ROLLING REDUCTION DISTRIBUTION METHOD IN HOT FREE FORGING

摘要

PURPOSE: A rolling reduction distribution method in hot free forging is provided to increase pressing efficiency on pores generated during casting process in forging process and increase output by minimizing the number of passes using an appropriate rolling reduction distribution method. CONSTITUTION: The rolling reduction distribution method in hot free forging comprises first step of calculating allowable forging load of forging press from dimensions of square bar in the intermediate steel ingot step and target dimensions of the square bar; second step of determining first rolling reduction within the allowable conditions by obtaining deviation of the forging load and allowable forging load calculated in the first step and calculating difference between the maximum rolling reduction and minimum rolling reduction; third step of comparing the first rolling reduction determined in the second step with a reduction ratio having conditions for pressing pores to the maximum determined from a numerical expression for pore pressing ratio; fourth step of determining reduction ratio of the present pass by comparing the reduction ratio determined in the third step with a reduction ratio having allowable limit conditions for generating cracks during forging; fifth step of calculating output side thickness, width spreading, output side width and temperature of the next pass from the reduction ratio determined in the fourth step; and sixth step of repeating the first to fifth steps in calculating reduction ratio of the remaining next passes in the same manner.