JP2857116B2 - Automatic welding support - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a support for automatic welding, and more particularly, to a support for automatic welding in which a glass fiber body is laminated on a base material surface as a base material auxiliary tool and the material of the base material is improved.

[0002]

2. Description of the Related Art Generally, automatic welding is performed at a high current (850 to 850).
1,250 A), which is a welding method performed at a high voltage, and it is desirable that the base material of the ceramic welding support has excellent heat resistance and thermal shock resistance.

[0003] However, the solid flux which has been used as a conventional support for automatic arc welding, which is obtained by covering a phenolic resin with a casting sand and thermally hardening it at a low temperature of about 180 ° C, has a high heat during welding (about 1,550). (Approx. ° C.), the phenol resin covering the molding sand of the support tool has a disadvantage that it is completely decomposed and burned.

[0004] The foundry sand which has lost the bonding force thereby causes a large amount of dust after welding, and a magnetic clamp 2a as shown in Fig. 2 is used to attach a solid flux to a steel sheet. This leads to poor working conditions, which leads to lower productivity and higher costs.

Since the shape of the solid flux is completely standardized to a length (EA) of 600 mm per piece,
It cannot be applied to parts where welding is difficult, such as curved surfaces.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to provide an automatic welding support which does not generate dust, does not use a magnetic clamp, and is capable of welding a curved surface portion.

[0007]

Automatic welding support of the present invention According to an aspect of the 70 to 95% by weight of SiO _2, 2 to 15 wt% of Al ₂ 0 _3, 1 to 5 wt% of MgO, 1.2 ~ 8% by weight
Na ₂ O and / or K ₂ O and 0.01 to 0.5
A ceramic base material having a porosity of 25 to 48% and a fire resistance of 1,435 to 1,670 ° C, containing 40% by weight of water, and 40 to 70% by weight of SiO ₂ ,
20 wt% of Al ₂ O _3, 3~15 wt% B ₂ O _3,
Comprising 8 to 28% by weight of CaO, 0.5 to 4% by weight of an alkali metal oxide and 0.01 to 0.5% by weight of water;
It is characterized by containing a glass fiber body having a thickness of 0.3 to 1.5 mm.

Further, in the support for automatic welding according to the present invention, the base material may contain quartz, tridymite and / or cristobalite.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS SiO ₂ which is a main component of the ceramic base material according to the present invention contains 70 to 95% in the ceramic base material.
% By weight. The reason specified in this range is that if the content is less than 70% by weight, heat resistance is reduced, excessive slag is generated to form an inner bead, and since there is a large amount of dissolved material, arc heat becomes unstable, and the undercut and sputtering are performed. Melting point defects are caused, and when the content exceeds 95% by weight, the fluidity of the slag is reduced, so that a uniform inner bead cannot be formed, the removability of the slag is reduced, and the slag winding phenomenon occurs. .

Next, the content of Al ₂ O ₃ contained in the ceramic base material according to the present invention increases the fire resistance of the ceramic base material so that it can withstand high heat during automatic welding, and is generated during welding. The range is from 2 to 15% by weight to increase the viscosity of the slag and to have a uniform back bead. The reason defined in this range is that if the content is less than 2% by weight, the slag peelability is weak, and it is necessary to perform back gouging after welding.
If the content is more than 5% by weight, the fire resistance becomes too high, the viscosity of the slag becomes low, the undercut which is a slag winding phenomenon occurs, and welding defects such as sputtering and overlap also occur. .

Further, MgO contained in the ceramic base material according to the present invention is a component functionally similar to Al ₂ O _3, and enhances the heat resistance of the ceramic base material and improves the thinness of the slag. It is a component that does. Here, the content of MgO is 1 to
5% by weight, and the reason specified in this range is 1% by weight.
If it is less than 5%, the viscosity of the molten metal becomes low, and the slag removability decreases, and a large amount of undercut and overlap occur. If it exceeds 5% by weight, the viscosity of the molten metal becomes excessive and gas release becomes difficult. This is because welding defects such as flow fall, sputtering, and dents are caused.

