In almost all fields of machine manufacturing, forging, especially die forging and precision forging, is an important hot working process. For many years the forged blanks have been heated in a variety of flame stoves. From the 1950s to 1960s, induction heating technology expanded from smelting and heat treatment to the forging field, bringing revolutionary changes to the forging industry. Forging induction heating is one of the main applications of induction diathermy furnace.
Induction diathermy furnace has the following advantages compared with flame furnace:
(1) Saving energy. General induction heating furnace of total efficiency (steel) more than 60%, local heating, compared with other types of furnace heating effect will be more obvious. For example, in the 1980s, a larger crankshaft was forged in a certain factory, the original oil furnace was repeatedly sent to the furnace for overall heating, and then the induction ditherm furnace was used for local heating of each forging section, and the energy consumption was reduced by 20 ~ 30 times.
(2) The products produced are of good quality and uniform. Induction heating is of good quality due to its fast heating rate, fine grain, and light oxidation and decarburization. Because of easy to achieve mechanization, automation production, so the product performance is consistent, good repeatability. An obvious example is that in the 20th century, an Arsenal in China imported high-speed precision forging equipment from an advanced country in Europe, and the other party suggested that an induction diathermy furnace should be equipped at the same time so that the finished products could be forged at one time. Due to the unfamiliar technology, our staff thought it was very simple to heat the furnace to more than 1000 degrees. In order to save the limited foreign exchange, they refused. After returning home, they equipped themselves with a flame furnace. Results Because the heating time is too long, the oxidation burns badly, after forging, not only have to go through grinding and another machining, but also have to carry on pickling. Increased the amount of material reserved, processing hours, and production costs. The capacity of the advanced forging machine is less than 20%. It was not until later that we realized the key to the problem and developed the corresponding induction heating furnace that we could solve it well.
(3) Low processing amount of materials, saving raw materials; Good heating performance can improve the service life of the mold.
(4) high level of mechanization and automation equipment, small volume, less floor space, so easy on the assembly line and automatic line.
(5) Clean energy, good working conditions, basically no high temperature and little environmental pollution.
(6) Fast start and stop, easy to use, and maintain.
According to the preliminary statistics of some enterprises, induction heating can save about 70% of the total production time, the oxide scale is 1/2 ~ 1/4 of the flame furnace, the die life can be increased by 20% in die forging, and the metal saving is 10% ~ 15%.