Lost foam casting process is a casting process in which EPS white mold models similar to the size and shape of castings are bonded and combined into mold clusters, coated with refractory materials, dried and buried in ceramsite sand, vibrated and compacted under negative pressure, poured metal liquid under negative pressure to gasify the model, the liquid metal occupies the model position, solidified and cooled to form castings.

In addition to giving full play to the common advantages of lost foam casting process, such as good casting quality, low cost, small cleaning workload, improving working environment, energy conservation and environmental protection, improving surface quality, ensuring casting wall thickness accuracy, dense organization, improving mechanical properties and optimizing casting process, it is an obvious advantageous process suitable for the structural characteristics of vacuum rim products. At the same time, due to the characteristics of lost foam casting process, the final mold of vacuum rim air hole system and valve hole is designed to save machining process and equipment investment, which can significantly reduce the machining cost; The bolt mounting hole is cast near the final shape to reduce the machining allowance and significantly improve the machining efficiency.

Aiming at the casting structure of small modulus and large profile thin-walled parts of vacuum rim, the deficiency of lost foam casting process is EPS white mold deformation, especially the white mold deformation on one side of wheel flange. This problem is considered to bond triangular or cross shaped glass fiber strips (or bamboo strips) at the large opening on the side of wheel flange before painting lost foam casting coating Reinforced anti deformation measures to solve.