1967 A.Wittemoser of Germany used magnetized iron balls instead of silica sand as molding materials and magnetic fields as binders. This is called magnetic mold casting. 197 1 year, Nagano, Japan invented the v method (vacuum casting method), and vacuum pumping was also used to fix the molding sand in EPC in many places. The use of binder-free dry sand process before 1980 must be approved by Full Mold Process, Inc., after which the patent will become invalid. Lost foam casting technology has developed rapidly in the world.
1990, GM established a new foundry with an annual output of 55,000 tons in Saturn, with three fully automatic EPC production lines.
199 1 year, Fiat Italy built the largest EPC workshop in Europe in Turin, with an annual output of10.5 million tons.
1993, BMW Germany built an EPC production line with an annual output of 200,000 aluminum alloy cylinder heads of various specifications.
In 200 1 year, the American general company SMCO built the most advanced and largest EPC workshop in the world.
domestic situation
In recent years, general contracting has developed rapidly in China, and the development results are also gratifying. Among them, Yunnan Kunming Hongjinlong Foundry Machinery Factory is relatively advanced in all aspects, and its products have been exported to neighboring countries such as Malaysia. In addition, universities such as Tsinghua University and Huazhong University of Science and Technology have also made valuable contributions to the development of EPC industry. The level of R&D and manufacturing equipment is mainly reflected in the following aspects:
(1) equipment development in white area: the preforming machine has been greatly improved and improved, and a lot of work has been done in the design of external structure, the improvement of foaming principle and the perfection of testing means. The performance of foaming machine has been greatly improved, which can basically meet the requirements of use. The molding machine has also been improved. With the improvement of automation level and its application in domestic mold manufacturing, the automation level of domestic mold manufacturing machine has also been obviously improved, and the production efficiency of mold manufacturing and the labor intensity of workers have been greatly improved and improved. However, the energy distribution of filling method needs to be further improved and perfected. Some work has also been done on the gluing machine, but the gluing level and ability of complex molds need to be improved. The mechanization level of coatings is low, the detection methods are not perfect, and the dirty, chaotic and poor situation of coatings department has not been obviously improved; Lack of paint recycling equipment and devices. At present, some domestic enterprises use stainless steel high-speed and low-speed mixing containers with Kawasaki manipulator to paint complex molds. However, due to their ignorance of the coating performance, they failed to design a reasonable and accurate fixture, and because of the unreasonable trajectory of the manipulator, when the manipulator invades the mold itself, the mold will expand and deform, the surface coating will be unevenly attached, and the cavity will be seriously exposed.
(2) Development of equipment in black area: The vibroflotation platform has been greatly improved and broken through, both the principle and control means of vibroflotation have been significantly improved, which is basically close to the design concept of foreign advanced equipment, but there is still a certain gap in details and control. The design and manufacturing capacity of sand cooler has also been greatly improved, and the sand cooling treatment requirements of molding line can be met without considering too many pits. The design and manufacturing capabilities of rain and sand, vibration transportation and other equipment have been significantly improved. The design and realization ability of automation has been greatly improved. The design and manufacturing level of automatic pouring machine is close to the advanced level abroad. The design concept of the whole molding line has changed greatly, and the wiring is more reasonable and the operation is more reliable.
(3) Development of process level: the process level is mainly reflected in the batch production process of engine cylinder block and cylinder head castings and the production process of difficult wear-resistant and heat-resistant castings.