1.Higher refractoriness than ordinary paper runners, for cast iron and steel;
2.Appropriately wall thick, tight sealing;
3.Provide complex shapes and extra long fittings;
4.Accurate shape size and smooth inner and outer surfaces;
1.Embedding in the sand must be enriched.
2.When pouring molten iron, according to the basic specification for pouring, the molten iron must be sealed at the pouring port and no air can enter.