JPH0671680B2 - Welding method using backing member of reinforcing bar joint - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION << Industrial Application Field >> The present invention, when welding a reinforcing bar and a reinforcing bar, after fitting a backing member to a joint part to be joined of the reinforcing bars, Welding is performed from the notch opening of the backing member, and at this time, the molten metal of the above-mentioned reinforcing bar does not flow unintentionally, and further, it does not melt down, so that desirable joint welding can be done. The present invention relates to a welding method using the backing member of the rebar joint portion.

<< Prior Art >> As is known, there are methods such as gas pressure welding, welding joints and mechanical joints as means for joining reinforcing bars.

As for the above-mentioned welded joint construction method, whether by manual welding or semi-automatic welding, as shown in FIG. 4, the outer periphery of the joints a ′, a ′, which are the end portions of the reinforcing bars a, a, are made of steel or copper material and are short. Split groove b
Is surrounded by a backing member c having a vertical pipe shape, and the joint groove portions d, d of the reinforcing bars a, a are separated by a predetermined distance e.
With a distance of (root interval), it is welded and fixed to the backing member c by the temporary fixing points f, f, and the welding rod h is inserted from the notch opening g opened in the backing member c. The two reinforcing bars a and a are welded together.

As a result, the molten metal of the reinforcing bars a, a is completed welding without flowing down as described above, but in the case of the backing member c made of steel, after the joint welding of the reinforcing bars a, a is completed, Since the reinforcing bar and the backing member are welded to each other by welding, it becomes difficult to remove the reinforcing bar and the backing member, so that it becomes impossible to perform visual inspection of the joint portion.

On the other hand, if a copper material is used for the backing member, it is possible to remove the copper material, which is a copper plate, after completion of welding, so that the appearance of the joint part can be inspected, but the backing member is severely damaged, so it is expensive. There is a practical problem that copper consumption is large.

In addition, the fact that the backing member cannot be removed as described above means that only the joint portion has a large diameter, the distance between the reinforcing bars is not uniform, and uniform bar arrangement cannot be obtained. Even during the filling work, it is difficult to guarantee the complete filling.

Therefore, the backing member has already been destroyed by breaking the preconceived idea that the backing member was made of metal, and after the completion of the welded joint, the backing member was crushed, and ceramics was selected as the material so that it could be removed. To ensure that visual inspection can be performed by visually observing the joint joint directly.
As a result, it can be provided at a lower cost than steel, copper, and the like, and eliminates the large-diameter portion remaining due to the backing member of the joint joint, and enables rebar with uniform intervals between the rebars. Therefore, the ones shown in FIGS. 5 and 6 have been proposed.

That is, in the backing member i of FIG. 5, a main body j made of ceramics is bent into a horseshoe-shaped cross section, and a narrow opening 1 is opened between the free edges k, k of the reinforcing bar a. The joint groove portions d, d of a, a are fitted.

However, since the narrow opening 1 is provided as described above, the backing member i must be fitted to the reinforcing bar a in advance before the reinforcing bars a and a are assembled. Therefore, the assembling of the reinforcing bars a and a is performed. At this time, the backing member i may be damaged.

Therefore, in order to further solve the above-mentioned problems, a backing member m as shown in FIG. 6 has also been proposed. In this case, the opening n between the free edges k ′, k ′ of the reinforcing bar a, a
The diameter is larger than the diameter of the reinforcing bars a and a, so that even after the reinforcing bars a and a are assembled, the reinforcing bars a and a can be fitted to required positions from the outside, and the reinforcing bars a and a can be bound to the reinforcing bars a and a by unillustrated fastening lines.

However, even if the reinforcing bar joint is welded using any of the backing members shown in FIG. 5 and FIG.
There is no problem if the gaps q, q'between the inner peripheral curved surfaces p, p'of i, m and the reinforcing bar a are relatively narrow, but if it is a large-diameter reinforcing bar, the ribs protruding from the outer peripheral surface are also large as such. Therefore, the above gaps q and q'will never become large.As a result, the weld metal melted by welding is flowed down from the backing member through this gap and droops down. As a result, the welding strength of the joint portion is not sufficient, and there is a risk that the molten metal will fall.

