Lost foam casting process is a very popular energy-saving and environmentally
friendly casting process, but because of the different shapes of a series of
castings such as machinery and equipment, how to control different types of lost
foam casting?
First, the dry sand modeling of the vanishing mold is the first step to add dry sand to the sand box. In order to ensure that the dry sand is filled in place, first add a certain thickness of bottom sand to the sand box and shake it tightly, then put it into the model cluster. Then, add a certain thickness of dry sand, bury the model cluster to one-third to one-half, and then perform appropriate vibration to promote the filling of the dry sand into the cavity of the model. Finally, the sand box is filled for vibration, and the vibration time should not be too long to ensure that the model does not appear to be damaged and deformed, and at the same time to ensure that the paint layer of the lost foam does not fall off and crack.
By checking the condition of the stamping waste, it is possible to determine whether the mold gap of the lost foam casting process is appropriate. If the gap is too large, the waste material will have rough undulated fracture surfaces and smaller shiny surfaces. The larger the gap, the larger the angle formed by the fracture surface and the bright surface. When punching, crimps and fractures will be formed, and even a thin edge protrusion will appear. Conversely, if the gap is too small, the waste material will have a small angle fracture surface and a large shiny surface.
Lost foam casting is used mostly for automotive applications such as automatic parts casting.
Hot cracking of Lost Foam Cast Iron is a common casting defect, so what can we do to avoid preventing this phenomenon?
Lost foam cast iron parts are mainly due to the fact that during the casting process, part of the pyrolysis products are discharged through the coating, and another part of the pyrolysis products gradually moves up with the upward filling of the molten iron. The type of molten iron has serious turbulence, and the amount of pyrolysis products involved in the molten iron increases, and there is no riser at the top. These molten irons that are contaminated by the pyrolysis products cannot be excluded from the riser. As the carbon content increases, the linear shrinkage coefficient of cast iron increases, and the internal stress gradually increases. After the casting, the vacuum degree is kept high, and the strength of the molding sand is strong, which seriously hinders the shrinkage of the casting. Under the action of the ribs, cracks occur on the plane of the continuous plate.
First, the dry sand modeling of the vanishing mold is the first step to add dry sand to the sand box. In order to ensure that the dry sand is filled in place, first add a certain thickness of bottom sand to the sand box and shake it tightly, then put it into the model cluster. Then, add a certain thickness of dry sand, bury the model cluster to one-third to one-half, and then perform appropriate vibration to promote the filling of the dry sand into the cavity of the model. Finally, the sand box is filled for vibration, and the vibration time should not be too long to ensure that the model does not appear to be damaged and deformed, and at the same time to ensure that the paint layer of the lost foam does not fall off and crack.
By checking the condition of the stamping waste, it is possible to determine whether the mold gap of the lost foam casting process is appropriate. If the gap is too large, the waste material will have rough undulated fracture surfaces and smaller shiny surfaces. The larger the gap, the larger the angle formed by the fracture surface and the bright surface. When punching, crimps and fractures will be formed, and even a thin edge protrusion will appear. Conversely, if the gap is too small, the waste material will have a small angle fracture surface and a large shiny surface.
Lost foam casting is used mostly for automotive applications such as automatic parts casting.
Hot cracking of Lost Foam Cast Iron is a common casting defect, so what can we do to avoid preventing this phenomenon?
Lost foam cast iron parts are mainly due to the fact that during the casting process, part of the pyrolysis products are discharged through the coating, and another part of the pyrolysis products gradually moves up with the upward filling of the molten iron. The type of molten iron has serious turbulence, and the amount of pyrolysis products involved in the molten iron increases, and there is no riser at the top. These molten irons that are contaminated by the pyrolysis products cannot be excluded from the riser. As the carbon content increases, the linear shrinkage coefficient of cast iron increases, and the internal stress gradually increases. After the casting, the vacuum degree is kept high, and the strength of the molding sand is strong, which seriously hinders the shrinkage of the casting. Under the action of the ribs, cracks occur on the plane of the continuous plate.
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