Metal Forging Energy Saving Technology Research
1 Metal Forging Energy Consumption and Pollution Status
1.1 High energy consumption
In the metal forging industry, the efficiency of energy use is limited by the work experience of practitioners, the thermal efficiency of materials, and the level of facilities. Energy waste is a serious phenomenon. The forging process mainly includes feeding, heating, forging, processing, and heat treatment. The heating process is the most energy-intensive process. According to statistics, the fuel consumption of the heating process accounts for about 75% of the entire process. At present, China's metal forging furnace technology is relatively backward, the average energy consumption per kilogram of forgings is about 20,000 kJ, and the average thermal efficiency is less than 5%.
1.2 Serious forging pollution
The pollution generated during the forging process mainly includes pollution gas emissions, industrial waste discharge, and noise pollution. During the forging process, the combustion of materials generates a large amount of polluting gases. Some of the gases are discharged into the atmosphere without treatment, and carbon monoxide and sulphide pollution are the most serious. At the same time, carbon dioxide emissions will also exacerbate the greenhouse effect. The wastes discharged from metal forging mainly include waste oil, waste liquid and waste slag, including both coal residues after burning, fuel waste, and metal scraps and used machine lubricating oil. Some of the wastes have poor degradability and are polluted. Without adequate treatment, it will have a bad influence on the natural environment. Metal forging requires the use of many large-scale machinery. When the machine is in operation, it generates a lot of noise and affects the lives of surrounding residents.
2 Application of Energy Saving Technology in Metal Forging
At present, the application of energy-saving technologies and energy-saving technologies in metal forging mainly includes the following three aspects.
2.1 Energy Saving Process and Equipment
(1) Cold extrusion and cold forging: In the traditional metal forging process, the energy consumed by the heating and heat treatment process exceeds 75% of the entire process flow. In order to effectively save energy consumption, the cold forging process has emerged. The cold forging process is a forming process at a material recrystallization temperature, and forging is performed below the recovery temperature. At present, in many industries, such as automotive parts and some electronic equipment, cold forging technology has been promoted and applied. On the basis of further improvement of forging quality, the energy saving effect is very significant. See the following figure: Figure 1 Cold-forged lamp housing radiator (2) Isothermal forging: Isothermal forging is a plastic processing process in which a mold and a blank are heated to a forging temperature and then deformed at a low strain rate at this temperature. The deformation of isothermal forgings in the final forming stage is relatively slow, which is conducive to grasping the degree of deformation, so as to obtain a forging accuracy that is close to no excess, and significantly reduces the consumption of metal materials. (3) Reform of electro-hydraulic hammer: With the advancement of science and technology, the energy efficiency of the electro-hydraulic hammer has been greatly improved, and its energy efficiency has been increased to 15%-20%. At the same time, its driving power has been changed from boiler steam to electric drive. The dust pollution brought by the boiler's coal combustion has been reduced, and the environmental benefits have been improved. (4) Modification of the cooling water circulation system: When forging equipment, a large amount of cooling water is required in order to maintain the normal operation of the system. In particular, the IF furnace and the heat treatment furnace consume the most. Through the transformation of the cooling water circulation system, a regulating pool and a submersible pump are set up, and the cooling water in the forging process is cycled and used repeatedly, which can significantly reduce the waste of water resources.
2.2 Energy Saving of Process Flow
(1) Energy-saving of production lines: The energy-saving of production lines mainly includes the following three aspects: First, the high-temperature exhaust gas is recycled, and the heat in the exhaust gas of the heating furnace is used in multiple stages in accordance with the temperature gradient. For example, the heating mold and the thermal insulation equipment can be used during isothermal forging. Heating furnace exhaust gas to achieve; second is the use of continuous Casting
and forging process, in the same set of molds, the first casting, casting immediately after completion of forging, so as to avoid the re-heating of the casting after cooling caused by energy waste; After the waste heat is used in the heat treatment process, the heating furnace is placed after the forging process, and the heat stored by the forging is fully utilized through such means as residual heat quenching, residual heat isothermal, and residual heat normalizing. (2) Energy saving in the forging process: scientific regulation of forging strength and forging sequence can effectively achieve energy saving. In the specific operation process, energy-saving process data can be inserted into the computer-aided process design system, and through system evaluation, the process flow with the lowest energy consumption and cost can be found to achieve energy-saving production. as shown in picture 2
. 2.3 production scheduling energy
Production scheduling is the process of rationally deploying workpieces that are waiting to be processed, as well as production lines and machines, and arranging the order in which the workpieces are produced by the machine. Reasonable allocation of production system resources can optimize production indicators, increase work efficiency, and reduce resource waste. In metal forging, the production scheduling can be optimized mainly from three aspects. The first one is forging furnace. Mainly through the rational distribution of forging materials, increase the use of heating furnace; Second, forgings out of the furnace. Mainly by reducing the holding time, reducing the number of open furnace and other methods, do a good job forgings forging and forgings between the forging of the connection; three forgings forging. Take full account of the forging steps and the materials and time required for each stage to minimize waiting time for forging equipment. See below:
Metal forging is the cornerstone of heavy industry development, and the current metal forging industry still has a lot of room for improvement. This paper analyzes the current status of metal forging and focuses on the application of energy-saving technologies. It hopes to help promote the popularization of energy-saving optimization technologies in various industrial production industries.