What is VCI, and how does it affect your packaging?

Even if your business ships metal parts, components, or products, you may still need to ask what VCI is, and be unaware of how it affects your packaging and processes.

VCI stands for Volatile Corrosion Inhibitor. VCIs are chemical compounds that release anti-corrosion molecules into a sealed air space, protecting exposed metal surfaces from corrosion. These inhibitors are incorporated into packaging materials, such as paper and plastic. VCI packaging prevents rust and corrosion during the storage, handling, and shipping of metal products.

In this guide we’ll cover:

• What is VCI, and how does it work?
• The types of VCI packaging available.
• The advantages it offers.
• How to use it correctly.

Corrosion is the slow breakdown of metals from exposure to air, moisture, or chemical reactions (such as acids) on their surface. When this happens, certain metal materials rust, becoming unusable.

Iron and steel are susceptible to rust and should, therefore, be protected with VCI packaging. Metals containing zinc, magnesium, and copper also require VCI packaging.

Corrosion can affect numerous industries, including construction, automotive, aerospace, and marine sectors. Ensuring protection is crucial if you produce, store, handle, or ship metal-based products in these (or any other) fields.

VCI packaging protects metal parts from corrosion, a pervasive and costly problem, particularly during storage and distribution. Traditional anti-corrosion methods can be messy, expensive, and hazardous to both personnel and the environment.

VCI packaging works by continuously releasing a blend of special chemicals that vaporise to create anti-corrosion gases.

Inside the sealed airspace of VCI packaging, these chemicals form a microscopic, invisible layer on the metal surfaces, blocking the electrochemical processes that cause rust.

VCI passivates the electron flow between anodic and cathodic areas on metal surfaces, providing comprehensive protection. This protective layer saturates the air inside the packaging and penetrates crevices, slots, and otherwise unreachable areas of the metal parts, ensuring total protection.

Effectively, VCI makes affected metals unreactive by altering the surface layer.

Whilst VCI stands for Volatile Corrosion Inhibitor, various companies might use different names and abbreviations. Examples include:

• VCI – Vapor Corrosion Inhibitor
• VPI – Vapor Phase Inhibitor
• VPI – Volatile Phase Inhibitor
• VPCI – Volatile Phase Corrosion Inhibitor
• VPP – Vapor Phase Paper
• MPI – Metal Phase Inhibitor

Essentially, all these terms refer to the same chemical process. Companies adopt different names or abbreviations for marketing purposes.

There are several different VCI packaging options, each with slightly different properties and used in somewhat different ways.

Types of VCI packaging include:

• VCI bags.
• VCI papers.
• Cardboard boxes with VCI coating.
• VCI stretch wrap.
• VCI bubble wrap.
• VCI fabric.

It may seem obvious if you’re shipping metal products, but VCI packaging offers numerous advantages.

Anti-corrosion packaging prevents metal corrosion during storage and transit. It can also protect machine parts when they are not in use.

To minimise the risk of corrosion, you should package metals immediately.

Products must be clean and thoroughly dried before packing. Even small amounts of water can cause corrosion inside anti-corrosion packaging.

For long-term storage, regular inspections are recommended to ensure the packaging remains undamaged and effective. Anti-corrosion packaging should be replaced every 2-3 years.

Anti-corrosion packaging is effective in most environments, provided it is shielded from extreme conditions like freezing temperatures or excessive heat. It is essential to prevent the packaging from becoming too wet, as moisture increases the risk of contamination or failure.

VCI packaging can often be reused if it is kept clean, dry, and free from damage, which adds to its cost-effectiveness.

The corrosion-inhibiting compounds that actively prevent surface corrosion do not impact the metal’s performance.