The Surface Pressure Control Based On Low Pressure Casting

With the rapid development of China's automobile industry, Up to now China's auto output and sales volume has reached first in the world. Energy consumption of the car more and more aroused great attention. With the lightweight, energy-saving & environmental protection requirements continue to increase, Aluminum alloy castings in the automotive industry is increasing the proportion, but also boost the special aluminum alloy casting forming process of rapid development. Low-pressure casting process as forming of one casting has also been rapidly gaining popularity and promotion. Compared with the traditional gravity casting, low pressure casting process has a very special advantage. You can create a better quality than the traditional casting process. Cooling system can be used with the mold. The mold temperature through the control of casting solidification can be achieved. And casting and casting directly from the bottom feeding, the riser isn't used, the casting process produced a very high rate (generally 90% or more). As the three KG pressure of casting is filling the mold cavity under pressure, so the available castings more compact structure, good dimensional accuracy and surface finish can also be used to create a sand core complex structure of the cylinder block, cylinder head type castings. Low-pressure casting process to produce castings with good mechanical properties, has attracted wide attention foundry workers, the majority of car alloy wheels are taking low-pressure casting process. Low-pressure casting process is widely used at present in Japan in recent years, along with the rapid development of China's automobile industry. The foreign manufacturer of low pressure equipment is also very concerned about China as "the market of big cake", the international technical cooperation and exchange more closely. Therefore, China's low-pressure casting technology has been greatly improvedFirst, the paper with low-pressure casting process problems in a systematic analysis to determine the impact of the quality of casting molding and casting a critical parameter, from the control point of view to explain the casting molding and solidification process.Secondly, the design of the gas pressure control programs, and low pressure systems analysis, summarized the factors that affect the surface pressure curve to determine the fuzzy PID control scheme.Finally, the production company where I practice, continue to optimize the design. So, confirming the use of PLC as a means of control, combined with the theory of fuzzy PID control system for low liquid pressure studies, is a certain amount of theoretical and practical significance.