(1) It can perform annealing, quenching, tempering and other heat treatments like the electric heating vacuum furnace.
(2) Due to the use of radiant tube burners, fuel costs can be reduced by 2/3 compared with the electric heating type.
(3) CO2 emissions can be reduced by 40% compared with the electric heating type.
(4) The regenerative radiant tube burner has been improved and the radiant tube flange has been water-cooled, thus achieving vacuum sealing of large radiant tube flanges.
The structural principle of the gas-fired vacuum model furnace is shown in Figure 6 [7].
The specifications of the gas-fired vacuum model furnace are as follows:
Temperature in the furnace is usually 1050℃
Vacuum degree reached 0.7Pa (absolute pressure)
Effective dimensions in the furnace 600mm′600mm′900mm
Maximum processing capacity 400kg/furnace
Furnace structure Water-cooled double-wall structure
Attached equipment Pirani vacuum gauge, oil rotary pump, mechanical booster vacuum pump
Product cooling device N2 cleaning, pressure 140kPa
Burners 101.6mm regenerative radiant tube burners 41kW/2 sets
Radiant tubes 101.6mm W-type x 2 sets
The gas-fired vacuum furnace is a high-efficiency (thermal efficiency can reach 80%), high-quality, energy-saving (more than 60%), material-saving and environmentally friendly (developed and developed by European and American countries in the late 1980s under the impact of the oil crisis and the promotion of high-temperature air combustion technology (HTACT) NOx, CO2 and noise are greatly reduced) of the new type of heat treatment equipment. Due to its advanced technology and huge potential for energy saving and material saving, its technical and economic benefits are remarkable. At the same time, this technology has excellent environmental protection characteristics, conforms to the green heat treatment and sustainable development strategy, and therefore has broad development prospects.
During the "15th Five-Year Plan" period, my country vigorously developed natural gas energy. my country's natural gas energy will increase from 23.8 billion m3 in 1999 to about 64.5 billion m3. With the implementation of the Western Development and West-East Gas Transmission Project, the large-scale use of natural gas energy in Shanghai after 2003 will be realized. The use of clean, high calorific value natural gas energy and high-temperature air combustion technology to develop heat treatment equipment and technology is an urgent research, development and promotion and application topic for heat treatment scientific and technological workers across the country. The introduction of the research, development and application of gas-fired vacuum furnace technology is only a part of this research and development project. People gradually realize that it is imperative to research and develop high-temperature greenhouse gas combustion technology natural gas gas heat treatment technology equipment, which has great potential for energy saving, environmental protection and economic benefits, and has a very broad development space.
