The sealing performance of plastic bottle caps such as food and beverage bottle caps is very important for the protection 

of products, which can effectively ensure the shelf life of food and its safety and hygiene. Plastic anti-theft bottle caps 

are required to be easy for consumers to open, while also avoiding leakage problems caused by poor sealing performance.

1、 Sealing performanceWithout gas cap, there is no air leakage or cap detachment at 200kpa

No air leakage at 690kpa with gas cap, no air leakage at 1207kpa

2、 What testing instrument is used for the sealing test of plastic bottle caps

The LT-03A positive pressure sealing tester developed and produced by Puchuang Industrial Technology is used to 

quantitatively measure the leakage and sealing performance of various standard plastic anti-theft bottle caps

 (including gas caps and non gas caps) with thread diameters of 28mm and 38mm. It can also evaluate and analyze

 the torque sealing index, connection and detachment strength of bottle caps, as well as the overall sealing, 

compression resistance, and rupture resistance of the bottle body. It is also known as a plastic bottle cap sealing 

tester, plastic anti-theft bottle cap sealing detector, etc.

LT-03A Leak and Seal Strength tester

3、 Test method for sealing performance of plastic anti-theft bottle caps Test operation steps

(1) Cut off the anti-theft ring (strip) from the non gas cover, seal it with a rated torque of not less than 1.2N. m, test 

it with a sealing tester, pressurize it to 200kPa, and hold it underwater for 1 minute to observe if there is any air 

leakage or detachment

(2) Cut off the anti-theft ring (strip) from the gas containing cap, seal it with a rated torque of not less than 1.2N. m, 

test it with a sealing tester, increase the pressure to 690kPa, and hold it underwater for 1 minute to observe if there 

is any air leakage. Then increase the pressure to 1207kPa and hold it for 1 minute to observe if the cap has come loose.