JP4312988B2 - Thermite welding tool - Google Patents

Description

【００３５】
比較例では点火剤への点火から溶融銅が坩堝から流れ出すまでの時間は、約０.９秒であるのに対し、実施例１および２ではそれより約１秒長かった。そのため、スラグと溶融銅との分離に差が生じる。その結果、表１に示すとおり、実施例１および２では、良好な溶接であったのに対し、比較例１および２では、スラグの巻込み、溶融銅の充填不足、巣の発生が認められ、溶接不良の検体が多くなっている。
【００３６】
なお、図３に示すように、点火薬３４とテルミット溶接誘起薬３３とを充填した耐熱容器３０が蓋２２に取り付けられていてもよい。図３および図４に示すように、坩堝２０や耐熱容器３０には、テルミット剤１８やテルミット溶接誘起薬３３の輸送時の漏洩を防止するキャップ２３・３５を付しておき、図２に示すように、テルミット溶接開始直前にキャップ２３・３５を外してから、溶接を行ってもよい。キャップ２３を外してから坩堝２０を鋳型１０ａ・１０ｂに載置してもよい。
【００３７】
【発明の効果】
以上、詳細に説明したように本発明のテルミット溶接具を用いて溶接すると、溶融金属とスラグとの分離がよく、巣を生じさせることなく金属材同士を溶接することができる。溶接強度は充分に強い。テルミット溶接具は、鋳型が過熱しないので、直ぐに次の溶接に使用でき取り扱い易い。鋳型を繰返し使用できるので、経済的である。さらに溶接作業中にテルミット剤の遺漏や飛散がない。
【図面の簡単な説明】
【図１】本発明を適用するテルミット溶接具の実施例を示す斜視図である。
【図２】本発明を適用するテルミット溶接具の実施例を示す断面図である。
【図３】本発明を適用するテルミット溶接具の別な実施例を示す要部断面図である。
【図４】本発明を適用するテルミット溶接具の別な実施例を示す要部断面図である。
【図５】本発明を適用外のテルミット溶接具の断面図である。
【符号の説明】
１はテルミット溶接具、１０ａ・１０ｂは側部鋳型、１０ｃは底部鋳型、１１・１２は金属材、１３は金属材挿入穴、１４はキャビティ、１５は湯口、１６は開口、１７は熱溶融性部材、１８はテルミット剤、１９は点火剤、２０はセラミックス製坩堝、２１は坩堝填込穴、２２は蓋、２３はキャップ、２４は着火具、２５は留具、２６はクランプ、２７は蝶番、３０は耐熱容器、３１は底穴、３２は熱溶融性部材、３３はテルミット溶接誘起薬、３４は点火薬、３５はキャップ、４０ａ・４０ｂは黒鉛製鋳型、４１・４２は金属材、４４はキャビティ、４５は湯口、４７は熱溶融性ディスク、４８はテルミット剤、４９は点火剤、５０は反応窯である。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a welding tool used for thermite welding of metal materials.
[0002]
[Prior art]
Metal materials such as gas pipes, reinforcing bars, H-shaped steel, rail steel, grounding metal fittings, mesh grounding ground wire, equipment mounting ground wire, rail bond, copper twisted wire, copper strip bus bar, etc. When connecting, thermite welding is performed.
[0003]
Thermite welding is performed by igniting a powdered thermite agent containing a metal oxide such as copper oxide and a reducing agent such as aluminum. An example of a thermite reaction by a thermite agent containing copper oxide and aluminum is as follows. The following chemical reaction formulas (1) and (2)
3Cu0 + 2Al → 3Cu + A1 ₂ 0 ₃ + ΔH (1)
3Cu ₂ + 2Al → 6Cu + A1 ₂ 0 ₃ + ΔH (2)
As shown in FIG. 4, the copper oxide is reduced to become heavy copper, and the resulting reaction heat ΔH melts the copper, while the aluminum is oxidized to become slag mainly composed of light alumina. The molten copper from which the slag is separated due to the difference in specific gravity welds the metal materials together.
