Welding electrode for welding -50 DEG C low-temperature pressure container steel

Abstract

The invention discloses a welding electrode for welding -50 DEG C low-temperature pressure container steel. A core wire of the welding electrode is H08E of low S and P; a cover is prepared by the following components in parts by weight: 32-40 parts of marbles, 15-23 parts of fluorite, 4-8 parts of rutile, 5-7 parts of silica powder, 11-15 parts of iron powder, 5-9 parts of silicon iron, 3-6 parts of ferromanganese, 1-3 parts of ferrotitanium, 1.5-2.5 parts of metal nickel, 1-3 parts of phlogopite, 1-2 parts of sodium carbonate, and 0.5-1.0 part of graphite; all the components of the cover are evenly mixed, and 3.2 M pure sodium water glass of 24 weight% by the total weight of the components is added for mixing to prepare the cover; the rest production process of the welding electrode is performed by a conventional technology; the heat treatment is performed after the welding; and the temperature of 620 DEG C is keep for 1 hour, so that the mechanical performance is stable, the tensile strength reaches 560-620 Mpa at room temperature, and the -50 DEG C V-shaped gap impact power reaches above 110 J to satisfy the welding of the -50 DEG C low-temperature pressure container steel.

Description

technical field [0001] The invention belongs to the technical field of welding materials, in particular to an electric welding rod used for welding low-temperature pressure vessel steel at -50°C. Background technique [0002] With the rapid development of my country's petrochemical industry, there is a great demand for various types of large cryogenic pressure vessels used to store liquefied petroleum, natural gas, ethylene, propylene and so on. [0003] 15MnNiNbDR steel plate has the characteristics of low welding crack sensitivity and high strength. It is mainly used in ethylene low-temperature pressure vessels, and the designed service temperature is -50°C. Due to the harsh conditions of use, the requirements for welding conditions are also high, which is mainly reflected in the various components of the welding electrodes. However, the current welding electrodes have poor all-position welding processability, and the deposited metal has poor low-temperature toughness afte...

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Problems solved by technology

Due to the harsh conditions of use, the requirements for welding conditions are also high, which is mainly reflected in the various components of the welding electrodes. However, the current welding electrodes have poor all-position welding processability, and the deposited metal has poor low-temperature toughness after stress-relieving heat treatment. Low, unstable performance, easy to appear low value and other problems, can not meet the design requirements of -50 ℃ low temperature pressure vessel

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