Next, Na ₂ O or K ₂ O contained in the ceramic base material according to the present invention is a component that has a flux function and a function of expanding the plastic range of the ceramic base material in the ceramic base material. Here, the content of Na ₂ O or K ₂ O is 1.
2 to 8% by weight, and the reason specified in this range is as follows.
If the content is less than 2% by weight, the viscosity of the slag becomes low, the slag peeling property is lacking, and the generated inner bead is wrapped, that is, a large amount of undercut occurs. This is because the base material is vitrified to reduce the thermal shock resistance during rapid heating and rapid cooling.

The moisture contained in the ceramic base material according to the present invention is 0.01 to 0.5% by weight, but the reason specified in this range is that the water content of the ceramic base material at the time of welding is limited. This is because it has a great effect on the flow holes and depressions. If moisture exceeding 0.5% by weight is present in the ceramic base material, the molten metal absorbs moisture from the ceramic base material instantaneously during welding and backs up. This is because a large amount of fine pores are generated in the bead. The moisture is present on the surface of the ceramic base material and in the pores by absorbing moisture in the atmosphere.

Next, the porosity of the ceramic base material according to the present invention is 25 to 48%. By defining this range, the thermal shock resistance due to rapid heating and rapid cooling of the ceramic base material increases, and it is possible to support the molten metal without damaging the ceramic base material particularly during welding. When the porosity is less than 25%, the ceramic base material is too dense and the ceramic vitrifies, gas is not easily released, and the ceramic is liable to be damaged by thermal shock. There is a possibility that the mechanical strength of the material is reduced and the material is damaged by an external impact, and absorbs moisture existing in the atmosphere to form fine pores in the back bead during welding. The porosity is defined by the following equation. Porosity = (W ₃ −W ₁ ) / (W ₃ −W ₂ ) × 100 (W ₁ : dry weight, W ₂ : water weight, W ₃ : saturated water weight when pulled up from water)

The fire resistance of the ceramic base material according to the present invention is as follows:
1,435 to 1,670 ° C (SK15 to 30). Generally, automatic welding is performed at a high temperature of about 1,550 ° C. However, in the case of a fire resistance of 1,435 ° C or less (SK15) or less, slag is excessively generated and ceramic components penetrate into the molten metal. Although the purity of the welded steel is reduced due to this, on the other hand, in the case of a fire resistance of 1,670 ° C. (SK30) or more, the generation of slag is suppressed too much and the ceramic base material sticks to the slag after welding and peels off from the steel. This is because, for that purpose, it is necessary to perform double work called back gouging.

In addition, the ceramic base material according to the present invention comprises:
_{Fe 2 O 3, TiO 2,} Li 2 O, CaO, 1 or more may contain 0.5 to 5 wt% of a metal oxide such as ZrO ₂ and the like.

The glass fiber according to the present invention contains SiO ₂ and its content is 40 to 70% by weight. The reason specified in this range is that the heat resistance is reduced at 40% by weight,
Glass fiber is excessively melted, and a large amount of gas is generated.
If the content exceeds 70% by weight, the elasticity of the glass fiber is reduced and the bending strength is significantly reduced. If the glass fiber is broken, the ceramic base material at the time of welding is not protected from the molten metal. This is because the fluidity of the slag decreases and a large amount of defects such as undercut and overlap occur.

Next, the content of Al ₂ O ₃ contained in the glass fiber body according to the present invention is 5 to 20% by weight. The reason specified in this range is that if the content is less than 5% by weight, the heat resistance is too low, a large amount of molten metal is generated and slag is generated, which makes gas release difficult, resulting in reduced slag separation and defects such as flow holes. %, The fire resistance of the glass fiber body is too high, which causes a decrease in the fluidity of the slag, and causes welding defects such as undercut.

