Every vessel on the Great Lakes and the inland rivers spends part of the year idle, and a ship, tug, ferry or workboat that is idle in cold, wet, salt-treated air is corroding faster than one that is working. Cortec publishes a system-by-system layup procedure for ships that uses its VpCI® vapor phase corrosion inhibitors to protect engines, fuel and oil systems, cooling water, electrical gear, deck machinery, voids and the superstructure through a winter layup, a cold stack or a multi-year preservation. This page restates that procedure as a working checklist for vessel operators, shipyards, marine engine dealers and Coast Guard and federal buyers, with Cortec’s published dose for each step and a link to the Solvent Recycling Systems listing where we stock the product. Steps that call for a product we do not carry as a stock item are marked “available to order.” For aircraft, the companion page is aircraft layup and long-term storage; for choosing a VpCI product by metal and environment, see the VpCI product selection guide.
Why vessels corrode in layup
Cortec’s summary applies to any idle asset: moist, salt-laden air and fluctuating humidity condense on electrical systems, rotating equipment, hydraulics, bolts, valves and motors, and the bill comes due as premature failure, unplanned repair and delay at fit-out. On a laid-up vessel the problem is worse than on shore equipment for three reasons. The hull is a steel box sitting in water, so the internal air is always near saturation and every void, double bottom and cofferdam sweats when the temperature drops. Engine rooms, pump rooms and machinery spaces are full of mixed metals (cast iron blocks, steel shafting, bronze bearings and impellers, copper piping, aluminum housings) that form galvanic couples the moment condensate bridges them. And a working vessel is preserved in a hurry at the end of the season and put back in a hurry at the start of the next, so anything that has to be scraped or steam-cleaned off in April is a cost most operators will not pay.
The conventional answer, filling every system with preservative oil, greasing every exposed surface and running dehumidifiers all winter, works and is expensive to undo. Cortec’s procedure replaces most of it with vapor-phase products: pouches and emitters in closed spaces, a fogged inhibitor in engine and turbine flow paths, and additives in the oil, fuel and cooling water that stay in the system when the vessel returns to service. Contact products (temporary coatings, greases, permanent coatings) are reserved for surfaces that sit in the weather.
Before you start: clean, de-rust, then protect
Nearly every line in Cortec’s ship procedure begins the same way: remove rust, wash, then protect. The rust remover is VpCI-423, a biobased gel that clings to vertical surfaces, or VpCI-422 liquid for parts that can be dipped; neither is for aluminum, where VpCI-426 or VpCI-429 is used instead. The wash is VpCI-415 at 10 percent by volume, a biodegradable cleaner that leaves a flash-rust inhibitor behind so the surface stays clean until the next step. Where a pressure washer cannot be used near electrical gear, Corwipe 500 wipes and VpCI-414 aerosol do the same job by hand. For heavy scale on hull plate, deck fittings or spares that are going to be repainted, chemical de-rusting is slow; an abrasive blast room brings the steel to the SSPC profile the permanent coatings below call for, and a Build-All or Magido aqueous parts washer handles the pumps, valves, injectors and small machinery that come off the vessel for the winter.
The procedure zone by zone
The order follows Cortec’s published ship procedure. Doses are Cortec’s figures from the same page; where the current product data sheet gives a different or wider range, the note says so. Confirm every dose against the data sheet shipped with the product, and where the engine or equipment maker publishes a layup procedure, that procedure governs.
