The PPR aluminum-plastic pipe is composed of 5 layers, and the middle layer is made of aluminum sheet. The molding process is relatively complicated, and it is different from other pipes, and there is no sizing sleeve and vacuum water tank. Therefore, the welding quality of the aluminum strip is the key element of the pipe forming. Through the investigation, it was found that there were still major defects in the five processes, which affected the stability of production, resulting in low indicators of PPR aluminum-plastic pipes;

The workshop conducted a summary analysis of customer complaints in 2021, and learned that PPR aluminum-plastic pipes accounted for 57.14% of the total complaint rate in the workshop.

And in the first half of 2022, the defective rate is as high as 8.34%, which has great quality hidden dangers and cost waste, so this topic is selected for improvement.

Reason Analysis
Aiming at the terminal factors obtained by the team members through analysis, a factor confirmation schedule was formulated. Confirm that the main factors are distributed in three aspects: personnel factor, equipment factor and material factor, and implement countermeasures after updating the target value

 Implementation of countermeasures
Solve the phenomenon of insufficient operator capacity (personnel factor)
Solve the phenomenon of insufficient ability of debuggers (human factors)
Installation of pipe anomaly automatic detection device (equipment factor)
Standardized management and control of aluminum strip storage methods and storage cycles (equipment factors)
Reworked forming wheel platform (equipment factor)
Improvement of the flow channel of the external plastic mold (equipment factor)
Solve the phenomenon of penetration of the external plastic co-extrusion line (equipment factor)
Aluminum strip forming parts implement standard maintenance control (equipment factor)
Solve the unqualified phenomenon of aluminum strip entering the factory performance index (material factor)
Solve the phenomenon of poor sticking effect of hot melt adhesive (material factor)
Solve the phenomenon of inner rubber leakage (material factor)

Results summary
This time, through the joint efforts of the workshop team and the research institute, the persistent problem of high complaint rate and high defective rate of PPR aluminum-plastic pipes has been completely solved. The follow-up workshop will continue to take effective consolidation measures to ensure that PPR after this improvement Various indicators of aluminum-plastic pipes continue to show a downward trend and no longer rebound:
1. Keep a close eye on the indicators of PPR aluminum-plastic pipes and make them announced every day;
2. Continuous improvement and expansion of the commissioning ability of the debugger;
3. All molding parts are well maintained according to the standard, and the records are output.