In order to ensure the smooth filling of the ductile iron casting machine and reduce the defects such as iron beans and oxidation inclusions caused by splashing, the machine body adopts two independent casting systems, and the bottom gate is introduced from both sides of the cylinder surface. When machining the cylinder head bolt holes, it was found that some bolt holes had different shrinkage holes and shrinkage defects, resulting in a large number of bolt holes in the cylinder head of the body, and the most serious body inserts were up to 25. The data shows that the cylinder head bolt holes with casting defects are mostly distributed on both sides of the 280 body (ie, the ingate accessory), while the cylinder head bolt holes near the air cavity have relatively few casting defects. The paste-like solidification characteristics of ductile iron determine its large liquid shrinkage. For shrinkage, shrinkage and shrinkage are easy to occur, and the amount of liquid shrinkage increases with the increase of casting temperature. During the solidification process, as the temperature decreases, the molten iron first undergoes liquid shrinkage. When the temperature is lowered to the liquidus, the precipitation of graphite begins with volume expansion (graphitization expansion) until the molten iron is completely solidified and the graphite is precipitated. When the molten iron is graphitized and expanded, the expansion pressure is related to the modulus of the casting and the quality of the molten iron. That is, the mold modulus increases, the spheroidization is better, the graphite shape is better, and the quantity is increased, the expansion pressure is greater. Reasonable use of the graphitized expansion characteristics of ductile iron is conducive to obtaining a well-organized casting. On the contrary, the insufficient or unreasonable use of graphitization expansion will lead to the shrinkage of the castings and the formation of shrinkage cavities and shrinkage. Suzhou Newstar Hardware Co.,Ltd is China manufacture and supplier of Socket Spanner Set, Socket Spanners and we are specialized in T Bar Socket Spanner, Spanner Socket Tool Set and other kinds of Tool Kits. We have more than 400 different modules of tool kits which you could choose from. And also we have strong ability of OEM and ODM services, could make different modules based on customer design, and customized logo, colors, etc. Welcome your visit. Socket Spanner Set,Socket Spanners,T Bar Socket Spanner Set,Spanner Socket Tool SUZHOU NEWSTAR HARDWARE CO.,LTD. , https://www.hardwarenewstar.com