What can occur if a fastener is not properly preloaded?

When a fastener is not properly preloaded, one significant consequence is the potential for joint loosening. Proper preload ensures that components are held tightly together, creating a stable joint that can withstand various forces and vibrations during operation. If the preload is insufficient, the fastener may not exert enough clamping force on the parts it holds together, leading to movement between these parts.

This movement can cause the fastener to loosen over time due to vibrations or thermal expansion and contraction, ultimately compromising the integrity of the assembly. A loose joint can lead to increased wear and damage, potential failure of the assembly, and safety hazards in critical applications. Therefore, achieving the correct preload is essential for maintaining joint stability and reliability.