<< Problems to be Solved by the Invention >> Claim (1) has been studied in view of various problems in the above-mentioned welded joint construction method, and breaks down the conventional idea that the backing member has been formed of metal, After completion of the welded joint, just crush the backing member and select ceramics as the material so that it can be removed, so that the joint joint can be directly visually inspected to ensure visual inspection. Instead of filling the non-combustible material in the gap between the backing member and the reinforcing bar, and then performing welding, the molten metal in the reinforcing bar joint part may flow and drop. The aim is to ensure weld strength and completely prevent the danger of drooling of the molten metal. Moreover, at this time, as the above-mentioned non-combustible material, a material having a heat-melting property is selected so that the molten metal produced by the welding operation comes into contact with the non-combustible material and melts it. Improves peelability when peeling the backing member by crushing, removing the backing member,
Its purpose is to facilitate cleaning and to allow the surface shape of the weld metal formed by solidification of the molten metal to be smoothly finished.

In the welding method of claim (2), the point different from claim (1) is that in the case of a vertical bar, when the reinforcing bar has a large upper diameter and a small reinforcing bar has a lower diameter, By filling the non-combustible material with heat-melting property only in the gap formed between the lower-diameter reinforcing bars, the non-combustible material is provided in only one place, effectively increasing the welding strength and It seeks to prevent unintended flow, sag, improve strippability, and improve the surface finish of molten metal.

<< Means for Solving the Problem >> In order to achieve the above-mentioned object, the present invention provides a first rebar and a second rebar to be welded, each having a predetermined joint groove portion. In a state in which the backing bodies are opposed to each other with a separation distance therebetween, the inner peripheral curved surface of the ceramic notched cylindrical backing body is formed over the first and second joint ends of the first and second reinforcing bars. In the fitted state, a notched opening for welding work is opened between the opening edges of the backing body, and the inner peripheral curved surface of the backing body and one or both of the first and second reinforcing bars are formed. The gap formed between the outer peripheral surfaces is filled with a non-combustible material having heat melting property,
By inserting a welding tool from the notch opening and welding between the joint groove portions of the first and second reinforcing bars, the non-combustible material is melted by the molten metal generated by the welding operation. Then, the present invention intends to provide a welding method using a backing member of a reinforcing bar joint portion, characterized in that the ceramic backing body is crushed and removed. Is a vertical bar state in which the joint groove portions of the first reinforcing bar having a large upper diameter and the second reinforcing bar having a small lower diameter to be welded are continuously connected to each other with a predetermined separation distance. The first and second
A notch for welding work between the open end edges of the backing body with the inner peripheral curved surface of the ceramic notched cylindrical backing body being fitted over the first and second joint ends of the reinforcing bar. Along with the opening of the opening, the gap formed between the inner peripheral curved surface of the backing body and the outer peripheral surface of the second reinforcing bar is filled with a non-combustible material having heat melting property, and the notch opening is formed. Insert the welding tool from
By welding between the joint groove portions such as the second reinforcing bar, the non-combustible material is melted by the molten metal generated by the welding work, and then the backing body made of ceramics is crushed. The present invention is intended to provide a welding method using a backing member of a reinforcing bar joint portion, which is characterized in that the welding is performed by removing it.

<< Operation >> In the welding method according to claim (1), the backing body is fitted to the weld joints of the first and second reinforcing bars, and the welding operation is performed through the notch opening of the body. By doing so, in the first and second reinforcing bars, the joint groove portions are melted respectively, and this tries to flow in the molten metal state as a receiving of the backing body, but with the first and second reinforcing bars. Since the gap with the inner peripheral curved surface of the backing body is closed by the noncombustible material, the weld metal does not flow or drip out of the backing body through this gap, and a sufficient amount of the first , There will be a stagnation between the ends of the second joint,
When this is cooled and solidified, a satisfactory welding strength is obtained.

Moreover, since the above-mentioned non-combustible material has a heat-melting property, the molten metal produced by performing the welding operation as described above comes into contact with the non-combustible material and brings the surface side into a molten state, When the backing body is crushed and removed after the welding is completed, the non-combustible material and the backing body have good peelability, and the surface of the molten metal is also solidified by contact with the molten non-combustible material. Therefore, a smooth surface can be obtained.

