The invention discloses a trapezoidal blank manufacturing method, and relates to the technical field of free
forging. The method comprises the following steps that 1, blanking is conducted, specifically, qualified
forging rods are selected, and blanking is conducted according to the fixed specification and weight; (2) heating: heating the
forging rod to 830 DEG C, charging the forging rod into a furnace, and then preserving the heat of the forging rod; an upper anvil and a lower anvil are preheated to 200-300 DEG C in advance, the upper anvil face and the lower anvil face are permitted to be preheated through a preheated blank, forging is conducted after the blank reaches the temperature, and the forging process comprises local upsetting, local drawing-out, flattening and shaping. The forming die forging step is omitted, a special die does not need to be designed, the time for designing and
machining the die is saved, the
production cycle time is shortened, the step is simplified, the forging difficulty is lowered, the
production rate is increased, forming can be achieved only through one heating number in the whole deformation process, and the production efficiency is improved. The influence of repeated heating on the product quality is reduced, the energy waste is reduced, and the production cost is reduced.