Zone 1: Main and auxiliary engines
| Step | Product | Dose or method | SRS listing |
|---|---|---|---|
| Clean the engine exterior and remove rust | VpCI-415, then VpCI-423 | 415 at 10 percent; 423 gel on rusted areas, rinse | VpCI-415, VpCI-423 |
| Add a VpCI to the engine lube oil and run the engine to circulate | M-531 | 5 percent by volume in the oil (data sheet typical range 3 to 5 percent); Cortec Case History #701 used 3 percent | M-531; M-529 is the alternative package used in the landing-craft field note below |
| Fog the turbocharger and air path | M-531 (fogged) or VpCI-337 | M-531 fogged at 0.5 oz/ft³ per Cortec’s chart (data sheet says 1 oz/ft³); VpCI-337 at 0.5 oz/ft³ | M-531, VpCI-337 |
| Coat exhaust manifolds and other high-temperature sections | VpCI-371 | Silicone DTM coating rated to 1200 degrees F; brush or spray on clean metal | VpCI-371 |
| Spray exposed shafting, couplings and linkages | VpCI-369 D or CorShield 369 | Thin oily film; ready to use | VpCI-369 D, CorShield 369 aerosol |
| Gearboxes and reduction gears | M-531 | Add at 5 percent to the gear oil, or fog the case | M-531 |
| Hydraulic systems (steering, deck cranes, hatch covers) | VpCI-322 or M-531 | VpCI-322 is the additive used in hydraulics in the landing-craft field note; M-531 data sheet lists hydraulic use | VpCI-322 |
The point of running the engine after dosing is to get the treated oil onto every bearing, cylinder wall and cam lobe before shutdown. The oil additive then protects by contact where the oil film is and by vapor in the crankcase air above it. Cortec’s landing-craft field notes (#587 and #588) ran the engines about 20 minutes after treating fuel, oil, coolant and hydraulics. Check the oil-additive compatibility table on the compatibility charts page before dosing a synthetic or an oil with an unusual additive package, and where the engine maker has an approved product list, use it; the OEM approvals section below lists what Cortec has published.
Zone 2: Fuel tanks and fuel systems
| Step | Product | Dose or method | SRS listing |
|---|---|---|---|
| Treat diesel day tanks, service tanks and bunkers | VpCI-705 | 0.1 to 0.15 percent of tank volume; circulate or run the engine so treated fuel reaches injectors and lines. Case History #575 dosed at 100 ppm. | VpCI-705 |
| Fog an empty fuel tank | VpCI-705 | 1.5 oz per 10 gallons of tank volume, fogged to cover the internal surface | VpCI-705 |
| Cortec’s ship procedure product for fuel storage tanks | VpCI-707 | 0.2 percent by volume | Available to order |
VpCI-705 also stabilizes the fuel and protects rubber seals and gaskets against oxidation, which matters for a boat whose fuel will sit for six months. Cortec’s ship page names VpCI-707 for fuel storage tanks; the field notes on working vessels used VpCI-705 or VpCI-706, and we stock 705.
Zone 3: Cooling water, ballast and hydrotest water
| Step | Product | Dose or method | SRS listing |
|---|---|---|---|
| Closed-loop jacket water and freshwater cooling | M-640L (engines) or VpCI-649 (closed loops) | M-640L at 3 percent by volume; VpCI-649 at 0.5 percent by volume; circulate, then leave full or drain | Available to order |
| Seawater-side raw-water systems | VpCI-645 | 75 percent by volume per Cortec’s chart (Case History #575 used 0.75 percent in seawater flushes; confirm the dose with Cortec for your system) | Available to order |
| Wet layup of a cooling system with a stocked product | VpCI-377 | Case History #622 used VpCI-377 at 20 percent in cooling water, cycled through, drained and recaptured, for two years of outdoor storage of locomotive engines | VpCI-377 |
| Hydrotest water for boilers, coolers and piping going into layup | VpCI-609 | 4 to 8 percent in the test water per the data sheet; leave a wetted film, or drain and leave the residue | VpCI-609 |
| Ballast tanks (cleaning) | ECO-CLEAN-ALL | Hard-surface cleaner | Available to order |
| Empty ballast tanks, double bottoms and voids | VpCI-609 (ferrous only) or VpCI-308 (mixed metals) | Fog powder at 0.5 oz/ft³ (data sheet range 0.3 to 0.5 oz/ft³), or one VpCI-308 pouch per 35 ft³ | VpCI-609 S, VpCI-308 pouches |
VpCI-609 carries Cortec’s explicit caution against copper and copper alloys, so it belongs in steel-only spaces: ballast tanks, double bottoms, rudder cavities, chain lockers. Where the space has bronze fittings or copper piping, use the VpCI-308 pouch or fog VpCI-337 instead. VpCI-609 S, the version with a silica flow agent, is the grade Cortec’s drill-ship and cold-stack field notes fogged into bulk tanks. If you hydrotest a boiler or heat exchanger before layup, dissolve VpCI-609 in the test water and the residue protects the system after draining; the concentration testing page gives the refractometer method for checking the solution before the test.
