Reasons for damage of refractory products lining in RH refining furnace

December 19, 2018

Reasons for damage of refractory products lining in RH refining furnace

The RH/RH-OB lining is used under vacuum sealing conditions, in which the ventilation pipe, nozzle, bottom and oxygen blowing port are all subjected to the maximum steel water circulation speed, so the initial erosion mode may be caused by the rupture of refractory near the hot surface. According to RH/RH-OB operating conditions, it is estimated that the lining will cause structural fracture or weakening in all processes.

Specifically it includes the following points:

(1) Thermal shock resistance damage between preheating and molten steel treatment due to rapid heating or cooling of the hot surface (the greater the temperature difference, the greater the damage)

(2) Due to changes in oxygen pressure and temperature, alternating cycle of Fe oxide causes damage to the lining.

(3) As the refractory bonding phase dissolves, it provides a channel for slag intrusion and causes the slag to infiltrate, resulting in erosion of the direct hot surface portion of the iron oxide enriched zone.

(4) Because the slag is saturated, the front edge of the hot surface erosion is close to the internal crack, so some damage may be the result of partial hot surface peeling loss. Usually such damage to the lining is discontinuous. Due to the relatively fast advancement of the erosion front and the stripping ability of the flowing molten steel, the peeling loss of the severely damaged part is larger.