Analysis On Struct And Force Of Complex Box Mold Via Lost Foam Casting

The box parts are the base of the machine or its elements, which generally havefeatures like complicated shapes, even wall thickness, clapboards and sockets, etc.Thus the lost foam casting process is very suitable for the parts and has been widelyused in the industrial productions. The quality of foam is the key to the success of lostfoam casting procedure, in addition that the mold’s producing process determines itsqualities. The key technologies of the production process include: the design of the lostfoam mold, the foam inflating molding of the foam peaberry and the demoldingprocess of the foam patterns.With the help of UG and ANSYS and the data collected from experiments, thisissue is to be discussed about in three aspects: the design of lost foam mold, theaffections of the foam inflation molding on the mold and the demolding process of thefoam pattern, which also offer the data support for the research into the deformationsof the complicated box parts in lost foam casting.The mold design was conducted with two methods: molding of fragment andmolding of integrity. Knowing from the practical applications, inappropriatefragmenting will lead to heavy deformation of foam patterns, which will greatly lessenthe rate of production as a result.The detection experiments determine the pressure of the mold as0.09MPa.According to the stress and the structure optimizing analysis, results can be concludedthat the foam inflating pressure has significant impact on the mold deformation, andincreasing the thickness of the pattern. Through the analysis of the fragmenting mold,it can be seen that the deformation and the strain of the mold cavity mainly happenedon the intersecting areas of the sides and the top surfaces which infers that thedeformation on bounding sides of the foam pattern pieces of the fragmenting moldingwas big. It agrees with the reality.The demolding forces of the foam patterns were analyzed, and it was found thatthe uneven gas pressure from the vents causes the outer tension of the foam patterns.By the optimizing process, the proper demolding force is decided as0.2MPa whichcould guarantee the complete high-qualified foam pattern when assuring successful drawing of patterns. The practical production was supported by the theory foundation.