【考案の詳細な説明】[Detailed explanation of the idea]
〔産業上の利用分野〕
本考案は、溶接母材の開先裏面側に当接して溶
融金属が抜け落ちるのを防止し且つ溶接裏面側の
ビート外面を整えるという作用を発揮する片面溶
接用裏当材に関し、詳細には複数個の固形耐火物
を長手方向に接続して構成される連結型裏当材に
改良を加え、屈曲した溶接線に対して使用すると
きであつても母材への密着性が良く、しかも座屈
に対して抗力のある溶接用裏当材を提供しようと
するものである。
〔従来の技術〕
複数個の固形耐火物を連接してなる連結型裏当
材は公知であり、その構成単位であるユニツトブ
ロツクを、第２図ａ，ｂ，ｃに例示する。まず第
２図ａに示す固形耐火物２は溶接母材への当接面
６に対して垂直な接合面５を有し、溶接母材当接
面６の中央部には、溶接線長手方向に沿つて凹型
のスラグポケツト４を形成する。一方第２図ｂに
示す固形耐火物２は、隣接する固形耐火物同士の
接合面５ａ，５ｂには対応した凸状及び凹状丸み
を有する曲面が形成され、ナツクル状継手を構成
している。また第２図ｃに示す固形耐火物２に
は、接合面側に嵌合突部８ａ，８ｃが形成される
と共に、該嵌合突部８ａ，８ｃを嵌装する凹部８
ｂ，８ｄが形成され、隣接する固形耐火物２同士
が互いに屈曲できる様に嵌合突部８ａ，８ｃ及び
凹部８ｂ，８ｄの一部には湾曲面が形成され、第
２図ｂの例と同様ナツクル状継手を構成してい
る。なおこれら第２図ｂ，ｃに示された裏当材は
特開昭54−149343号に開示されている。
この様な固形耐火物２を連接して構成される連
結型裏当材は第３図（断面図）に示す様に、溶接
母材１の開先裏面に溶接線長手方向に沿つて固形
耐火物２を連続させる様に当接して使用され、固
形耐火物２を包む様に接着テープ３で囲撓し、該
接着テープ端部を溶接母材１の裏面に貼付して裏
当材の落下を防止する。
固形耐火物２は珪石、長石、ジルコン、アルミ
ナ等のセラミツク原料を配合し、プレス成形、乾
燥、焼成等の工程を経て製造される。良好な溶接
作業性及び裏ビード形状を得るための好ましい化
学成分としては、SiO2：45〜80％、Al2O3：15〜
35％、MgO：０〜20％、ZrO2：０〜10％、
NaO，K2O，Li2Oの１種以上：0.3〜５％を一例
として挙げることができる。また接着テープ３の
テープ材料としては薄くて耐熱性の高い金属、例
えばアルミニウム、鉄、銅の箔やガラス繊維等が
適しており、接着剤には高強度のアクリル樹脂や
エラストマー等が汎用される。
〔考案が解決しようとする問題点〕
固形耐火物２同士が連接される接合面５ａ，５
ｂ、及び嵌合突部８ａ，８ｃと凹部８ｂ，８ｄの
一部が第２図ｂ，ｃに示す様に、湾曲面同士を回
転自在となる様に嵌合する構造である場合、当接
面における可撓性が優れているため溶接線の屈曲
に対する追従性は良好であり、かつ連接する固形
耐火物２間の隙間が狭いので溶融金属の抜け落ち
が少なく裏ビード形状も良好となる。しかしなが
ら上記可撓性が良好であり過ぎるため、狭隘部の
如く裏当材取付作業性が悪い部分では接着テープ
の貼付面が十分に確保できないこともあり、固形
耐火物２の自重によつて溶接母材１裏面と固形耐
火物２の間に隙間を生じ、溶接金属のはみ出しを
招くという欠点に遭遇している。また上記の様に
固形耐火物２の端部に湾曲面を形成するには、繁
雑な加工作業が必要となり、該固形耐火物２の製
造コストは高くついてしまい、実用上不向きであ
る。
一方第２図ａに示す様な固形耐火物２を連接さ
せた裏当材を使用する場合は、当接面における可
撓性が劣るため屈曲した溶接線に対する追従性が
悪く、しかもこれを無理やり追従させようとすれ
ば互いに隣接する固形耐火物の端面同士の間が母
材裏面側で離反することになり、屈曲角が大きく
なればなるほど隙間が大きくなつていき溶融金属
が抜け落ち易く、且つ裏ビード形状が悪化してし
まうという欠点がある。
そこで本考案者らは、屈曲した溶接線に対して
妥当な範囲の可撓性をもつて適合し、溶接母材裏
面に確実に密着し、しかも溶融金属の抜け落ちの
少ない裏当材の研究を行ない、本考案を完成させ
るに至つた。
〔問題点を解決するための手段〕
溶接線長手方向に隣接される固形耐火物の各接
合面が、２以上の折返し辺を有する厚さ方向への
ジグザグ状傾斜平面によつて形成される様な固形
耐火物を採用してこれを連設してなる点に本考案
の要旨が存在する。
〔作用〕
溶融金属が裏当材から抜け落ちない様にするた
めには、隣接する固形耐火物が互いに接合する面
を密着させて隙間が生じない様に構成しなければ
ならず、しかもこの関係が屈曲状態においても維
持されなければならない。ところで溶接母材が屈
曲され、溶接線もそれに合わせて屈曲する場合、
裏当材は各固形耐火物の接合面で屈折させなけれ
