How to check the sealing performance of paint cans?

1. Water immersion method:
Operation steps: Fill the paint can with water, make sure there is no air left in the can, and then completely immerse it in water to observe whether there are bubbles. If bubbles keep coming out, it means that the paint can is leaking and the sealing performance is poor; if no bubbles come out, it means that the sealing performance of the paint can is good.
Scope of application: It is suitable for paint cans of various materials and specifications, but for some larger or heavier paint cans, the operation may be more difficult.
2. Inflation method:
Operation steps: Fill the paint can with a certain pressure of gas (such as air or nitrogen) through a special inflation device, and then put it in water or use soapy water to apply it to the can mouth, welds and other parts that may leak, and observe whether bubbles are generated. You can also use equipment such as pressure sensors to monitor the pressure changes in the can. If the pressure drops beyond a certain range, it means that there is a leak.
Scope of application: It is suitable for all types of paint cans, especially for some paint cans that cannot be tested by water immersion method (such as paint cans with electronic components inside or that are not allowed to contact water).
3. Vacuum method:
Operation steps: Put the paint can into the vacuum box, use the vacuum pump to extract the air in the vacuum box, make the paint can in a vacuum state, and then observe whether the paint can has signs of deformation, cracking or leakage. You can also set a pressure sensor in the vacuum box to monitor the pressure changes in real time.
Scope of application: It is suitable for some paint cans with high requirements for sealing performance, such as paint cans used to store highly volatile paints or in special environments.
4. Weighing method:
Operation steps: First weigh the initial weight of the paint can, then seal the paint can, and weigh it again after a period of time. If there is no obvious change in the two weights, it means that the sealing performance of the paint can is good; if the weight increases or decreases, there may be leakage or other problems.
Scope of application: It is suitable for paint cans of various materials and specifications, but for some paint cans with larger weight or higher precision requirements, high-precision weighing equipment is required.
5. Ultrasonic detection method:
Operation steps: Use an ultrasonic flaw detector to emit ultrasonic signals to the paint can. When the ultrasonic wave encounters a leak, reflection, refraction and scattering will occur. By analyzing the received ultrasonic signal, it is possible to determine whether the paint can has a leak and the location and size of the leak.
Scope of application: Applicable to paint cans of various materials, especially for some metal paint cans, the detection effect is better.
6. Helium mass spectrometry leak detection method:
Operation steps: After evacuating the paint can, fill it with a certain amount of helium, and then use a helium mass spectrometer leak detector to detect whether there is a helium leak outside the can. The helium mass spectrometer leak detector has extremely high sensitivity and can detect extremely small helium leaks.
Scope of application: Applicable to paint cans with extremely high sealing performance requirements, such as paint cans used in high-precision fields such as aerospace, electronics, etc.