Preparation before the casting process
The working surface of the crystallizer is smooth, and the inner surface is polished with sandpaper when using ordinary molds. To ensure uniform water cooling, when casting multiple rods at the same time, the height of the base is consistent, and the mold and base are placed smoothly.
The casting launder and the distributing launder are fully dried.
A trough is an important tool for distributing liquid flow and slowing down the impact of liquid flow. Choose a suitable launder according to the ingot specifications before casting. If the funnel is too small, the night current cannot be supplied to the sides, resulting in defects such as cold partition and layering, which may lead to central cracks and side cracks in severe cases. If the funnel is too large, the temperature at the bottom of the funnel will be low, resulting in defects of light crystal and intermetallic compound. If the funnel is off-center, it will cause eccentricity cracks due to uneven flow. When using stainless steel or cast iron funnels, the outer surface should be polished and smooth. Heat it to 150-20°C before spraying. After spraying, it should not be hot and cold. All funnels must be fully preheated before use, and those using funnel racks should be adjusted in advance.
Adjust the melt temperature and control it at the upper and middle limits of the pouring temperature.
The temperature is well controlled during the casting process, generally in the middle limit.
Close each drop point.
Control the liquid level in the launder, flow plate, and crystallizer to avoid sudden high and low, and try to be as stable as possible.
Do a good job of lubrication. When using oil lubrication, the lubricating oil should be preheated in advance.
End of casting
The temperature before the end of the casting should not be too low, otherwise it is easy to produce slag in the gate.
Do not clean the surface scum on the launder and the launder before finishing, so as to prevent the scum from falling into the ingot.
After the flow is stopped, remove the flow plate in time, and carefully take out the automatic control funnel; for manual control funnels or annular funnels, the funnel can be taken out after the liquid level is out of the funnel. The gate is not slagging.
For the alloy to be tempered, stop the cooling water when the liquid is still 1/2-1/3 of the diameter, and drive down quickly, and stop when the ingot is 10-15mm from the crystallizer, and it can be lifted after the gate is completely solidified. For alloys that do not need to be tempered, the sooner they can be stopped when there is no water in the gate, the better, and the water should be stopped when the gate is cooled to room temperature. Stop when the small diameter ingot is 10-15mm away from the lower edge of the mold to prevent the ingot from pouring into the well.