China has developed and introduced advanced and low and no oxidation heating furnaces, such as vacuum furnace, protective atmosphere furnace, controlled atmosphere furnace, ion nitriding furnace and so on. The proportion is less than 20%. And, these advanced heating equipment because of the quality of management and operator is not high, did not give full play to the role of the equipment. Therefore, it is necessary to modify the technology of heat treatment heating furnace.
First, we should promote new technology, develop new technology and materials, and train staff and workers to improve the quality of employees
The renewal of heat treatment process equipment is also very heavy. In promoting the adoption of new vacuum heating equipment and protective atmosphere and controlled atmosphere heating equipment, it is also important to transform the traditional active heating equipment. Practical options and technical reform measures are selected and promoted to create considerable wealth for enterprises and countries.
Two. Natural gas is the best source of energy
The rational choice of energy is the first problem to be considered in the energy saving of heat treatment equipment. Heat treatment energy can be divided into two major categories: electric energy and fuel. Electricity or fuel and fuel depend on production cost, energy supply condition, operation and control's difficulty and reliability, the characteristics of heat treatment process and ecological environment.
The advantages of electric heating are clean, the temperature is easy to be controlled, the auxiliary facilities are few, and the operation is simple. The heat utilization rate of 70%~~80% can be obtained theoretically by using resistance furnace heating, but electricity is the two energy. Considering the efficiency of power generation, the comprehensive heat utilization rate of resistance furnace is not more than 30%. The price of electricity is high and the cost of production is high. Due to the development of science and technology and the increase of the proportion of hydropower and nuclear power, the price of electricity in the international market has a relatively decreasing trend. Therefore, the current international trend is to increase the proportion of electric energy gradually.
Fuel than electricity is cheap, but the combustion process is more complex, at the same time with the fuel ratio power will cause more pollution. However, with the progress of control technology, it is possible to achieve accurate control of the temperature of gas generation and liquid fuel furnace.
Natural gas is the primary energy, heat treatment furnace, in addition to the direct heat of combustion efficiency could be obtained at least 30%, flue gas waste can also be used to preheat combustion, heating, air heating and tempering furnace cleaning liquid and quenching oil and other living purposes, the absolute heat utilization rate can reach more than 80%. At present, the heat treatment fuel furnace of the advanced industrial countries occupies a considerable proportion.
According to the survey, the proportion of heat treatment fuel stove in Western Europe accounted for 20%~30%, and the United States accounted for 25.5%, while the Japanese fuel stove mainly used heavy oil, kerosene, liquefied petroleum gas and city gas accounted for 61.4%.
In the past 10 years, China's natural resource exploration breakthrough. It will create very convenient gas use conditions for the heat treatment industry. The vast enterprises should see the favorable prospects for the change of heat treatment energy, and take full consideration and use of the technological transformation of heat treatment production and the renewal of equipment.
Three. The energy saving effect of circular furnace is obvious
The enterprise usually selects the furnace form from the process requirements, the shape and size of the workpiece and the production batch. From the point of view of heat treatment energy utilization, the efficiency, sealing and furnace shape of the heater should be considered. When the pieces are large and the variety is single, the continuous furnace should be adopted. Under the same furnace chamber volume, the circular (column) furnace has a better energy saving effect than the square furnace.