New tire

The basic principles and approaches to manufacturing pneumatic tires have been in place for many years, and because of the scale of modem tire production, radical change is slow. However, developments of new tire production processes continue (44,45) and as new methods take hold, it is likely that changes in tire cord handling and preparation will be required. 

While a new tire may have excellent resistance to crack initiation and propagation between the steel belts, an aged tire of the exact same construction can exhibit dramatically reduced crack growth resistance, which in some cases may contribute to tire failure. To further underscore the point, the United States National Highway Traffic Safety Administration (NHTSA) determined that tire aging was a main contributor to the Firestone Wilderness AT tire recall [1]. Figure 34.1 shows the failure rate of Wilderness AT tires as a function of tire age (determined from date of tire manufacture). 

This paper discusses these recent developments and outlines how tire machinery manufacturers have developed possible solutions to adequately meet the needs of the fast-paced new tire design evolutions. 

G. Bohm and H. Mouri, Emerging materials—technology for new tires and other mbber products. Tire Technology International Annual Issue, 10, 2006. 

Using the information in table 1.4, the used-car ad can be divided into five moves. In the first move (included in all six ads), the seller states the essential facts about the car (year, make, and model). In the second move (included in all but two ads), the seller highlights select features of the car (e.g., new tires, air bags, five speeds). In the third move (interchangeable with the second), the writer offers a subjective description of the car (e.g., good cond or fun ). In the fourth move, the writer states the price. Finally, in the fifth move, the seller provides contact information (1) a phone number, (2) a contact name (optional), and (3) when to call (optional). 

North Carolina 1% Mies tax on new tires X X X X lunds/collection... 

Frequently, when one or two tires of a set are worn, the entire set is replaced with new tires. Useful tread may remain on several of the remaining tires. These tires are often sold for second cars or farm equipment. About 10 million tires per year are currently being reused. Although the reuse of partially-worn tires cannot be expected to solve the tire problem, reuse could potentially double based on the number of good tires currently thrown away. 

Most of the technologies available for mitigating the nation s scrap tire problem are limited by both economic and noneconomic barriers, and it is often difficult to separate the two. For example, the use of retreaded or used automobile tires is limited by competitive new tire prices, an economic barrier, as well as consumer concerns about safety and reliability, a noneconomic barrier. Designing tires to last 100,000 miles or more would cost considerably more and also would likely result in rougher rides and more tire noise. 

It is commonly accepted in the tire industry that about one tire per person per year is discarded. Since there is no industry group or governmental agency that monitors tire disposal in the United States, the best estimates that can be made are based on tire production. The Rubber Manufacturers Association (RMA) records the number of original equipment, replacement, and export tires that are shipped each year in the United States. (See Table 3.) In 1990, a total of 264,262,000 tires were shipped. The RMA data include new tire imports, but not imported used tires. To estimate the number of tires that were discarded in the United States in 1990, the following assumptions were made ... 

Includes imported new tires) National Petroleum News, Fact Book, 1986-1988. Data from the Rubber Manufacturers Association. 1988 through 1990 data from RMA Industry Monthly Tire Report, December 1989 and December 1990. 2/ U.S. Department of Commerce. U.S. Imports for Consumption (FT246). 1984-1990. 

The National Tire Dealers and Retreaders Association claims that properly-inspected retreaded tires have lifetimes and failure rates comparable to new tires. Mileage guarantees and/or warranties for retreads are often similar to or identical to new tire warranties. 

Reclaim rubber tends to lose its elastic properties during processing and, therefore, is no longer extensively used in tires because of the flex needed. That is, it does not become like new rubber. Howeyer, some new tires routinely contain one to 2 percent crumb rubber (5). 

Because of the increased use of synthetic materials in making new tires after World War n, the reclaim industry has dramatically decreased in size. During World War n, about 60 percent of the rubber in tires was reclaimed rubber. Each of the major tire manufacturers has discontinued operating reclaim plants in the last 8 to 10 years, until now only about one to 2 percent of the raw material for tires is reclaim. There are currently only two companies that produce reclaim rubber, i.e., partially-devulcanized rubber, from whole tires for use in tires and other rubber products. These companies are Midwest Rubber Reclaiming Co. in East St. Louis, Illinois and Rouse Rubber, Inc., in Vicksburg, Mississippi (22). 

Congress has been considering numerous pieces of legislation that pertain to the management of municipal solid waste. Some of these focus particularly on scrap tires. One innovative approach under discussion is a credit system. Manufacturers would only be allowed to produce a new tire if a given number of tires were recycled, processed, and/or burned for energy recovery. 

HC S,P.H IX talea tax on new tire finds county tire collection tlree euet be cut... 

OK S,P Sl/tlre surcharge new tire aalea grants tires aust be cut... 

VA S.50/tlre dltpoael fee on new tire alee finds/testlng ... 

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