Desired Attributes in Tire Construction
- Long-wearing tread
- Superior retreadability
- Excellent, even treadwear
- Resistance to stone retention
- Superior fuel efficiency
- Cut and chip resistance
- Low cost-per-mile
Advanced design technology and superior engineering are the reasons why Yokohama steel-belted radials are so frequently chosen for tough situations. Yokohama's goal is to produce radial truck tires that are the most trouble-free with the lowest cost-per-mile when compared with any other tire in the industry.
Finite Element Method (FEM) Design and Testing
The developmenta/design phase of each Yokohama radial truck tire incorporates state-of-the-art computer modules to examine individual tire elements. To ensure proper designs and maximum performance, this FEM evaluates stress and strain in each part of the tire by simulating operation under load. Shear, plunger and durability tests are performed on the tire components, resulting in tires that are stringently designed to perform at the highest levels for their intended use.
Yokohama, however, does not stop here. The tire undergoes a rigid series of on-vehicle tests under real-world conditions. Traction, rolling resistance and fuel economy are measured through every stage of tread life.
Whether on-road, off-road or pick-up and delivery, you can be assured that Yokohama produced the best possible tire for your application.
Strain Energy Design and Testing
Casing fatigue is also addressed by Yokohama. It occurs when strain and stress result in the failure of one or more of the casing's many elements. (Like a chain, a tire is only as strong as its weakest point.) The resulting force of these strains and stresses is called "strain energy" (strain x stress = strain energy). Yokohama uses this method to uniquely test radial truck tires and return results for design refinements.
In operation, truck tires are subjected to many more stress variables than passenger tires (e.g., higher inflation pressures, frequent load changes and multiple retreading). Therefore, the effect of strain energy on tire durability is particularly important.
Critical strain-energy points of a truck and bus radial
The graphic above shows the strain energy of a typical truck and bus tire. The highest level of strain energy occurs around the bead assembly and in the upper shoulder area of the belt edges.
Cross-section of a Yokohama truck and bus radial
The FEM allows Yokohama to design and reduce the tremendous strain levels in these two critical areas by optimizing the casing shape. Strain energy is decreased on the specific areas of the tire and distributed along the entire casing sidewall. This reduction in strain results in outstanding durability and superior retread characteristics.
The knowledge gained from this analysis is incorporated into Yokohama's newest generation of radial truck tires:
- New casing shapes optimized for durability have a 6 percent to 21 percent strain energy reduction at the belt-edge and bead turn-up areas over conventional designs.
- New compounds for cap treads, undertreads and sidewalls reduce the effects of fatigue on the tire and provide resistance to environmental pollutants.
- Post-production verification combined with computer-aided design, extensive off-vehicle testing and stringent on-vehicle monitoring ensures products that are proven to meet Yokohama's high standards.
Only after passing all these tests will Yokohama allow a product to be sold. It is for that reason that Yokohama tires are so often chosen for tough-usage situations such as waste hauling and material handling.
Subjecting our tires to rigorous pre-release checks ensures Yokohama's superior standards of consistency, reliability and durability. Customers and dealers can depend on trouble-free performance, as well as some of the lowest possible cost-per-mile efficiencies of any product in the industry.
This philosophy extends well beyond the original treadwear cycle, and into the retreading stages. Retreaders have consistently rated Yokohama casings among the most retreadable in the business. They have become synonymous with consistency and reliability.
Yokohama institutes critical measures to protect against undesirable occurrences with its radial truck tires. It creates a solid bond of trust and confidence between manufacturer and user.
Yokohama offers a wide spectrum of truck radials designed to meet any challenges, regardless of the duty they must face.