A kind of repair method of aluminum and aluminum alloy welding seam

Abstract

The invention relates to a technique for reworking a welding seam of an aluminum and aluminum alloy apparatus or pipeline. The method for reworking a welding seam of aluminum and aluminum alloy comprises the following steps: 1) determining the position of a welding defect at the welding seam of a weldment, and forming a penetrating opening in the position of the defect, wherein the opening is provided with a groove, and the clearance of the groove is less than or equal to 8 millimeters; 2) mounting a fixed or movable temporary pad at the opening on the inner wall of the weldment, and ensuring that the pad is tightly attached to the inner wall of the weldment, wherein the pad is made of a nonmetal or metal material of which the melting point is higher than that of the aluminum or aluminum alloy weldment, the pad can not burn in the welding process, and the pad and the aluminum or aluminum alloy can not be subjected to mutual dissolution in the welding process; 3) performing root pass welding in an argon tungsten-arc welding manner; and 4) performing filling pass and capping pass welding in an argon tungsten-arc welding manner. The method can effectively solve the problem on welding reworking of aluminum or aluminum alloy, raise the reworking qualification rate and reduce the reworking frequency.

Description

technical field [0001] The invention relates to a welding method for aluminum and aluminum alloys, in particular to a weld repair process for aluminum and aluminum alloy equipment or pipelines, which is suitable for repairing deep-buried weld defects of industrial pure aluminum and aluminum alloy equipment or pipelines welding. Background technique [0002] Because aluminum and aluminum alloys have good corrosion resistance and will not have iron-contaminated materials; they have ultra-low temperature performance (even at -269 ° C, there is no brittle transition); the use of it to manufacture equipment and pipelines has the characteristics of the lightest relative weight, etc. Therefore, it is widely used in equipment and pipeline engineering in petrochemical, metallurgy, electric power, shipbuilding and other industries. For example: at present, the equipment and pipelines of most air separation plants are mainly made of aluminum alloy materials; the corrosive material sto...

AI Technical Summary

Problems solved by technology

When performing welding repairs for these defects, as the number of welding repairs for aluminum welds increases, the grains of the welds become coarser, and the welds are repeatedly heated to cause their softening degree to increase, which not only affects the strength of the joints, but also makes it more and more difficult to form the welds , welding defects also increase

Therefore, the occurrence of new defects in the rework process has become a very troublesome problem for aluminum and aluminum alloy welding rework, and as the number of rework increases, the probability of new defects also increases

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