ばならないが、各接合面における座屈性（裏当材
全体としてみれば可撓性）が高くなると、固形耐
火物同士の相互保持性が低くなつてしまう。そこ
で該接合面として２以上の折返し辺を有する厚さ
方向へのジグザグ状傾斜平面を採用して固形耐火
物を形成すれば、固形耐火物同士を接合面から屈
折させた場合、２つの折返し辺のうち少なくとも
１つ辺が、隣接するもう１つの固形耐火物の接合
面のいずれか１つの傾斜面に引掛かつて座屈を阻
げる方向に作用し、その結果として固形耐火物同
士の保持性が高められる。
また隣接する固形耐火物同士は、少なくとも１
つの折返し辺（平面の交線）と隣接する固形耐火
物の接合面のいずれか１つの傾斜面と接触して空
隙の形成を防止するので、固形耐火物同士の隙間
からの溶融金属の抜け落ちを最小限に抑えること
ができる。
〔実施例〕
第１図ａは本考案の代表的な実施例を示す固形
耐火物の側面図、第１図ｂは第１図ａのＢ−Ｂ線
断面図を示す。該側面図からも明らかな様に、隣
接する固形耐火物２同士の接合面５には、面と面
との交点（紙面の厚さ方向に見れば交線）である
Ｅ，Ｆ，Ｇ，Ｈ（以下これらを辺と言う）が形成
され、２つの折返し辺Ｆ，Ｇを有すると共に、ジ
グザグ状に連なる平面Ｅ−Ｆ，Ｆ−Ｇ，Ｇ−Ｈ
（図面上は夫々線となつて現われるが、紙面貫通
方向に続いているので実際上は面である）によつ
て対向面が形成される。
溶接母材当接面６の反対側には接着テープ３が
接着され、溶接線長手方向に沿つて固形耐火物２
を連ねる。前記固形耐火物２の１つを取り出して
拡大した側面図を第４図に示す。溶接母材当接面
６に対する各傾斜平面Ｅ−Ｆ，Ｆ−Ｇ，Ｇ−Ｈの
傾きを夫々An１，An２，An３としたとき、実
際上の加工製造条件を考慮すれば以下の範囲で限
定される。
即ち 10゜An１＜90゜
0゜＜An２＜90゜
10゜An３＜90゜
の範囲内であることが推奨されるが、溶融金属の
抜け落ちを少なくするためには、溶融金属の落下
を食い止める必要があるのでAn２は小さい程好
ましい。
一方湾曲した溶接線に沿つて裏当材を当接した
場合、各固形耐火物２は第５図ａ，ｂに示す様な
状態で屈曲していく。湾曲溶接線が凹型状を示す
ときは、第５図ａに示す様に固形耐火物２同士は
辺Ｅ，E′を中心に回転屈折する。辺Ｅから固形耐
火物２の厚さ方向（図では下方向）へ離れるにし
たがつて、固形耐火物同士の隙間は徐々に広がつ
てゆくが、辺Ｆが隣接する固形耐火物２のF′−
G′面とせり合い、屈折を阻止する方向に働く。
また反対に第５図ｂに示す如く溶接線が凸型状を
示すときは、固形耐火物２は辺Ｈ，H′を中心に
回転屈折する。このときには辺G′がＧ−Ｆ面と
せり合う様に移動し、屈折を阻止する方向に作用
する。従つて固形耐火物２を連接させて下部を接
着テープ３によつて保着し、固形耐火物２の１つ
を１点のみで保持しようとすれば、第６図ｂに示
す如く各隣接する固形耐火物２同士は接合面５の
耐座屈作用によつて、わずかな屈曲を示す程度に
抑えられる。一方固形耐火物２同士の接合面が第
２図ｂ，ｃに示した様なナツクル状継手で構成さ
れる場合には、隣接する固形耐火物２同士の間に
耐座屈作用が働かないので、第６図ａの様に、各
固形耐火物２は接合面５より大きく曲がりうなだ
れてしまつた様な外観を呈する。第６図ｂに示し
たような耐座屈作用を高めるためには、第４図に
示した角度An１及びAn３を小さくすればする程
良いことが分かる。
〔実験例〕
第７図ａに示す様な湾曲溶接母材１を対象とし
て下向片面溶接を行なう。裏当材としては、第７
図ｂに示す寸法形状のものを使用し、その側面は
第８図ａ，ｂに示す。尚第７図ｃは第７図ａのＣ
−Ｃ線断面図である。固形耐火物２は10個を長手
方向に連接させて250mmの裏当材を構成した。片
面溶接を行なつた後の各溶接ビードの品質は第１
表に示す通りであつた。
[Industrial Application Field] The present invention provides a backing for single-sided welding that comes into contact with the back side of the groove of the weld base material to prevent molten metal from falling out and to prepare the outer surface of the bead on the back side of the weld. Regarding materials, we have improved the connected backing material, which is made up of multiple solid refractories connected in the