CASE HISTORY SPOTLIGHT: Case History #735: Corrosion Preventative Maintenance on Fertilizer Loaders


Front-end loaders for moving high volumes of deicing salts and/or fertilizers at ports along the Ohio River had a habit of corroding quickly. The aggressive environment forced the company to search for a new preventative maintenance plan that would keep the equipment from looking 10 years old in just one year and reduce the normal replacement frequency of two to three years.

VpCI®-391 is now applied once a year during the slow season. The equipment is power washed and dried before receiving a complete overspray of VpCI®-391 on the front, back, top, and bottom—everything except the windows. The client loved the product and has been using it for more than a decade to extend equipment service life—no special permitting required for this low-VOC coating!

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Keywords: preventative maintenance, front-end loader maintenance, extend equipment service life, fertilizer corrosion, deicing salt corrosion, Cortec, VpCI, VpCI-391, low VOC coating, corrosion

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PRESS RELEASE: VpCI®-391: Inconspicuous Removable Coating Offers Convenient Corrosion Protection

VpCI-391 Tractor with front end loader scored feed for cows. View of the side on the background of bales with silage. Necessary equipment for a dairy farm.

Corrosion is an irreversible process that costs industries time and money to deal with the effects. Corrosion prevention is therefore in the best interest of manufacturers and asset owners responsible for covering losses from deteriorating assets. While protective VCI packaging solves many metal shipping and storage needs, it is not always the optimal choice for certain metal shapes or storage/transit settings. When this is the case, Cortec’s VpCI®-391 is an excellent removable coating to consider for temporary or even long-term corrosion protection.

Unnoticeable Dry Film Rust Preventative Coating

VpCI®-391 is a fast-drying water-based temporary coating that dries to a thin, clear, virtually unnoticeable non-tacky film. It is perfect for protecting bare metal surfaces from corrosion in transit or temporary storage but can also be applied directly over painted surfaces. VpCI®-391 provides protection indoors and outdoors and is easy to remove with an alkaline cleaner if desired. These features have made it a popular temporary rust preventative coating that displaces traditional greasy, oily rust preventatives with an unnoticeable temporary protective coating that is drastically more convenient.

Clean, Convenient Corrosion Protection

There are many advantages to using VpCI®-391. In addition to its corrosion protection, the dry, non-tacky surface finish stays much cleaner than traditional oily/greasy rust preventatives that tend to collect insects, dust, and other contaminants on their sticky surfaces. It also weathers much better in outdoor applications. Furthermore, testing has found that VpCI®-391 does not negatively impact weld geometry or mechanical properties of the weld, allowing welders to easily keep surfaces corrosion-free prior to welding without extensive surface-prep hassle.

When and Where to Use VpCI®-391

The possibilities for using VpCI®-391 are endless. Examples include the following:

  • Heavy Equipment
  • Machinery
  • Vehicles
  • Piping
  • Structural Steel

Transit is one period in which VpCI®-391 is beneficial for safeguarding brand-new metal components—whether fire trucks, valves, or front-end loaders—from unpredictable exposure to harsh weather conditions on land and sea. It can be sprayed over unpainted bolts and metal tubes as well as metal wheel rims or entire painted vehicles. Since VpCI®-391 is relatively unnoticeable, distributors often leave it on new equipment until resale.

VpCI®-391 is also great for storage and layup. For example, VpCI®-391 can be applied right over painted railings and equipment on offshore platforms for extra corrosion protection during rig-stacking. Pipeline segments stored in laydown yards may be coated with VpCI®-391 to protect weld ends from rusting. At the time of assembly or installation, the welder can simply clean off the coating or weld directly over it, instead of spending extra time grinding away opportunistic rust that could otherwise set in.

A third purpose for VpCI®-391 is preventative maintenance. For instance, one company that uses front-end loaders to move high volumes of deicing salts or fertilizers has adopted VpCI®-391 as part of their annual preventative maintenance routine. By applying VpCI®-391 over the vehicles once a year during the slow season, the equipment lasts longer and does not look 10 years old after just one year of use.