Zone 4: Generators, motors and electrical
| Step | Product | Dose or method | SRS listing |
|---|---|---|---|
| Spray switchboard contacts, terminal strips, relays and connectors | ElectriCorr VpCI-239 | Very light mist; dries in 1 to 2 hours at 70 degrees F; heavy mist sags | VpCI-239 aerosol, bulk pail; VpCI-238 for bridge electronics and monitors |
| Fog generator and motor windings and cores | ElectriCorr VpCI-239 | Light fog through the air inlets; do not soak | as above |
| Install an emitter in every panel, cabinet, junction box and motor terminal box | VpCI-101, VpCI-105, VpCI-111, VpCI-308 pouch | One VpCI-101 per 1 ft³; VpCI-105 per 5 ft³; VpCI-111 per 11 ft³ (Cortec’s chart rounds to 10); VpCI-308 pouch per 35 ft³. Rated up to 24 months closed. | VpCI-101, VpCI-111, VpCI-308; VpCI-105 available to order |
| Generator engine oil | M-531 | 5 percent in the oil, as for the main engine | M-531 |
| Bridge consoles, radar and radio racks, monitors | VpCI-105 or VpCI-111 plus Corwipe 500, then Cor-Pak VpCI stretch film over the console | Wipe, place the emitter, wrap | Corwipe 500, Cor-Pak stretch film |
| Engine room, wheelhouse and large machinery spaces | VpCI-137 foam or VpCI-132 pads | Foam roll hung through the space, sized by enclosure volume | VpCI-137 foam roll, VpCI-132 pads |
The emitters carry the electrical side of the layup. Cortec’s data sheets say they do not interfere with electrical, optical or mechanical performance, VpCI-101 and VpCI-111 are used on marine navigation and communication equipment, and VpCI-111 is accepted for U.S. military and NATO use, with NSNs on all three sizes. Date every emitter and log it; if a panel is opened often during the winter, replace its emitter sooner than the 24-month rating.
Zone 5: Deck machinery, winches, cranes and wire rope
| Step | Product | Dose or method | SRS listing |
|---|---|---|---|
| Winches, hoists, windlass, capstan drums and gears | VpCI-369 D | Spray a thin oily film over gears, drums, brake bands and exposed shafts | VpCI-369 D |
| Wire rope, towing hawsers and crane cable | VpCI-369 D or EcoLine Wire Rope Grease | Run the rope through a brush or spray as it spools; Case History #575 used CorrLube on bearings and wire rope | VpCI-369 D; wire rope grease available to order |
| Grease every zerk fitting, sheave and bearing | CorrLube VpCI Lithium EP Grease | Grease-gun until clean grease shows | CorrLube pail, cartridges |
| Valve stems, packing nuts and seized hardware | VpCI Super Penetrant, then VpCI-369 D on the stem | Penetrant on bushings and packing body nuts; 369 D on the stem | Super Penetrant available to order (EcoLine ELP stocked); VpCI-369 D |
| Bare-metal bolting, flanges, rails and crane structure in the weather | VpCI-368 D or VpCI-368 | Waxy dry film rated by Cortec for up to 2 years outdoors; removable with alkaline cleaner or solvent | VpCI-368 D, VpCI-368, CorShield 368 aerosol |
| Shroud deck machinery, cranes and junction boxes that stay on deck | MilCorr VpCI shrink film with shrink tape | Frame, wrap, heat-shrink, tape the seams; pad edges with VpCI-132 or VpCI-137 foam so the film does not chafe through | MilCorr 20 x 210, MilCorr 20 x 100, shrink tape |
Deck machinery is where the two approaches meet: a contact coating on the steel and a shroud that keeps rain and spray off it. Cortec’s ROV support vessel, drill-ship and frigate field notes all wrapped deck machinery in MilCorr with foam padding at the corners; the sizing, seaming and heat-shrinking method is on the MilCorr shrink-wrap guide. For a small craft, the same film goes over a frame across the whole boat; a Minnesota owner in Case History #251 has re-wrapped a yacht in MilCorr every winter and found it rust-free each spring.
