JP2002224824A - Method for cooling weld zone for arc welding - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the working efficiency of a welding work by increasing the cooling rate of a weld zone in an arc welding work of the joined part of a connection of a column and a beam. SOLUTION: In the joining work with the arc welding of the joined part C of the connection of the column 1 and the beam 2 which are members of a steel-frame structure, a cooling device 4 which contains water W, which is made of a material which has excellent thermal conductivity, is positioned on the upper face 21A of the flange 21 of the beam 2 and away from the arc weld zone by a prescribed distance, so that the temperature drop at the weld zone is promoted and the waiting time of welding for the subsequent pass is shortened.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for cooling a weld for arc welding.

[0002]

2. Description of the Related Art When constructing a steel-framed building or the like, a beam end flange of a beam-column joint, which is a steel frame member, is generally joined by arc welding at a factory or a site. When welding is performed in a state where the inter-pass temperature is high, such as by performing continuous arc welding, the temperature around the weld increases and the cooling rate of the weld metal slows down, reducing the strength and toughness of the weld. There is a problem that it is lowered.

[0003] In order to solve the above-mentioned problems, it is important to appropriately manage the heat input of the welded portion and the upper limit of the interpass temperature after the revision of the Japanese Industrial Standard (JIS) and the Enforcement Order of the Building Standards Law. Therefore, it is required to control the temperature of the welded portion so as to perform welding without exceeding the upper limit value. Therefore, if the temperature around the weld immediately before the start of the next pass is not sufficiently lowered, conventionally, the weld is left unattended and the operator waits for the weld to cool down naturally before the worker We are beginning to work on welding.

[0004]

Therefore, in the case of an operation in which the temperature of the weld is likely to increase, such as a multi-pass welding operation, the temperature around the weld is excessively increased and the cooling rate of the weld is reduced. It will be late. For this reason, it takes time for the weld to cool down naturally and the temperature between passes to drop sufficiently, and the waiting time until the next pass is welded must be lengthened. There is a problem that time is prolonged and work efficiency is not good.

It is an object of the present invention to provide a method for cooling a weld for arc welding, which can solve the above-mentioned problems in the prior art.

[0006]

According to the present invention, in order to solve the above-mentioned problems, a joint portion between a column and a beam and a joint portion between a beam and a beam, which are steel frame members, are joined by arc welding. A method of cooling an arc welded part, wherein, when performing the arc welding, a cooler made of a material having good heat conductivity containing a cooling liquid is provided on the flange of the beam and the arc welded part is cooled. A method of cooling a welded portion for arc welding, characterized in that the method is installed at a position separated by a predetermined distance from the welding portion.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a side view of a joint for explaining an embodiment in which a column and a beam, which are steel frame members, are joined by welding by applying the method of the present invention. .

Referring to FIG. 1, a column 1 and a beam 2 using the present invention.
The procedure for welding the connection joint with the above will be described. First, a column 1 made of a rectangular steel pipe is vertically fixed at a required position. Next, after assembling the beam 2 made of H steel using a surface plate (not shown) or a jig (not shown) or the like so as to be horizontal at a predetermined position with respect to the side surface 1A of the column 1, The tack welding of the column 1 and the beam 2 is performed using the welding machine 3. Then, after the cooler 4 in which the water W is injected is directly placed on the upper surface 21A of the flange 21 of the beam 2 of the connection joint C, the cooler 4 is installed.
Perform the main welding work.

FIG. 2 shows the cooler 4 on an enlarged scale. The cooler 4 is provided with a main body 41 which is a hollow body having a rectangular parallelepiped shape for containing water or other appropriate cooling liquid. Opening 42 for injecting the cooling liquid or discharging the cooling liquid contained in the main body 41
Is provided. In the present embodiment, the opening 42 is provided at one end of the main body 41 as a square tubular member integrally extended so as to rise in a chimney shape.

The main body 41 and the opening 42 are made of a rigid material having good thermal conductivity such as iron, copper, and aluminum.
The lower surface 41B of the main body 41 is a flat surface. Thereby, when the cooler 4 is installed on the upper surface 21A of the main body portion 41, a good contact state is obtained between the lower surface 41B and the upper surface 21A, and the heat transfer between the two is extremely well performed. I have.

The opening 42 for injecting and discharging the cooling liquid has a considerably smaller opening area than the area of the upper surface 41A. The configuration is useful for keeping the amount of evaporation small. In addition, in order to increase the cooling effect of the cooler 4, it is preferable that the width X of the main body portion 41 be approximately the beam width.

