Guidance on Proof Test or Break Test of Chain Sling

Chain Sling is an assembly of lifting components made in a configuration of one or more chain legs for attaching loads to the hook of a crane or other lifting appliance.

The alloy chain sling must be proof-tested by the manufacturer when new, repaired or reconditioned.  Proof testing is a non-destructive tension test to verify construction and workmanship.

Conducting a break test on a chain sling is generally not recommended and is not a common practice in the industry. Break tests are typically reserved for destructive testing of materials or products to determine their ultimate strength and are not suitable for routine testing of equipment like chain slings.

Here's why break tests on chain slings are generally discouraged:

• Destructive Nature: A break test involves subjecting the chain sling to loads until it fails or breaks. This process permanently damages the sling and renders it unfit for further use. Chain slings are expensive and essential lifting equipment, and intentionally destroying them is costly and impractical.
• Safety Concerns: Break tests can be dangerous due to the unpredictable and sudden failure of the sling. This can pose risks to personnel involved in conducting the test and anyone in the vicinity. Safety precautions for break tests are more challenging to implement compared to proof tests.
• Alternative Testing Methods: Proof tests are the standard method for evaluating the safety and fitness of chain slings. A proof test involves applying a controlled, incremental load to the sling up to a specified percentage of its rated safe working load (SWL) to verify its condition and performance without causing damage. This method allows for the sling to be safely returned to service if it passes the test.
• Regulatory and Industry Standards: Most industry standards and regulations do not recommend or require break tests for chain slings. They typically specify proof testing procedures and criteria for evaluating the integrity of lifting equipment.
• Cost and Practicality: Repeatedly subjecting chain slings to break tests would be costly and impractical, as it would result in the constant replacement of slings. Proof tests are a more cost-effective and sustainable way to ensure safety.
  
  

If you have concerns about the condition or safety of a chain sling, it is advisable to follow established inspection and maintenance procedures, including periodic proof testing as per industry standards and manufacturer guidelines. If a chain sling has been subjected to unusual stress, damage, or an accident, it should be inspected and assessed by a qualified professional to determine its suitability for continued use.