Copper Melting and Holding

Two types of lining materials for copper melting: 

SIL-RAM ® 120CU is a fused silica-based acid lining material with excellent volume stability and resistance to molten copper penetration.It is recommended as the lining material to large coreless induction furnace for melting brass and propeller bronze;

ALU-RAM ® CU series are alumina-based materials with silicon carbide, fused silica or magnesium oxide added.

The addition of silicon carbide improves the material's resistance to slag and corrosion.

The addition of magnesium oxide improves the density and erosion resistance;

This series include ALU-RAM ® 122CU, ALU-RAM ® 125CU, ALU-RAM ® 130CU, ALU-RAM ® 135CU etc.

Main points of demolding during sintering process:

1. For large furnaces, use smeltable molds as the first choice. The lining needs to be sintered to the specified temperature before pulling out the mold, and a long-time heat preservation is necessary. If the process control is not strict, the lining will be damaged easily;
2. The penetration of copper is strong, so the density of the lining during installing must be ensured, and the paper or tape for wrapping the mold is easily be broken during the installation process, so avoid the scraps falling into the lining;
3. the large furnace must use the split mold, and use gas for sintering as much as possible, if use the electric power for sintering, the joint of the mold is easy to have arc discharge, that will damage the mold, and it is not conducive to demolding later;
4. It is also a key link of the charging and melting process after demolding. The surface strength of the lining after the first stage sintering is not very high. If the charging material is too large, the lining is easily damaged, especially in the upper part when the material is sinking, the worst result is to reject the lining.