The content of B ₂ O ₃ contained in the glass fiber according to the present invention is _{3 to} 15% by weight. The reason defined in this range is that B ₂ O ₃ has a function of expanding the plastic range of the glass fiber by performing a flux action in the glass fiber, but if it is less than 3% by weight, the fluidity of the slag is reduced and the slag is separated. Insufficiency and the resulting inner bead winding phenomenon occurs. On the other hand, if it exceeds 15% by weight, the bending strength of the glass fiber decreases, the glass fiber is crushed, and the back bead shape is wider and deeper than necessary. This is because the wires are formed and a large amount of wire is consumed, resulting in an increase in cost.

Next, the content of CaO contained in the glass fiber body according to the present invention is 8 to 28% by weight. Functionally, CaO is a component similar to B ₂ O ₃ and regulates the heat resistance, mechanical strength, plastic range, etc. of the glass fiber body. Here, the reason why the content is specified in this range is that if the content is less than 8% by weight, the fluidity of the slag is reduced, the peelability of the slag is lacking, and the undercut is generated due to the inner bead winding phenomenon. On the other hand, when the content exceeds 28% by weight, the refractory becomes low and the melt becomes excessively large, the slag is excessively generated and a large amount of gas is generated when the content exceeds 28% by weight. This is because air bubbles are generated in the bead, resulting in fatal welding defects.

Further, the glass fiber according to the present invention comprises Na
_It may contain an alkali metal oxide of ₂ O, K ₂ O, or Li ₂ O, and its content is preferably 0.5 to 4% by weight. Alkali metal oxides are important components for mechanical properties such as tensile strength, compressive strength, bending strength and the like of glass fibers and moldability.

Next, the water content of the glass fiber according to the present invention is 0.01 to 0.5% by weight. The reason specified in this range is that the water content affects welding defects as in the case of the ceramic base material, but if it exceeds 0.5% by weight, a large amount of water permeates into the back bead during welding, Later, a large amount of fine pores are generated in the bead.
The moisture is present on the surface of the glass fiber body and in the pores (including between fiber tissues) by absorbing moisture in the atmosphere.

The thickness of the glass fiber according to the present invention is preferably 0.3 to 1.5 mm. The glass fiber body facilitates the release of gas generated by the arc heat and prevents welding defects. At this time, the effect differs depending on the thickness of the glass fiber. If the thickness is less than 0.3 mm, the buffering effect between the steel and the ceramic base material cannot be obtained, and it will melt at an early stage during welding, making it difficult to expose the ceramic base material and release gas, and to dent in the back bead. While exposing and lowering the slag peeling, if it exceeds 1.5 mm, outgassing becomes easy, but because it is too thick, the glass fiber remains on the ceramic base material after welding, and the width of the back bead and It becomes difficult to adjust the depth and the like.

The glass fiber body may be a single or multiple glass fiber.

Next, a method of manufacturing a ceramic base material according to the present invention will be described. First, the raw materials used are, for example, 60 to
Α-quartz, tridymite or cristobalite having a particle size distribution of 80 mesh is used. In addition, these natural minerals include SiO ₂ , Al ₂ O ₃ , MgO, Na ₂ O, Fe
Some of them contain ₂ O ₃ , TiO ₂ , Li ₂ O, ZrO _2, etc. In this case, it is preferable to use these materials because the types of raw materials to be prepared are reduced.

Also, a plurality of raw materials corresponding to each component may be used. For example, as a SiO ₂ source, silica, kaolin, feldspar, mica, talc, mullite, etc., as an Al ₂ O ₃ source, alumina, kaolin, mullite, bauxite, etc.
Cordierite, magnesium oxide,
Examples of Na ₂ O sources such as talc include soda feldspar, sodium oxide, and water glass, and examples of K ₂ O sources include potassium feldspar, calcium titanate, and potassium glass. As for other components, Li oxide, iron oxide, barium titanate, titanium, rutile, zircon silicate, zirconia, or the like may be used.