Further, in the case of claim (3), the second lower diameter
The non-combustible material is filled only in the reinforcing bar side of the, but the molten metal accompanying the welding work flows downward because it is a vertical bar,
Therefore, the undesired flow displacement and sagging of the molten metal are sufficiently prevented, and the other actions are the same as in the case of the above claim (1).

<< Example >> When the welding method according to the present application is described in detail with reference to FIGS. 1 to 3, in the method, a backing member 1 as shown below is used.

This is a backing body made of ceramics
1a is formed into a notched cylindrical shape having a desired thickness and a cross section of a substantially horseshoe shape, and has a predetermined length L.

In other words, the backing body 1a has a cutout opening portion obtained by partially cutting a cylindrical pipe in the longitudinal direction.
1b has an open shape, and in the figure, 1c and 1d respectively represent an inner peripheral curved surface and an outer peripheral curved surface of the backing body 1a, and 1e and 1e.
Reference character e denotes an opening edge portion of the main body 1a.

For the illustrated backing body 1a, the cutout opening 1b,
If the diameters of the first and second rebars A and A'are made larger, the rebars A and A'will be installed even after the rebars A and A'are assembled.
A'can be fitted from the outside as described below,
When the notch opening 1b is smaller than the diameter of the first and second rebars A and A ', the rebar must be fitted in advance.

Further, the backing body 1a may not be integrally formed as in the above-mentioned embodiment, but may be a structure in which a pair of half-divided bodies are pivotally attached by a hinge. , It can be fitted even after the rebar is assembled, and the notch opening can be made sufficiently small when the half body is closed. As will be described later, molten metal generated during welding drips from the opening edge. It is also desirable to prevent this.

Using the backing member 1 as described above, a backing body
It is assumed that the inner peripheral curved surface 1c of 1a is fitted over the first and second joint end portions A ₁ , A ₁ ′ of the first and second reinforcing bars A, A ′. In order to hold the backing member 1 by using a binding line (not shown) as is known, the first and second reinforcing bars A,
It will be tied to A ', or other support tools will be used. At this time, of course, the first and second reinforcing bars A, A', the joint groove portions A ₂ , A ₂ 'have a predetermined separation distance. The backing body 1a is in a state of being continuously connected to the backing body 1a from the cutout opening portion 1b between the opening end edges 1e and 1e.
_2. Make welding work possible for A and ₂ '.

Now, when the backing body 1a is fitted on the first and second rebars A and A'as described above, in the case of FIG. 1 according to claim (2), the first rebar A Is formed in the upper large diameter,
The second reinforcing bar A ′ has a lower small diameter. Therefore, in the case of such a vertical reinforcing bar, there is no difference between the first and second reinforcing bars A and A ′ and the inner peripheral curved surface 1c of the backing body 1a. Although the gap G also occurs, the gap in the first rebar A is relatively small, whereas the gap in the second rebar A ′ is considerably large.

In such a case, in the welding method of claim (2),
The gap G on the second reinforcing bar A ′ side is filled with the noncombustible material 2.

Here, as the non-combustible material 2, a material having a heat melting property such as glass wool is selected.

In practice, in order to apply the non-combustible material 2, the non-combustible material 2 is wound around the joint end A ₁ ′ of the second reinforcing bar A ′ in advance, and the backing body 1 a is fitted from the outside thereof. It is better to let them do it.

On the other hand, in the case of FIG. 2 and FIG. 3 according to claim (1), the first and second reinforcing bars A and A ′ even if they are vertical bars.
The non-combustible material 2 is filled in one or both of the gaps G between the backing body 1a and the backing body 1a, but the one shown in FIG. 2 has the same first and second reinforcing bars A and A '. Even when the outer diameter is large, the distance between the joint groove portions A ₂ and A ₂ ′ is large (for example, 15 to 20 mm). In such a case, the volume of molten metal also increases, and that much Although the molten metal is apt to flow and drop, the filling of the non-combustible material 2 completely prevents this.

