Factors Affecting Converter Service life
1.Slag composition
For every 1% increase of iron oxide content in slag, converter life decreases 18~20 times. The higher MgO content in slag, the lower corrosion to furnace ling. The larger slag alkalinity, the lower corrosion to furnace lining.
Tapping temperature
The higher tapping temperature, the shorter converter life. The tapping temperature is usually above 1600℃, for every increases of 50℃, the service life decreases 50%.
2.Smelting time
The longer the smelting time, i.e., the longer blowing smelting time can accelerate the corrosion of converter lining. The service life of converter is inversely proportional to smelting time.
3.Batch operation
When one batch of smelting is finished, converter temperature quickly drops, when another smelting begins, temperature climbs soon, which can lead to strong thermal shock and thermal stress, the corrosion to lining is accelerated, there may have crack or stripping in lining, the service life of lining is significantly decreased.
4.Material charging
When charging iron liquid and furnace burden, factors such as furnace tilts, material impact and iron liquid washing, all will cause the discontinuous damage of furnace lining. All these damages should be timely patched, or the life of converter will be greatly decreased.
5.Smelting tempo and refractories selection
If production load is heavy, smelting tempo is rapid, refractories should have strong corrosion resistance, so low carbon containing magnesia carbon bricks should be adopted. On the contrary, if smelting tempo is slow, smelting interval is long, high carbon containing magnesia carbon bricks should be adopted.
6.Steel species
Caron steel smelting as low smelting temperature and constant slag ingredient, so its service life is much longer, if desulfurization and other treatment are carried out, the service life will decrease greatly. Top bottom combined blowing technique also greatly reduces the service life of converter lining.
7.Operation condition
Good operation condition is the basis of long service life. Generally, the operation condition should not be changed, it is decided by steel species, process craft and operator skills.
8.Maintenance
Maintenance is another factor affecting converter service life. Proper maintenance can increase lining service life for several times. The main maintenance methods of converter lining are: hot self flowing material patching, gunning mix patching and slag splashing protection.
