Large forged components are mostly key components in mechanical equipment, with particularly strict quality requirements. In addition, due to large volume, large size, complex production processes, and various factors that affect the quality of large forged components, defects and wastes are easily generated, resulting in significant economic losses.
The defects of large forgings are closely related to the metallurgical quality and production process of the spindle. Generally speaking, steel ingots are the foundation for the production of large forgings. Advanced and reasonable hot forging technology is an important guarantee for the production of large forgings.
The key to the quality of large forgings is: excellent metallurgical technical quality; A well-proportioned and dense tissue; Qualified mechanical and technical performance; Excellent dimensional accuracy with minimal drawbacks. To improve the quality of large forgings, it is necessary to improve the purity of liquid steel. For example, using smelting outside the furnace to reasonably remove gases, non-metallic material inclusions, and harmful trace elements from the steel, adjust the chemical substances and copper discharge temperature, and then clean and pour to maintain the purity of the steel. Secondly, it is necessary to select a reasonable ingot type, manipulate the solidification state, and obtain ideal crystals, thereby greatly improving the quality of the forging raw materials. Subsequently, reasonable heating is required to not only improve the process plasticity, but also avoid defects such as cracks, coarse grains, overheating, and underheating for molding.
Large forgings are not only molded to achieve the desired shape and size, but also more critical is to break the as-cast coarse grains, compress the structure, obtain reasonable fiber distribution, improve engineering research performance, properly manipulate the cooling and heat treatment of the forging, be able to enhance crystal particles, improve the mechanism, remove stress, prevent white spots, adjust characteristics, and consider strengthening and toughening regulations.
Due to the multiple production processes, long cycles, high consumption of raw materials, energy, and labor, and high production costs of large forgings, improving the qualification rate of large forgings, detecting defects in a timely manner, classifying the causes, and taking countermeasures to prevent and rescue them have become a very important link in the production process of large forgings.