Appearance inspection:
The appearance of aluminum-plastic composite covers should be flat, smooth, with uniform color and no obvious defects or damage.
The lines of the aluminum-plastic composite cover should be clear, without blurring or breakage.
The lid surface of the aluminum-plastic composite cap should be completely adhered to the bottle mouth without any twisting or curling phenomenon.
If there are any appearance issues, it may affect its sealing performance and require special attention.
Water immersion test:
Invert the bottle containing liquid in the water so that the liquid level is higher than the bottle mouth.
Observe whether the aluminum-plastic composite cap around the bottle mouth leaks. If there is leakage, it indicates that there is a problem with the sealing performance.
At the same time, check whether the lines of the aluminum-plastic composite cover are complete and clear. The breakage or deformation of lines may also indicate poor sealing performance.
Airtightness testing:
Conduct a sealing test using a pressure pump, data collector, and pressure sensor to measure the pressure changes inside and outside the cover.
According to GB15171 standard, the sealing performance of aluminum-plastic composite covers is evaluated by assessing the pressure change.
Leak proof testing:
Use liquid immersion method or air pressure method to detect whether the aluminum-plastic composite cover will leak under normal use conditions.
This can help further confirm whether the sealing performance of the aluminum-plastic composite cover meets the standard.
Through the above steps, the sealing performance of aluminum-plastic composite covers can be comprehensively and systematically checked to ensure that they can achieve the expected sealing effect in practical applications.