Auto Certification testing - American Chemical Society

The program assures that future model-year ... vices to control automotive emissions. .... course. This is the “durability data fleet” used to est...
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Auto certification testing The program assures that future model-year cars meet federally established exhaust emissions and fuel economy levels William A. McConnell Ford Motor Company Dearborn, Mich.481 21 Since the early fifties when the automobile was first identified as a major source of air pollution, the industry, prodded by federal ambient air standards, has been hard at work on devices to control automotive emissions. Much progress has been made. For the 1978-model year, cars sold anywhere in the U S . except California are meeting federal standards of 1.5 g/mi (gpm) for hydrocarbons (HC), 15 gpm for carbon monoxide (CO), and 2.0 gpm for oxides of nitrogen (NO,). Achieving these levels has reduced H C emissions by 90%, C O emissions by 83% and NO, emissions by 67% from emission levels of uncontrolled vehicles-an overall improvement of 80%. In California, the automotive industry is complying with even more stringent standards: 0.41 gpm for HC, 9.0 gpm for C O and 1.5 gpm for NO,. Added to these emission standards is the Corporate Average Fuel Economy (CAFE) standard, which calls for a fleet average of 18 mpg for all of the cars a company manufactures in the 1978-model year and an average of

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27.5 mpg for 1985. It is not simply an average based on the fuel economies of a given number of vehicles. It’s a production-weighted, fuel economy average that reflects the amount of gasoline used for an entire fleet to travel a given number of miles.

The impetus Car manufacturers must meet the emissions standards before they can ship their cars to dealers for sale, and the fuel-economy standard includes a stiff penalty of $5/vehicle for every one-tenth of a mile that a manufacturer exceeds the standard, multiplied by the total number of cars produced in any given model year. For a company like Ford Motor Company, which could sell as many as three million cars in the expanded markets projected for the 1980’s, the penalty for missing the standard by a full mile could add up to $150 million after taxes. Meeting the standards then is one of the most important aspects of building and selling cars today. The industry has responded to this challenge with the development of control hardware and systems ranging from the inexpensive Positive Crankshaft Ventilation (PCV) device installed on cars sold in California in 1961. to the so-

1978 American Chemical Society

phisticated Exhaust Gas Recirculation (EGR) and catalytic converter systems (ES&T, September 1975, p 820) on current automobiles. The technology will be even more sophisticated in the future.

Emissions testing In addition to the development of control technology, the identification of the automobile as a source of air pollution created another complex and costly activity in the automobile industry-emissions testing, which begins in research test cells and goes through the final assembly of production vehicles. The major activities are federal certification testing, where representative vehicles are tested for the forthcoming model year, and advance engines and emissions-control devices are tested to establish that they will meet applicable control standards and contribute to the company’s efforts to achieve CAFE before the vehicles are committed to production. At Ford, most of this testing is performed at laboratories in Allen Park and Dearborn, Mich., which combined, provide 111 000 ft2 of space and 43 dynamometer test cells. These facilities are busy around the clock (three shifts), six-to-seven days a week, with about 1000 employees. In addi-

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tion, the company has a high-altitude test laboratory in Denver, Cola., that has four chassis dynamometer cells and 40 soak spaces in 24 000 ft2 of space. The steps taken The actual emissions certification effort for the next model year starts a full year ahead of the model year for which the cars are being tested. In about July of each year, the company submits a Part I Application to the EPA. This application provides detailed descriptions of the complete product line the company intends to offer in the model year, including ve-

both test fleets is accumulated on Ford test tracks at Dearborn and Romeo, Mich., and on chassis dynamometers. The actual certification test is an eight-stage procedure on which the company spends roughly $40 million annually. Ford runs the vehicles some 6 million test miles through about 7500 tests on dynamometers and on the test track. The work amounts to some 250 man-years. Important in the certification process is what is called an “emissions deterioration factor” as the vehicle moves from low to high mileage. This is determined by taking a least-square

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hide bod! styles and sizes as well as the model mix 3nd ootions to be offered. Planned production volumes for each vehicle model, a detailed description of each engine the company plans to build, a detailed description of all of its emissions-control systems, and a detailed description of all company emissions test facilities also must be included. Test facilities have to be certified by the EPA. From this application, the EPA specifies two fleets of mandatory test vehicles. One fleet-of about 90 vehicles in Ford’s case-must he run for 50 000 mi (50K) over a prescribed test course. This is the “durability data fleet” used to establish the deterioration rate. Another fleet-of 100-120 vehicles for Ford-is made up of 4000-mi (4K) test vehicles in which virtually every vehicle-engine combination Ford plans to produce must be represented. These vehicles also must be run over the same prescribed course, and subsequently tested at the EPA laboratory. The required mileage for 394

Environmental Science 8. Technology

the 50 000-mi testing can usually he prepared from components used for current model-year vehicles. The 50K certification test The first step in the 50K test is to determine emissions levels at zero miles. These results are submitted to the EPA with descriptions of the certification vehicles. If all paperwork is in order, the EPA will authorize mileage accumulation. From there, 50K results are recorded at every 5000-mi increment, and before and after each major maintenance interval. And, although most of this is done

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