In addition, in FIG. 3, as described above, the first and second reinforcing bars are provided.
This shows the case where A and A ′ are thick and the gap G becomes large due to this (for example, 4 mm or more). Even in such a case, the noncombustible material arranged in the gap G is effective, and the molten metal at the time of welding Therefore, it is possible to prevent the flow and dripping.

Further, as in the case of the above-mentioned claim (2), in this case also, the non-combustible material 2 is made to have a heat melting property, so that the molten metal at the time of welding melts the surface of the non-combustible material 2. Therefore, after the molten metal solidifies, the peeling property between the backing body 1a and the incombustible material 2 becomes good, and the surface shape of the deposited metal becomes smooth.

<< Effects of the Invention >> Since the present invention is carried out as described above, in the case of claim (1), the non-combustible material filled in the gap causes undesired flow of the molten metal and sagging. Welding that blocks, and thus has sufficient strength, can be easily performed without the risk of sagging of the molten metal, and of course, because the non-combustible material has thermal melting properties,
The work of crushing and removing the backing member and the work of cleaning can be easily performed by improving the peelability, and the surface of the deposited metal can be finished smooth.

Further, in claim (2), it is a vertical bar, and only by filling the non-combustible material in the gap in the reinforcing bar of the lower small diameter,
The same effect as that of claim (1) can be obtained.

[Brief description of drawings]

1 (a) and 1 (b) are respectively a perspective view and a vertical sectional front view of a welding joint part showing a welding method according to claim (2), and FIG. 2 is a welding method showing a welding method according to claim (1). FIGS. 3 (a) and 3 (b) are cross-sectional plan views and longitudinal side views, respectively, of a welded joint part showing another embodiment of the above-mentioned claim (1). b) is a front explanatory view and right side end view, respectively, of the welded joint part showing a method of welding a reinforcing bar joint part by a conventional backing member, and FIGS. 5 (a) (b) (c) have already been proposed. FIG. 6 is a side view, a right side view, and a plan view, respectively, of the welded joint portion showing the welding method, and FIG. 6 is a plan view of the above according to another previously proposed example. 1a …… Backing body 1b …… Notched opening 1c …… Inner curved surface 1e …… Opening edge 2 …… Incombustible material A …… First rebar A ′ …… Second rebar A ₁ …… First Joint end A ₁ ′ ... second joint end A ₂ ...... first joint groove A ₂ ′ …… second joint groove G …… Gap

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) Bibliography Shou 57-152384 (JP, U) Seki 50-43541 (JP, Y2)

Claims (2)

[Claims] 1. A first reinforcing bar and a second reinforcing bar to be welded,
The joint groove portion is in a state of being continuously connected in opposition with a predetermined separation distance, and extends over the first and second joint end portions of the first and second rebars, and has a ceramic cutout cylindrical shape. With the inner peripheral curved surface of the backing body set as a fitted state,
A notch opening for welding work is opened between the opening end edges of the backing body, and is formed between the inner peripheral curved surface of the backing body and one or both outer peripheral surfaces of the first and second reinforcing bars. By filling a non-combustible material having a heat-melting property in the gap, and inserting a welding tool through the cutout opening, and welding between the joint groove portions such as the first and second reinforcing bars, By the molten metal generated by the welding operation,
A welding method using a backing member of a reinforcing bar joint part, characterized in that the non-combustible material is melted, and then the ceramic backing body is crushed and removed. 2. A longitudinal reinforcing bar state in which a first reinforcing bar having an upper large diameter and a second reinforcing bar having a lower small diameter to be welded are joined to each other with their joint groove portions facing each other with a predetermined separation distance. There
Between the first and second joint ends of the first and second reinforcing bars, the inner peripheral curved surface of the ceramic notched cylindrical backing body is set in a fitted state, and between the opening edge edges of the backing body. A notch opening for welding work is opened, and a gap formed between the inner peripheral curved surface of the backing body and the outer peripheral surface of the second reinforcing bar is filled with a non-combustible material having heat melting property. By inserting a welding tool through the cutout opening and welding between joint groove portions such as the first and second reinforcing bars, the noncombustible material is melted by the molten metal generated by the welding operation. Then, the above-mentioned backing body made of ceramics is crushed and removed, and a welding method using a backing member of a reinforcing bar joint portion.