Trailer Makers Apply Treatments, Add Metals to Combat Corrosion

This story appears in the Dec. 8 print edition of Transport Topics.

Road treatment chemicals designed to remove snow and ice are wreaking havoc on trailer components, forcing manufacturers to add metals, apply special coatings and redesign parts to provide extra durability.

Some of the key culprits inflicting damage are liquid de-icers such as magnesium chloride, potassium chloride and calcium chloride, which states use to treat roads, shifting away from traditional sand and rock salt.

“The liquid chemical that they put down is a great idea for the road. The problem is that it works the same way under that trailer,” said Mike Dennis, group director of field maintenance at Miami-based Ryder System Inc., noting that properties that make the chemical stick to the road also make it stick to the trailer. And if not properly cleaned, those chemicals never get completely rinsed off.

Ryder Supply Chain Solutions ranks No. 11 on the Transport Topics Top 100 list of the largest for-hire carriers in the United States and Canada.

“The liquid de-icer is put on the road prior to a snow or ice event, and it sticks well,” said Keith Limback, general sales manager for Manac Trailer, based in Freeport, Pennsylvania. “As soon as it has contact with any kind of liquid, it

activates and gets thrown onto your vehicle. And as soon as you have a spring shower or summer shower, it is reactivated because it gets wet. Now you have potentially year-round corrosion.”

Even worse, different states use different chemicals, which build up on a trailer as drivers travel cross-country. “Not only is a trucker getting chemicals on his trailer, he is getting a chemical cocktail that may accelerate the corrosion process,” said Brett Olsen, marketing manager for Utility Trailer Manufacturing, in City of Industry, California.

Combating those cocktails starts with using the right combination of materials. Some metals have more natural resistance to rust than others, and manufacturers are using many metals in a single trailer, strategically placing the right material in the right place.

Stainless steel is one of the top corrosion-resistant metals. Utility uses it on the doorframe. “It is at the back of the trailer, where all of the junk from the road, the salt and the chloride, ends up,” Olsen said.

Carriers can spec stainless steel in other parts of the trailer, said Bob Douglas, vice president of field maintenance for Penske Truck Leasing’s Northeast Region. He said the company orders stainless steel for the front radius and rear headers on trucks that run in certain regions, an investment that pays off in more uptime and less maintenance, he said.

“We look at the number of shop visits,” Douglas said. “There is a [return on investment] in me being able to provide more uptime for my customer.”

Penske Logistics, based in Reading, Pennsylvania, ranks No. 32 on the TT for-hire list.

Greg Walsh, director of maintenance for New World Van Lines, based in Chicago, has switched to stainless steel on some components. “We’ve also had some different materials in different latches and some Mylar-type material between panels that has made a difference,” he said.

Mylar tape is used to prevent corrosion caused by matching two types of metal, said Steve Zaborowski, senior vice president at St. Louis-based Xtra Lease. As a basic rule of thumb, he said, steel and aluminum shouldn’t be touching.

“Between the bottom rail of a trailer and the cross members that are traditionally made of steel, there is Mylar tape that goes between those to prevent corrosion,” he said, adding that maintaining that film is important when making repairs or replacing components.

In addition to using a Mylar barrier between dissimilar metals, MAC Trailer Manufacturing, based in Alliance, Ohio, paints on a material called ECK. “Many manufacturers use only ECK or Mylar. Very few use both together,” said Lenny Miller, product manager for flatbeds at MAC Trailer Manufacturing.

Manufacturers are also working to get more longevity out of carbon steel parts, such as the rear bumper and cross members, by dipping the pieces in molten zinc, which adheres to the metal and enhances protection from the elements. Dennis said the zinc coating is one of the better corrosion fighters. “It stays longer and is harder to penetrate,” he said.

Not only does the process — called galvanization — add a layer of thickness, it has certain properties that can slow corrosion, said Mark Ehrlich, business development manager for Wabash National Corp., based in Lafayette, Indiana. If it is put in a salt bath, zinc becomes a sacrificial metal by fading away and preserving the base material, he said. Zinc is also mixed into paint and primers used by most manufacturers, Olsen said.

Ehrlich said that even if paint is scratched down to the bare metal, the zinc surrounding the scratch slows the surface corrosion with its presence. “It can be more forgiving as to the time it starts to rust,” he said.

Stoughton Trailers, based in Stoughton, Wisconsin, uses zinc in its primer, and Scott Nachreiner, a company spokesman, said its painting process protects against corrosion.

