Process characteristics:Yuchai's first thin-walled lightweight cylinder block made of vermicular iron in China VI is made of RuT400 instead of traditional HT250, and the strength of the cylinder body is increased by 60%. The minimum wall thickness is 4±0.75mm, and the product weight is reduced by 17%. Lightweight of products is realized. The iron sand coating process is used for production. In the whole production process, robot is used for coring, core assembling, dip-coating and core setting to improve the dimensional accuracy of thin-wall castings. MAGMA casting simulation analysis software is used to optimize the pouring system, and CAE is used to analyze the lightweight product structure.