Views: 4 Author: finetry Publish Time: 2021-02-20 Origin: Site
Aerosol products have four major components, aerosol cans, valves, feed liquid, and propellant gas. Due to the difference in product formulas, we often need to consider the corrosiveness and pressure resistance between the filling material and the container when choosing packaging materials. We know that there is a water-based aerosol product that is highly corrosive to the tank. Therefore, the key problem of filling water-based aerosol products is the corrosion of the can, and the quality of the aerosol can directly affects the corrosion resistance. There are many factors that affect the quality of aerosol cans, from raw materials, can making equipment and processes to quality inspection, etc. The following is a brief introduction:
1. The quality of tinplate itself:
Tinplate substrates used for can manufacturing require high purity. For example, if the impurity content is too high, it affects the processing performance and corrosion resistance such as ductility, brittleness, hardness, etc. At present, most of our tinplate substrates are imported from abroad. In order to reduce costs, some manufacturers use low-quality thin tinplate cans. Tinplate itself has tiny trachoma, which leads to leaky cans. Special care should be taken when selecting.
2. Quality of tank body welding and repainting:
For tinplate cans, one of the weakest links is the weld seam. In addition to the strict mechanical performance requirements, the weld seam is easily corroded due to the destruction of the tin layer, so recoating is a key technology for three-piece cans. Many water-based product leaks are caused by the incompatibility of the recoating and the contents. In addition, unstable current or unstable copper wire quality are all prone to product soldering and form leakage points.
3. Type and density of inner coating:
Inner coating is one of the effective anti-corrosion methods for water-based products (except for DME as a propellant), but the quality of the inner coating material and the coating process will affect the corrosion resistance of the product, such as some coatings are not easy to find with the naked eye The bubbles, the electrochemical reactions appearing in these places are particularly strong, and corrosion and rust are prone to occur over time, so that they can wear through the can, especially where the top and bottom covers are in contact with the welding seam of the can body. The compactness of the product is even more important, and many leaks of water-based products appear in this place. At present, epoxy-phenolic, imide-epoxy, PVC, etc. are used for inner coating. The most used is epoxy-phenolic, but the quality of different manufacturers is different. Compatibility test should be done when selecting.
4. Sealing quality:
Good sealing equipment and process is an effective guarantee for the sealing performance of aerosol cans, and the amount of hooking of the roll seal is an important indicator of detection. If the control is not good (including production process and detection), it is easy to cause undetectable micro leak.
5. Leak detection:
Most aerosol products are flammable and explosive. Each aerosol can must be tested by an online pressure leak detector. At the same time, the sampling pressure of deformation pressure and burst pressure must be checked according to the regulations to ensure product production, storage, Safety during transportation and use. In order to reduce costs, some manufacturers fail to conduct leak detection according to regulations, and these tanks are likely to have potential quality or safety risks.
The sealant can only be achieved between the body of the aerosol can and the lid to meet the sealing requirements. The selection of good sealant and gluing process is crucial to the quality of the can. In addition to the strict control of the quality of the sealant itself, the sealant is The swelling and dissolution properties of various solvents, especially strong solvents, DME, etc. must be tested strictly and for a long time. Otherwise, the sealant will be damaged and leakage will occur. Problems such as broken or uneven distribution, blistering, and insufficient amount of glue during glue application are prone to problems. Because the contents of aerosols are very different, and the sealing performance cannot be determined in a short time, the quality of the sealant must be guaranteed by the long-term production experience of the can manufacturer and strict quality control.