JPH1085956A - Butt joining method of metal tube or metal rod - Google Patents

Abstract

(57) [Problem] In a method of joining metal tubes or metal rods in the length direction and performing diffusion joining by interposing an insert metal at a joint surface of both materials, the two materials are not shifted during joining.
After the butt, they are joined so as not to slide in the lateral direction. SOLUTION: By bridging a plurality of rod-shaped supports 6 on a joint surface 4, both materials are locked in a lateral direction. Protrusions 9 are provided at a plurality of locations in the circumferential direction on one of the joining surfaces 4 of the metal tubes, and the other side is provided with a recess 10 that fits into the protrusions 9, thereby locking in the lateral direction. Protrusions 9 are provided on one of the joining surfaces of the metal rods, and recesses 10 that fit into the protrusions 9 are provided on the other, so that the metal bars are locked in the lateral direction. [Effect] Very good diffusion bonding can be performed with a simple configuration. It is cheaper and easier than other joining means such as MIG welding, TIG welding, pressure welding, etc., and is suitable for on-site construction of oil country tubular goods or joining of steel pipes, steel rods, and the like at various construction sites.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of joining metal tubes or metal rods in the longitudinal direction, and inserting an insert metal into a joining surface of the two materials to perform diffusion joining. Also, the present invention relates to a method for joining without joining in the lateral direction after butting.

[0002]

2. Description of the Related Art As a means for joining metal materials, an insert metal made of an amorphous metal foil is interposed between the joining surfaces of the two materials to be joined, and the element contained in the metal is heated by applying pressure. There is a diffusion bonding method for diffusing in. In this diffusion bonding method, since the amorphous metal element in the insert metal is easily diffused, bonding can be performed by heating for a relatively short time, and it is possible even in the air. Therefore, it is attracting attention as an inexpensive and simple joining means that replaces MIG welding and TIG welding in on-site construction of oil well steel pipes and the like.

The present inventors have proposed in Japanese Patent Application Laid-Open No. 5-123890, for a butt-joining insert metal such as a steel pipe, a brazing material for a truncated conical ring made of rapidly solidified foil and a method for producing the same. When the joining method using the frusto-conical ring is shown, as shown in FIG. 12, the end faces of the pipes 1 and 2 to be joined are processed, and one pipe 1 has a concave taper and the other pipe 2 has a concave taper. A convex taper is formed, and a frustoconical ring-shaped insert metal 3 is interposed between the two tapers to heat under pressure.

Japanese Patent Application Laid-Open No. 55-73488 discloses a butt-welding method for aluminum pipes, in which one pipe end face is formed in a wedge shape, and the other pipe end face is formed into a recessed shape that engages with this, or both are formed in an intaglio manner. There is disclosed a method in which a powdery or foil-like metal which is formed into an intermeshed shape and which forms a eutectic melt at a relatively low temperature by causing an eutectic reaction with aluminum is put in a recess and engaged.

[0005]

In the butt diffusion bonding method of a metal pipe or a metal rod in which an insert metal is interposed as described above, both materials are butt-joined on a bonding surface without displacement, and after butt-joining, they are laterally aligned. It is necessary to avoid slipping in the direction. This is because, if it is displaced at the time of butting or slips after butting, problems such as a decrease in the contact area with the insert metal, a decrease in the area of the joining surface and a decrease in joining strength are caused.

In Japanese Patent Laid-Open No. 5-123890, concave and convex tapers formed on the end faces of both pipes to be joined are fitted, but they have not yet sufficiently prevented slippage and slippage. In addition, as described in
The wedge type or the inro type disclosed in Japanese Unexamined Patent Publication No. 5-73488 is provided with a step having a large wall thickness over the entire circumference of the pipe. Time lag cannot be sufficiently prevented.

The present invention relates to a method of joining metal tubes or metal rods in the length direction and performing diffusion joining by interposing an insert metal at a joining surface of the two materials so that the two materials are not displaced at the time of joining and after joining. It aims to obtain sufficient bonding strength by bonding without slipping in the lateral direction.