From such raw materials, a ceramic base material is manufactured by a known manufacturing method. For example, if silica is 60-8
The mixture is pulverized to 0 mesh, soda feldspar, potassium feldspar, and alumina are mixed at a predetermined ratio, pulverized to 325 mesh or less, and both are mixed.

Thereafter, for example, additives such as polyvinyl alcohol (PVA205), stearic acid, paraffin wax, naphthalene, and sawdust are added to the raw material powder, and the mixture is dried in an oven at 90 to 110 ° C. for 8 to 24 hours. The molding pressure per piece is 10
After compression molding in a predetermined form at 30 kgf / cm ² , it was dried again in an oven at 90 to 110 ° C. for 24 hours.
Plasticize at 80-1,350 ° C for 6-14 hours. The amount of water can be adjusted to a desired range by adjusting the porosity.
The moisture content is measured according to the KSL5502 test method, and is measured after heating at 110 ° C. in a dryer for 2 hours [moisture content = (initial weight−dry weight) / dry weight × 10
0%]. Then package.

Next, a method for producing a glass fiber body according to the present invention will be described. _{SiO 2: 40~70%, Al 2} O 3:
_{5~20%, B 2 O 3:} 3~15%, CaO: 8~28
% In Na ₂ O, K ₂ O, another alkali metal oxide of one or more of the glass fiber sheets knitting or weaving while containing 0.5 to 4% by weight% singlet 10 as Li ₂ O, etc. 0.3 to 1.5 mm thick with a water content of 0.01
Manufacture glass fiber laminates with ~ 0.5%. In addition,
The amount of water can be adjusted to a desired range by adjusting the porosity.

Here, the above SiO ₂ , Al ₂ O ₃ , B ₂
O ₃ , CaO and Na ₂ O, K ₂ O, Li ₂ O are mixed and used in place of one or more pure glass fibers in place of minerals containing each of the above components, The glass of the present invention can be manufactured.

As raw materials, for example, SiO ₂ , Al ₂ O
Examples of the _three sources include those described above for the ceramic base material, and examples of the B ₂ O ₃ source include borax and boric acid.
Sources include limestone, dolomite, slaked lime, fluorite, silica lime and the like.

Using such a raw material, a glass fiber body is manufactured by a known manufacturing method. The above-described ceramic base material (1) manufactured as described above is adhered to a normal aluminum tape (2), and the glass fiber laminate (3) is adhered to the upper surface of the ceramic base material (1). And has the automatic welding support of the present invention.

According to the above, the glass fiber body manufactured according to the above is adhered to the upper surface of the manufactured ceramic base material, and further, the aluminum tape is closely adhered to the ceramic base material. Thus, the support for automatic welding of the present invention as shown in FIG. 1 is obtained.

In the support for automatic welding according to the present invention, the ceramic base material serves to protect the molten metal and form a back bead having a fixed width and depth, and the glass fiber is made of a steel material made of a ceramic base material. Acts as a cushioning material for perfect adhesion, easily releases gas generated at the time of welding, prevents welding defects such as undercut, sputtering, overlap, etc., and helps to have a good back bead and shape Play a role.

[0035]

EXAMPLES As shown in Tables 1 and 3, various tests were conducted by changing the composition of the ceramic base material and the glass fiber body of the support for automatic welding according to the present invention. As shown in FIG. 1, an aluminum tape (2) serving to attach a support to ordinary steel and having a large number of take holes for releasing gas generated during welding is attached to the lower surface of the ceramic base material (1). A glass fiber body (3) was attached to the upper surface of the ceramic base material (1), and various tests were conducted under the following welding conditions. The results are shown in Tables 2 and 4.

[0036]

[Table 1]

[0037]

[Table 2]

[0038]

[Table 3]

[0039]

[Table 4]

Welding conditions: (1) Welding wire and flux L-8 * S-707 US-40 * MF-100N YB * YB-150 (2) Welding voltage (V): 33 (3) Welding current (A): 900 (4) Steel thickness: 16 mm (5) Steel wire protrusion length: 15 mm (6) Proper gap: 2-3 mm (7) Welding posture: Downward posture

According to the test results shown in Table 2, in Examples 4 to 9 in which the ceramic base material falls within the scope of the present invention, the weld bead has a weld bead appearance, slag releasability, and no weld defect at all. It has been found.

