Source: http://www.law.cornell.edu/cfr/text/40/86/appendix-VIII
Timestamp: 2013-05-19 12:43:44
Document Index: 652554864

Matched Legal Cases: ['art 86', 'art 86', 'art 86', 'art 86', '§ 86', '§ 86', 'art 86', '§ 86', '§ 86']

40 CFR 86, Appendix VIII to Part 86 - Aging Bench Equipment and Procedures | Title 40 - Protection of Environment | Code of Federal Regulations | LII / Legal Information Institute
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40 CFR 86, Appendix VIII to Part 86 - Aging Bench Equipment and Procedures
Pt. 86, App. VIII
Appendix VIII to Part 86—Aging Bench Equipment and Procedures
This appendix provides specifications for standard aging bench equipment and aging procedures which may be used to conduct bench aging durability under the provisions of § 86.1823-08.
1. Aging Bench Configuration
The aging bench must provide the appropriate exhaust flow rate, temperature, air-fuel ratio, exhaust constituents and secondary air injection at the inlet face of the catalyst.
a. The EPA standard aging bench consists of an engine, engine controller, and engine dynamometer. Other configurations may be acceptable (e.g. whole vehicle on a dynamometer, or a burner that provides the correct exhaust conditions), as long as the catalyst inlet conditions and control features specified in this appendix are met.
b. A single aging bench may have the exhaust flow split into several streams providing that each exhaust stream meets the requirements of this appendix. If the bench has more than one exhaust stream, multiple catalyst systems may be aged simultaneously.
2. Fuel and Oil
The fuel used by the engine shall comply with the mileage accumulation fuel provisions of § 86.113 for the applicable fuel type (e.g., gasoline or diesel fuel). The oil used in the engine shall be representative of commercial oils and selected using good engineering judgement.
3. Exhaust System Installation
a. The entire catalyst(s)-plus-oxygen-sensor(s) system, together with all exhaust piping which connects these components, [the “catalyst system”] will be installed on the bench. For engines with multiple exhaust streams (such as some V6 and V8 engines), each bank of the exhaust system will be installed separately on the bench.
b. For exhaust systems that contain multiple in-line catalysts, the entire catalyst system including all catalysts, all oxygen sensors and the associated exhaust piping will be installed as a unit for aging. Alternatively, each individual catalyst may be separately aged for the appropriate period of time.
4. Temperature Measurement
Catalyst temperature shall be measured using a thermocouple placed in the catalyst bed at the location where the highest temperature occurs in the hottest catalyst (typically this occurs approximately one-inch behind the front face of the first catalyst at its longitudinal axis). Alternatively, the feed gas temperature just before the catalyst inlet face may be measured and converted to catalyst bed temperature using a linear transform calculated from correlation data collected on the catalyst design and aging bench to be used in the aging process. The catalyst temperature must be stored digitally at the speed of 1 hertz (one measurement per second).
5. Air/Fuel Measurement
Provisions must be made for the measurement of the air/fuel (A/F) ratio (such as a wide-range oxygen sensor) as close as possible to the catalyst inlet and outlet flanges. The information from these sensors must be stored digitally at the speed of 1 hertz (one measurement per second).
6. Exhaust Flow Balance
Provisions must be made to assure that the proper amount of exhaust (measured in grams/second at stoichiometry, with a tolerance of ±5 grams/second) flows through each catalyst system that is being aged on the bench. The proper flow rate is determined based upon the exhaust flow that would occur in the original vehicle's engine at the steady state engine speed and load selected for the bench aging in paragraph (7).
a. The engine speed, load, and spark timing are selected to achieve a catalyst bed temperature of 800 °C (±10 °C) at steady-state stoichiometric operation.
b. The air injection system is set to provide the necessary air flow to produce 3.0% oxygen (± 0.1%) in the steady-state stoichiometric exhaust stream just in front of the first catalyst. A typical reading at the upstream A/F measurement point (required in paragraph 5) is lambda 1.16 (which is approximately 3% oxygen).
c. With the air injection on, set the “Rich” A/F ratio to produce a catalyst bed temperature of 890 °C (± 10 °C). A typical A/F value for this step is lambda 0.94 (approximately 2% CO).
8. Aging Cycle
The standard bench aging procedures use the standard bench cycle (SBC) which is described in appendix VII to part 86. The SBC is repeated until the amount of aging calculated from the bench aging time (BAT) equation [ref. § 86.1823-08 (d)(3)] is achieved.
a. The temperatures and A/F ratio information that is required to be measured in paragraphs (4) and (5) shall be reviewed periodically (at least every 50 hours) during aging. Necessary adjustments shall be made to assure that the SBC is being appropriately followed throughout the aging process.
b. After the aging has been completed, the catalyst time-at-temperature collected during the aging process shall be tabulated into a histogram with temperature bins of no larger than 10 °C. The BAT equation and the calculated effective reference temperature for the aging cycle [ref. § 86.1823-08(d)] will be used to determine if the appropriate amount of thermal aging of the catalyst has in fact occurred. Bench aging will be extended if the thermal effect of the calculated aging time is not at least 95% of the target thermal aging.
10. Startup and Shutdown
Care should be taken to assure that the maximum catalyst temperature for rapid deterioration (e.g., 1050 °C) does not occur during startup or shutdown. Special low temperature startup and shutdown procedures may be used to alleviate this concern.
This is a list of United States Code sections, Statutes at Large, Public Laws, and Presidential Documents, which provide rulemaking authority for this CFR Part.This list is taken from the Parallel Table of Authorities and Rules provided by GPO [Government Printing Office].It is not guaranteed to be accurate or up-to-date, though we do refresh the database weekly. More limitations on accuracy are described at the GPO site. Title 40 published on 2012-07-01The following are ALL rules, proposed rules, and notices (chronologically) published in the Federal Register relating to 40 CFR 86 after this date.2013-01-25; vol. 78 # 17 - Friday, January 25, 201378 FR 5347 - Denial of Reconsideration Petition on Model Year 2012-2016 Light Duty Vehicle Greenhouse Gas Emissions Standards