21/4Cr-1Mo-1/4V steel forging and automatic temperature-control inflation three-dimensional circulating water rapid cooling thermal treatment method thereof

Abstract

The invention discloses an improved 21 / 4Cr-1Mo-1 / 4V steel forging which is characterized by comprising the following components in percent by weight: 0.11-0.15 percent of carbon, not more than 0.10 percent of silicon, 0.30-0.60 percent of manganese, not more than 0.01 percent of phosphorus, not more than 0.01 percent of sulfur, 2-2.5 percent of chromium, 0.9-1.10 percent of molybdenum, not more than 0.20 percent of nickel, not more than 0.15 percent of copper, 0.25-0.35 percent of vanadium, not more than 0.30 percent of titanium, not more than 0.002 percent of boron, not more than 0.07 percent of niobium, not more than 0.015 percent of calcium and the balance of iron. The invention also discloses an automatic temperature-control inflation three-dimensional circulating water rapid cooling thermal treatment method of the steel forging, which comprises the steps of: 1, an after-forging thermal treatment process: normalizing at a temperature of 890-990 DEG C, air-cooling after constant temperature is not less than 1h / 100mm, tempering at a temperature of 680-720 DEG C, furnace-cooling after constant temperature, and cooling at a limited speed at a temperature of below 400 DEG C; 2, a thermal refining process: quenching at a temperature of 900-980 DEG C, carrying out constant temperature with 1h / 100mm, rapidly cooling and quenching and tempering at a temperature of 680-720 DEG C, carrying out constant temperature with 1h / 100mm and air-cooling thickness of the forging, wherein the water temperature of thickness of the forging is not more than 10 DEG C; and 3, adopting a three-dimensional automatic control circulating water periphery inflation method. The forging has higher tension strength, temper brittleness resistance, hydrogen damage resistance and lower long-term high-temperature damage sensitivity.

Description

technical field [0001] The invention relates to a heat treatment method for a chrome-molybdenum steel forging used in a pressure vessel, in particular to an improved 21 / 4Cr-1Mo-1 / 4V steel forging used for a hydrogenation reactor in the petrochemical industry and its automatic temperature-controlled inflatable stereo Circulating water rapid cooling heat treatment method. Background technique [0002] Chromium-molybdenum steel plus vanadium steel forgings are mainly used in hydrogenation reactors in the petrochemical industry. It is an important device for hydrocracking, refining, hydroreforming, desulfurization, and heavy metal removal. In actual production, in order to achieve low-cost and high-efficiency hydroprocessing, a relatively high service temperature (generally above 400°C) is usually used, and the hydrogen partial pressure is > 10mpa0. The medium in contact with the hydrogenation reactor is mostly oil, gas and hydrogen. , hydrogen sulfide and other corrosive su...

AI Technical Summary

Problems solved by technology

In order to improve the working efficiency of hydrocracking and hydrocracking desulfurization, it is necessary to increase the volume and capacity of the hydrogenation reactor, and at the same time increase the working pressure and temperature, then the damage and corrosion caused by long-term service in a severe environment will inevitably lead to reaction The performance of the reactor material is reduced, and the service life is reduced, which promotes the continuous improvement of the hydrogenation reactor manufacturing technology

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