Although the baking-free ramming mass used in the iron hooks can meet the construction requirements of the small and medium-sized blast furnace, it can not make the iron hooks reach a long life.

1. The bulk density of the baking-free iron hook ramming material is small, the compressive strength is low, the erosion resistance is poor, and the anti-scouring ability is worse.

2. Frequent maintenance (some iron ditches are repaired almost every shift).

3. Labor intensity (frequent repairs are not only labor intensive, but also add a lot of danger).

4. Does not meet environmental protection requirements (asphalt, resin should be yellow smoke).