[0004]
Conventionally, as shown in FIG. 5, a pair of graphite mold welding tools 40a and 40b, which are face-to-face matched, have been widely used for thermite welding. The butted molds 40a and 40b have a molten copper in which the bottom sprue 45 is closed with a heat-meltable disc 47 and a thermite agent 48 is filled, and the welded portions of the metal materials 41 and 42 are inserted into each other. Has a cavity 44 that flows from the gate 45.
[0005]
When the reaction kiln 50 is made of graphite, the lubricity thereof is high. Therefore, during thermite welding, the separation of the molten copper and the slag mainly composed of alumina or the thermite reaction is insufficient, and the reactants do not stay quickly. To the cavity 44 from the reaction kiln 50. If the reactant flows into the cavity 44 without sufficiently proceeding with the reaction, the heat is suddenly applied to the metal material to be welded, and the molten copper solidifies before the slag or gas rises. In addition, the weld strength is weakened as a result of the formation of a non-uniform and inhomogeneous weld called a nest produced by the generated gas.
[0006]
In order to lower the melting point of the molten copper and increase its fluidity to improve the filling of the molten copper into the cavity 44 and the separation of gas and slag, tin is added to the thermite agent 48 in a ratio of several weight percent. There is. During welding of steel and copper material is a metal material, a portion of the steel material to rise above the A ₁ transformation point, transformed into austenite structure, copper atoms or tin atoms in the grain boundaries of the austenite intrudes Intergranular cracking is likely to occur, and cracks may be induced when repeated stress is applied after welding.
[0007]
Further, as the molds 40a and 40b are repeatedly used, the reaction kiln 50 and the gate 45 are worn by coming into contact with the heat-melting disc 47 or rubbing with a brush to remove slag adhered after welding. . Therefore, since a gap is generated between the disk 47 and the molds 40a and 40b, the powdered thermite agent is leaked, welding becomes insufficient, and the expensive molds 40a and 40b can be repeatedly used only several tens of times. . In addition, when welding outdoors, if powdered thermite agent is thrown into the reaction kiln 50 and is scattered by the wind, welding becomes insufficient.
[0008]
[Problems to be solved by the invention]
The present invention has been made in order to solve the above-mentioned problems, and there is no leakage or scattering of the thermite agent during thermite welding, and the molten metal and the slag are well separated, and the metal materials can be formed without forming a nest. It is an object of the present invention to provide a thermite welding tool capable of repeatedly and simply welding with sufficient strength.
[0009]
[Means for Solving the Problems]
Thermite welding device 1 of the present invention made in order to achieve the object of Figure 1 corresponding to the embodiment, and FIG. 2, will be described with reference to FIGS. 3 and 4, the metal oxide and a reducing agent main agent, a mixture of tin-calcium fluoride, silicide calcium zinc oxide, or thermite agent 18 that contains a melting point depressant and a flux comprising a mixture of calcium fluoride, silicide calcium zinc oxide is accommodated A ceramic crucible 20 for reacting the thermite agent 18 and molds 10a, 10b, and 10c (see FIG. 1) in which metal materials 11 and 12 of a steel material and / or a copper material to be welded are inserted; bottom opening 16 which molten metal flows down from the metal oxides are vacant, the thermite opening 16 is blocked by the heat-fusible member 17 that open onto a sprue 15 of the mold 10a · 10b A contact device,
The thermite agent 18 and the ignition agent 19 are accommodated in the ceramic crucible 20, or
The heat-resistant container 30 is inserted into the lid 22 covering the crucible 20, the bottom hole 31 of the heat-resistant container 30 is closed with the heat-meltable member 32, and the thermite welding inducer 33 having the same composition as the thermite agent 18 is used as the ignition agent. 34 in contact with,
Caps 23 and 35 are attached to the igniting agent 19 or the igniting agent 34 ignited by the ignition tool 24 inserted from the outside .
[0010]
The ceramic crucible 20 is preferably made of alumina, ceramic fiber made of alumina and / or silica, mullite, or cordierite. The ceramic fiber is, for example, a vacuum suction molding material. The molds 10a, 10b, and 10c are preferably made of graphite.