Zone 6: Exterior, hull, decks and superstructure
| Step | Product | Dose or method | SRS listing |
|---|---|---|---|
| Guard rails and handrails | VpCI-423, VpCI-415, then EcoShield 386 | De-rust, wash, one or two coats of the clear or colored water-based acrylic | EcoShield 386; colored VpCI-386 grades |
| Decks, bulkheads and hull plate that will be recoated | VpCI-423, VpCI-415, two coats VpCI-395, topcoat VpCI-384 | Blast or de-rust to the profile the primer calls for, wash, prime, topcoat | VpCI-395 Part A and Part B; VpCI-384 available to order, or topcoat with VpCI-386 |
| Deck plates and grating | VpCI-423, VpCI-415, then VpCI-396 (or CorrVerter where rust cannot be removed) | One-coat moisture-cure urethane; CorrVerter converts residual rust and primes in one coat | VpCI-396, CorrVerter |
| Exposed machined aluminum and stainless (shaft ends, fittings, bright work) | VpCI-423, VpCI-415 at 10 percent, then VpCI-391 clear | Non-tacky clear water-based temporary coating; removable with VpCI-414 | VpCI-391 |
| Wheelhouse exterior and painted superstructure (temporary) | VpCI-389 D | Goes on white, dries clear; washes off with VpCI-414 at fit-out | VpCI-389 D |
| Severe marine service, bare steel that will stay in the weather | EcoLine 3690 | Biobased outdoor coating; brush, roll or spray | EcoLine 3690 |
| Piping and equipment under insulation | VpCI-658 | Injected into the insulation to control corrosion under insulation | Available to order |
Two of these lines are permanent coatings, not layup products, and Cortec’s ship page treats a layup as the moment to do the repaint. VpCI-395 is a two-part water-based epoxy primer and VpCI-396 a moisture-cure urethane, and both need a proper surface profile, which is the blast-room step above. Film builds, recoat windows and application conditions for all of them are on the Cortec coatings application guides page.
Zone 7: Accommodation, galley, sanitary and boilers
| Step | Product | Dose or method | SRS listing |
|---|---|---|---|
| Cabins, mess, galley, passageways and stores | VpCI-308 pouch or VpCI-137 foam | One pouch per 35 ft³ of closed space, evenly spaced; foam sized by volume in large rooms | VpCI-308, VpCI-137 |
| Spaces that will be sealed and not entered | Desicorr VpCI | Desiccant plus VpCI pouch; one 1-unit pouch per 5 ft³ | Desicorr NW VpCI |
| Toilets and holding tanks | ECO-SEPT, PORTA-TREAT 10X | Additive per label | Available to order |
| Hot-water and heating boilers, wet layup | VpCI-649 (non-potable hot water) or M-640L (closed loop) | 649 at 0.5 percent; M-640L at 3 percent in feed and condensate; circulate, then leave full or drain | Available to order |
| Boilers, dry layup | Boiler Lizard (water side), Boiler Dragon or Gecko (fogged, water and fire sides) | One Lizard tube per 1,000 gallons; Dragon and Gecko at 0.5 oz/ft³ | Available to order; VpCI-609 hydrotest powder and VpCI-308 pouches are the stocked alternatives for the water side |
| Steam lines and steam turbines | Boiler Dragon in the lines; VpCI-337 fogged into the turbine steam path; M-531 in the bearing oil | 0.5 oz/ft³ for both fogged products | VpCI-337, M-531; Boiler Dragon available to order |
Return to service
Work the zones in reverse and keep the layup log next to you.
- Collect the emitters, pouches, foam and desiccant from every panel, cabin and void, checking each date label against the log so none is left behind in a junction box.
- Cut the shrink film off deck machinery and fold it for disposal as polyethylene. Cortec’s data says the equipment is ready to use on removal.
- Fogged spaces. VpCI-337 and VpCI-609 usually do not need to be removed; Cortec’s data sheet says a low-pressure air gun or a water rinse clears any 609 residue if the equipment maker requires it, and recommends reviewing turbine flow-path applications with its technical service before commissioning.
- Additives. M-531, M-529, VpCI-322 and VpCI-705 stay in the oil, hydraulic fluid and fuel and are consumed or changed on the normal schedule. Cooling-water inhibitors are drained and, in the VpCI-377 field note, recaptured, tested for concentration and reused.
