VCI Corrosion Protection: VCI Paper, Bags & Packaging for Metal Parts
THE COMPLETE GUIDE TO
VCI CORROSION PROTECTION
Everything you need to know about VCI paper, poly bags, and sprays for protecting metal parts during shipping and storage.
WHY VCI?
Metal parts and machinery are among the most valuable commodities shipped in the US and globally. Many of these parts, especially those made of iron or mild steel, are highly prone to rust and corrosion. VCI (Volatile Corrosion Inhibitor) packaging materials provide effective, long-lasting corrosion protection during storage and transit, helping manufacturers and shippers avoid costly damage claims and ensure parts arrive safely. VCI packaging is widely used in the automotive, aerospace, and metal fabrication industries.02 Product Types
03 Compatible Materials
04 Best Practices
05 VCI vs. Desiccants
06 FAQs
07 Related Articles
What is a VCI?
A Volatile Corrosion Inhibitor (VCI) is a compound that vaporizes into the air to help prevent metal corrosion. It can be incorporated into packaging materials such as paper and plastic.
How does it work?
Inside a sealed package, VCI molecules form a thin protective layer on metal surfaces. This molecular layer helps isolate the metal from moisture, oxygen, and other contaminants.
HOW DOES VCI TECHNOLOGY PREVENT CORROSION?
Corrosion is a chemical process where metals interact with oxygen and water to form metal oxides, commonly known as rust. VCI technology interrupts this process at the molecular level.ION BARRIER
VCI molecules are attracted to the metal surface and form an ion barrier that prevents water and oxygen from reaching it.
WATER DISPLACEMENT
VCI molecules adsorb onto the metal surface, helping separate the metal from moisture and corrosive contaminants.
OXIDATION PREVENTION
By blocking oxygen and water from interacting with the metal surface, VCIs stop or significantly slow the oxidation process.
RESIDUE-FREE REMOVAL
When packaging is removed, the molecular layer dissipates quickly and cleanly. No degreasing or cleaning is required before use.
VCI PAPER, POLY BAGS & SPRAYS
VCI packaging is available in three formats, each designed for different part shapes, sizes, and protection needs.
VCI PAPER
Kraft paper permeated with VCI compounds. Available in ready-to-use sheets or rolls for larger parts. Provides corrosion protection plus shock absorption and void fill.BEST FOR:
Wrapping small to medium parts
Sharp or irregular shapes
Metal supports, brackets, and components
Short to medium-term shipping and storage
VCI POLY BAGS
Available from small flat bags for individual parts to large gusseted bags for entire pallets or equipment. Transparent for easy content identification without opening.BEST FOR:
Flat parts: gears, nuts, bolts, sheet metal
Dimensional parts: engine blocks, tools
Gaylord liners inside crates or cartons
Superior dust, dirt, and moisture protection
VCI SPRAYS
Applied directly to the metal surface to form a corrosion-resistant barrier. The part can then be packaged using standard materials. Can be refreshed periodically for long-term storage.BEST FOR:
Long-term storage of large items
Engine blocks, molds, and tooling
Parts that need periodic re-protection
Surfaces that are difficult to wrap or bag
STILL NEED HELP DECIDING?
Reach out to one of our Benchmark reps who can help you find the right product for your needs.
WHAT CAN VCI PROTECT?
VCI packaging provides effective corrosion protection for a wide range of metals while remaining safe for use with many common non-metallic materials. Review the compatibility guidelines below to determine whether VCI is suitable for your application.METALS VCI IS DESIGNED FOR
VCI is most effective on ferrous metals and alloys that are highly susceptible to corrosion:
- Steel and mild steel
- Iron and cast iron
- Iron-containing alloys
Other metals such as copper, chrome, and aluminum may also benefit from VCI protection to prevent undesirable surface characteristics.