[0011]
The molten metal generated by the progress of the thermite reaction after the thermite agent is ignited in the crucible 20 melts the heat-meltable member 17 and flows down from the opening 16 to the gate 15, and the mold in which the metal materials 11 and 12 are inserted. The cavity 14 is filled and the metal materials 11 and 12 are welded together.
[0012]
If the crucible 20 is made of ceramics, the frictional resistance with the molten metal is large, so that the residence time of the molten metal in the crucible becomes relatively long. As a result, the thermite reaction of the thermite agent proceeds completely, and the expected ΔH As a result, the temperature of the generated molten metal or the like becomes high, and the molten metal produced from the metal oxide and the slag produced as a by-product from the reducing agent are sufficiently separated. Furthermore, since the ceramic crucible 20 has high heat insulation properties, there is little escape of reaction heat, the temperature of the molten metal is less likely to decrease, and the viscosity of the molten metal is maintained low, so that the slag is more easily separated, The molten metal flows sufficiently into the entire cavity 14 and is filled. Since the cooled welded part does not contain slag, it is dense and no nest is generated, and the welding strength is high.
[0013]
The molds 10a, 10b, and 10c are less heated because they do not propagate heat from the highly heat-insulating crucible, can be used for subsequent welding, and are easy to handle. Expensive graphite molds 10a, 10b, and 10c can be used repeatedly several hundred times and are economical.
[0014]
The inexpensive ceramic crucible 20 is replaced every time it is welded because a part of the separated slag is sintered with the ceramic surface and cannot be scraped off with a brush or the like.
[0015]
The thermite agent 18 includes, for example, copper oxide and iron oxide as the metal oxide, and includes, for example, Al, P, Si, Ca, Mg, Ti, Be , and a copper-aluminum alloy as the reducing agent. For example, tin, calcium fluoride, cryolite, calcium halide, zinc oxide or the like may be added to the thermite agent 18 as a melting point depressant and a flux. If the crucible 20 is used, the viscosity of the molten metal is lowered and the slag is easily separated. Therefore, it is not necessary to add tin or the like that easily causes grain boundary cracking of the steel material to the thermite agent 18.
[0016]
It is preferable that the thermite agent 18 and the igniter 19 in contact therewith are packed. If it is filled, the thermite agent 18 will not leak from the crucible and will not be scattered by the wind.
[0017]
As shown in FIG. 3, the thermite welding tool 1 has a heat-resistant container 30 inserted into a lid 22 covering the crucible 20, and a bottom hole 31 of the heat-resistant container 30 is closed with a heat-meltable member 32. The thermite welding inducer 33 having the same composition may be filled in contact with the igniting agent 34. The thermite welding inducing agent 33 reacts by igniting the igniting agent 34 in the heat-resistant container 30, and the generated molten metal hangs down on the thermite agent 18 in the crucible 20 to induce the thermite reaction.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Below, the example of thermite welding tool 1 to which the present invention is applied is described in detail.
[0019]
FIG. 1 is an external perspective view showing an embodiment of the thermite welding tool 1. FIG. 2 is a cross-sectional view taken along the line AA.
[0020]
As shown in FIG. 1, the thermite welding tool 1 has graphite molds 10 a, 10 b, and 10 c at a lower portion, and a ceramic crucible 20 is placed on the upper portion.
[0021]
In this mold, two side molds 10a and 10b made of graphite for contrast are placed on the bottom mold 10c. A hinge 27 (see FIG. 2) is attached to the side molds 10a and 10b. One side mold 10a and the bottom mold 10c are fixed by a clamp 26 so as not to be separated. The other side mold 10 b can be opened and closed by a hinge 27 and is fastened so as not to be opened by a fastener 25. A ceramic crucible 20 is placed on the two side molds 10a and 10b that are butted together. A lid 22 covers the crucible 20.
[0022]
As shown in FIG. 2, the opening 16 in the bottom of the crucible 20 is closed with a hot-melt member 17. The crucible 20 is filled with a thermite agent 18 containing copper oxide and aluminum, and an igniting agent 19 coated thereon.
[0023]
The contact surface between the upper surface of the bottom mold 10c and the lower surfaces of the side molds 10a and 10b has a margin of two copper strands 11 and one copper strand 12 which are metal materials to be thermite welded. To form a metal material insertion hole 13 to be inserted from the left and right, and a cavity 14 connected to the insertion hole 13 and having a larger diameter and welding the welded portion of the copper strands 11 and 12 with molten metal. A groove is provided.
