RU1818187C - Method of electron-beam welding - Google Patents

Abstract

Usage: when welding joints of complex spatial configuration. SUMMARY OF THE INVENTION: welding is performed by two electron beams intersecting at an angle with their alternating switching on. In this case, the switching of the rays is carried out in the section of the junction section, where the normal to the midline of the section coincides with the bisector of the angle of intersection of the rays. The point of intersection of the rays is additionally moved relative to the joint with a simultaneous change in the angle at the apex of the intersecting rays. In the concavity areas of the joint, the point of intersection of the rays is located at or behind the joint surface distant in the direction of the rays, and in the areas of convexity, on or in front of the joint surface. 2 s.p. f-ly, 3 ill. fc w 6

Description

The invention relates to electron beam welding, and more specifically to a technology for welding joints of complex cross-section with two intersecting beams.

The aim of the invention is to improve the quality of weld formation by spatial reorientation of the weld pool directly during the welding process.

Figures 1-3 show a flow diagram of a method as applied to a heavy plate joint.

The electron beam 1 and electron beam 2, respectively formed by emitters (electron beam guns) 3 and 4, intersect at point O, the path of which during welding passes through the cross-sectional body from the farthest relative to emitters 3 and 4

surface W of junction 5 to the near surface Zh (also relative to emitters 3 and 4).

In the concavity sections of the joint with respect to the emitters, the weld pool is reoriented when the point O is located on or behind the surface О, and in the convexity sections of the weld joint, the weld pool is reoriented when the point О is located on or in front of Ж. The magnitude of the excess of the point O behind the surfaces W and G is determined by the condition of guaranteed overlap of the welds being welded by various beams.

When welding thin-sheet joints (5 - 10 mm), it is allowed to reorient the weld pool at the location

00

with

00 h |

points О on the midline of the section (joint thickness). In Fig. 1, the middle line is indicated by S.

Behind junction 5 there is a target - collector 6 for damping the power of beams 1 and 2 passing through junction 5.

The letters A, B and C mark the zones where the joint is welded separately by alternating beams 2, 1 and 2, respectively. The combinations of letters AB and BV indicate the zones of joint action of two beams - the zone of reorientation of the weld pool.

The same indices in Fig. 1 mark the positions of the axes of the beams 1 and 2 and the positions of the emitters 3 and 4 during welding of the corresponding zones of the joint 5.

At section A, the joint 5 is welded by the emitter 4. The electron beam 2 operates in a predetermined mode before the start of section AB. Then, when the emitter 4 is operating (beam 2), the emitter 3 (beam 1) is turned on and only after the power of the electron beam 1 has reached the mode, which ensures full penetration of the thickness of the junction section, the power (current) of beam 2 is reduced to zero using techniques that prevent the formation of craters (oscillations, defocusing, etc.).

The rate of rise of the electron beam included in the operation should substantially exceed the rate of decline of the electron beam being turned off. Their values depend on the thickness of the metal being welded, the welding speed, the thermophysical properties of the metal being welded, etc. and determined by the welding mode.

In section AB, the joint is welded with two beams 1 and 2 (both emitters 3 and 4 work). A more detailed diagram of the passage of beams 1 and 2 along the junction 5 in the reorientation zone of the weld pool is shown in Fig. 2. A section of the concavity of the joint with respect to emitters 3 and 4 is considered. The direction of action of the rays 1 and 2 forming the weld pool in the joint 5 is shown by the corresponding shading (without taking into account the displacements introduced by the inertia of the process and the welding speed), where

SOD - zone of complete penetration of the joint by beam 2 and partial penetration of beam 1.

DOE - zone of complete penetration of the joint by beam 1 and beam 2.

EOF - zone of complete penetration of the joint by beam 1 and partial penetration of beam 2.

In section B, the joint 5 is welded by the emitter 3 (beam 1). Welding is performed similarly to section A.

At the BV site, the joint is welded with two beams 2 and 1 (both emitters 4 and 3 work). A more detailed diagram of the passage of rays 2 and 1 at the junction 5 in the zone

reorientation of the weld pool at the site of the convexity of the joint relative to the emitters 4 and 3 is shown in Fig.Z. The direction of action of the rays 2 and 1 forming the weld pool at the junction 5 is shown corresponding

hatching (excluding displacements introduced by the inertia of the process and welding speed), where

LKO - zone of complete penetration of the joint by beam 1 and partial penetration of beam 2.

CBS - zone of complete penetration of the joint by beam 2 and beam 1.

OGP zone for complete penetration of the joint by beam 2 and partial penetration of the beam 1.

At section B, the welding of the joint 5 is carried out by the emitter 4 (beam 2). Section B corresponds to section A and then the sequence of alternating beams is repeated.

Alternating work schemes of beams 1 and 2,

providing a reorientation of the weld pools shown in figure 2 and fig.Z are not equivalent. If, in Fig. 3, reorientation of the weld pool on the convex section of the joint is ensured with the guarantee of overlapping of the seams formed by various beams (section OP), then in Fig. 2, overlapping of the joints in the region of the point is critical. In this case, for guaranteed overlap of the seams (in the concave section)

it is necessary: either to place the point of intersection of rays 1 and 2 behind surface III, moving it in a straight line MN towards M, or at a rate of increase in the current of the switched-on beam, start switching on a little earlier, i.e. increase the length of the LED, or with a delay (later) begin to reduce the current of the switched-off beam, i.e. Leah Lich segment of EG.

The proposed welding method provides high-quality welds at the joints of a complex section, especially complex joints having sharp bends of the contour of the section.

The most effective method for welding particularly complex joints including joints of developed section, the high-quality performance of which is possible only when using high-voltage emitters with a voltage of over 60 "V, i.e. emitters

Claims (3)

having a significant mass and manipulation of which relative to the joint is practically impossible .- Formula 1. The method of electron beam welding  TWO intersecting electron moons, set at an angle to one another, characterized in that, in order to improve the quality of the formation of the seam, when welding joints of complex cross-section, welding is performed by alternating the inclusion of beams, and their switching is carried out in sections of the cross-section of the joint, which have normal to the mid-section line coincides with the bisector of the angle at the apex of intersecting rays. 2. The method according to claim 1, characterized in that during the welding process the angle of intersection of the rays is changed. 3. The method according to claims 1 and 2, characterized in that in the concave sections of the junction rays positioned with their intersection at the far in the direction of action of surface rays junction or behind it. and in the areas of bulge on the near surface of the joint or in front of her. ABOUT L V / / -fa / V / y / 35 / f U / X L t L 6v 3 / / X   t L / Fig.Z.