What is the maximum weight variance allowed for refractory in the bag?

The maximum weight variance allowed for refractory materials in a bag is ±2%. This standard is established to ensure consistency and reliability in the materials used for refractory installations. A variance of ±2% allows for a small margin of error in manufacturing and handling, which is practical given the nature of bulk materials. Adhering to this limit helps maintain the integrity of the refractory system, as variations beyond this range could lead to performance issues, such as inadequate thermal resistance or other properties essential for the refractory's effectiveness.

In contrast, stricter limits like no variance allowed could lead to challenges in procurement and usability, while allowing too much variance could jeopardize the performance and safety of the refractory installation. Thus, the ±2% tolerance strikes a balance that supports both quality control and operational viability.