset, it is preferable that the area to be joined is kept in a non-oxidizing atmosphere.

Next, the device (3) and the device (4) will be described. The device of the present invention according to claim 3 is a device suitable for carrying out the method (1). As shown in FIG. 3 or FIG. 9, the first and second rods B1, B2 arranged in series are arranged. The first and second clamps 1a and 1b to be respectively restrained, the rotary chuck 2A for gripping and rotating the rod-shaped insert material I1, and the insert material I1 are inserted between the first and second bar materials B1 and B2. The moving means 5 of the rotating chuck 2A, the gantry 6 supporting the rotating chuck 2A and the moving means 5, the gantry 4 supporting the second clamp 1b, and the first
And a cradle 3 for supporting the clamps 1a.
It is provided with.

The gantry 3 is designed to be able to run at the same speed v when the first bar B1 moves at a predetermined speed v. Further, the gantry 4 and 6 may be placed on the gantry 3. The moving means 5 of the rotary chuck 2A need not be placed on the gantry 6. The rotational force for joining can be given by the rotary chuck 2A, and the thrust can be given by the frames 4 and 6 provided with advance / retreat driving means (not shown). Each advance / retreat driving means can be constituted by a hydraulic cylinder, for example.

As the rotary chuck 2A, for example, a gear in which a part of the outer periphery is cut out and a claw for gripping a bar are disposed therein, and the notch is a member which is opened only when the bar passes therethrough. Make up so that there is no missing part of the outer gear. As the power for rotation, for example, a rotational motion from an electric motor is transmitted to a rotary chuck by meshing gears.

The method (1) can be performed by operating the apparatus (3) according to the following procedure. (3-1) Run (or stop) at the same speed as the speed v of the first bar B1 (including when v = 0 (stationary)) on the gantry 3
While rotating, the first clamp 1a grips the first bar B1 to restrict its rotation, and the second clamp 1b
Is grasped and restrained.

(3-2) The insert material I1 is gripped by the rotary chuck 2A, and the first and second bar materials B are moved by the moving means 5.
1. Insert between B2. (3-3) The rotating chuck 2A is rotated to rotate the insert material I1 at a predetermined number of rotations. (3-4) The rotary chuck 2A and the second clamp 1b are advanced by the forward / backward drive means of the gantry 6 and the forward / backward drive means of the gantry 4, and the insert material I1 is inserted into the first bar material B1 and the second bar material. B
2 is brought into contact with the insert material I1, and further advanced by a distance corresponding to a predetermined frictional allowance. By this advance, a thrust is applied to the insert material I1 and the second bar material B2.

(3-5) Stop the rotation of the rotary chuck 2A,
The rotary chuck 2 is moved by the reciprocating drive means of the mount 6 and the mount 4.
A and the second clamp 1b are further advanced by a distance corresponding to a predetermined upset amount. When this advance is completed, the joining of the materials (the first bar B1, the insert I1, and the second bar B2) is completed. (3-6) Release the joined materials, and mount 4 and 6
The second clamp 1b and the rotary chuck 2A are moved back to the original position on the gantry 3 by the advance / retreat driving means, and the gantry 3 is also moved to return to the original position (in the case of being stationary).

According to a fourth aspect of the present invention, there is provided a method (2).
As shown in FIG. 4, in the apparatus (3), the moving means 5 includes first and second rods B1, B2 while the insert member I2 is supported by the rotary chuck 2B.
It has the function of being inserted between and further extracting. Equipment (4)
The operation procedure of (4-1) to (4-4) conforms to (3-1) to (3-4) of the operation procedure of the device (3).

(4-5) Stop the rotation of the rotary chuck 2B,
Alternatively, without stopping, the insert material I2
Is extracted from the space between the first and second bar materials B1 and B2, and the second clamp 1b is further advanced by a distance corresponding to a predetermined upset amount by the advance / retreat driving means of the gantry 4. When this advance is completed, the material (first bar B1, second bar B)
The joining of 2) is completed.

(4-6) The joined material is released and the gantry 4
The second clamp 1b and the rotary chuck 2B are moved back to the original position on the gantry 3 by the reciprocating drive means of the gantry 6, and the gantry 3 is moved back to the original position. As it is). It is preferable that the apparatus (4) is provided with an atmosphere adjusting means in order to make the atmosphere around the joined portion a non-oxidizing atmosphere before the upset. This atmosphere adjusting means can be constituted by, for example, a nozzle device capable of appropriately blowing a non-oxidizing gas such as a nitrogen gas or an argon gas to a portion to be joined.

[0035]

[Embodiment 1] Using the apparatus shown in FIG.
170mmφ × 12 with steel composition equivalent to SG4501 S45C
First and second round billets of m length (bar-shaped steel material with circular cross section)
And the same length and length as the first and second bars
Using a 300 mm rod-shaped material as an insert material, a friction welding test was performed at room temperature by the method (1) of the present invention, and a sound bond having a tensile rupture strength equal to or higher than that of the base material was obtained under the following conditions. The first bar was stationary (v = 0).

