The invention discloses an extra-thick
hydrogen present 15CrMoR steel plate and a production method thereof. The steel plate comprises the following elements in percentage by weight: 0.12-0.17 percent of C, less than or equal to 0.20 percent of Si, 0.40-0.70 percent of Mn, less than or equal to 0.008 percent of P, less than or equal to 0.003 percent of S, 0.14-0.18 percent of Ni, 0.80-1.20 percent of Cr, less than or equal to 0.10 percent of Cu, 0.45-0.60 percent of Mo, 0.025-0.050 percent of Al, less than or equal to 0.016 percent of As, ess than or equal to 0.008 percent of Sn, less than or equal to 0.003 percent of Sb and Fe and unavoidable impurities in balancing weight. The production method comprises the steps of converter
smelting, LF (
Ladle Furnace) refining, vacuum refining, pouring, heating, rolling, cooling control,
slow cooling, heat treatment and the like. According to the invention, the chemical elements of the steel plate are designed via the Cr-Mo taken as the basic
alloy element, through the converter
smelting, the LF refining, VD (Vacuum Degassing) furnace vacuum
degasification, plate rolling, crack detection, normalization,
tempering, steel plate finishing operation, performance inspection, as well as rolling control, cooling control, normalization and
tempering, the particle size of steel is more than 8.0, and the elements are organized to a
tempering sorbite; and through the effective implement of the measurements, the
hydrogen present steel plate with a thickness of 120 mm to 150 mm and good
corrosion resistance is successfully produced, and the steel plate is provided with higher intensity and good tenacity, and has favorable
welding performance.