Chain Break
Location: Liaoning
Time of occurrence: July 29, 2018
Client: Agent
Problem Description:
After the equipment (new machine) was transported for 400 kilometers, the chain was broken after each copy was glued at the customer.

Temporary Measures:
Provide a qualified chain for on-site repair and replacement by the dealer
Full inspection of all inventory chains in the warehouse
Perform fatigue test on the chain installed and used on the production line, and continue to operate

Identify And Verify The Root Cause:
1. After confirmation, the chain used is provided by Hanfa Hardware (the only supplier)
2. The site is measured and confirmed by the dealer, and the sprocket and gear are installed without tilt
3. 700 chains in the warehouse were fully inspected, and 52 chains were found to have cracks in the connecting pieces, and the defect rate was 7.4%
4. On August 2nd, the supplier delivered 400 pieces and randomly inspected 50 pieces. It was found that 2 pieces of connecting pieces were cracked, and the defect rate was 4%.
Chain break is confirmed as chain material quality problem

Corrective Action:
1. Re-search for new chain suppliers and conduct corresponding new supplier audits
2. Increase chain inspection efforts and increase sample size for sampling inspection

Corrective Action Effect Verification:
1. After replacing the new chain supplier, the incoming inspection did not find any chain cracks
For equipment shipped after 2.8 months, no abnormal feedback of chain breakage was received

Preventive Measures:
Increase chain incoming material inspection specifications, clarify inspection items and key points