Clicking (clip clapping noise) on cans

The “clinking” or “clip clapping” noise in cans, especially in twist-off type closures, can be caused by several factors. Based on available information, some of the reasons why this phenomenon may occur include:
Problems in the seaming process: If the twist-off lids are not aligned correctly during assembly or if the pressure applied during the first seaming pass is insufficient, this can lead to a defective seaming that could generate noises when handling the can.

Physical defects in lids or can bodies: A defective can body flange or a totally crushed lid curl can be causes of improper sealing, which in turn could result in abnormal noises.

Interference or damage to the cover: If there is excess sealing compound or material in the weld, or if there is inclusion of foreign material in the double seam or by crossover with the side weld, this could affect the integrity of the seal and cause noise.

Possible effects of a defective seal on twist-off caps include:
Loss of airtightness: An inadequate closure can lead to the loss of airtightness of the package, which is crucial to maintain the quality and safety of the packaged product.

Product contamination: If the closure is not airtight, there is a risk of external contaminants entering the container and affecting the quality of the product.
Microbiological spoilage: Loss of airtightness can lead to microbiological spoilage of the food, which represents a risk to public health.
To avoid these problems, it is important to ensure good fit and alignment during the closing process, as well as regular inspection and maintenance of the closing equipment to guarantee the quality and safety of the twist-off containers.