Rust never announces itself. Equipment goes into storage looking factory fresh and comes out months later with corroded machined faces, seized fittings and oxidised electricals. For businesses storing metal assets around Perth, where humid coastal air and salt exposure near WA ports accelerate corrosion, protecting equipment properly from day one is far cheaper than restoring it later.
VpCI, short for Vapour phase Corrosion Inhibitor, is one of the most effective and widely specified technologies for preventing that damage. This guide explains what VpCI is, how it works, and how to use it to keep equipment corrosion free through long-term storage, transport and export.
What Is VpCI?
VpCI stands for Vapour phase Corrosion Inhibitor. It is a corrosion protection technology in which specially formulated compounds release an invisible, protective vapour inside sealed packaging. The vapour settles on metal surfaces as a molecular layer that blocks the electrochemical reaction that causes rust, tarnish and oxidation. Unlike oils, greases and traditional rust preventatives, VpCI protection is clean, dry and invisible, and equipment can typically be put straight into service without cleaning or degreasing. VpCI technology is delivered through products such as films, emitters, coatings and desiccants.
How Does VpCI Corrosion Protection Work?
VpCI works by conditioning the air inside an enclosed package. When metal components are wrapped in VpCI film or stored with VpCI emitters, the corrosion inhibiting compounds vaporise and disperse throughout the enclosed space. The vapour is attracted to metal surfaces, where it condenses into a molecular protective layer only a few molecules thick.
This layer works in three ways:
- It passivates the metal surface, interrupting the electrochemical reaction between metal, moisture and oxygen that produces corrosion.
- It reaches hidden areas that sprays and greases cannot: internal bores, threads, crevices, weld seams and assembled cavities.
- It self-replenishes inside the sealed package. If the layer is disturbed, fresh vapour redeposits protection automatically.
Because the protective layer is vapour deposited rather than applied by hand, coverage does not depend on an applicator reaching every surface. That makes VpCI particularly reliable for complex assemblies, machined components and equipment with internal cavities.
Why Does Equipment Corrode Faster Near the WA Coast?
Metal stored around Perth and near WA port precincts such as Fremantle and Kwinana faces two corrosion accelerants at once: humidity and airborne salt. Moist coastal air provides the water that corrosion chemistry needs, while salt particles carried on sea breezes deposit chlorides on metal surfaces. Chlorides are aggressive corrosion catalysts that break down protective oxide layers and dramatically increase rusting rates on unprotected steel.
Daily temperature swings make things worse. When warm humid air cools overnight, moisture condenses directly onto metal surfaces, including surfaces inside loosely covered packaging. Equipment staged at port laydowns awaiting export, or stored in coastal warehouses and yards, can begin corroding within weeks. Sealed VpCI packaging addresses both problems: the enclosure keeps salt-laden air away from the metal, and the inhibitor vapour neutralises corrosion at any moisture that does remain inside.
Which VpCI Products Are Used for Long-Term Equipment Storage?
VpCI is a technology delivered in several product formats. Most long-term storage applications combine two or more of the following:
VpCI Films
VpCI films are the workhorse of corrosion protection packaging. Available as sheeting, bags, tubing and shrink film, they wrap or fully enclose components while continuously releasing inhibitor vapour. Films provide multimetal protection for steel, aluminium, copper, brass and other metals, are transparent for easy identification, and are recyclable. Heavy duty options such as MilCorr shrink film are designed for demanding long-term outdoor preservation.
VpCI Emitters and Foams
VpCI emitters are compact devices placed inside enclosed spaces such as electrical cabinets, control panels, junction boxes and sealed cases. They continuously release inhibitor vapour to protect sensitive components and hard to reach internals where films cannot be applied.
VpCI Sprays and Coatings
VpCI sprays and coatings are applied directly to exposed metal surfaces that cannot be fully enclosed, or that need extra protection at the surface itself. Long-term outdoor protection coatings suit equipment stored in the open or in partially exposed conditions.
VpCI Desiccants
VpCI desiccants combine moisture absorption with corrosion inhibition. Placed inside sealed packaging, they pull humidity out of the enclosed air while the VpCI component protects the metal, a valuable combination for sea freight and humid coastal storage.
How Long Does VpCI Protection Last?
Inside intact sealed packaging, VpCI protection is long lasting and continuous, with heavy duty preservation films engineered for multi-year protection. The key variable is the integrity of the enclosure: as long as the package remains sealed, the inhibitor vapour keeps working and redeposits protection whenever surfaces are disturbed. Protection duration should always be matched to the storage plan, film specification and site conditions, which is why AXIS Industrial assesses each application before recommending a preservation system.
Is VpCI Better Than Oils and Traditional Rust Preventatives?
For most storage and export applications, yes. Traditional rust prevention relies on coating every surface with oil or grease, which is labour intensive to apply, misses internal cavities, attracts dust, and must be cleaned off before the equipment can be commissioned. VpCI packaging protects exposed and hidden surfaces alike, requires no surface preparation beyond clean dry metal, and leaves nothing to remove: unwrap the component and it is ready to install. That reduces both preservation labour at pack-up and recommissioning time at the other end, while also reducing the need for solvents and degreasers.
How Do You Package Equipment with VpCI for Long-Term Storage?
A typical VpCI preservation process for equipment going into long-term storage looks like this:
- Clean and dry the equipment. Corrosion inhibitors protect metal; they do not remove existing rust or contamination. Surfaces should be clean and dry before packaging.
- Place emitters in enclosed spaces. Cabinets, panels and internal voids get VpCI emitters or foam pads sized to the enclosure volume.
- Apply coatings to high-risk exposed surfaces. Machined faces, flanges and bare steel receive VpCI sprays or coatings where extra surface protection is warranted.
- Wrap or enclose in VpCI film. The asset is wrapped, bagged or shrink wrapped in VpCI film to create the sealed protective environment.
- Add desiccants and seal. VpCI desiccants control internal humidity, and the package is sealed, ready for storage, road transport or export.
For oversized assets, this process can be delivered on site through AXIS Industrial’s mobile preservation and heat shrink wrapping services, so equipment never needs to leave your yard to be protected.
Let’s Build Your Solution
From remote mine sites to metropolitan warehouses, AXIS Industrial supplies the full VpCI preservation range across Perth and Western Australia, backed by mobile application services and export packaging expertise. Whether you are storing critical spares near the coast, preserving equipment between projects, or preparing machinery for export, the right VpCI system keeps your metal assets in ready-to-run condition.
Get a free measure and quote today at axisindustrial.com.au/contact or call +618 9353 1313 to chat with our experts. No obligation, no pressure.