longitudinal direction, so that it does not touch the base material even when used on bent weld lines. The object of the present invention is to provide a backing material for welding that has good adhesion and resistance to buckling. [Prior Art] A connected backing material formed by connecting a plurality of solid refractories is well known, and unit blocks that are its constituent units are illustrated in FIGS. 2a, b, and c. First, the solid refractory 2 shown in FIG. A concave slug pocket 4 is formed along. On the other hand, in the solid refractory 2 shown in FIG. 2b, curved surfaces having corresponding convex and concave roundness are formed on the joining surfaces 5a and 5b of adjacent solid refractories, forming a knuckle-shaped joint. Further, the solid refractory 2 shown in FIG. 2c has fitting protrusions 8a, 8c formed on the joint surface side, and a recess 8 into which the fitting protrusions 8a, 8c are fitted.
b, 8d are formed, and curved surfaces are formed in some of the fitting protrusions 8a, 8c and the recesses 8b, 8d so that adjacent solid refractories 2 can be bent to each other. Similarly, it constitutes a knuckle-shaped joint. The backing materials shown in FIGS. 2b and 2c are disclosed in Japanese Patent Application Laid-Open No. 149343/1983. As shown in Fig. 3 (cross-sectional view), the connected type backing material constructed by connecting such solid refractories 2 has a solid refractory material attached to the back surface of the groove of the welding base material 1 along the longitudinal direction of the weld line. The solid refractory material 2 is surrounded by an adhesive tape 3, and the end of the adhesive tape is attached to the back side of the welding base material 1 to prevent the backing material from falling. prevent. The solid refractory 2 is manufactured by blending ceramic raw materials such as silica, feldspar, zircon, and alumina, and through processes such as press molding, drying, and firing. Preferred chemical components for obtaining good welding workability and back bead shape include SiO2 : 45-80%, Al2O3 : 15-80 %.
