The slag holes are mainly distributed around 2 and 5 turns, accounting for 22.7%; the defect area is large and in pieces. After dissecting the gating system, it was found that many fiber filters used for hot metal filtration were deformed and broken (Fig. 1), which had no effect...
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Improvement of cold shut defect in crankshaft casting of large engine
The generation of cold shut is directly affected by the temperature of molten iron. At a certain temperature, the design of gating system is the key to the filling capacity of molten iron. Through simulation and analysis, it is found that the original runner design of gating system is...

Solution of air gap defect in crankshaft casting of large engine
The air-conditioner of the defective product is mainly located at the highest point of the mold, i.e. 2 and 5 turns (as shown in Fig. 1, the dark position). Through the simulation and analysis, it is found that the filling speed of the mold becomes slower, the filling ability...

Formation of defects in crankshaft casting of large engine
Air conditioner The cold air gap is the gap that penetrates or does not penetrate the casting, and the edge is rounded, which is caused by the poor fusion of the filling metal streams. According to the analysis of the causes of the cold air gap in conventional castings,...

Improvement of sand hole defect in crankshaft casting of large engine
In the molding process of sand coated iron mold, sand collapse and empty shell are the important reasons for sand hole defects. Through a large number of data collection and confirmation, the empty shell is mainly concentrated in the second and fifth connecting rod neck, which is easy to...

Formation mechanism and prevention and control of main defects in nodular cast iron intake cylinder casting
(1) The elements with high content of C, O, Al, Si and some other alloy elements are found in the defect position of the inlet cylinder casting surface detected by Mt. The results show that the main defect is the primary oxide slag inclusion formed by the aggregation of...

Application of ductile iron gating system in prevention and control of surface slag inclusion defects
The whole process from molten iron smelting to casting completion is a complex and irreversible process. In the process of high temperature smelting and pouring, it is impossible to ensure that the oxide slag is completely removed and does not enter the mold cavity. Theoretically, in order to effectively...

Morphology and composition analysis of linear defects on inlet cylinder surface
The main characteristics of the magnetic traces of linear defects detected by MT are mainly linear aggregated magnetic traces with large length width ratio. In ASME standard, the linear defects are defined as the display with the aspect ratio greater than 3. The defect indication position of the intake...

Morphology and composition analysis of point defects on inlet cylinder surface
The main features of magnetic traces of point defects detected by MT. The magnetic traces are scattered and isolated small spots, stripes and cloud like discontinuous distribution. In the ASME standard, the size of the recorded defect is defined as the indication of more than 1.5mm. In normal production,...

Slag inclusion defect on casting surface of nodular cast iron intake cylinder
The surface slag inclusion defect is the most common and the most difficult to avoid on the surface of gas turbine intake cylinder casting surface, mainly concentrated in the upper plane of pouring position, the upper surface of air port surface and the dead angle position of casting filling...
