Water-Based Rust Preventative, Paintable Dry Film – 55 Gallon Drum (Cortec® VpCI®-379)

Description

VpCI®-379 is a water-based rust preventative concentrate that leaves a clear dry film for sheltered indoor storage. The useful part: it can be painted over without being removed first. The 55-gallon drum is the size for a production dip tank or a parts-washer rinse stage feeding the paint line.

VpCI-379 is Cortec’s water-based replacement for oil-based rust preventatives on parts that are headed for paint. The dry film accepts paints and primers directly, so the storage coating and the pretreatment step stop fighting each other. Dilution sets the protection period: 1:1 to 1:5 for up to two years, 1:6 to 1:10 for medium-term storage, and 1:10 to 1:20 for short-term in-process protection. The brochure positions it for long-term indoor storage and shipping, it carries NSN 8030-01-481-8928 and is used by military customers. In the Cortec Product Consultation Guide it is rated 2 (inside storage) on carbon steel, stainless steel, cast iron, aluminum alloys, galvanized steel, copper, brass and solder. It is not for direct outdoor exposure; packaged items must be kept out of the rain.

Typical applications

• Castings, forgings, machined components
• Gears, pumps, motors
• Structural steel and precision parts
• Packaged items not exposed to rain
• Additive to parts washers and rinse systems
• Fabrications and weldments awaiting the paint line
• Engine and drivetrain components in indoor storage
• Indoor parts protection for automotive and heavy-equipment tier suppliers
• Military and defense parts stored to an NSN specification

How to apply VpCI-379

1. Surface preparation. Clean, dry metal free of grease, oil, rust and soils, the SSPC-SP-1 condition Cortec specifies for its water-based rust preventatives. Parts coming through a washer on a VpCI-41x cleaner are ready as they are.
2. Dilution. Dilute with water anywhere from 5 to 50 % by volume, choosing the ratio from the table below and mixing with light agitation.

3. Dilution (VpCI-379 : water)	Protection period
   1:1 to 1:5	Up to 2 years indoors
   1:6 to 1:10	Medium term
   1:10 to 1:20	Short term, in-process

4. Method. Dip, spray, or dose the final rinse of a parts washer or rinse system. Cover every critical surface, including recesses and blind holes.
5. Drying. The film is dry to the touch within 30 minutes at ambient conditions. Let parts dry fully before stacking or packaging.
6. Painting. Paints and primers can be applied over the dry film without removal.
7. Removal. When the film must come off, use a conventional alkaline cleaner such as VpCI-414, 416 or 418LM, which also protects against flash rust.
8. Bath control. Cortec does not publish a refractometer chart for VpCI-379, so build one: take Brix readings of your own dilutions at, above and below the target and plot them (the method is on our refractometer and pH charts for every Cortec product page). Top up with fresh solution as the bath drifts.
9. Storage and shelf life. Two years in the original sealed container.

Where it fits in the Cortec line

Choose VpCI-379 over VpCI-377 when the part will be painted: both are water-based, dilutable, indoor-rated multi-metal concentrates, but the 379 film is the one specified to take paints and primers directly. BioCorr is the ready-to-use biobased option, VpCI-316 handles copper and brass, and for parts that must sit outside move to a removable coating such as VpCI-389 or the oil-based VpCI-369. Like VpCI-377, VpCI-379 runs as a rinse-stage additive in Build-All and Magido aqueous parts washers, so the washer delivers a clean, protected, paint-ready part in one cycle. Browse the full Cortec VpCI line.

Field notes

An Indiana locomotive-engine plant had test water leaving new cooling systems rusting in outdoor storage between build stages, and the residual water had to be freeze-proof. A mix of 20% VpCI-379, 20% glycol and 60% water is circulated, captured, tested and reused; VpCI-379 has been in the company specification since 1999. (Cortec Case History #623)

A Moline, Illinois tractor plant had hydraulic components rusting in the few days between machining and assembly, and its oil dip tank was messy. A dip in VpCI-379 at 1:10 with water replaced the oil dip with odorless, cleaner interim protection. (Cortec Case History #037)

A Sycamore, Illinois blade maker’s solvent-based inhibiting oil dripped and forced repackaging. VpCI-379 at 1:10 in the final rinse water, parts then dried, gave consistent protection, fewer process steps and clean, dry parts. (Cortec Case History #036)

A Lafayette, Indiana engine plant found new engines rusting in the cooling jacket after hot test. A 1,500-gallon station of 20% VpCI-379 in water now flushes the jacket after the test coolant is drained, and the blocks stay rust-free to destination. (Cortec Case History #125)

Specifications

Dilution and duration	1:1–5 up to 2 years; 1:6–10 medium term; 1:10–20 short term
Dilution range	5% to 50% in water
Dry to touch	Within 30 minutes at ambient
Humidity (ASTM D1748)	300+ hours at 5% in water
Removal	Removable with conventional alkaline cleaners, and can be coated over with paints and primers without removal
Limitation	Not for direct outdoor exposure
Film	Clear, dry, paintable
Appearance	Clear amber liquid
pH (concentrate)	8.6–9.7
Non-volatile content	28–35%
Density	8.5–8.8 lb/gal (1.01–1.05 kg/L)
Application	Dip, spray, or additive to parts washers and rinse systems
Metals	Carbon steel, stainless steel, cast iron, aluminum, galvanized steel, copper, brass, solder
Consultation guide rating	2 – inside storage
Standards	NSN 8030-01-481-8928
Storage	Original packaging, indoors, out of direct sunlight, 40–100 °F (4–38 °C)
Shelf life	2 years
Size	55 Gallon Drum
Shipping weight	491 lb (223 kg)
Availability	In stock
Cortec product number	12000101

Solvent Recycling Systems is an authorized Cortec® distributor. See the full Cortec VpCI line, browse the VpCI product selection guide, or contact us for volume pricing and lead times.