- VpCI-369 D and CorrLube stay on; they are lubricants.
- VpCI-368 D, VpCI-391 and VpCI-389 D come off with VpCI-414 at the dilution on its data sheet; the waxy 368 film also comes off with mineral spirits. Dwell times and removal notes are on the coatings application guides.
- Permanent coatings (386, 395, 396, CorrVerter, EcoLine 3690) stay.
OEM approvals
Cortec publishes the following marine and turbine OEM approvals for products in this procedure: Caterpillar (VpCI-377, VpCI-391); GE Marine engines (VpCI-377); GE gas turbines (M-531, VpCI-337, VpCI-391, VpCI Super Penetrant, VpCI-377, VpCI-386 HT); Wärtsilä (VpCI film, BioPad, VpCI-322, VpCI-649, VpCI-645, VpCI powders and cleaners); Rolls-Royce (VpCI-126 bags); and Fincantieri shipyard (VpCI-609, VpCI-645). Of those, Solvent Recycling Systems stocks VpCI-377, VpCI-391, M-531, VpCI-337, VpCI-386, BioPad, VpCI-322, VpCI-126 bags and VpCI-609. Where an approval is tied to a specific grade (386 HT, for example), confirm the grade with us before ordering against an OEM procedure.
Shopping list
| Product | Used in | Listing |
|---|---|---|
| VpCI-415 cleaner | Every wash step | 5 gallon, 55 gallon |
| VpCI-423 gel / VpCI-422 liquid | Rust removal | VpCI-423, VpCI-422 |
| M-531 | Engine, gearbox, generator and turbine oil; fogging | 5 gallon, 55 gallon |
| M-529 / VpCI-322 / M-535 | Alternative oil packages; hydraulics; turbine and compressor oils | M-529, VpCI-322, M-535 |
| VpCI-705 | Diesel and gasoline tanks | 5 gallon, 55 gallon |
| VpCI-337 | Turbochargers, pumps, compressors, turbine steam paths, mixed-metal voids | 5 gallon, 55 gallon, EcoAir 337 aerosol |
| VpCI-609 / VpCI-609 S | Hydrotest water, ballast tanks, steel voids | VpCI-609 5 lb, 50 lb, VpCI-609 S |
| VpCI-377 | Cooling-water wet layup (field note) | 5 gallon |
| VpCI-308 pouch | Accommodation, mixed-metal voids, panels | 50 per drum |
| VpCI-101 / VpCI-111 emitters | Panels, junction boxes, terminal boxes | VpCI-101, VpCI-111; VpCI-105 available to order |
| VpCI-137 foam / VpCI-132 pads / BioPad | Machinery spaces, wheelhouse, padding under film | VpCI-137, VpCI-132, BioPad |
| ElectriCorr VpCI-239 / VpCI-238 | Contacts, windings, bridge electronics | VpCI-239, VpCI-238 |
| Desicorr NW VpCI | Sealed spaces, shaft cavities | 1 unit |
| VpCI-369 D / CorShield 369 | Shafting, winches, wire rope, valve stems | 5 gallon, aerosol |
| VpCI-368 D / VpCI-368 / VpCI-368 M | Bare bolting, flanges, rails in the weather; MIL-PRF-16173E Grade 1 work | 368 D, 368, 368 M |
| VpCI-391 / VpCI-389 D | Clear temporary coatings for aluminum, stainless and painted superstructure | VpCI-391, VpCI-389 D |
| VpCI-371 | Exhaust manifolds, high-temperature sections | 5 gallon |
| EcoShield 386 / VpCI-386 / VpCI-395 / VpCI-396 / CorrVerter / EcoLine 3690 | Permanent coatings for rails, decks, hull, grating | EcoShield 386, VpCI-386, VpCI-395, VpCI-396, CorrVerter, EcoLine 3690 |
| CorrLube VpCI Lithium EP Grease | Zerks, sheaves, bearings, wire rope | 5 gallon, cartridges |
| MilCorr shrink film and tape; VpCI-126 Blue bags | Deck machinery shrouds; indoor and sheltered wrapping | MilCorr 20 x 210, 20 x 100, tape, VpCI-126 gusseted bags |
| Corwipe 500 / VpCI-414 | Hand cleaning near electrical gear; coating removal at fit-out | Corwipe 500, VpCI-414 |
| VpCI-707, VpCI-649, VpCI-645, M-640L, VpCI-384, VpCI-658, Boiler Lizard / Dragon / Gecko, EcoLine Wire Rope Grease, Super Penetrant, ECO-SEPT, PORTA-TREAT, ECO-CLEAN-ALL | Fuel storage, cooling water, boilers, CUI, wire rope, sanitary | Available to order |
Field notes from Cortec case histories
Drawn from Cortec’s published case history library and retold in our words; customer names are omitted.
