Hot spots 1: reduce or eliminate the casting defects of lead alloy in EPC
The biggest problem of making lead alloy castings by EPC is the carbon slag inclusion. Foreign experts in EPC are also seeking solutions. Specific research directions include:
(1) Research on improving the fluidity of liquid metal;
(2) Skillfully improve the EPC coating, make it have better permeability, and make the carburization can be discharged from the coating;
(3) Although the slag inclusion can not be prevented by changing the bloom, it can be transferred to a relatively less important part;
(4) Mercurymarine company in the United States has taken the way of increasing pressure, so that the carbon increase can be quickly discharged under the pressure, and has also achieved good results in practical application.
Hot spot 2: foaming mold and white area mold making technology
Foundry enterprises attach great importance to the application of foundry software. At present, there are few application software about EPC, but there is a trend that Chinese enterprises popularize this kind of software.
Hot spot 3: EPC CAE and RP technology
CAE analysis and RP technology are more and more widely used, and European and American countries are also ahead in these fields. To sum up, it can be seen that if we want to produce similar water-cooled motor shell parts, the appearance is complex, the working environment is bad, with internal circulating water chamber and the annual demand is not small (no less than 2000 pieces per year). If RP technology is used for manufacturing, the cost is too high, which is disadvantageous to the development of the enterprise; ifis used, it needs to face the extremely complex outer contour. In order to be demoulded, multiple moving blocks must be set around the motor shell, and only the form of artificial “placing and spreading” can be used for core making. In the case of multiple moving blocks, it is difficult to place each moving block completely and correctly by manpower. When molding, the manual mold is used It is difficult to start the mold and easy to break the sand core. The workload of core repair in the later stage is large, the overall efficiency is too low, and the labor volume of workers is large. If the EPC process is adopted, the shell external mold can be manufactured conveniently, but there is no way to make the water cavity of the shell. Therefore, the feasibility of integrating EPC and sand casting is discussed. At present, there are few reports about the combination of the two processes, but from the research of papers and literatures, it is possible to combine EPC with other casting processes. If it is used well, the complex problems under the single casting process can be solved.