Effective, Easy, and Inconspicuous

Anyone who needs a dry temporary corrosion protection coating should consider VpCI®-391 as an easy, effective, versatile, and inconspicuous option. It looks good and performs well even in outdoor environments, allowing users the advantage of unobtrusive corrosion protection during the transit, storage, or maintenance phase. Contact Cortec® today to learn more about using VpCI®-391:

Keywords: rust preventative coating, VCI packaging, corrosion prevention, metal shipping and storage needs, removable coating, keep weld surfaces corrosion free, preventative maintenance, Cortec, Cortec Coatings, transit coatings

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NEWS ALERT: Metal Cleaning and Flash Corrosion Protection Made Easy for Low Foam Applications

June 21, 2022

When cleaning or degreasing metals, it is important to choose a cleaning fluid that guards against flash rust. It is also important to consider the method of cleaning, since high pressure and high agitation can create a foaming mess. To address both concerns, Cortec® Corporation offers VpCI®-418 LM, a non-foaming alkaline cleaner with flash rust protection.

Preventing Flash Rust on Freshly Cleaned Metal

Metals are especially susceptible to flash corrosion after cleaning, which is why Cortec® has developed VpCI®-41x series cleaners/degreasers that contain flash rust inhibitors. These corrosion inhibitors are ideal for protecting metals that cannot be immediately coated. Other common uses include dual cleaning/corrosion protection of the following:

  • Machinery, engine blocks, or forgings coated with grease or oil deposits
  • Plate, sheet metal, and metal castings covered with oily films prior to painting or pickling
  • Metal parts contaminated with stamping, drawing, or buffing compounds
  • Metal structures

Overcoming Foam Problems in Parts Washers

When cleaning the items mentioned above, foam is usually associated with a better cleaning experience. That changes with parts washers, where high agitation creates excess foam that could overflow out of the machine and onto the floor. Pressure washing and power washing can have similar problems. VpCI®-418 LM is good for both applications because it is non-foaming and performs best with mechanical action. VpCI®-418 LM can be used on a variety of metals (carbon steel, stainless steel, cast iron, galvanized steel, brass [30% Zn], copper) and may be used at different dosages for light, medium, or heavy-duty cleaning.

Next time you need to clean metal parts or structures in a high agitation environment, remember to take advantage of the flash rust corrosion protection and non-foaming aspects of VpCI®-418 LM. Contact Cortec® to learn more about our portfolio of flash rust inhibiting cleaners/degreasers:

Keywords: metal cleaning, flash corrosion protection, corrosion protection, cleaning and degreasing metals, flash rust protection, rust inhibiting cleaners, foam problems in parts washers, preventing flash rust, Cortec, VpCI

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NEWS ALERT: Formulating with Cortec® Coating Additives? Keep Foam Out of the Equation!

Cortec® offers a variety of VpCI® additives that formulators can use to boost the corrosion protection and salt spray performance of their own coatings. These additives are typically used at a much lower dose than others and are clean and efficient to add. However, the entire benefit of using a VpCI® additive is undermined when too much foam causes defects like pinholes, craters, and curtains. It is therefore imperative to know when a defoamer is needed to avoid these problems.

What Kind of Coating Are You Formulating?

The first sign that you will probably need a defoamer is when you are formulating a water-based coating. While water-based coatings often have important environmental and worker advantages, such as low VOC and easy cleanup, they almost always need a defoamer. This is less common in solvent-based coatings.

What Is the Target Application Method?

Another factor to consider is the expected method of coating application. Spray application is less likely to cause foaming problems, while vacuum coaters are notorious for creating “milk shakes”—paint with more foam than you know what to do with. Flow coaters also have the tendency to create “curtains” where entire strips of metal remain uncoated because an air bubble blocked the paint from flowing underneath that spot.

What Else Will You Be Adding to the Coating?

Coatings can contain dozens of different ingredients—each with a specific purpose—and can vary significantly from one formula to another. This means the defoamer that works for one coating may not work for another. For example, sometimes silicone defoamers may actually cause pinholes or craters due to how they interact with the other ingredients.

How to Choose the Best Defoamer

The best way to avoid foam and ensure that your Cortec® enhanced coating is a success is to talk with your defoamer supplier. Discuss the characteristics and target application of your new VpCI®-powered formula. Then try the recommended defoamers by adding them to the coating and doing a shake test or running them through a blender to see which one is best at reducing foam. It is also a good idea to apply the coating to metal to see how the finish is.