[0008]

According to a first aspect of the present invention, a metal tube or a metal rod is butt-bonded in a longitudinal direction, an insert metal is interposed at a joint surface between both materials, and a metal pipe is inserted. In the method of diffusion bonding by heating while pressing,
A method for butt-joining metal tubes or metal rods, wherein a plurality of rod-shaped supports are hung over the joint surface to lock the two materials laterally. Further, by providing a convex portion on one of the joining surfaces of the two materials and providing a concave portion fitted to the convex portion on the other, the two materials can be locked in the lateral direction.

A second invention method is a method of joining metal tubes in the longitudinal direction, interposing an insert metal at a joining surface of both materials, and applying heat while applying pressure to perform diffusion joining, wherein one of the joining surfaces is convex. A metal pipe butt joining method characterized in that a plurality of portions are provided in a plurality of positions in a circumferential direction, and the other is provided with a concave portion that fits into the convex portion, thereby locking the two materials in the lateral direction.

A third invention method is a method of performing diffusion bonding by joining metal rods in the longitudinal direction, inserting an insert metal into a joining surface of the two materials, and heating while applying pressure, wherein one of the joining surfaces is convex. A metal rod butt-joining method characterized by providing a portion and a concave portion fitted to the convex portion on the other side to lock the two materials in the lateral direction.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The method of the present invention will be described with reference to an example shown in the drawings. FIG. 1 shows an example of a method for joining pipes according to the first invention method. Each joint surface 4 of the pipes 1 and 2 is perpendicular to the pipe axis, and is provided with a plurality (two in FIG. 1) of holes 5. A rod-shaped support 6 is buried in the hole 5 of one of the tubes (the tube 2 in FIG. 1) in the length direction about 1/2, and one or both of the tube 1 and the tube 2 are moved to the other tube (the tube 2). By inserting the rod-shaped support 6 into the hole 5 of the tube 1), the rod-shaped support 6 is hung over the joint surface 4 and abutted. At this time, an insert metal 3 is interposed between the two joining surfaces 4 and 4. After the butting, the two tubes 1 and 2 are heated while being pressurized to perform diffusion bonding.

FIG. 2 shows an example in which the joint surface 4 of both pipes is inclined. The pipe 1 is provided with a convex taper and the pipe 2 is provided with a concave taper to increase the area of the joint surface 4 and at the time of abutting. The displacement and the slip after butting are suppressed. Others are the same as the example of FIG. In the example of FIG. 1 and FIG. 2, a plurality of rod-shaped supports 6 are laid over the joining surface and the lateral movement of both tubes 1 and 2 is locked, so that there is no risk of displacement at the time of abutment, and slipping occurs after the abutment. There is no fear.

In the examples shown in FIGS. 1 and 2, the rod-shaped support 6 may be inserted into the pipe 1 side and the pipe 2 side from the joint surface 4 by about 10 mm, and the cross-sectional shape may be arbitrary. Further, an insert metal can be wound around the rod-shaped support 6. The insert metal 3 is formed of a rapidly solidified foil containing an amorphous material, has a shape conforming to the joining surface, and has a hole formed in advance at the position of the rod-shaped support 6.

In the example shown in FIG. 3, the rod-shaped support 6 is extended over the joint surface 4 along the outer peripheral surfaces of the tubes 1 and 2.
In this example, the rod-shaped support 6 is fixed to the pipe 1 by spot welding, and 7 is a welded portion. Thus, the rod-shaped support 6
Is provided along the outer peripheral surface, the two pipes 1, 2
3 or more are required to lock the lateral movement over 360 °. However, even with two rod-shaped supports 6,
As shown in FIG. 4, which is a view taken in the direction of arrow AA in FIG. 3, if it is formed in an arc shape along the outer periphery, it can be locked over 360 °.

At the time of abutting, the rod-shaped support 6 is fixed to one of the tubes (the tube 1 in FIG. 3), and one or both of the tubes 1 and 2 are moved so that the two joining surfaces are joined with the insert metal 3. Intervene and collide. After the butting, the two tubes 1 and 2 are heated while being pressurized to perform diffusion bonding. Note that the welded rod-shaped support 6 may be removed after the two tubes 1 and 2 are joined, or may be left attached if there is no problem.

