JPS61140388A - Electron beam welding method - Google Patents

Abstract

PURPOSE:To reduce the manhour in welding and the cost by providing the copper plate for cooling to cover a welding part and its back side and by moving with setting to the progress of the weld. CONSTITUTION:The copper plate 8 for cooling of rectangular frame shape is fitted freely alidably in the welding direction on the outer periphery of base metals 2, 2. The copper plate 8 for cooling has the hollow section to circulate the cooling water on the inner part and projection shaped mold parts 8-1, 8-2 of proper excess metal shape are formed on its upper and lower faces. The electron beam gun is moved along the groove slit 10 and the copper plate 8 for cooling is moved as well at the same sped from its rear part. The copper plate 8 forms proper surfaces excess metal beads 3, 4 simultaneously melting and joining of the base metals 2, 2 by the electron beam 1. The undercut of beads, etc. are reduced and the manhour in welding can be out off with this method. The cost reduction by the disuse of attached equipment is enabled further.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention particularly relates to an improvement in an electron beam welding method for H plates made of materials with high flowability such as stainless steel, aluminum alloys, and low melting point alloys. be.

<Prior art> In Fig. 3 and Fig. 4, which show an example of the penetration shape of the base material by downward and horizontal penetration or partial welding electron beam welding, respectively, 01 and Ola are electron beam welding, 02
．． 02a is base material, 03.03a is weld metal, 04.04
a is a heat-affected zone, and 05a is a bead drip prevention plate.

For example, in the case of FIG. 3, the heated and accelerated electron beam O1 is focused on the surface or inside of the base material 02.02,
Weld the base material 02.02 and perform deep penetration welding.
As a result, a welded metal portion 03 and a heat-affected zone 04 of a fixed shape are formed due to relationships such as surface tension and gravity.

However, especially when the base material is a material with high fluidity such as stainless steel, aluminum alloy, or low melting point alloy,
The influence of gravity is large, causing undercuts on one surface bead and grape-like beads on the back surface, and in some cases, blow-through occurs, making sound welding difficult.

Conventionally, attempts have been made to solve the above problems by limiting the welding heat input, increasing the amount of molten metal by adding filler wire, or performing multilayer bus welding.

<Problems to be Solved by the Invention> However, the above method of limiting welding heat input has the disadvantage that the required penetration depth cannot be obtained when deeper penetration than the output of the electron beam welding device is required. Furthermore, the method of increasing the amount of molten metal by adding filler wire has the disadvantage that additional wire feeding equipment is required and that it is difficult to control the feeding speed. Furthermore, the multi-pass welding method described above has the disadvantage that the number of welding steps increases as the number of passes increases.

In the case of horizontal welding as shown in Fig. 4, base metal 02a,
When the plate pressure of 02a increases, the welding heat input increases in order to obtain the required penetration depth, and the weld metal 03a tends to drip down particularly on the surface bead side, resulting in a large undercut. Therefore, as shown in the figure, the electron beams on the front and back surfaces are
A bead dripping prevention plate 05a is installed a few mm directly below the irradiation position 1a, but even this cannot completely prevent bead dripping, and especially with materials with high flowability, a large undercut may occur. result in a cut.

For this reason, repair welding is currently performed after welding.

The present invention has been made to effectively solve the above-mentioned problems, and its purpose is to reduce surface damage due to bead dripping that occurs when electron beam welding thick plate materials with high flowability. The purpose is to prevent under-force and back side grape-like beads, thereby reducing welding man-hours and eliminating the need for attached equipment.

In order to achieve the above-mentioned object, in the present invention, a cooling copper plate having an appropriately shaped mold part covering the front and back surfaces of the welded part is moved in accordance with the progress of electron beam welding. It is.

<Example> An example of the present invention will be described below based on the accompanying drawings.

1 and 2 are perspective views showing downward penetration welding and lateral penetration welding, respectively, according to the method of the present invention.

