(1) Refractory cement fineness: the finer the cement particles, the larger the specific surface area, the faster and more fully the hydration reaction, and the higher the early and late strength. National regulations: The specific surface area should be greater than 300 square meters per kilogram, otherwise it is unqualified.
(2) Setting time of refractory cement: In order to ensure sufficient time to complete various processes such as mixing, transportation, and molding during construction, the initial setting time of cement should not be too short; after construction, it is hoped that the cement can harden as soon as possible to produce strength , So the final setting time should not be too long. The initial setting time of refractory cement shall not be earlier than 45 minutes, and the final setting time shall not be later than 390 minutes.
(3) Volume stability of refractory cement: The uniformity of volume change of cement paste during the setting and hardening process is called the volume stability of cement. If the volume changes unevenly, that is, the volume stability is poor, it is prone to warping and cracking, which reduces the quality of the project or even accidents.
