API 936 Refractory Personnel Certification Practice Exam 2025 – All-in-One Resource to Ensure Exam Success!

The minimum cure time required for freshly placed air-setting and cement-bonded refractories is 24 hours. This timeframe is crucial to ensure that the bonding agents within the refractory material adequately set and cure, developing the necessary strength and durability for the applications they are intended for. During the curing process, moisture is essential to promote the hydration reaction of the cement and allow for proper chemical bonding, which contributes to the overall integrity and performance of the refractory.

Curing for less than 24 hours can lead to incomplete hydration, resulting in weak points within the material, potentially leading to early failures or reduced thermal stability. Therefore, adhering to the recommended minimum cure time is fundamental in refractory applications to achieve the desired properties and ensure safety and functionality in high-temperature environments.