Laser welding method for reactor core wrapping tube

Abstract

The invention relates to the technical field of material welding and discloses a laser welding method for a reactor core wrapping tube. The method includes the following steps: machining I-shaped grooves at 8 portions to be welded on a workpiece of the reactor core wrapping tube, installing the workpiece on an inner supporting tool to form the reactor core wrapping tube with I-shaped welding gaps formed at the 8 portions to be welded of the workpiece, installing the inner supporting tool and an outer supporting tool on the reactor core wrapping tube, conducting manual argon arc welding and spot welding to fix the reactor core wrapping tube, conducting laser spot welding on the outer portions of the I-shaped welding gaps in a subsection mode, transversely arranging the reactor core wrapping tube on an idler wheel shelf, adjusting the I-shaped welding gaps to be welded, conducting laser welding on the I-shaped welding gaps to be welded on the reactor core wrapping tube, conducting welding penetration in the one-time welding in the welding process, rotating the reactor core wrapping tube and repeating the last step till the I-shaped welding gaps are all welded. By means of the method, a laser welder molds the welding gaps with thickness as 16mm in a one-time welding penetration mode, and welding efficiency is greatly improved. Due to the fact that the laser welding is small in deformation and even in welding, size accuracy of the welded workpiece is improved, and yield is improved.

Description

technical field [0001] The invention relates to the technical field of material welding, in particular to a laser welding method for a core shroud. Background technique [0002] With the occurrence of Fukushima nuclear safety accident in Japan, the safety of nuclear power has attracted great attention from all over the world; the demand for third-generation nuclear power technology is becoming more and more urgent. In the third-generation nuclear power technology, the welding manufacturing technology of the reactor internals core casing is a difficulty that needs to be overcome urgently. These products are in high temperature, high pressure, and corrosion conditions, and are components that are in direct contact with nuclear fuel rods. Their structural reliability and dimensional accuracy are crucial factors for nuclear fuel safety. [0003] At present, there is no successful case of welding of this kind of products in China. In foreign countries, manual argon arc welding a...

AI Technical Summary

Problems solved by technology

Due to the large structure of the workpiece - the maximum weld length is 4479mm, the nominal wall thickness is 25.4mm, and the wall thickness at the weld is 16mm; the dimensional accuracy is high - the tolerance of the inner shape is +1.4 and -0.76, so the welding workload is large. The welding deformation is large, the size of the welding deformation is difficult to control, and the dimensional pass rate is low

[0004] With the development of laser welding technology, laser welding has been widely used in aerospace, automobile, precision welding and other fields. In recent years, high-power laser welding has developed rapidly, and its power has been increasing. The maximum power has reached 30 kilowatts. At present, it is mainly used in shipbuilding. Fields, but require low dimensional accuracy, and often can only achieve welding of a single structure, poor flexibility

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