The sealing function of the bottle cap refers to the sealing ability between the bottle cap and the bottle mouth to block or slow down the leakage of liquid and gas in the bottle. For all plastic anti-theft bottle caps, sealing is one of the important functions. Today, The manufacturer of the capping machine will tell you about the test method of the sealing function of the cap:
Many outsiders may think that the sealing ability of the bottle cap is provided by the thread, but in fact, the thread of the bottle cap and the thread of the bottle mouth are clearance fit and do not have any sealing ability. There are 3 areas where the bottle cap can provide sealing ability, followed by The inner seal, outer seal and top seal of the bottle cap. Each sealing area has a certain amount of deformation with the bottle mouth, and this deformation continuously exerts a certain force on the bottle mouth, thereby producing a sealing effect. Not all bottle caps are used 3-way seal, but most bottle caps use inner and outer seals. For bottle cap manufacturers, the sealing function of the bottle cap is an item that needs continuous monitoring, that is, the sealing function needs to be regularly tested. There may be many small-scale The bottle cap factory does not pay much attention to the test of the sealing performance of the bottle cap. Some people may choose the original simple method to test the sealing performance, such as hand squeezing and foot stepping after the bottle cap is sealed.
1. Non-inflatable cap: sealing requirements, no air leakage at 200kpa, no capping at 350kpa. After the bottle cap is sealed at the rated torque, pressurize it to 200kpa with a sealing tester, and keep the pressure underwater for one minute to check whether there is leakage Then pressurize to 350kpa, keep the pressure for one minute, and check whether the cap comes out.
2. Carbonate cap: sealing requirements, no air leakage at 690kpa, no capping at 1207kpa. After sealing the cap with the rated torque, pressurize it to 690kpa with a sealing tester, keep the pressure underwater for one minute, and investigate whether there is any Air leak, then pressurize to 1207kpa, keep the pressure for one minute, and check whether the cap comes off.
The principle of the sealing and testing instrument is relatively simple, that is, screw the cap to be tested on the corresponding preform, inject compressed air, put the cap and preform below the water level, and check whether there are bubbles emerging. Its structure is relatively simple, consisting of It consists of several parts: 1, compressed air source. 2, excitation meter. 3, gas pipeline. 4, main frame. 5, liquid tank. 6, pressure regulating valve.
