Businesses that package and transport materials from one location to another should use protective packaging. To maintain a product in excellent condition, it must be protected from moisture and other corrosion-causing impurities. Metals, particularly iron, are particularly susceptible to corrosion because of excessive moisture exposure. v, or VCI for short, are many solutions to deal with corrosion. VCIs are chemical substances that prevent corrosion inside a container. They are highly effective for ferrous and non-ferrous metals.
Here are some of the common questions asked about VCI.
How does VCI work?
The procedure entails releasing rust-inhibiting chemicals into a closed environment. Creating an enclosed space requires wrapping the metals with airtight packaging, usually consisting of poly film or paper. Once enclosed, the VCI molecules start to circulate the metals and inside the plastic bag. They form an invisible coating surrounding the metal that is only a single molecule thick. As the metal does not react to the two components that produce rust – surrounding air and moisture, product protection is guaranteed. Most importantly, the VCI compounds’ protective barrier is not toxic or hazardous during unpacking.
What are the Different kinds of VCI Products?
- Paper – Available for applications that require metal products to be wrapped or layered inside a container. The paper is coated with VCI on both sides, providing all-around protection.
- Film – Ideal for more oversized items and equipment. They are available in film rolls that unwind and reveal a plastic film that uses vapor corrosion inhibitors to coat and protect metal surfaces from corrosion.
- Liquid – Once the VCIs have adsorbed on the surface of the metal, they form a hydrophobic barrier that prevents moisture from penetrating the metal
- Emitter – Lightweight, slim, and compact disks containing corrosion that allow accessibility into tight and restricted spaces to provide rust protection
- Bags – Coated completely with VCI compounds that serve as barriers between the metal and the corrosive substance. Ideal for assembly and packaging lines
- Powder – Lay-up, preservation, and mothball applications protect the void areas of interior cavities. Applied by dusting, fogging enclosures with a low-pressure air hose or as a solution
What is the Shelf Life of VCI Products?
The shelf life is when unused VCI products can be stored before use without losing their effectiveness. Most VCI products have a shelf life of up to two years when the product is stored in an external bag or box, out of direct sunlight, and under shelter.
What are Ferrous and Non-Ferrous Metals?
- Ferrous: Iron, steel, and cast iron metals
- Non-Ferrous: Aluminium (and aluminium alloys containing copper or manganese), copper, brass, bronze, and fully galvanised steel
- Multi-Metal: Products that contain combinations of Ferrous and Non-Ferrous metals
Is VCI Film better than VCI Paper? What are the differences between them?
Both packaging products are helpful, but one may be a better option depending on the application. VCI Paper releases VCIs more rapidly than VCI Film. VCI Film acts as a barrier to water vapour, whereas VCI Paper readily absorbs moisture. The application should be oriented toward the goods to be protected. To find out more about which VCI products are more suitable for your needs, speak to our experts today.
Will VCI be affected by Enclosures that are not Entirely Sealed?
This depends on the chemical contaminants in the atmosphere, relative humidity, temperature, and several factors. The level of protection will depend on the level of contaminants in the air and air exchange rate. Some of the vapours will escape when a container is opened. However, the VCI that is already adsorbed on the metals will not be disrupted immediately and will continue protecting the metal. The lifetime of the device will be shortened, possibly to one year or less.
Can VCI Products be Reused?
VCI products can be reused if they are dry, clean, and undamaged. Small holes in the VCI Film material can be sealed with adhesive tape. VCI Bags with large holes, tears, or have begun to crack or lose strength due to excessive exposure to direct sunlight will not provide adequate corrosion protection and should not be reused.
How to Seal Products with VCI?
A tightly sealed VCI packaging yields better volatile corrosion protection. Seal closed with zip-ties, packaging tape, or staples. A good closure is to fold over the film and either tape or staple the area shut. The best seal is always a heat seal. Water must be prevented from entering the packaging.
- Wrap individual metal parts, components, or equipment using VCI Paper
- Before placing the metal parts in a shipping container, line the bottom of the crate with VCI Film or Poly Bags
- Place a layer of parts wrapped in VCI Paper in the crate
- Before adding a new layer, interleave VCI Paper on top of the first layer
- If a wooden crate is used as a base or a pallet is used to brace the packaging environment, it is vital to wrap or cover any wood areas to prevent acidic moisture from contacting metal surfaces
- If corrugated cardboard separators are used between metal parts, be sure to interleave VCI Paper between the cardboard and the metal parts, as these separators can be a significant source of corrosion
How long can parts be expected to remain free of corrosion after removal from a VCI Package?
Tests performed with electron scanning (ESCA) microscopy show that 2-4 hours after a steel test panel is removed from a VCI package, all traces of the corrosion inhibiting molecular layer are gone from the part’s surface.
What is the Difference between VCI & Desiccants in Preventing Corrosion?
VCI products and Desiccants prevent corrosion in different ways. VCI products prevent corrosion by an electrochemical process that forms a thin molecular layer of protection on a metal surface. This layer of protection is microscopic and does not alter the metal in any way. A desiccant is merely a moisture absorber. Desiccants absorb moisture but do not satisfactorily protect a metal surface from other electrolytes that cause corrosion, such as oxygen. However, using both VCI and Desiccants is also possible.
Do Hot or Cold Temperatures affect VCI Products?
Cold temperatures do not significantly affect the performance of VCI Paper. At high temperatures, VCI will release its corrosion protective ions into the enclosed atmosphere faster. However, when emitters are used continuously at these higher temperatures, we suggest that they be replaced more often as the valuable lifetime and period of corrosion protection will be shorter.
Here is a video about Volatile Corrosion Inhibitors (VCI).