Development of internal pressure monitoring system for control of explosive spalling in refractory castables

During the initial heating of hydraulically bonded castable refractories, dehydration of cement phases causes build-up of high levels of internal steam pressure. If this pressure exceeds material strength, explosive spalling results. A probe capable of measuring internal steam pressures"in-situ" has been developed and tested. Correlation of cement calorimetry and pressure data suggests that castable heating schedules can be modified to reduce explosive spalling.