How to Reduce Energy Consumption and Improve Efficiency of Rolling Mill?

How to improve the operating efficiency of the rolling mill, reduce the energy consumption of the rolling mill, reduce mechanical wear, and prolong the service life of the rolling mill is very important. Various types of rolling equipment are similar. They are heavy-duty equipment with a certain constant torque to meet the requirements of the rolling mill for passing steel. The high current of the rolling mill and the low efficiency of the operation are the main reasons for the serious waste of energy consumption when the rolling mill is working.

Generally speaking, the comprehensive energy consumption per ton of steel in the rolling process includes three aspects: electricity consumption, fuel consumption, and oxidation burning loss. Although there are many factors that can affect the comprehensive energy consumption per ton of steel in the rolling process, any factor may affect the energy consumption, but the most important factor is the heating temperature during the production and processing of the rolling process. Our analysis of the impact of comprehensive energy consumption per ton of steel rolling process must first be divided from the energy-saving links of the steel rolling process, which can be divided into rolling mills, steel rolling heating furnaces, and some auxiliary equipment, such as rolls, mechanical components, and other components. In addition, the level of energy consumption structure can be mainly divided into electricity consumption, fuel consumption, steam, energy recovery, and other related media energy consumption. These other media energy consumption include many parts, such as water, Oxygen, and nitrogen consumption in different degrees affect the comprehensive energy consumption per ton of steel to a certain extent.

The rolling speed of the rolling mill is affected by many aspects such as the rolled piece, product specification, material, etc. It is necessary to consider the frequency conversion speed regulation of the rolling mill to save energy. The range of the speed change is not large, and the rolling mill may be suitable for adjusting the rolling speed. Since the motor of the rolling mill operates in a constant voltage power supply mode, the energy consumption of the magnetic field of the motor remains unchanged, that is, the inductive current component remains unchanged. As the load decreases, the resistive current component decreases. This is the reason for the low power factor of the light load operation. When the load changes, the step-down constant power factor power supply method is adopted for the asynchronous motor, and the inductive current component is adjusted by adjusting the supply voltage, which can not only reduce the iron consumption but also reduce the copper consumption of the stator and rotor, so as to achieve the purpose of energy saving. As the load factor decreases, the operating efficiency of the motor is gradually improved, and the power factor increases.

Rolling mills can save energy by using inverters to adjust the speed of motors below the base frequency. The range of energy saving is related to the range of speed regulation. However, the range of adjustable speed of rolling mills is limited, and the energy-saving benefits are not obvious. From the perspective of energy-saving operation of steel rolling equipment, under the premise of meeting the same load power, according to the power factor of the minimum energy consumption optimization target, determine the best adjustment voltage to reduce the input active power of the motor to improve the operating efficiency of the rolling mill.