[0024]
A half body of a hole for forming a crucible filling hole 21 for filling the crucible 20 and a gate 15 for conducting from the crucible filling hole 21 to the cavity 14 are formed on the surface where the side molds 10a and 10b are abutted. A groove is provided.
[0025]
When the side molds 10a and 10b are put on the bottom mold 10c while abutting each other, the metal material insertion hole 13, the cavity 14, the gate 15, and the crucible filling hole 21 are formed.
[0026]
The copper strands 11 and 12 are inserted from the left and right metal agent insertion holes 13, respectively, and the welded portions of the copper strands 11 and 12 are pushed into the cavity 14.
[0027]
The metal materials 11 and 12 are thermite welded as follows.
[0028]
When the igniter 19 is ignited by the ignition tool 24, the thermite reaction of the thermit agent 18 is induced, and molten copper that is a molten metal and slag mainly composed of alumina are generated. Slag with a low specific gravity floats from the molten copper, while molten copper with a high specific gravity sinks. The molten copper separated from the slag finally melts the heat-meltable member 17 by the heat and flows out from the opening 16. This molten copper flows into the cavity 14 through the gate 15 and is filled without any gaps, melts the both end faces of the welded portions of the copper wires 11 and 12, and solidifies and bonds the both ends together in a molecular manner. The side molds 10a and 10b and the bottom mold 10c are peeled off, and after the post-treatment of scraping the slag adhering to the side molds 10a and 10b and the bottom mold 10c with a waste cloth or a brush, similar welding is repeated.
[0029]
Examples of thermite welding using the thermite welding tool to which the present invention is applied according to the above-described example are shown in the following examples 1 and 2, and an example of the present invention using the thermite welding tool not applied to the present invention is comparative example 1. And shown in 2.
[0030]
Example 1
The ceramic crucible 20 was a cordierite cylinder having a height of 60 mm and an outer diameter of 62 mm, an upper edge having an inner diameter of 50 mm, and an opening 16 having a diameter of 12 mm at the bottom. An iron disk 17 having a thickness of 0.3 mm was used as a heat-meltable member for closing the opening 16. The thermite agent 18 is a mixture of copper oxide and a copper-aluminum alloy as main components and tin, calcium fluoride, calcium halide, and zinc oxide as melting point depressants and fluxes, and together with an igniter coated thereon. The one that was packed was used. The molds 10a, 10b, and 10c are made of graphite having a rectangular parallelepiped shape having an outer width of 80 mm, a height of 200 mm, and a depth of 80 mm. The crushed side molds 10a and 10b are provided with crucible insertion holes 21 having a diameter of 64 mm and a depth of 60 mm. Metallic materials to be welded is a line 12 from one of copper cross-sectional area 55 mm ² of the two lines 11 and the cross-sectional area of copper 115 mm ^2. Thermite welding was performed 5 times in succession.
[0031]
(Example 2)
Thermite welding was performed in the same manner as in Example 1 except that a thermite agent containing no tin was used.
[0032]
(Comparative Examples 1 and 2)
Instead of the thermite welding tool having a ceramic crucible, thermite welding was performed in the same manner as in Examples 1 and 2 except that a graphite welding tool as shown in FIG. 5 was used.
[0033]
The appearance of the welded parts of each of the five specimens obtained by thermite welding was observed, and the presence or absence of slag mainly composed of alumina was examined and the lack of filling of the molten copper into the cavity was investigated. Also, the welded part was cut with a high-speed rotating cutter and examined for the presence of nests. The results are shown in Table 1.
[0034]
[Table 1]

[0035]
In the comparative example, the time from the ignition of the igniter to the molten copper flowing out of the crucible was about 0.9 seconds, while in Examples 1 and 2, it was about 1 second longer than that. For this reason, a difference occurs in the separation between the slag and the molten copper. As a result, as shown in Table 1, in Examples 1 and 2, good welding was achieved, but in Comparative Examples 1 and 2, slag entrainment, insufficient filling of molten copper, and formation of nests were observed. There are many specimens with poor welding.