35%, MgO: 0-20%, ZrO2 : 0-10%,
One or more of NaO, K 2 O, and Li 2 O: 0.3 to 5% can be cited as an example. In addition, thin and highly heat-resistant metals such as aluminum, iron, copper foil, glass fiber, etc. are suitable as tape materials for the adhesive tape 3, and high-strength acrylic resins, elastomers, etc. are commonly used as adhesives. . [Problem to be solved by the invention] Joint surfaces 5a, 5 where the solid refractories 2 are connected to each other
b, and a part of the fitting protrusions 8a, 8c and recesses 8b, 8d, as shown in FIGS. Since the surface has excellent flexibility, the bending of the weld line can be easily followed, and since the gap between the connected solid refractories 2 is narrow, there is less molten metal falling out, and the back bead shape is also good. However, because the above flexibility is too good, it may not be possible to secure a sufficient surface for attaching the adhesive tape in areas where the workability of attaching the backing material is poor, such as in narrow areas, and the solid refractory material 2 may be welded due to its own weight. A drawback has been encountered in that a gap is created between the back surface of the base material 1 and the solid refractory 2, causing weld metal to protrude. Further, in order to form a curved surface at the end of the solid refractory 2 as described above, complicated machining operations are required, and the manufacturing cost of the solid refractory 2 is high, making it unsuitable for practical use. On the other hand, when using a backing material in which solid refractories 2 are connected as shown in Fig. 2a, the flexibility of the contact surface is poor, so the ability to follow a bent weld line is poor, and it is difficult to If you try to make them follow each other, the end faces of adjacent solid refractories will separate from each other on the back side of the base metal, and the larger the bending angle, the larger the gap, making it easier for molten metal to fall out, and There is a drawback that the bead shape deteriorates. Therefore, the inventors of the present invention conducted research on a backing material that would fit the curved weld line with a reasonable range of flexibility, would reliably adhere to the back surface of the weld base material, and would prevent molten metal from falling out. This led to the completion of this invention. [Means for solving the problem] Each joint surface of the solid refractories adjacent to each other in the longitudinal direction of the weld line is formed by a zigzag inclined plane in the thickness direction having two or more folded sides. The gist of the present invention lies in the fact that solid refractories are used and these are connected in series. [Function] In order to prevent molten metal from falling out of the backing material, adjacent solid refractories must be configured so that their joining surfaces are in close contact with each other and there are no gaps, and this relationship must be maintained. It must also be maintained in the flexed state. By the way, when the weld base metal is bent and the weld line is also bent accordingly,
The backing material must be bent at the joint surfaces of each solid refractory, but as the buckling property (flexibility of the backing material as a whole) at each joint surface increases, the mutual retention of the solid refractories increases. becomes low. Therefore, if a solid refractory is formed by adopting a zigzag inclined plane in the thickness direction having two or more folded sides as the joint surface, when the solid refractories are bent from the joint surface, two folded sides At least one side of the solid refractories acts in a direction that prevents buckling by hooking onto one of the inclined surfaces of the joint surfaces of another adjacent solid refractory, and as a result, the retention of the solid refractories is improved. is enhanced. In addition, adjacent solid refractories have at least 1
This prevents the formation of voids by contacting one of the inclined surfaces of the two folded sides (intersection line of planes) and the joint surface of the adjacent solid refractories, thereby preventing molten metal from falling out from the gaps between the solid refractories. can be minimized. [Embodiment] FIG. 1a is a side view of a solid refractory showing a typical embodiment of the present invention, and FIG. 1b is a sectional view taken along the line B--B in FIG. 1a. As is clear from the side view, the joint surfaces 5 of the adjacent solid refractories 2 have intersections of surfaces E, F, G, H (hereinafter referred to as sides) is formed, has two folded sides F and G, and has planes E-F, F-G, and G-H that are connected in a zigzag shape.
(Although each appears as a line in the drawing, since it continues in the direction penetrating the page, it is actually a plane) to form the opposing surface. Adhesive tape 3 is adhered to the opposite side of the weld base metal contact surface 6, and solid refractory 2 is attached along the longitudinal direction of the weld line.
A series of An enlarged side view of one of the solid refractories 2 is shown in FIG. When the inclinations of each inclined plane E-F, F-G, and G-H with respect to the welding base metal contact surface 6 are An1, An2, and An3, respectively, it is limited to the following range in consideration of actual processing and manufacturing conditions. be done. In other words, it is recommended that the range be 10゜An1＜90゜ 0゜＜An2＜90゜ 10゜An3＜90゜, but in order to reduce the falling of molten metal, it is necessary to prevent the molten metal from falling. Therefore, the smaller An2 is, the better. On the other hand, when a backing material is abutted along a curved weld line, each solid refractory 2 is bent as shown in FIGS. 5a and 5b. When the curved weld line has a concave shape, the solid refractories 2 are rotated and bent around sides E and E' as shown in FIG. 5a. The gap between solid refractories gradually widens as the distance from side E increases in the thickness direction (downward in the figure) of solid refractory 2, but side F of adjacent solid refractory 2 ′−
It comes into contact with the G′ plane and works in the direction of blocking refraction.
