Production preparation shall be carried out according to the established scheme. Since the injector hole core is made of hot core box coated sand, sand shooting and mold lifting are completed by mechanical automation, the set cold iron shall be positioned in the core box, and grooves to increase the adhesion of core sand shall be processed on the cold iron to prevent the cold iron from shifting and falling off during core making. Therefore, the cold iron is specially designed and processed to ensure the quality of sand core. After the completion of production preparation, the first test was conducted and the implementation of measures was checked (see Figure 1).
According to the developed scheme, 20 cylinder heads were tested for the first time. After cleaning, the surface quality of the castings was good and no air hole defects were found. One piece was randomly inspected for physical sectioning, and no shrinkage porosity and shrinkage defects were found (see Fig. 2). The casting quality fully met the product technical requirements.
Up to now, 400 cylinder heads have been produced according to the scheme, 8 waste products have been generated, and the yield is 95%.