Which defect is acceptable for a lifting chain?

The acceptance of surface rust as a defect for a lifting chain is based on the understanding that light surface rust does not significantly compromise the structural integrity or the functionality of the chain. While it is important to monitor the condition of lifting chains, surface rust typically indicates a cosmetic issue rather than a mechanical failure. Surface rust can often be removed through cleaning, and as long as the chain's diameter, strength, and operational capacity remain intact, it can still be considered safe for use.

In more critical cases, options such as twisted links, over 10% wear, and broken links present serious risks to safety and operational reliability. Twisted links can lead to improper load distribution and potential failure during lifting operations. A wear level exceeding 10% suggests significant degradation that can compromise the strength of the chain, and broken links render the chain unusable for lifting purposes and necessitate immediate replacement. Each of these defects indicates a deterioration that can lead to accidents or failures during lifting tasks, while surface rust does not pose the same immediate danger if managed properly.