What happens to rivets of the D and DD series if they are not used within the specified time frame post heat treatment?

The rivets of the D and DD series are designed to maintain their mechanical properties within a specified time frame after heat treatment. If they are not used within this time frame, they may lose some of their effectiveness and strength due to changes in their material properties. Reheating these rivets within specific guidelines is necessary to restore their original properties, ensuring they regain the necessary strength and performance for their intended applications.

This need for reheating is critical as it helps to mitigate the risks associated with using rivets that may have degraded over time, which would impact structural integrity. Therefore, it is essential to follow manufacturers' recommendations regarding their handling and usage after processing, particularly concerning the time-sensitive nature of their usability.