Volatile Corrosion Inhibitors
click image to enlarge
When a VCI product has been added to a package or enclosure, a protective vapour is released and a thin protective layer of one or two molecules thick is formed on the surface metal. This film is invisible to the naked eye. It prevents any corrosion accelerating agents from reaching the surface of the metal and corrosion is prevented. Corrosion that has already commenced will be halted. A VCI provides clean protection whereby it produces no residue or aroma and has no effect upon the electrical or mechanical properties of the product.
VCIs can provide effective protection for up to 5 years and, with a wide range of formats available, they can protect both accessible and inaccessible surfaces. Yet, the protection provided is invisible and products arrive in pristine condition and are professionally presented. Furthermore, VCIs are cost effective because their properties can reduce customer complaints, claims and restoration costs. Packaging destruction is eliminated and repackaging costs are minimised when periodic inspections are required. VCIs often save human resources in comparison to that required for traditional packing and unpacking methods.
VCI Formats
Although paper and polythene are the most commonly used forms of VCI, they are available in a variety of other impregnated materials. Each form of VCI is itself produced in a range. For example, there are an assortment of types of paper available, each having distinctive characteristics to suit a particular application.
There are several key factors to consider when selecting the correct VCI format. These include the metal type, the product shape, the length of time protection is required, whether the VCI will be required to protect from abrasion and shock damage as well as corrosion and the climatic conditions the product and packaging will be subjected to during transit and storage.
Papers - available in several different thicknesses that can be effective on one or both sides. There is a wide choice available including creped, waterproof, water-repellent, flame-resistant and sealable.
Polythene - can be dual purpose in that it can be used, most typically, as a lining material for export cases, whilst protecting industrial products from tarnishing. Where transparent film is used, goods can be
inspected at any time.
Powder - ideal for use in cavities where it is difficult to use or remove paper such as in boilers, tanks, pipes, containers and barrels. Powder VCI can be supplied in bags or in loose packs for scattering or blowing into hollow spaces within metal structures.
Vapour Capsules - suitable for use where a high concentration of active substances are required for protecting products such as cans, boxes and blister packs. The capsules can be affixed on any surface.
Oil - provides direct contact protection for product surfaces; tiny
quantities of corrosion-prevention substances are released into the air above the film of oil and in an enclosed space, this can build-up a
permanent protective atmosphere.
Bubble film and foam sheeting - flexible, light-weight padding to
protect delicate product parts, such as polished cylinders and axles from
abrasion and shock damage whilst providing simultaneous protection from corrosion.
Corrugated plastic and board - provides weather resistant, durable and reusable product protection.
Selecting a Compatible VCI
VCIs should be selected to be fit-for-purpose because of the variance of their protective qualities. It is essential that a VCI is compatible with the surface it is required to protect such as ferrous metals (iron, steel, alloys of iron and steel), non-ferrous metals (aluminium, copper, brass and bronze), products that are a mixture of both and silver surfaces. An incorrectly selected VCI may encourage corrosion rather than prevent it.
- Protects metal surfaces from attack by corrosion accelerating agents.
- Provides clean protection - produces no residue or aroma.
- Has no effect upon the electrical or mechanical properties of the product.
- Up to 5 years product protection.
- Available in a range of formats to protect the widest range of products.
- Flexible to protect all shapes of product.
- Cost-effective anti-corrosion packaging solution.
