How soon must refractory materials be applied after initial qualification?

Refractory materials must be applied within a specific time frame after their initial qualification to ensure optimal performance and adherence to safety standards. In this instance, the requirement is to apply the materials within four months of qualification. This time limit is established to maintain the integrity and effectiveness of the materials, as they may degrade or lose their properties if stored or delayed beyond this period. After four months, the physical and chemical characteristics of the refractory materials may not be reliable for achieving the intended results in a high-temperature environment. Hence, the requirement emphasizes the importance of timely application to preserve the quality and functionality of the materials used in refractories.