Welding flux for X100 pipe line steel submerged arc-welding and preparation method thereof

Abstract

The invention discloses a welding flux for X100 pipe line steel submerged arc-welding and a preparation method thereof. The welding flux comprises, in percentage by weight, main components including 5-13% of SiO2, 26-40% of MgO, 15-24% of Al2O3, 18-25% of CaF2, 1-4% of CaO, 4-8% of MnO, 1-2% of Na2O, 1-2% of K2O and 1.0-6.0% of TiO2, and a bonder accounting for 15-20wt% of the total weight. The preparation method comprises the steps of: uniformly mixing the main components according to proportions; then adding the bonder for pelleting; and baking at low temperature, sintering at high temperature and sifting. When the welding flux is matched with a special welding wire CHW-SG10, a soldered seam has excellent performances, such as high strength, high toughness, better corrosion resistance, lower rigidity and the like approaching to those of an X100-level steel pipe body, and the welding flux can be used for carrying out single or multiple-wire welding and internal and external high-speed welding; and a multiple-wire large-line energy welding speed can reach 120 m / h, and the soldered seam performance and air holes, slag inclusions, cracks, appearance edge, undercut and the like of the soldered seam all meet the requirements of the technical standard of the X100 pipe line steel submerged arc-welding.

Description

technical field [0001] The invention belongs to flux used in metal material welding production process and its production method. Using the flux together with special welding wire can not only carry out single-wire welding, multi-wire welding and internal and external high-speed welding of X100 grade steel, but also meet the requirements of welding into pipes. (Body) rear weld has excellent properties such as high strength, high toughness, better corrosion resistance and lower hardness similar to that of the pipe (body) body. Background technique [0002] As an efficient and clean energy, natural gas is attracting more and more attention. Since natural gas fields are generally located in desert areas far away from the consumer market, how to safely and economically transport natural gas to the consumer market has always been one of the key issues in the development of the natural gas industry. Pipeline transportation is the most ideal transportation method for long-distance...

AI Technical Summary

Problems solved by technology

The applicant disclosed in the patent literature with the publication number CN101444877A and the invention name "X80 grade steel oil and gas conveying pipe submerged arc welding flux" that the weight percentage content of each component in the main component is: SiO 2 14-17%, MgO 20-25%, Al 2 o 3 24-26%, CaF 2 27-33%, CaO 3-6%, MnO 1-3%, Na 2 O 2-5%, TiO 2 1.0-2.0% flux, the flux and the matching submerged arc welding wire are used for welding X80 grade steel oil and gas pipelines, although the weld seam has the same high strength, high toughness, Good corrosion resistance and low hardness and other excellent properties; but if it is used for welding of X100 pipeline steel, the composition of the weld seam is quite different from that of the pipe (body) body, and it is far from meeting the requirements of X100 pipeline steel. Requirements for weld strength, toughness, corrosion resistance, etc.