On the other hand, when the weld line has a convex shape as shown in FIG. 5b, the solid refractory 2 rotates and bends around the sides H and H'. At this time, the side G' moves so as to come into contact with the GF plane, acting in a direction to prevent refraction. Therefore, if you try to connect the solid refractories 2 and secure the lower part with the adhesive tape 3, and hold one of the solid refractories 2 at only one point, each adjacent The solid refractories 2 are suppressed to exhibit slight bending due to the anti-buckling effect of the joint surfaces 5. On the other hand, if the joint surfaces of the solid refractories 2 are constituted by a knuckle-shaped joint as shown in Fig. 2b and c, there is no buckling resistance between the adjacent solid refractories 2. As shown in FIG. 6a, each solid refractory 2 has an appearance that is bent to a greater extent than the joint surface 5 and hangs down. It can be seen that in order to enhance the buckling resistance as shown in FIG. 6b, the smaller the angles An1 and An3 shown in FIG. 4, the better. [Experimental Example] Downward single-sided welding was performed on a curved welding base material 1 as shown in FIG. 7a. As the backing material, No. 7
A device having the dimensions and shape shown in FIG. 8 is used, and its side surfaces are shown in FIGS. 8a and 8b. Note that Figure 7c is C in Figure 7a.
-C line sectional view. Ten solid refractories 2 were connected in the longitudinal direction to form a 250 mm backing material. The quality of each weld bead after single-sided welding is
It was as shown in the table.
〔考案の効果〕[Effect of idea]
本考案の固形耐火物を使つた裏当材を、屈曲し
た溶接線をもつ母材の片面溶接に使用することに
より、溶融金属の抜け落ちが少なくなり、しかも
裏ビード形状の良好な溶接部が得られた。また各
固形耐火物間の耐座屈性が高く、自重により溶接
母材から離反してしまうことも防止できる。
By using the solid refractory backing material of the present invention for single-sided welding of base metals with curved weld lines, drop-off of molten metal is reduced and a welded part with a good back bead shape can be obtained. It was done. In addition, the buckling resistance between the solid refractories is high, and it is possible to prevent them from separating from the welding base material due to their own weight.
【図面の簡単な説明】[Brief explanation of drawings]
第１図ａは本考案の代表的な裏当材を示す側面
図、第１図ｂは第１図ａのＢ−Ｂ線断面図、第２
図ａ〜ｃは従来の固形耐火物を示す斜視図、第３
図は裏当材の使用形態を示す断面図、第４図は第
１図ａで示した固形耐火物の側面拡大図、第５図
ａ，ｂは本考案品の使用状態を示す側面図、第６
図ａ，ｂは裏当材の耐座屈性を示す説明図、第７
図ａ，ｂ，ｃは実験条件を示す説明図であり、第
８図ａ，ｂは実験に用いられた固形耐火物の寸
法、形状を示す側面図である。
１……溶接母材、２……固形耐火物、３……接
着テープ、４……スラグポケツト、５……接合
面、５ａ，５ｂ……曲面状接合面、６……溶接母
材当接面、７……離型紙。
Fig. 1a is a side view showing a typical backing material of the present invention, Fig. 1b is a sectional view taken along the line B-B of Fig. 1a, and Fig. 2
Figures a to c are perspective views showing conventional solid refractories;
The figure is a sectional view showing how the backing material is used, FIG. 4 is an enlarged side view of the solid refractory shown in FIG. 1 a, and FIGS. 5 a and b are side views showing how the product of the present invention is used. 6th
Figures a and b are explanatory diagrams showing the buckling resistance of the backing material.
Figures a, b, and c are explanatory diagrams showing the experimental conditions, and Figures 8a and b are side views showing the dimensions and shape of the solid refractory used in the experiment. 1... Welding base metal, 2... Solid refractory, 3... Adhesive tape, 4... Slag pocket, 5... Joint surface, 5a, 5b... Curved joint surface, 6... Welding base metal contact Surface, 7...Release paper.