NON-METALIC MATERIALS
VCI paper and poly bags are considered safe to use alongside:
- Electronics
- Rubber
- Plastic
- Wood
Do not use VCI with:
Food products or items intended for human or animal consumption
Materials with unknown chemical compatibility (contact manufacturer)
GETTING THE MOST FROM VCI PACKAGING
VCI packaging works best when used correctly. The most common cause of failure is user error, not product failure.VCI paper: approximately 2 years when stored correctly
VCI poly bags: up to 3 years when stored correctly
Store away from heat, moisture, and excess air exposure to maximize shelf life
Completely enclose the part: paper must wrap fully, bags must be sealed
Minimize air inside the package
Do not open packaging during storage: the protective layer dissipates within hours once exposed
Clean and dry parts before packaging: VCI will not reverse active corrosion
Do not inhale or ingest VCI chemicals
When using sprays: wear gloves, mask, and eye protection
Use an eyewash station if spray contacts eyes
Wash hands after handling VCI paper or poly bags
Never use VCI to wrap food products
SECTION 05
VCI VS. DESICCANTS: ACTIVE OR PASSIVE CORROSION PROTECTION?
Both VCI products and desiccants protect metal from corrosion, but they work very differently. For high-value or corrosion-prone parts, using both together provides the most complete protection.| VCI PRODUCTS | DESICCANTS | |
|---|---|---|
| Protection type | Active: vapor-phase molecules adsorb onto the metal surface to help form a protective layer | Passive: absorbs moisture from the air like a sponge |
| How it works | Molecular layer helps isolate the metal surface from oxygen, moisture, and other contaminants | Reduces relative humidity inside the package to slow corrosion |
| Best for | Ferrous metals with high corrosion risk; precision parts | Humidity-sensitive products; electronics; general moisture control |
| Can be combined? | Yes: VCI + desiccant together provides the most complete protection for high-value metal parts | |
COMMON QUESTIONS
Answers to the questions we hear most about VCI.
What does VCI stand for?
VCI stands for Volatile Corrosion Inhibitor, sometimes called a Vapor Corrosion Inhibitor. "Volatile" refers to the fact that the chemical compound vaporizes in air to protect the metal.
What is the difference between VCI paper and VCI poly bags?
VCI paper is better for sharp or irregular parts that might puncture a bag, and also provides cushioning. VCI poly bags are better for dust and moisture protection and allow visual inspection of contents without opening.
How long does VCI protection last?
When stored correctly, VCI paper provides approximately two years of protection and VCI poly bags up to three years. Once the packaging is opened, the molecular layer dissipates within hours.
Is VCI packaging safe to use with electronics?
VCI paper and poly bags are considered safe with electronics, rubber, plastic, and wood. VCI molecules do not react with most common non-metallic materials. If you are unsure about a specific material, contact us or the manufacturer.
Will VCI remove existing rust?
No. VCI prevents corrosion but will not reverse it. Parts should be thoroughly cleaned to remove any rust before packaging.
Do I need to clean the part after removing VCI packaging?
No. The molecular layer dissipates quickly after the packaging is removed, leaving no residue. Parts are ready for use without additional cleaning.
Can VCI and desiccants be used together?
Yes. Combining VCI packaging with desiccants provides both active corrosion protection (VCI) and passive moisture control (desiccant), which is the most effective approach for high-value metal parts.
Is VCI worth the extra cost?
VCI packaging is significantly more expensive than standard paper or poly bags. However, when compared to the cost of replacing corroded parts or filing damage claims, VCI provides strong value for corrosion-prone shipments.
KEEP LEARNING
Explore more tape and packaging guides from Benchmark Industrial.Desiccant Guide
How silica gel and other desiccants absorb moisture to protect products during shipping and storage.
Protective Packaging Guide
Bubble wrap, foam, air pillows, and more: how to protect products inside the box.
Pallet Containment Solutions
Pallet covers, stretch film, and strapping options for securing loads during transit.
Corrugated Guide
Learn how to choose the right corrugated box for your product.
Shop Benchmark's full selection of VCI products, or contact us for
product recommendations, sizing help, and corrosion-protection guidance.