In FIG. 1, reference numerals 2 and 2 are thick plate base materials placed on a moving table 9, which are brought together and groove slits IO are formed in the mating surfaces. As shown in the figure, a cooling copper plate 8 having a substantially rectangular frame shape is provided on the outer periphery of these base materials 2, 2.
is fitted to be slidable in the welding direction of the base metals 2, 2 (in the direction of the arrow shown in the figure), and on the upper and lower surfaces thereof, there is a mold part 8-1. is formed. Moreover, this cooling copper plate 8 has a hollow rectangular cross section,
The inside of this is configured to allow cooling water to flow therein, and a cooling water supply vibro and a cooling water discharge vibrator 7 are connected to this. In addition, these cooling water supply, discharge vibro,
7 is connected to a cooling water supply facility (not shown). or,
The cooling copper plate 8 is supported by an electron beam gun or chamber (not shown), and a sufficient insulation shield is provided between the cooling copper plate 8 and the electron beam gun or chamber.

Therefore, if the electron beam gun is moved along the groove slits 10 of the base materials 2, 2 while circulating the cooling water in the cooling copper plate 8, the cooling copper plate 8 will also be moved from behind at the same speed. Moving. Then, the electron beam 1 emitted from the electron beam gun is irradiated to the groove slit portion 10 of the base materials 2, 2, melting the base materials 2, 2 and joining them, but from the rear of the electron beam gun. In order to slide the cooling steel plate 8 that circulates cooling water inside, the cooling copper plate 8 solidifies the molten metal, and also solidifies the molten metal in the mold portion 8-1.
Proper surface reinforcement bead 3 and back surface reinforcement bead 4 are formed at 8-2. In addition, in the figure, 5 is a heat affected zone.

As a result of the above, undercuts on the front and back beads that occurred during thick plate welding, especially with materials with high flowability,
Grape beads can be eliminated. In addition, this effect can be achieved without using conventional methods such as limiting welding heat input, increasing the amount of molten metal by adding filler wire, or using multi-layer pass welding, which reduces welding man-hours and reduces the need for attached equipment. Cost benefits associated with abolition can be obtained.

On the other hand, in the horizontal penetration welding shown in No. 2 I2I, welding can be performed in exactly the same manner as described above, and the same effects can be obtained. That is, in Fig. 2, 1a is an electron beam, 2a
, 2a is a thick plate base material, 3a is a surface reinforcement bead, 4a is a back reinforcement bead, 5a is a heat affected zone, 8a is a cooling water supply pipe, 7a is a cooling water discharge pipe, 8a is a cooling copper plate, 8a −
1, 8a-2 is an overfill shape mold part, 9a is a moving table,
10a is a groove slit.

The method of the present invention can be applied to any shape of the base material as long as the cooling copper plate is prepared in accordance with the surface shape of the base material.

<Effects of the Invention> As is clear from the above explanation, according to the present invention, the cooling copper plate having the proper overflow shape mold is moved in accordance with the progress of welding. Even when welding thick plates, it is possible to prevent the bead from dripping and obtain an appropriate excess bead, resulting in a reduction in welding man-hours and
Cost reductions can be achieved by eliminating attached equipment.

[Brief explanation of drawings]

1 and 2 are perspective views showing downward penetration welding and lateral penetration welding by the method of the present invention, respectively. FIGS. 3 and 4 are perspective views showing downward penetration welding and lateral penetration welding by the conventional method, respectively. . In the drawings, 1.1a is the electron beam, 2.2a is the thick plate base material, 3.3a is the front reinforcement bead, 4.4a is the back reinforcement bead, 5.5a is the heat affected zone, and 6.6a is the cooling. Water supply pipe, 7.7a is a cooling water drain pipe, 8-8a is a cooling copper plate, 8-1.8-2.8a-1, 8a-2 is a mold part with extra buildup shape, 9.9a is a moving table , 1G, 10a are groove slits.

Claims (1)

[Claims] In an electron beam welding method in which the required welding is performed by focusing the electron beam emitted from an electron beam gun and irradiating it to the welding part, a cooling copper plate having a mold part with an appropriate reinforcement shape that covers the welding part and the back side of the welding part is used. An electron beam welding method characterized in that the electron beam is moved in accordance with the progress of electron beam welding.