[0036]
As shown in FIG. 3, a heat-resistant container 30 filled with the ignition agent 34 and the thermite welding induction agent 33 may be attached to the lid 22. As shown in FIGS. 3 and 4, the crucible 20 and the heat-resistant container 30 are provided with caps 23 and 35 for preventing leakage of the thermite agent 18 and the thermite welding inducer 33 during transportation, as shown in FIG. Thus , welding may be performed after removing the caps 23 and 35 just before the start of thermite welding. The crucible 20 may be placed on the molds 10a and 10b after the cap 23 is removed.
[0037]
【The invention's effect】
As described above in detail, when welding is performed using the thermite welding tool of the present invention, the molten metal and the slag are well separated, and the metal materials can be welded together without forming a nest. The welding strength is sufficiently strong. Since the mold does not overheat, the thermite welding tool can be used for the next welding immediately and is easy to handle. Since the mold can be used repeatedly, it is economical. Furthermore, there is no leakage or scattering of thermite agent during the welding operation.
[Brief description of the drawings]
FIG. 1 is a perspective view showing an embodiment of a thermite welding tool to which the present invention is applied.
FIG. 2 is a cross-sectional view showing an embodiment of a thermite welding tool to which the present invention is applied.
FIG. 3 is a cross-sectional view of an essential part showing another embodiment of the thermite welding tool to which the present invention is applied.
FIG. 4 is a cross-sectional view of an essential part showing another embodiment of the thermite welding tool to which the present invention is applied.
FIG. 5 is a cross-sectional view of a thermite welding tool to which the present invention is not applied.
[Explanation of symbols]
1 is a thermite welding tool, 10a and 10b are side molds, 10c is a bottom mold, 11 and 12 are metal materials, 13 is a metal material insertion hole, 14 is a cavity, 15 is a sprue, 16 is an opening, and 17 is heat melting Member, 18 is a thermite agent, 19 is an igniter , 20 is a ceramic crucible, 21 is a crucible filling hole, 22 is a lid, 23 is a cap, 24 is an ignition tool, 25 is a fastener, 26 is a clamp, 27 is a hinge , 30 is a heat-resistant container, 31 is a bottom hole, 32 is a heat-meltable member, 33 is a thermite welding inducer, 34 is an ignition agent, 35 is a cap, 40a and 40b are graphite molds, 41 and 42 are metal materials, 44 Is a cavity, 45 is a sprue, 47 is a hot-melt disk, 48 is a thermite agent, 49 is an ignition agent, and 50 is a reaction kiln.

Claims (4)

Main agent of a metal oxide and a reducing agent, that contains a mixture of tin-calcium fluoride, silicide calcium zinc oxide, or a melting point depressant which comprises a mixture of calcium fluoride, silicide calcium zinc oxide and flux A ceramic crucible containing a thermite agent and reacting with the thermit agent, and a mold in which a steel material and / or a copper metal material to be welded are inserted, derived from the metal oxide at the bottom of the crucible and Ai openings molten metal flows down has openings which is blocked by the heat-fusible member is a thermite welding device that open onto the sprue of the mold,
The thermite agent and igniter are contained in the ceramic crucible, or
A heat-resistant container is inserted into the lid covering the crucible, the bottom hole of the heat-resistant container is closed with a heat-meltable member, and a thermite welding inducer having the same composition as the thermit agent is filled in contact with the ignition agent Has been
A thermite welding tool characterized in that a cap is attached to the ignition agent or the ignition agent that is ignited by an ignition tool inserted from the outside .     The thermite welding according to claim 1, wherein the ceramic crucible is made of alumina, ceramic fiber made of alumina and / or silica, mullite, or cordierite, and the mold is made of graphite. Ingredients. Thermite welding device according to claim 1 and said thermite material, and said igniter which is in contact on it is characterized in that it is圧填. The thermite agent includes the metal oxide selected from copper oxide and iron oxide, the reducing agent selected from Al, P, Si, Ca, Mg, Ti, Be, and a copper-aluminum alloy, and cryolite. The thermite welding tool according to claim 1 , comprising the melting point depressant and a flux .

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