Welding method for 12Cr1MoV and 07Cr19Ni 11Ti dissimilar steel

Abstract

The invention relates to a welding method for 12Cr1MoV and 07Cr19Ni 11Ti dissimilar steel. In the prior art, austenite and pearlitic steel are mostly welded by adopting constantan welding wires, so that the cost is higher, weld joints are deformed and cracked, and welding in the prior art is not suitable for batch production. The dissimilar steel comprises dissimilar steel A (1) and dissimilar steel B (2), the butt gap b of the dissimilar steel A and the dissimilar steel B is 2.0 mm-3.0 mm, the groove angle a is 30 degrees-35 degrees, the truncated edge p is 1.5 mm-2.0 mm, the thickness delta of a pipe is 5 mm, a TGS-347 welding wire is adopted, the diameter of the welding wire is 2.4 mm, assembling is conducted in a free state during welding, manual tungsten electrode argon arc welding is adopted, an internal wire adding welding method is adopted during bottoming, after the pipeline is filled with argon and is stable, root layer welding is conducted, and the temperature between layers is controlled to be smaller than or equal to 350 DEG C; and the method comprises the steps that firstly, grooves in the base metal sides of the dissimilar steel A and the dissimilar steel B are machined, the surfaces of the grooves and the outer walls, within 10 mm, of the two sides of the base metal are cleaned, and then horizontal fixed welding and vertical fixed welding are conducted. The welding method is used for the dissimilar steel of pearlite steel and austenitic stainless steel.

Description

technical field [0001] The invention relates to the field of welding technology, in particular to a welding method for 12Cr1MoV and 07Cr19Ni11Ti dissimilar steels. Background technique [0002] It is austenitic stainless steel, 12Cr1MoV belongs to pearlitic steel, and the welded joint of 07Cr19Ni11Ti and 12Cr1MoV steel belongs to the welded joint of dissimilar steel, that is, the welding of austenitic and pearlitic steel. In addition, the difference in physical properties is large, and large-area welding defects are prone to occur. In many literatures, Inconel 82 (ERCrNi-3) welding wire is mostly used for welding austenitic and pearlitic steels, and the cost is high. It is not suitable for mass production, and the problems existing in the welding of 07Cr19Ni11Ti and 12Cr1MoV in the prior art: [0003] (1) The dilution effect of the pearlitic steel base metal on the weld and the formation of the M transition layer in the fusion zone: 12Cr1MoV steel has a dilution effect on t...

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Problems solved by technology

[0004] The experience of using dissimilar steel welded joints shows that most of the damage occurs in the fusion zone. Although the weld is A structure, there is a transition layer of martensitic structure between the pearlite base metal and austenite, that is, on the fusion zone. , if austenitic steel and pearlitic steel are welded, a martensite structure with high hardness will appear in the transition layer, and it may cause damage to the fusion zone during welding or use, reducing the reliability of the welded structure. Therefore, welding materials with strong austenitization ability are often selected;

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