The position where the cooler 4 is installed is as follows (1)
When performing the welding operation, the cooler 4 is not too close to the welded portion so that the welding torch 31 of the welding machine 3 does not contact the cooler 4 and hinder the work. (2) The cooler 4 The cooler 4 is close enough to the weld to the extent that the water W that has entered can be effective in preventing the rise in temperature of the weld, (3) but with a very hot weld. The temperature gradient between the part where the cooler 4 containing the water W is installed and the flange 21 becomes sharp, and the flange 21
In addition, if the cooling rate of the weld metal is excessively high, defects such as cracks due to the hardening of the welded portion are likely to occur. It is desirable to satisfy the condition that they are apart from each other.

Water W is injected into the cooler 4 configured as described above, and as shown in FIG. 1, the water W is placed on the upper surface 21A of the flange 21 of the beam 2 and at a position satisfying the above conditions. By performing the welding work of the connection joint C between the column 1 and the beam 2 in a state where the cooler 4 into which W is injected is installed, a part of the heat generated in the welded portion by the cooler 4 is favorably absorbed. . Therefore, the rise in temperature of the welded portion can be suppressed and the cooling of the welded portion can be promoted, so that the rate of temperature decrease after the end of the welding operation for each pass of the welded portion is increased, and the time until the next pass is welded Since the waiting time can be shortened, the work efficiency of the welding work of the connection joint C can be increased.

At the joint C, the lower flange 22
When performing the welding work, the cooler 4 ′ into which the water W is injected
As shown by the two-dot chain line in FIG. The same effect as in the above-described case in which the cooler 4 is installed on the upper surface 21A of the flange 21 to weld the flange 21 can be obtained. The width of the cooler 4 'when installed on the upper surface 22A of the lower flange 22 is as follows:
Since the web 23 is provided at the center of the flange 22, it is necessary to reduce the width to about half of the width X of the cooler 4. In the example shown in FIG. Two vessels 4 'are installed.

Further, since the cooler 4 can be carried alone by an operator, it can be easily installed at a required position on the upper surface 21A of the flange 21 of the beam 2 to be welded. Alternatively, it can be removed and used immediately after the welding operation is completed, so that it can be conveniently used to cool the weld both in the factory and on site. The same applies to the cooler 4 '.

As described above, if the welded portion of the joint portion C is cooled by using the cooler 4, it is possible to perform the welding without increasing the strength and the toughness of the weld metal while improving the working efficiency. can do.

In order to enhance the cooling effect of the cooler 4, for example, a plurality of cooling fins may be provided on the upper surface 41A of the cooler 4. In order to further enhance the cooling effect of the cooler 4, in addition to the cooling fins, the main body 41
May be further provided with a blower to blow air from the blower to the cooling fins.

[0019]

According to the present invention, it is possible to perform a welding operation of a joint between a column and a beam in a state where a cooler into which a cooling liquid has been injected is installed at a predetermined distance above the flange of the beam. As a result, a part of the heat generated in the welded part is absorbed by the cooler, and the inter-pass temperature can be reduced quickly, so that the welding work can be effectively performed at a high inter-pass temperature. Can be prevented. Therefore, a rise in the temperature of the welded portion can be suppressed, and cooling of the welded portion can be promoted, so that the waiting time until the next pass welding is performed can be reduced, and the time required for the welding operation can be reduced. Work efficiency can be increased.

Further, the cooler used in the method of the present invention can be made large enough to be carried by an operator alone, so that the cooler on the upper surface of the flange of the beam of the welded portion can be used. It can be easily installed and removed at the required position, can be easily used for the next weld after the welding work is completed, and no power source for circulating water is required Therefore, it can be conveniently used to cool the weld both in the factory and on site.

Further, it is possible to perform welding without reducing the strength and toughness of the weld metal while improving the working efficiency by cooling the welded portion.

[Brief description of the drawings]

FIG. 1 is a side view of a joint for explaining an example of an embodiment in which a column and a beam, which are steel frame members, are jointed by welding by applying the method of the present invention.

FIG. 2 is an enlarged perspective view of the cooler of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Column 2 Beam 3 Welder 4, 4 'cooler 21, 22 Flange 21A, 22A Upper surface 31 Welding torch 41 Main unit 41A Upper surface 41B Lower surface 42 Opening C Connection joint W Water

Claims (1)

[Claims] 1. A method of cooling an arc welded part when a joint part between a column and a beam and a joint part between a beam and a beam, which are steel frame members, are joined by arc welding. In the case of performing, a cooler made of a material having good thermal conductivity containing a cooling liquid is provided on the flange of the beam and at a position away from the arc weld by a predetermined distance. Method of cooling the weld for arc welding.