On the other hand, Examples 1 to 3 which are outside the scope of the present invention
And Example 10 has many defects. Examples 1-3
With respect to the amount of Al ₂ O ₃ and MgO,
Since the amount of iO ₂ was small, the fire resistance of the ceramic base material was increased more than necessary, and the viscosity of the molten metal was reduced. Therefore,
After welding, defects in welding such as slag winding phenomenon and bead appearance hollow shape were caused, and the ceramic base material was easily damaged after welding because the porosity was low and the thermal shock resistance of the ceramic base material was reduced. In Example 10, although the weld bead shape and appearance were relatively good, the mechanical strength of the ceramic base material was significantly reduced due to the excessive amount of SiO ₂ added, and a portion of the ceramic base material was thermally degraded. It was easily damaged by impact and external pressure, and dust was generated after welding. In addition, the water content was too high, and water was present as fine pores in the bead during welding, causing welding defects.

Further, according to the test results in Table 4, it was found that in Examples 14 to 18 in which the glass fiber body falls within the scope of the present invention, the glass fiber body had a good welding bead as a support for automatic welding. On the other hand, in Examples 11 to 13 and Examples 19 to 22, which are outside the scope of the present invention, many welding defects occurred. Example 1
For, SiO ₂ amount is less 1~13, Al ₂ O ₃
Also, since the amount of B ₂ O ₃ was large, the bending strength, which was the mechanical strength of the glass fiber body, was reduced, and remarkable high heat resistance was exhibited.
Therefore, the glass fiber is crushed, the back bead shape is formed wider and deeper than necessary, and welding defects such as slag winding phenomenon and overlap due to lowering of slag viscosity due to improvement in heat resistance of the glass fiber body are caused. occured. In Example 19, the amount of SiO ₂ was large, and Al ₂ O ₃ and B ₂ O ₃
Since the amount was small, the heat resistance of the glass fiber body was reduced, and therefore, slag was excessively generated, gas was difficult to be released, and welding defects such as flow holes, sputtering, and reduced peeling of the slag occurred. Further, in Example 20, the thickness of the glass fiber body was too thin to make it difficult to release gas generated at the time of welding, leading to welding defects such as depressions and reduced slag peelability. In Examples 21 and 22, the glass fiber thickness was reduced. It is difficult to adjust the width and depth of the back bead because it is too thick, and the glass fiber body remains on the ceramic base material during welding, causing overlap, slag winding, flow holes, etc. Such as welding defects.

[Brief description of the drawings]

FIG. 1 is a support for automatic welding according to the present invention.

FIG. 2 is a conventional support for automatic welding.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ceramic base material 2 Aluminum tape 2a Magnetic clamp 3 Glass fiber body 4 Steel material

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁶ , DB name) B23K 37/06 C04B 35/00

Claims (2)

(57) [Claims] 1. A composition comprising 70 to 95% by weight of SiO ₂ , 2 to 15% by weight.
Wt% of Al ₂ 0 _3, 1~5 wt% of MgO, 1 .2 to
8% by weight of Na ₂ O and / or K ₂ O and 0.01
Ceramic matrix having a porosity of 25 to 48% and a fire resistance of 1,435 to 1,670 ° C., containing water of 0.5 to 0.5% by weight, and 40 to 70% by weight of SiO laminated on the matrix.
_2, 5 to 20 wt% of Al ₂ O _3, 3 to 15 wt% of B ₂
O _3, 8 to 28 wt% of CaO, including 0.5-4% by weight of alkali metal oxide and 0.01 to 0.5% by weight of water, glass fibers having a thickness of 0.3~1.5mm A support for automatic welding comprising a body. 2. The automatic welding support according to claim 1, wherein the base material contains quartz, tridymite and / or cristobalite.