New Materials and Technology For Repairs on Truck Tires
Twenty years ago a new 1000 x 20 or 11 x 22.5 bias truck tire cost from $110 to $150 and many truckers did not bother having them repaired when they were cut or punctured. Part of the reason was the lack of knowledge by fleet owners and truckers that effective repair techniques were even available.
Today, things are different. Although a few bias tires are still retreaded and repaired very successfully, the predominant tire now in use is the radial tire, and a top of the line radial truck tire can cost up to $400. That's a lot of money to lose when the tire rolls over a spike.
GREATER REPAIRABILITY OR RADIAL TIRES VS. BIAS TIRES
Due to the unique construction and quality of today's tires, plus advances in state-of-the-art repair materials and repair methods, many of these tires can be routinely repaired and returned to full over-the-road service and in most cases can be retreaded when the original tread is worn off.
WHAT CAN BE REPAIRED?
Radial truck tire injuries up to 5-1/8" radially (length) x 3/4" (width) or 3-1/8" radially (length) x 1-1/2" axially (width) (wider repairs must be shorter in length) on the sidewall and 1-1/2" diameter in the crown area can now routinely be repaired, according to some tire repair material manufacturers. Punctures up to 3/8" can also be repaired. "Outside-in" or "on-the-wheel" type repairs should not be used.
TIRE SHOULD ALWAYS BE REMOVED FROM THE RIM AND THOROUGHLY INSPECTED FOR DEFECTS AND EXTENT OF DAMAGE BEFORE REPAIRING
PROPER REPAIR MATERIALS
The use of the proper repair materials is essential. For injuries exceeding 3/8" radial section units should be used for radial tires; bias section repair units should be used for bias tires. No exceptions. In the case of punctures (maximum of 1/4" for passenger ties; 3/8" for truck tires), the injury must be filled with a vulcanizing material to prevent injury growth of belt package separation and to protect against contaminations and moisture from entering the casing. The proper repair unit should then be applied to seal the innerliner.
If the injury is only repaired by applying a repair unit to the inside, future problems will occur. Even in small injuries it is critical that the injury is cleaned and filled. If this is not done, severe rust, separation and steel cable looseness could take a tire out of service and cause it to be scrapped. A tire taken from service early increases the operating costs of the fleet.
The injury should be inspected, and then cleaned out with a carbide cutter. After cementing the injury, a vulcanizing rubber stem should be applied into the injury. The innerliner is buffed, cleaned, cemented and then the proper repair is applied inside the tire. This would create a permanent repair that maximizes tire life. This offers the fleet or owner/operator extended radial tire life that provides the lowest operating cost per mile.
Today, even some types of bead area damages are repairable. Only properly trained repair technicians should perform these repairs. Tires with damaged bead areas should NOT be placed back into service until inspected and repaired by a qualified repair technician.
A few years ago the International Tire and Rubber Association conducted a research study on the strength of sidewall repairs in radial truck tires. Radial truck tires with injuries 4" long and 3/4" wide were repaired, x-rayed, and subjected to increased pressure until they burst.
From the results the International Tire and Rubber Association (now known as TIA) concluded that properly repaired sidewall injuries have a strength equal to that of the surrounding tire body and provide a safe performing product for the transportation industry.
WHAT ABOUT THE BULGE?
Repaired sections in radial tires may sometimes exhibit a slight bulge. New blue triangle identification logos are now being used by some tire repairers. the Commercial Vehicle Safety Alliance (CVSA) which inspects trucks for safety defects has adopted the blue triangular logo to help identify bulges caused by sidewall/shoulder area repairs. Those bulges due to section repairs are acceptable if they do not exceed 3/8" (1cm) in height. Tire Industry Association/TIA has a plastic TIRE FACTS card available with a 3/8" cut out which allows for easy measuring of a bulge.
For information on how to obtain a card, contact Tire Industry Association/TIA at 800-426-8835 or E-mail:firstname.lastname@example.org
TIRE REPAIRING IS RECYCLING
Tire repairs convert damaged tires into safe and usable products. Unfortunately, not all repairable tires are repaired. Recent scrap tire surveys have shown that up to 30% of alleged scrap truck tires were indeed repairable.
It's a sad fact that a lack of knowledge about tire repairs causes many trucking fleets to discard tires that could easily be repaired and placed back in service. Millions of dollars are being wasted every year when repairable tires are scrapped. And the expense is compounded when the cost of getting rid of the scrapped tire is taken into account.
The average cost of radial truck section repair is approximately $45.00, a fabulous bargain in extending the life of your up-to $400.00 investment, while lowering your tire cost per mile.
Today, the large majority of trucks are being fitted with radial tires. the radial tire must be repaired and serviced as an economic investment. The benefits of using radial tires will then be realized to a greater extent.
KNOW YOUR TIRE REPAIRER!
Always deal with a reputable dealer who understands how and what tires are repairable. Reputable dealers will warrant their product and service. Perhaps the single most important thing you can do is to visit the tire repairer's facility and inspect his operation in person, Any reputable tire dealer will welcome your visit.
For more assurance, look for a tire repairer who is a member in good standing of one or more of the following organizations: TRIB (Tire Retread Information Bureau) or TIA (Tire Industry Association).
Quality tire repair material manufacturers and some associations offer training seminars on the use of their materials to produce a professional, permanent and safe tire repair. Certificates for successfully completing these instructional courses are issued, and should be prominently displayed at the tire repair facility. The repair material manufacturers welcome members of the trucking industry to attend these seminars.
The Tire Retread & Repair Information Bureau extends thanks to ITRA, TANA, Rema Tip Top, Roadway Tire Company, Tech International and Truflex/Pang for contributing to this article.