In the example shown in FIG. 5, the rod-shaped support 6 extends along the inner peripheral surfaces of both tubes 1 and 2 and is joined to the joint surface 4.
In this embodiment, the rod-shaped support 6 is fixed to the tube 1 by a magnet 8. When the rod-shaped supports 6 are provided along the inner peripheral surface as described above, even two rod-shaped supports 6 can be locked over 360 °, but in the case of two rod-shaped supports 6, it is preferable to form an arc along the inner periphery. In this example, the pipe end is processed, and the pipe 1 has a convex taper,
The pipe 2 is provided with a concave taper to incline the joining surface. The butting can be performed in the same manner as in the example of FIG.

The fixing of the rod-shaped support 6 by the magnet 8 can be applied to the example shown in FIG. When the two tubes 1 and 2 are joined to each other and heated to a temperature equal to or higher than the Curie point, the magnet 8 becomes paramagnetic, so that the magnet 8 can be easily removed from the tube 1 and falls naturally when joined vertically. . Generally, the Curie point of the magnet 8 is about 700 to 800 ° C., although it depends on the composition of the alloy.

Each of the examples shown in FIGS. 1 to 4 can also be applied when the target material is a metal rod. Metal rods having various cross-sectional shapes such as round rods and square rods can be used. In the example of FIG. 6, holes 5 are respectively formed in the joint surfaces 4 of the rods 11 and 12, and a plurality of rod-like supports 6 (two are visible in FIG. 6) are inserted into the joint surfaces 4. And hang it over. At this time, the insert metal 3 is interposed between the two joining surfaces 4 and 4. A hole is made in the insert metal 3 at the position of the bar-shaped support 6.

In the example shown in FIG. 7, the rod-shaped support 6 is extended over the joint surface 4 along the peripheral surfaces of the rods 11 and 12. In this embodiment, the rod-shaped support 6 is fixed by the magnet 8, but it can be fixed by welding. Also in the example of FIG. 7, similarly to the example of FIG. 3, when the number of the rod-shaped supports 6 is two, the shape is an arc along the peripheral surface.

Next, in the first invention method, the second method described later
The invention method can be applied together. Examples are shown in FIG. 8 and FIG. FIG. 8 is a longitudinal sectional view, and FIG. 9 is AA of FIG.
It is arrow sectional drawing. Two rod-shaped supports 6 are laid over the joint surface 4 of the pipes 1 and 2, and a convex portion 9 is provided on the joint surface 4 of the tube 2, and the convex portion 9 is fitted on the joint surface 4 of the tube 1. By providing the corresponding concave portion 10, the two tubes 1 and 2 are locked in the lateral direction.

By locking the rod-shaped support 6 with both the projections 9 and the recesses 10 as described above, it is possible to more effectively prevent displacement of the two tubes 1 and 2 at the time of abutment and slippage after the abutment. Can be. Although the magnet 8 is used in this embodiment as a means for fixing the rod-shaped support 6, welding may be used. Further, the rod-shaped support 6 may be fixed to the inner peripheral surface of the tube. Further, the numbers of the convex portions 9 and the concave portions 10 are not limited to this example, and may be arbitrary. In addition, metal rods can be used as a target and similarly butted and joined.

The second invention method is directed to a metal tube,
As in the case where the rod-shaped support 6 is removed in FIGS. 8 and 9, the circumferential direction 2
A convex portion 9 is provided at a location, and a concave portion 10 that fits into the convex portion 9 is provided on the other tube 1.
Is locked laterally. The convex portion 9 and the concave portion 10 are not limited to this example, and the pipes 1 and 2 may be provided at arbitrary plural places so that the two pipes 1 and 2 are horizontally locked over 360 ° at the joint surface. Then, the insert metal 3 is interposed between the two joining surfaces 4 to butt and is heated while being pressurized to perform diffusion bonding.

The example of FIG. 10 shows a cross section similar to that of FIG. 9, and a projection 9 is provided at a part of the wall thickness of the pipe 2 at three locations in the circumferential direction. In these examples of FIGS. 8 to 10, the insert metal 3 is fixed in accordance with the unevenness of the joint surface 4. At that time, a foil cut in accordance with the shape of each part may be adhered, or a foil having a shape conforming to the unevenness of the joining surface may be directly cast from a molten metal to produce and adhere. The bonding is not limited to the second invention, and may be performed via an adhesive substance in each of the methods of the present invention, and an insert metal made of a magnetic material may be magnetically attached.

