Electric arc furnace fabric and power transmission system have doorways

In the modern large and medium-sized steel casting production enterprises, the electric energy consumption per ton of molten steel in the electric arc furnace is an important energy index. Now we have the experience in the production of 30t electric arc furnace in our company's cast steel business unit, and talk about the relationship between electric arc furnace fabric and power transmission system.

The original cloth method of Harbin Electric Machinery Co., Ltd. simply stipulates that the heavy material is added to the bottom and the upper part is light and thin; the power transmission system is for 5~10min for small current and low voltage, and the highest voltage and maximum after the arc is buried in the scrap. The current is sent and melted, and the oxygen is cut in the middle. After the collapse is completed, the reactor is removed, and the three-stage voltage is supplied, and the current is appropriately adjusted according to the smelting condition.

Tao Shu, Chief Engineer, Thermal Processing Division, Harbin Electric Machinery Co., Ltd.

After the energy management refinement and upgrading, we found that the same material, the same tonnage of smelting furnaces, different time, different power consumption, statistical analysis found that the same charge, the maximum power transmission, the whole furnace for the steel sheet furnace The average average smelting speed is obviously faster than the average melting speed of most risers plus a small amount of waste steel sheet heat, and the uniform melting rate of the charge is faster than that of the furnace. Most of the charge is a riser, with an average power consumption of 20%.

Several comparison tests were conducted for the number of heats that were loaded into large risers. The first group is the highest voltage and maximum current after penetrating the well. The second group is the voltage drop to 2 after the well, the current is reduced by 20%, the melting rate is not significantly different, and the second group of power consumption is reduced by 5% to 10%. .

Our analysis believes that the melting rate of the large riser and the edge of the charge is slow, the power supply is too fast and can not be absorbed quickly, local high temperature, large heat dissipation, resulting in increased power consumption. The adjustment measures are as follows: the feeding material is as stable and uniform as possible, so that the charging material, especially the heavy material, is not biased toward the edge of the furnace body; when the material block is too large, the power supply strength is appropriately reduced.

In the case where the same tonnage, the same furnace charging method and the power transmission mode have appeared in the test, the smelting time is also similar, but the power consumption varies greatly. The maximum energy consumption is 15%. According to the voltage and current loaded into the electric furnace, we calculate the electric energy input into the electric furnace, and find that the electric energy used for melting is basically similar. The difference is that the working time of the reactor is different, because the reactor consumes a part of electric energy, resulting in an increase in reactive power. , resulting in an increase in electricity consumption per ton of molten steel. After a period of statistics, the energy consumption of the furnace with a long period of time is too large. Through reasonable cloth and oxygen blowing, it is possible to advance the time of leaving the reactor and reduce the power consumption of smelting.

The power transmission system of the electric furnace is a main working system used by the electric arc furnace. It should not be static. It should be adjusted according to the specific conditions of the charging materials. The fabric is a basic work and should be strictly according to the smelting characteristics of the electric arc furnace. Prescribe and refine operations.