Lifting chain is designed to elongate before fracturing as much as what percentage range?

• A. 25% to 35%
• B. 5% to 10%
• C. 15% to 30%
• D. 30% to 50%

Answer: (C)

Lifting chain is made to stretch a noticeable amount under load so that failure isn’t sudden; this ductility gives a warning before breaking and helps absorb shock. In practice, the elongation that lifting chains are designed to tolerate before fracturing sits in the mid-range, about 15% to 30%. This level balances strength with enough stretch to show visible deformation, without becoming so ductile that the chain’s load capacity is compromised.

Ranges with far less elongation would imply a much more brittle behavior and little warning before failure, while ranges much higher than 30% would indicate excessive deformability that isn’t typical for standard lifting chains. So the best-fit design target is approximately 15% to 30% elongation before fracture.