The third invention is directed to a metal rod.
An example is shown in FIG. FIG. 11 shows a cross section similar to that of the example of FIG. 9, in which one bar (bar 12 in the figure) of the joint surface 4 is provided with a convex portion 9 and the other bar 11 (not shown) is provided with a convex portion 9. The two rods are locked in the lateral direction by providing a fitting recess and fitting the two. The shape of the protrusion 9 is shown in FIG.
As shown in each of the drawings (b), (c), and (d), the shape is such that the joint surface is laterally locked over 360 °. Then, the insert metal 3 is interposed between the two joining surfaces 4 to butt and is heated while being pressurized to perform diffusion bonding. Metal rods having various cross-sectional shapes such as round rods and square rods can be used.

[0025]

【Example】

Invention Example-1 (First Invention Method): Steel pipes were diffusion-bonded by the method of the present invention. For steel pipes, ST specified in JIS G 3444
K400, outer diameter 264.4 mm, inner diameter 228.8 mm, wall thickness 17.8 mm. As shown in FIG. 1, a diameter 6 mmφ and a depth 15
A hole 5 of mm was drilled. As the insert metal 3, an amorphous alloy foil having a composition of 30 μm thick Fe-9 wt% Si-1.5 wt% B is adopted, and a hole is formed at the position of the hole 5 according to the shape and dimensions of the joining surface 4. The adhesive was attached to the joint surface 4 of the tube 2.

A round steel bar having a diameter of 5.6 mm and a length of 29 mm was inserted as a rod-shaped support 6 into the two holes of the tube 2. The round steel bar is SS400 specified in JIS G 3192. Then, the rod-shaped support 6 is inserted into the hole 5 of the joint surface 4 of the pipe 1 from the other end, and the two joint surfaces 4 are brought into close contact with each other via the insert metal 3. did. The heating rate during heating is about 5 ° C.
After reaching ℃, the temperature was held for 5 minutes, and the power was turned off to cool.

Invention Example-2 (First Invention Method): Invention Example-
The same steel pipe as No. 1 was butted and diffusion bonded as shown in FIG. 3 with the same insert metal intervening. Four round steel rods of the same steel type as in the above example and having the same diameter and a length of 50 mm were fixed to the outer peripheral surface of the steel pipe on one side by welding at intervals of 1/4 circumference. Then, the other steel pipe is inserted into the interior surrounded by the round steel rods using the four round steel rods as guides,
Both joining surfaces 4 were brought into close contact with each other via the insert metal 3, and were pressed and heated under the same conditions as in the above example.

Invention Example-3 (second invention method): Invention Example-
Insert the same steel pipe as in 1 with the same insert metal,
8 and 9, butted and diffusion-bonded by the method except for the rod-shaped support 6. As shown in FIG. 8, an insert metal 3 having a shape conforming to the joint surface 4 of the tube 2 was attached to the entire surface. Note that the sticking was omitted on the side surface of the convex portion 9.

Invention Example-4 (Third Invention Method): The steel bars were diffusion bonded by the method of the present invention. The bar is SS400 specified in JIS G 3192 and has a diameter of 22 mm. As shown in FIG. 6, holes 5 having a diameter of 2 mm and a depth of 10 mm were drilled at two target positions 3 mm from the outer periphery of both rods 11 and 12. As the insert metal 3, a 30 μm thick Fe
An amorphous alloy foil having a composition of -9 wt% Si-1.5 wt% B is used, and a hole made at the position of the hole 5 is formed on the joint surface 4 of the rod 12 according to the shape and dimensions of the joint surface 4. Pasted.

A round steel rod having a diameter of 1.8 mm and a length of 19 mm was inserted as a rod-shaped support 6 into the two holes of the rod 12. The round steel bar is SS400 specified in JIS G 3192. Then, the rod-shaped support 6 is inserted into the hole 5 of the joint surface 4 of the rod 11 from the other end, and the two joint surfaces 4 are brought into close contact with each other via the insert metal 3, pressurized at about 40 kg, and heated at the joint by a high frequency induction method. did. The heating rate during heating is about 5 ° C.
After reaching 0 ° C., the temperature was held for 5 minutes, and the power was turned off to cool.

