How to check the sealing performance of glue can?

1. Simple observation method: directly check the appearance of the glue can, check whether the lid is tightly closed, and whether there are any deformation, cracks or damage that may affect the sealing. For glue cans with sealing gaskets, check whether the gasket is installed correctly, intact and has no signs of aging, deformation, etc.
2. Pressure test method:
Inflation test: If the glue can has a suitable inflation port or can be connected to an inflation device, you can fill the can with a certain pressure of gas (such as air), and then immerse the glue can in water to observe whether there are bubbles. You can also use professional air tightness testing equipment and set the corresponding pressure parameters for testing. If you hear obvious gas leakage during inflation, or see a large number of bubbles continue to emerge in the water, it means that the sealing performance is poor.
Vacuum test: For some special glue cans, you can also use vacuum testing. Draw a certain degree of vacuum inside the glue can, and then observe whether the glue can maintain a vacuum state, and whether air leaks in and causes the vacuum degree to decrease.
3. Smear test method: Apply some sticky and easy-to-observe substances, such as water-soluble pigments, vaseline, etc., to the joint between the lid and the can body of the glue can. Then cover the lid and press it appropriately to make it sealed. After a period of time, open the lid to check whether the smeared substance has entered the can or has abnormal flow or diffusion in the sealed part. If so, it may indicate a problem with the seal.
4. Weighing method: First weigh the unopened and well-sealed glue can and record the weight. Then place the glue can for a period of time (simulating the time of normal use or storage) and weigh it again. If the weight increases significantly, it may be because external air or other substances have entered the can, indicating that the sealing performance is not good; if the weight decreases significantly, it may be that the glue in the can is leaking. However, this method may not be very accurate for some small-capacity glue cans, because the weight change may be relatively small and difficult to detect.
5. Functional test: If the glue can is used in a specific device or process, an actual functional test can be performed. For example, connect the glue can to the corresponding glue coating equipment, apply glue according to the normal operating procedures, and observe whether the glue supply is stable during the coating process, and whether there is leakage or dripping. If the glue supply is unstable or leaking, in addition to checking the problem of the equipment itself, it is also necessary to consider whether the sealing performance of the glue can is qualified.
6. High or low temperature test (optional): If the glue can may encounter high or low temperature environment during use, the glue can can be placed in the corresponding extreme temperature conditions (note that it must be within the temperature range that the glue can can withstand) for a period of time, and then check its sealing performance. Because temperature changes may cause the material to expand or contract, thereby affecting the sealing effect. For example, at high temperatures, the sealing gasket may become soft and deformed, reducing the sealing performance; at low temperatures, the material may become brittle, increasing the risk of cracking or leakage. This test can more comprehensively evaluate the sealing reliability of the glue can under different environmental conditions, but it is necessary to pay attention to operating safety and avoid damage to the glue can.
7. Long-term storage test: Fill the glue can with glue (or simulate the actual filling amount) and seal it, and place it in a specified storage environment (such as normal temperature and suitable humidity) for a period of time (weeks, months or even longer, depending on the use cycle and requirements of the glue can). During storage, regularly check the appearance, weight and glue status of the glue can. If the glue can is found to be deformed, leaking, glue drying or deteriorating during long-term storage, it may be related to poor sealing performance.
8. Drop test (optional): For some glue cans that need to have certain drop resistance, drop tests can be performed. Drop the glue can freely from a certain height (determined by the design and use scenario of the glue can) onto a hard ground or test platform, and then check whether the glue can is cracked, deformed, and whether the seal fails. The drop test can simulate the stress of the glue can in transportation, handling or accidental drop, and evaluate its structural integrity and sealing performance, but pay attention to controlling the drop height and number of times to avoid excessive damage to the glue can.