Savings in the Casings

If the tread is the face of the tire, then the casing is the heart that makes the tire live. That’s how Phil Mosier, Cooper Tire manager of commercial tire development, describes the importance of the casing.

“Tread pattern and the cost of the tire get a lot of attention from fleet managers running logging trucks,” says Mosier. “But it’s the casing that is often the unsung hero in a commercial tire. It’s the foundation of the tire and what allows you to receive multiple retreads. It’s the true driver in lowering your overall cost of ownership. I always advise fleets to look at the tire, then look even closer at the foundation of the tire. The casing.”

With advancements in technology, casing designs, and compounding formulas over the years, tires have never been more “retreadable” than they are today. Roughly half the commercial tires on the road are retreads, according to the United States International Trade Commission.

According to Mosier, one of the best gauges for determining casing quality is the warranty attached to the tire. “Twenty years ago, the typical warranty for a commercial tire was about four years, with one retread,” he says. “Now it’s up to seven years and multiple retreads. The warranty is really based on data analysis and the confidence the tire manufacturer has in the casing and the retreadability of the tire.”

Structural Integrity

Mosier emphasizes that structural integrity of the tire casing is vital. “Roughly 75 percent of what you pay for in a tire is in the casing,” he says. “We’ve gone with a little wider tire, and thus casing, in our drive and steer positions — that does a couple things. It gives better traction and more miles to removal since there is a bigger footprint, and it gives a wider width in the casing after it’s buffed for retreading. This allows our casing to hold up better for multiple retreads while supporting premium retread widths that deliver enhanced on-road performance.”

For enhanced strength, integrity, and fuel efficiency of casings, Mosier says the core areas are the innerliner, sidewall, bead area, and belt package. In Cooper’s case, their team is constantly tinkering with the compounds and materials used in the casing — little things make a big difference.

Mosier says, “The quality of the innerliner, for example, can vary across the board. The best innerliners help lower permeability — or the slow diffusion of air out of the tire. And we’re seeing the use of lightweight steel now in the belt package, which provides further protection to the casing from punctures.”

Most of the top tier tires feature three or four-steel belt designs. “We go with four belts, which we feel helps the integrity of the tires’ casing,” says Mosier. “That fourth belt gives an added layer of confidence and protection — especially against stone drilling and punctures. Rust is a tire’s enemy, and the extra steel belt helps protect the belts below.”

While most fleets retread, others sell their casings. “The beauty of having tires with quality casings is that even if you decide not to retread a tire, there is a market for your casing,” says Mosier. “Retreaders will pay you a pretty penny for your casing as long as it is in good condition. Even if you don’t plan on selling your casings, it’s a good idea to see what a retreader is willing to pay for it. That, right there, will tell you the quality of the casing you have.”

According to Mosier, retreaders won’t accept tires that can’t be safely retreaded. They thoroughly inspect tires before they are retreaded to make sure the casing is in good condition. Oftentimes, retreaders will think twice about accepting specific tire brands based on the reputation of their casings. “At the end of the day, a retreader is accountable for the tire that they retread, so they aren’t going to retread a tire if they don’t trust the casing,” says Mosier.

Give Your Casing the Longest Life Possible

In order to reap the cost-saving benefits provided by running retreaded tires or selling the casing, managing a proper tire maintenance program is just as important.

“If your drivers aren’t going through their pre-trip inspections, evaluating the conditions of their tires and consistently checking tire pressure, or the maintenance shop isn’t up to par with rotations and alignments, then the tire’s casing will be more prone to damage,” says Mosier. “Additionally, if your drivers are especially tough on tires, and you pull tires at the latest 32nds possible, then early failure may occur. If a retreader sees damage to the casing, they’ll declare the tire ‘unretreadable’ and now you no longer hold value in that tire. Common reasons tires are rejected are due to damage caused by running underinflated tires or by overloading them. Or by damage caused by running over sharp timber debris or sharp rocks.

The No. 1 thing you can do to ensure your tires are in good retread condition is to make sure you maintain proper tire inflation levels. “It’s by far the most important thing you can do,” says Mosier. “Under-inflation builds heat in the tire and can cause rubber to fatigue and stress quickly.”

Remember, not only can the tread and belts be negatively impacted by underinflation, but the rest of the casing can show signs of stress when not properly inflated.

Which Casings Are Best? Ask a Retreader

According to Mosier, the best way to identify the tires with the best casings is by simply asking your local retread shop. Retreaders are at ground zero. They know casing quality, and they see firsthand which tires are often rejected for retreading and which boast a high-retread rate.

“Getting an unbiased industry expert’s opinion on which tires have the best success retreading is invaluable,” says Mosier. “They’ll know if the tires you’re currently running have good casings or if there are better options out there.”

After checking in with the retreader, Mosier suggests checking the length of warranty of the tires you’re interested in and how many retreads the tire manufacturer will cover. It will give you additional perspective on how many retreads you can expect to receive from a tire.

For Cooper Tire, Mosier says the company is always comparing and benchmarking the quality of its casings against its competitors to see where they rank. “It’s our own litmus test,” he says. “We recently analyzed stats at two large retread shops — with data on close to 100,000 tires. Retreadability rates for specific brands ranked from 89 percent to 75 percent. So it goes to show there is a significant range and difference in quality. Overall, we came in at the top three in retreadability, which reaffirmed where we like to be. For us, it’s a stamp of approval that our casings are living up to expectation.”

Casings of the Future

As development for the next generation of tires begins, Mosier can only speak for Cooper, but the company is going to place particular emphasis on developing casings that further assist the ability to reduce rolling resistance and improve fuel economy. “For our logging tires, we’re looking at next-generation sidewall compounds which can hold up to the most aggressive use and a robust bead area construction that can handle loggers’ increasing loads.”