“We grit blast it first to get the impurities off. Then we put on the epoxy primer, and then we bake it. Then we paint it and bake it again,” Nachreiner said.

Customers can spec stainless or galvanized components in certain areas of Stoughton Trailers, such as the rear frame, coupler and landing gear. “Galvanized is becoming more popular, but there are some other issues that need to be addressed,” Nachreiner said, adding that it increases the cost and is more toxic during welding.

Xtra Lease said trailer manufacturers have found more efficient and effective ways to galvanize metals, which has accelerated the adoption rate. He added that it is hard to calculate a specific ROI on galvanization, but said the company is investing in it. In 2014, Xtra Lease ordered about 5,000 new trailers, most of which had galvanized rear doorframes, rear bumpers, and landing gear bracing and wing plates, Zaborowski said.

To get zinc into as many areas as possible, Manac changed the trailer design on its flatbeds, going to a modular design so individual pieces could be hot-dipped galvanized or painted before assembly.

“What is key about the modular design is it allows coverage in the nooks and crannies where you would not necessarily be able to get good coverage,” Limback said, adding that galvanization is standard on some parts and an option on others. “More and more people are taking advantage of the hot-dipped galvanized option,” he said.

All Erection and Crane Rental Corp., in Cleveland, ordered 104 Manac trailers with galvanized steel decks to reduce corrosion. The company estimates the trailers will last three times longer than regular painted trailers, said John Bacci, the company’s director of logistics. “That’s a significant life-cycle upgrade.”

Manac also offers flatbeds made of aluminum, a metal that Limback said fights off corrosion better than carbon steel. He noted that, though aluminum was chosen to cut weight and increase payload, “we’re seeing more buyers buy the aluminum to combat the corrosion.”

MAC Trailer Manufacturing has made changes to the landing gear on its flatbeds. The company’s Jost

AX-150 landing gear uses an outer aluminum leg instead of steel. Miller said the aluminum leg is of lighter weight and eliminates the corrosion between the dissimilar metals.

MAC Trailer also has gone to aluminum air tanks, which mount to aluminum brackets, eliminating the use of dissimilar metals. “Most air-tank failures are due to mount bracket connection issues and steel tank corrosion from the inside out due to condensation over a period of years,” Miller said.

The use of undercoatings can provide an additional line of defense, and manufacturers said they’re working to improve the formulas for the noncorrosive materials to serve as a barrier between the underside of the trailer and the road.

“The lower part of a trailer body and the underside of the trailer are most susceptible,” said Charlie Fetz, vice president of design and development in Great Dane’s engineering department. “Proper selection of materials, coatings and dielectric barriers are more critical in these areas.”

Fetz said Savannah, Georgia-based Great Dane frequently works with manufacturers of cleaners and corrosion inhibitors to help them improve their products, but he declined to specify the manufacturers with which Great Dane works.

Utility uses an automotive-grade coating on its undercarriages, Olsen said. “It is a self-repairing coating, so when a rock comes up and hits it, rather than chipping away and leaving a piece of exposed bare metal, it damages it but will eventually bring itself back together,” he said.

Vanguard National Trailer Corp. in Monon, Indiana, uses a water-based undercoating as a final step. “Once the trailer is finished, it is rolled over a pit and sprayed with it,” said Mark Roush, vice president of engineering for Vanguard.

To help inhibit rust, Krown, based in Ontario, Canada, makes a product that can be sprayed onto a trailer and leaves an oil film behind to disperse any water or chemicals that spray up.

“The solution is designed to creep and penetrate to get in where other products can’t. It protects against corrosion and helps protect wiring and electrical components,” said Jeremy Young, vice president of Krown Corporate.

Krown has been in business for 30 years but entered the U.S. market only three years ago.

Protection First Class, a lubricant and rust inhibitor manufactured by Berkebile Oil Co., of Somerset, Pennsylvania, is sprayed on and forms a protective, friction-reducing film that can reduce corrosion, the company said. It is made from wool-wax lanolin and creates a moisture- and dirt-resistant coating on painted surfaces.

And even with advanced coatings and more durable metals, preventing corrosion requires continual care and an active approach, manufacturers said. That includes regular trailer inspections for even minor indications of corrosion, because the damage can take years to appear.

For example, galvanized steel won’t rust on the surface, but if the metal’s coating is penetrated, the chemicals can get in and start the reaction.

“The coating on galvanized [steel] is so thick and strong in its nature that it won’t bubble, like paint will, to show you have a corrosion problem. That corrosion will stay beneath the coating for a long time,” Olsen said.

Hyundai Translead did not respond to requests for comment.