Inspection System Detects Damaged Tires And Promotes Safety

October 03, 1997

CHAMPAIGN, Ill. -- Researchers at the University of Illinois have developed a fast, low-cost inspection system for evaluating the structural integrity of new and used steel-belted-radial truck tires. The instrument uses ultrasonic sound waves to detect ply delaminations, weakened, damaged or broken cords and other, potentially dangerous, hidden defects.

"Driving on underinflated radial truck tires can damage the steel cords in the sidewalls," said Henrique Reis, a professor of general engineering. "Overflexing of the tire may cause the steel cords to break, fray or delaminate, weakening the sidewall. When the tire is serviced, these weakened areas can rupture, releasing a high-pressure blast of air that can cause serious injury or death."

To inspect for hidden damage, Reis and graduate student Paul Golko use an analytical, nondestructive evaluation technique called acousto-ultrasonics. First, the researchers use an ultrasonic transducer to inject a sound wave into the side of the tire. The ultrasonic pulse then propagates along the sidewall, where it is picked up by another transducer and analyzed by a computer.

"Tires are scanned with measurements recorded every 0.3 degree of tire rotation, for a total of 1,200 samples," Reis said. "This angular sampling interval was chosen because it is smaller than the spacing between radial cords on the tire at the transducer locations. Therefore, we can test for damage in each individual cord. The entire measurement process takes less than a minute per tire."

By analyzing the attenuation characteristics of the transmitted signals, the researchers can evaluate and characterize damage within the tire.

"We can detect strained or damaged cords because the sound wave is not transmitted as efficiently as in a normal steel cord," Reis said. "The greater the damage, the higher the signal attenuation. If the signal disappears, the cord is broken. By studying the signals, we also can detect areas where the steel cords and rubber have separated."

A color-coded display shows not only regions of broken or damaged cords, but also areas where the steel cords are weakened to the point where the tire should be removed from service. By evaluating the residual strength in the sidewalls, the instrument can determine both a tire's remaining useful life and whether it is worth retreading.

"A typical used-tire casing may contain numerous defects by the time it is retreaded," Reis said. "To reduce the number of retreads that fail prematurely, all tire casings should be inspected for damage prior to retreading. For safety reasons, we don't want to use bad tires; but, for economic and ecological reasons, we don't want to throw away good tires that can be retreaded. This instrument enables us to easily distinguish between the two."

Reis and Golko will describe the new inspection system in a future issue of Tire Science and Technology.

University of Illinois at Urbana-Champaign

Related Steel Articles from Brightsurf:

How soft hair deforms the sharpest steel blades
Why do the edges of a steel razor dull from cutting far softer materials?

HKU super steel project attains major breakthrough
The Super Steel project led by Professor Huang Mingxin at the Department of Mechanical Engineering of the University of Hong Kong (HKU), with collaborators at the Lawrence Berkeley National Lab (LBNL), has made important breakthrough in its new super D&P steel (produced using a new deformed and partitioned method) to greatly enhance its fracture resistance while maintaining super strong in strength for advanced industrial applications.

Making stronger concrete with 'sewage-enhanced' steel slag
Researchers examined whether steel slag that had been used to treat wastewater could then be recycled as an aggregate material for concrete.

Buildings can become a global CO2 sink if made out of wood instead of cement and steel
A material revolution replacing cement and steel in urban construction by wood can have double benefits for climate stabilization.

Finding out the factors that most influence the steel corrosion in reinforced concrete
This process causes structures to deteriorate internally and can even cause buildings to collapse.

Corrosion resistance of steel bars in concrete when mixed with aerobic microorganisms
Dissolved oxygen in pore solution is often a controlling factor determining the rate of the corrosion process of steel bars in concrete.

Scientists invented how to improve steel properties by 100 times
Scientists from Tomsk Polytechnic University developed a new method of ion implantation that dramatically expands the application of the alloying process in the industry.

C. difficile resists hospital disinfectant, persists on hospital gowns, stainless steel
Surgical gowns and stainless steel remained contaminated with the pathogen Clostridium difficile even after being treated with the recommended disinfectant.

30 shades of steel: Scientists develop 'cheat sheet' for the creation of new steels
Researchers from the National University of Science and Technology 'MISIS' developed a database that will help create new grades of steels.

Metal foam stops .50 caliber rounds as well as steel -- at less than half the weight
Researchers have demonstrated that vehicle armor using composite metal foam (CMF) can stop ball and armor-piercing .50 caliber rounds as well as conventional steel armor, even though it weighs less than half as much.

Read More: Steel News and Steel Current Events is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to