What design feature helps accommodate thermal expansion in mechanical assemblies?

What design feature helps accommodate thermal expansion in mechanical assemblies?

• A. Increased rigidity.
• B. Expansion joints.
• C. Rigid mounting only.
• D. Increased lubrication points.

Answer: (B)

When temperatures change, metal parts grow or shrink, so a design must tolerate some movement to avoid stress. Expansion joints provide that tolerance by letting connected parts slide, bend, or extend relative to each other while still staying connected. They come in forms like flexible bellows, sliding joints, or flexible couplings that absorb the extra length as temperatures rise. Increased rigidity would resist any change and push the expansion into stress, risking deformation or misalignment. A rigid mounting fixes parts in place and offers no way to accommodate length change. More lubrication helps reduce friction but does not provide a path for the parts to move to accommodate expansion. Expansion joints are the feature designed to handle thermal expansion.

When temperatures change, metal parts grow or shrink, so a design must tolerate some movement to avoid stress. Expansion joints provide that tolerance by letting connected parts slide, bend, or extend relative to each other while still staying connected. They come in forms like flexible bellows, sliding joints, or flexible couplings that absorb the extra length as temperatures rise. Increased rigidity would resist any change and push the expansion into stress, risking deformation or misalignment. A rigid mounting fixes parts in place and offers no way to accommodate length change. More lubrication helps reduce friction but does not provide a path for the parts to move to accommodate expansion. Expansion joints are the feature designed to handle thermal expansion.