Process characteristics：in-line, six-cylinder structure. The self-hardening sand on-line production process is adopted for on-line core assembling, core setting and pouring. Castings are poured by horizontal pouring process, and water is fed into the multi-layer ingate, which effectively improves the uniformity of the temperature field of molten iron on the cover box surface. In the production process, the defect rate of pores and sand holes in castings is low, and the quality is stable and controllable.