Conventional Example: The same steel pipe as in Example 1 of the present invention was butted and diffusion-bonded as shown in FIG. The taper angle α of both tubes 1 and 2 is 45 °
It is. The pressure and heating conditions after the butting are the same as in the above example.

As a result of observing the joints of each of the examples of the present invention and the conventional example in detail, no step was found in any of the examples of the present invention, and high-precision butt joining was performed. On the other hand, in the conventional example, a slight level difference was recognized, and it was found that a displacement at the time of abutment or a slip after the abutment occurred.

Further, as a result of taking a tensile test piece having the joint substantially at the center and conducting a tensile test, all of the examples of the present invention break at the base material, and the strength and toughness of the joint are reduced as structural members. That was enough. However, in the conventional example, a break was observed in a part of the joint, and it was found that the joint had a defect.

[0034]

According to the method of the present invention, in a method in which a metal tube or a metal rod is butted in the longitudinal direction, and insert metal is interposed in a joining surface of the two materials and diffusion bonding is performed, there is a possibility that the two materials may be displaced during the butting. Since there is no risk of sliding in the horizontal direction after the butting, there is no step at the joint.
Then, since the entire surface of the bonding surface is in close contact via the insert metal, mechanical properties such as strength and toughness of the bonding portion are extremely good.

Excitation and joining can be performed by a device having a relatively simple structure, and it is cheaper and easier than other joining means such as MIG welding, TIG welding, or pressure welding. Alternatively, it is suitable for joining steel pipes, steel bars, and the like in various construction sites.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an example of the present invention.

FIG. 2 is a longitudinal sectional view showing another example of the present invention.

FIG. 3 is a longitudinal sectional view showing another example of the present invention.

FIG. 4 is a sectional view taken along the line AA of FIG. 3 showing another example of the present invention.

FIG. 5 is a longitudinal sectional view showing another example of the present invention.

FIG. 6 is a longitudinal sectional view showing another example of the present invention.

FIG. 7 is a longitudinal sectional view showing another example of the present invention.

FIG. 8 is a longitudinal sectional view showing another example of the present invention.

FIG. 9 is a cross-sectional view taken along the line AA of FIG. 8, showing another example of the present invention.

FIG. 10 is a cross-sectional view showing another example of the present invention.

FIGS. 11A, 11B, 11C, and 11D are cross-sectional views showing another example of the present invention.

FIG. 12 is an explanatory view of a conventional method in which metal tubes are diffusion-bonded with an insert metal interposed therebetween.

[Explanation of symbols]

 1, 2, pipe 3, insert metal 4, joint surface 5, hole 6, rod-like support 7, welded part 8, magnet 9, convex part 10, concave part 11, 12, rod

 ──────────────────────────────────────────────────の Continued on the front page (72) Eiji Tsuru, Inventor 20-1 Shintomi, Futtsu-shi, Chiba Nippon Steel Corporation Technology Development Division

Claims (4)

[Claims] In a method of joining metal tubes or metal rods in the longitudinal direction, insert metal intervening at a joining surface of both materials, and applying heat while applying pressure to perform diffusion joining, a plurality of rod-shaped supports are joined together. A butt-joining method for a metal pipe or a metal rod, wherein the two materials are laterally locked by being hung over a surface. 2. A projection is provided on one of the joining surfaces of the two materials,
2. The method as claimed in claim 1, wherein the other material is provided with a concave portion which fits into the convex portion, thereby locking the two materials in the lateral direction. 3. A method in which metal tubes are joined in the longitudinal direction, an insert metal is interposed between joining surfaces of both materials, and the joining is performed by pressurizing and heating to perform diffusion joining. A butt joint method for metal pipes, wherein the two materials are provided in a plurality of locations, and the other is provided with a concave portion that fits into the convex portion, thereby locking the two materials in the lateral direction. 4. A method in which metal rods are butted in the length direction, insert metal is interposed in a joining surface of the two materials, and the two members are joined by diffusion while heating while applying pressure. The other end is provided with a concave portion fitted to the convex portion, thereby locking the two materials in the lateral direction.