Maximize the Success of Your New Anticorrosion Coating

When you choose a Cortec® additive, the purpose is to make your coating perform better. One of the last things you want to happen is to have the coating fail because of too much foam. Next time you add a Cortec® VpCI® additive to your formulation, be sure to include a defoamer in the discussion to maximize the success of your new anticorrosion coating. Contact Cortec® for more advice on formulating coatings with VpCI® additives here:

Keywords: Cortec Coatings, coating additives, corrosion protection, salt spray performance, low VOC, water-based coating defoamer, silicone defoamers, how to choose the best defoamer, make your coating perform better, anticorrosion coating

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PRESS RELEASE: VpCI®-373 Wash Primer: The Path to Good Coatings Adhesion on Galvanized Steel and Aluminum

Good adhesion is critical to the success of a coatings system, especially when painting metal to protect it from corrosion. Although many of Cortec’s Micro-Corrosion Inhibiting Coatings™ are designed to be applied direct to metal (DTM coatings), a primer is often recommended for improved adhesion. Extra care must be taken for galvanized steel, aluminum, and other metals where adhesion is more difficult. Cortec’s VpCI®-373 serves this purpose as an excellent wash primer for creating a strong bond between metal surfaces and the paint that protects them.

Common Methods for Improving Coating Adhesion
Common methods for improving adhesion on galvanized steel and aluminum include the following:

• Chromate pretreatment/conversion coatings for unpainted aluminum
• Lead and zinc chromate primers for galvanized steel
• Acid etching on galvanized steel
• Applying a wash primer

The first three options have obvious downfalls due to the use of heavy metals and harsh acids that could be harmful for workers. The fourth is an excellent way to keep paint application simple. Wash primers typically are very thin yet promote good adhesion between the metal surface and the chosen topcoat. This can help the protective coating last longer instead of failing prematurely. Without good adhesion, the coating is destined to peel or flake early, giving corrosives free access to the metal surfaces.

VpCI®-373 Wash Primer
VpCI®-373 is a water-based wash primer that creates a good bond on metal surfaces such as galvanized steel or aluminum where adhesion is difficult. VpCI®-373 can be applied at an extremely thin DFT (dry film thickness) of 0.5-1.0 mils (12.5-25 µm) and top-coated with a wide range of water-based or solvent-based Cortec® MicroCorrosion Inhibiting Coatings™ for corrosion protection. It creates a strong bond between the metal and its protective coating to enhance durability and longevity. It can replace chromate treatments and conversion coatings and is an excellent alternative to acid etching in terms of both safety and convenience.

Coating Galvanized Roofing Sheets
VpCI®-373 was used to answer the adhesion question when painting a galvanized roof over a liquid nitrogen loading dock at an industrial site in the Philippines. Lead and zinc chromate based primers had not been enough to avoid adhesion problems, and etching of the galvanized coating with phosphoric acid was expected to lead to coatings failure within a year. This time, the customer chose to clean the new roofing material and apply VpCI®– 373 as a primer, followed by a topcoat of VpCI®-386. VpCI®-373 worked better than standard red lead or zinc chromate primers and was found to fully adhere to galvanized iron roofing sheets.

Good Adhesion or Failed Protection
Corrosion inhibitor coatings lose their value as soon as they begin to peel off the metal they are designed to protect. When special alloys such as galvanized steel or aluminum make adhesion more difficult than normal, VpCI®-373 steps in to provide a proper bond between the metal and the chosen paint, uniting them in a powerful anticorrosion coatings system to make protection more effective. Contact Cortec® to learn more about VpCI®-373 and the means of achieving good coating adhesion:

Keywords: wash primer, good coatings adhesion, painting metal, corrosion, corrosion inhibiting coatings, Cortec, direct to metal coatings, corrosion protection, improving coating adhesion, coating galvanized roofing sheets

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CASE HISTORY SPOTLIGHT: Case History #336: Protective Coatings for European Extrusion Plant

The owner of a film extrusion plant in Croatia needed a full protective coatings system that was cost-effective, easy to apply, and took the environment into consideration. Cleaning, adhesion, and overall appearance were other important factors.

All silos, light poles, and the floor were first cleaned with VpCI®– 414 Cleaner/Degreaser (sometimes diluted 15% with water). One coat of VpCI®-386 Green was applied to the silos. VpCI®– 386 Green was also used as a topcoat on the light poles after priming them with VpCI®-373 to improve adhesion to the galvanized surface. MCI®-2026 Concrete Primer and MCI®-2026 Floor Coating were applied to the floor. A Cortec® water-based coating system was also applied to the extrusion line before the manufacturer shipped it from Italy to Croatia.

The Cortec® Coatings allowed the extrusion plant to easily apply a color-coded coatings system that promotes safety and corrosion protection while employing several water-based products.

Keywords: protective coatings, improve adhesion, priming galvanized surface, water-based coating system, Cortec Coatings, floor coating, MCI, priming light poles, corrosion protection

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