- Cortec Case History #729. A Milwaukee machine shop had to preserve a large spare marine engine crankshaft for up to ten years. The shaft was cleaned with mineral spirits, VpCI-369 brushed into every surface and oil hole, then laid in a long metal box lined with 10 mil VpCI-126 HP UV film with a second sheet and foam pad over the wood bracing, BioPads placed throughout, and the film wrapped and heat-shrink-taped with the upper sheet overlapping the lower as a watershed. It shipped to an East Coast dealer fit for indoor or outdoor storage for years. Any marine engine dealer holding spare cranks, camshafts or liners can copy this with stocked VpCI-369, BioPad and MilCorr film.
- Cortec Case History #701. A large ROV support vessel sat idle for eight months waiting for a contract. Bridge consoles, junction boxes, motors and monitors got VpCI-105 emitters, Corwipe cleaning, VpCI-238 and a Cor-Pak stretch-film wrap; the machinery control room and switchboard got desiccant plus VpCI-105; deck machinery was shrouded in MilCorr with shrink tape; the bridge top and boat deck were rinsed with VpCI-414 and coated with VpCI-368 over CorrVerter where needed; the main engines were rinsed with 414 and dosed with M-531 at 3 percent by volume; VpCI-706 went in the fuel; CorShield 369 on shafts and CorrLube where grease was needed. Low-cost storage and quick redeployment.
- Cortec Case Histories #587 and #588. A naval support yard in England stored three landing craft outdoors on land for about six months, and a fourth for up to five years, all needing rapid return to service. The fluid recipe was VpCI-705 in fuel, M-529 in engine and gearbox oil, M-640 L in coolant and VpCI-322 in hydraulics, then the engines were run about 20 minutes. VpCI-101 and 105 went in junction boxes, VpCI-137 foam in the engine compartment, well and wheelhouse, VpCI-368 on bare metal, VpCI-369 on ramp rams, VpCI-368 D on deck and VpCI-389 D on the wheelhouse exterior. The five-year craft had its engines removed for separate storage and the whole craft shrink-wrapped in MilCorr with a zip door.
- Cortec Case History #585. A frigate entering layup before refit had its outer-deck equipment padded with VpCI-132 foam and MilCorr-shrunk, davits and winch motors sprayed with VpCI-369, seized parts treated with Super Penetrant, external electric boxes fitted with VpCI-101 and 105, cable ends bagged in VpCI-126, and walkways washed with VpCI-415 and coated with VpCI-389 D. Practical layup, easy removal, no monitoring.
- Cortec Case History #517. A drill ship in hot layup (engines live, rig idle) had risers fogged with VpCI-337 and end-capped with VpCI-126 HP UV, bulk and cement tanks treated with VpCI-609 S, junction boxes, motors and monitors fitted with 101/105/111 emitters or VpCI-170 tape, in-service oil systems dosed with M-529 and empty ones with VpCI-322, pistons coated with VpCI-369 D, rails and cranes with VpCI-368 D, and rust that could not be removed converted with CorrVerter.
- Cortec Case History #563. An LNG carrier operator’s spare intermediate shafts, bearings, couplings and fasteners were de-rusted with VpCI-422, washed with 5 percent VpCI-414, coated with VpCI-368 and 369, fitted with Desicorr in the shaft cavities, padded with VpCI-137 foam on corners and edges, and MilCorr-shrunk. Re-opened at three months with no dirt or corrosion.