Rotation speed 400 rpm Friction pressure 58.8 MPa (6 kgf / mm ² ) Upset pressure 117.6 MPa (12 kgf / mm ² ) Friction approach speed 0.2 mm / s Friction allowance 3 mm Upset amount 5 mm Cost by this method Was calculated and compared with the conventional method shown in FIG.
5. Energy cost was 90.

[Embodiment 2] Using the apparatus shown in FIG.
130mm □ × 1 with steel composition equivalent to IS G4501 S45C
First, 2m square billet (bar-shaped steel material with square cross section)
The second bar is made of JIS G4501 S45C and 20mm thick.
Using a disk-shaped material of 1000 mmφ as an insert material, a friction welding test was conducted at room temperature by the method (2) of the present invention, and a sound bond having a tensile rupture strength equal to or higher than that of the base material was obtained under the following conditions. The first bar was stationary (v = 0). Also,
In this example, no joining failure occurred even if the surroundings of the joining portion were not set to the non-oxidizing atmosphere.

Rotation speed 400 rpm Friction pressure 58.8 MPa (6 kgf / mm ² ) Upset pressure 117.6 MPa (12 kgf / mm ² ) Friction approach speed 0.2 mm / s Friction allowance 3 mm Upset amount 5 mm Cost by this method Was calculated and compared with the conventional method shown in FIG.
0 and 88 in energy costs.

In the embodiment, the case where the cold rod is joined is shown. However, it is needless to say that the present invention can be applied to the joining of the hot rod. In this case, a sound bond can be obtained with a smaller energy cost than in the case of (1).

[0040]

As described above, according to the present invention, when friction is approached,
Or, by inserting an insert material between the two bars at the time of friction shift and upset, it becomes possible to perform bar material friction welding for joining each billet one after another with low equipment cost and energy cost, By interposing the insert between the two bars only when the friction is approaching, an excellent effect is achieved in that the bars having a non-circular cross section can be joined without difficulty.

[Brief description of the drawings]

FIG. 1 is a schematic three-dimensional view showing an outline of a method (1).

FIG. 2 is a schematic three-dimensional view showing an outline of a method (2).

FIG. 3 is a schematic plan view showing an outline of an example of a device (3).

FIG. 4 is a schematic plan view showing an outline of a device (4).

FIG. 5 is a schematic side view showing various joining methods.

FIG. 6 is a transition diagram showing a qualitative relationship among a rotational speed, a pressure, and a margin in friction welding.

FIG. 7 is a schematic three-dimensional view showing an outline of a conventional friction welding method.

FIG. 8 is a schematic plan view showing an outline of an apparatus suitable for carrying out a conventional friction welding method.

FIG. 9 is a schematic plan view showing the outline of another example of the device (3).

[Explanation of symbols]

 B1 First bar B2 Second bar I Insert material I1 Insert material (rod shape) I2 Insert material (disk shape) M Workpiece 1, 10, 10A Clamp 1a First clamp 1b Second clamp 2 rotation Chuck 2A Rotary chuck (for rod-shaped insert material) 2B Rotary chuck (for disc-shaped insert material) 3, 4, 6 Stand 5 Moving means 11 Induction coil 12 Electrode

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Takao Ogawa 1-chome, Mizushima-Kawasaki-dori, Kurashiki-shi, Okayama Pref. Chome (without address) Kawasaki Steel Corporation Mizushima Works F-term (reference) 4E067 AA02 BG00 CA04 DA17 DC05 EC05

Claims (4)

[Claims] 1. A first and a second bar arranged in series are moved in the longitudinal direction of a bar, an insert is inserted between the bars, and the same direction as the first and the second bars is inserted. Characterized in that the insert material is brought into contact with the first and second bars while being rotated while being moved, and the insert and the first and second bars are joined by frictional heat. Method. 2. The first and second bars arranged in series are moved in the longitudinal direction of the bars, an insert is inserted between the bars, and the same direction as the first and second bars is inserted. After the insert material is brought into contact with the first and second bars while rotating to give frictional heat to the contact portion, the insert material is extracted from the position, and the first and second bars are joined. A friction welding method for a rod material. 3. A first and second clamp for respectively restraining first and second rods arranged in series, a rotary chuck for gripping and rotating an insert, and the first and second clamps. And a reciprocating drive means for moving the rotary chuck in the longitudinal direction of the bar;
Moving means for moving in the direction between the bars, and wherein when the moving means moves, the insert material held by the rotary chuck can be inserted between the first and second bars. A friction welding device for a bar material, characterized by the following. 4. A first and second clamp for respectively restraining first and second rods arranged in series, a rotary chuck for supporting and rotating an insert, and the first and second clamps. And a reciprocating drive means for moving the rotary chuck in the longitudinal direction of the bar;
Moving means for moving in the direction between the bars, the moving means inserting the insert material between the first and second bars,
Further, a friction welding apparatus for a rod material having an extracting function.