Sintered flux for 9Ni steel welding and preparation method thereof

Abstract

The invention discloses sintered flux for 9Ni steel welding, and relates to the technical field of welding materials. The sintered flux comprises the following components in parts by weight: 20 to 28 parts of CaF2, 23 to 33 parts of MgO, 15 to 18 parts of Al2O3, 8 to 12 parts of CaO, 4 to 10 parts of SiO2, 0.5 to 2 parts of BaO, 0.5 to 2 parts of TiO, 0.5 to 2 parts of ZrO2, 0.5 to 2 parts of alloy and 15 to 20 parts of water glass, wherein the alloy is ferrosilicon or manganese-silicon or a combination of ferrosilicon and manganese-silicon. The preparation method comprises the steps of uniformly mixing the components according to the proportion; carrying out granulation; drying at the low temperature of 300 to 400 DEG C; and sintering at the high temperature of 660 to 750 DEG C, so as to obtain a flux finished product. According to the sintered flux, the flux is matched with a solid welding wire ERNiCrMo-4, the welding manufacturability is relatively good, the mechanical property of weld joints is good, the ultra-low temperature toughness of deposited metals is stable and excellent, the hot crack resistance sensitivity is good, and the sintered flux is applicable to submerged arc flat welding and horizontal welding of 9Ni steel.

Description

technical field [0001] The invention relates to the technical field of welding materials, in particular to a sintered flux for welding 9Ni steel and a preparation method thereof. Background technique [0002] With the rapid development of my country's economy and the sharp decline of onshore oil resources, offshore oil and gas development has become a hot spot in my country's energy development. As a clean energy, natural gas has been paid more and more attention. In recent years, LNG (liquefied natural gas) projects have developed vigorously. At present, there are many LNG projects planned in China. 9Ni steel is considered fashionable due to its excellent low-temperature toughness and good weldability. Excellent materials for manufacturing cryogenic pressure vessels, the inner tank materials of LNG storage tanks are all made of 9Ni steel without exception. [0003] For the welding of 9Ni steel, domestic related research started relatively late, and some experience has been...

AI Technical Summary

Problems solved by technology

The welding consumables for submerged arc welding of 9Ni steel are mainly ERNiCrMo-4, which is currently all dependent on imports. Although the domestic Harbin Welding Institute, Jingqun, Antai Technology and other units have carried out relevant research, there are no mature products.

At present, there are not many related patents applicable to the submerged arc welding flux for 9Ni steel that requires higher low-temperature impact toughness. The application number 201010292568.7 discloses a sintering flux for 9Ni steel and its manufacturing method. The scope of application and properties of deposited metal are different from those of this patent

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