- Cortec Case History #622. A locomotive engine builder protected engine cooling systems for two years of outdoor storage with VpCI-377 at 20 percent in the cooling water, cycled through, drained and recaptured; the recaptured solution was tested for concentration and reused, and the program was in its ninth year when written up.
- Cortec Case History #251. A Minnesota yacht owner frames the deck each fall, pulls MilCorr over it, ties it at the hull and heat-shrinks it around the straps; the boat is rust-free each spring and the owner re-wraps annually.
Frequently asked questions
How long does a VpCI layup last on a vessel?
Cortec’s ship procedure does not state a duration; the product data sheets do. Emitters, VpCI-308 pouches and VpCI-609 are rated for up to 24 months in a closed space; VpCI-368 D for up to 2 years outdoors; MilCorr for multi-year outdoor exposure. The field notes above cover eight months (ROV vessel), six months and five years (landing craft), and ten years (crankshaft). Plan emitter and pouch replacement at 24 months on a long layup, as the five-year refrigeration-plant field note (#589) did at year two.
Do I still need dehumidifiers in the engine room?
VpCI protects the metal in spite of humidity rather than removing it, so a dehumidifier is not required for the inhibitor to work. Where you already run one, keep it; the two are complementary. In spaces that will be sealed and left, Desicorr VpCI pouches give both moisture control and inhibitor.
Nitrogen blanket or VpCI for tanks and pipework?
Nitrogen protects only while the seal holds, and inspections break it. Cortec has published comparisons of VpCI-337 against nitrogen and dry-air blanketing, and its refinery case history (#519) records a nitrogen purge that failed early on idle equipment and was replaced with VpCI fogging. A fogged inhibitor layer survives an opened manway and re-forms when it is closed.
What is the engine oil additive dose, and does it hurt the oil?
Cortec’s ship procedure gives M-531 at 5 percent by volume in lube oil; the data sheet’s typical range is 3 to 5 percent and one field note used 3 percent. M-531 is a lubricant additive package that passes the ASTM D665 turbine oil rust test and the D130 copper strip test, and it stays in the oil until the next change. Verify solubility and compatibility with your oil on the compatibility charts and, for a fleet, with Cortec technical service.
Is it safe on bridge electronics and switchboards?
The emitters are designed for it. Cortec’s data sheets list marine navigation and communication equipment as a typical application for VpCI-101, 105 and 111, say they do not interfere with electrical, optical or mechanical performance, and VpCI-111 is accepted for U.S. military and NATO use. Use VpCI-238 rather than 239 on sensitive indoor electronics and keep any spray to a light mist.
What has to be removed at fit-out?
Emitters, pouches, foam, desiccant, covers and shrink film come out or off. VpCI-368 D, VpCI-391 and VpCI-389 D are washed off with VpCI-414. Oil, fuel and hydraulic additives, VpCI-369 D on moving parts, CorrLube grease and the permanent coatings stay. Fogged VpCI-337 and VpCI-609 usually stay too, subject to the equipment maker’s requirements.
Can I use VpCI-609 in a tank with bronze fittings?
No. Cortec’s data sheet says not to use VpCI-609 on copper, copper alloys or other soft metals. Use VpCI-308 pouches or fog VpCI-337 in mixed-metal spaces and keep 609 for steel-only ballast tanks, voids and hydrotest water.
We do a winter repaint. Where do the coatings fit?
Cortec’s ship procedure treats rails, decks, hull plate and grating as repaint items: de-rust with VpCI-423, wash with VpCI-415, then EcoShield 386, VpCI-395 plus topcoat, or VpCI-396 (CorrVerter where rust cannot be fully removed). The primers need a blast profile, which is where a blast room earns its keep on a yard. Application details are on the coatings application guides.
Solvent Recycling Systems is an authorized Cortec® distributor serving Great Lakes and inland-river operators, shipyards, marine engine dealers and Coast Guard and federal customers. See the full Cortec VpCI line, browse the VpCI product selection guide, or contact us with the vessel type, the systems on board and the planned layup length for a sized quote.
Data source: compiled from Cortec’s published ship long-term storage procedure and dosage chart, current product data sheets and Cortec case histories; confirm every dose against the current product data sheet and the engine or equipment manufacturer’s layup instructions before specifying.
