PET bottle refers to a plastic material called polyethylene terephthalate (polyethylene terephthalate), or PET for short, which is a compound of terephthalic acid and ethylene glycol. produced polymers. PET plastic has the characteristics of light weight, high transparency, impact resistance and not easy to break. It can also block carbon dioxide gas and keep soda water “gas”. PET bottles have strong applicability and are widely used in daily necessities, daily chemical packaging and other fields.
PET bottles are reprocessed by blow molding to form plastic bottles, including bottles for cosmetics, medicine, health care, beverages, mineral water, reagents, etc. A method of blow molding to form PET plastic bottles.
Quality inspection of PET bottles
The routine testing of PET bottles includes verticality, bottle wall thickness testing, compression testing, cap opening, sealing and other testing items.
The test items in this article are based on the standard
QB2357-1998 polyester (PET) non-carbonated beverage bottle
GBT17876-2010 Plastic anti-theft caps for packaging containers
Verticality
According to the provisions of 5.2.4 in QB1868.
Sealing performance
Fill 5 sampling bottles with water of nominal capacity and twist (buckle) the cap tightly. Place the sample horizontally on a plane for 8 hours before checking.
Vertical load
Place five sampling bottles at 23±2°C for more than 2 hours, apply vertical pressure on the sample bottles at a constant speed of 100mm/min on the testing machine, record the maximum load of each sample for the first time, and take the arithmetic mean value.
Drop performance
Fill 5 sampling bottles with water at 20±5°C according to the nominal capacity, cover them well, and conduct a drop test on the concrete floor. The drop height is 1.8m, the bottle mouth is upward, and it falls freely.
Summary of bottle cap test items
Sealing performance test
Use a capping machine to seal the non-carbonated cap according to the rated torque that meets the requirements, test it with a seal tester, pressurize to 200kPa, keep the pressure under water for 1min, observe whether there is air leakage, then increase the pressure to 350kPa, and keep the pressure for 1min , observe whether the bottle cap is loose and pops up.
Use the capping machine to seal the carbonic acid cap according to the rated torque that meets the capping requirements, cut off the anti-theft ring, test with a seal tester, pressurize to 690kPa, keep the pressure under water for 1min, observe whether there is air leakage, and then increase the pressure to 1207kPa, keep the pressure for 1min, and observe whether the bottle cap pops out.
Drop performance
After injecting the nominal volume of water into the bottle, use a capping machine to seal the non-carbonated cap according to the rated torque that meets the capping requirements, and test according to the following requirements to observe whether the cap is flying off and whether the seal is leaking.
After filling the bottle with carbonated water with a nominal capacity of Chinese 4.2±0.1 volume of carbon dioxide, use a capping machine to seal the carbonated cap at a fixed torque that meets the capping requirements, and test according to the following requirements to observe whether the cap is flying off and whether the seal is Leakage
