Technology challenge: Cleaner IC engines.
The purpose: smog control. And the federal Environmental Protection Agency (EPA) appears ready, willing, and certainly able to follow California's lead for the other 49 states, a recent EPA staff memo indicates.
Late last year, the California Air Resources Board (CARB) set new standards directed mainly at forklifts with spark-ignited IC engines. CARB will limit emissions of volatile organic compounds (VOCs) and nitrogen oxides (NOx), seeking roughly a 75% cut in combined emissions of VOCs and NOx (see chart). VOCs and NOx are smog formers. Control technology to do so also would cut carbon monoxide (CO) emissions.
Designs for many new engines for lift trucks will be impacted as CARB phases in controls. Engines sold in California as early as model year 2001 will need to comply. EPA rules are due by 2004.
Existing forklifts are unaffected by the CARB or EPA plans. So there's no need to retrofit these vehicles with new engines or emission controls.
Air quality rule backed
Manufacturers of lift trucks, through the Industrial Truck Association (ITA), support the thrust of California's standard-improved air quality. But ITA questions how to meet the new limits under the tight timetable.
Speaking for ITA, Dunaway & Cross attorney Gary Cross told CARB last fall its rules are "technology-forcing." They pose a significant engineering challenge despite what's known and in use to control emissions from gasoline-powered vehicles on U.S. highways, he says.
Autos running on gasoline typically have a closed-loop fuel system with three-way catalytic control for VOCs, NOx, and CO. Electronic fuel injection hikes control efficiency. In contrast, many forklifts rely on carburetors and open-loop fuel systems.
ITA's Cross told CARB that "a few (emission) systems with closed-loop, three-way catalyst technology have been designed for forklift trucks." But he cautions that there are "serious questions" about emissions performance. Furthermore, operating and environmental conditions for IC forklifts vary greatly from auto usage on highways.
"The questions are perhaps most acute for our LPG (propane) systems, which are 70-80% of our spark-ignited products," Cross adds, "because there is no highway counterpart" to forklifts so powered. And "there are ample challenges on the gasoline side as well." In his view, the industry "will be stretched to the limits of technical feasibility" to meet the CARB timetable.
Follow Detroit's lead
EPA staff engineers say that forklift engine technology and emissions control have not kept pace with Detroit's auto engine advances. Agency staffers argue that lift truck makers "can cost-effectively adapt at least the basic elements" of auto technology.
"Gasoline-fueled engines can utilize established fuel injection technology, while LPG- and natural-gas-fueled engines can likely achieve a comparable level of emission control with closed-loop carburetor-type fuel systems or new gaseous fuel injection systems," EPA says. Agency staffers concede, however, that the latter "have not proven themselves to the same degree" as gasoline-fueled injection technology.
Who will develop and certify engines to a CARB or an EPA standard also is an undetermined issue right now. Only one firm, as of press time, appears ready to fill this role.
"We do not expect to be able to purchase certified engines from our traditional engine suppliers," says Cross. These suppliers have "overwhelming business interests in designing and manufacturing highway engines. They already limit production for the non-road sector to partial engine assemblies, not complete engines."
Lift truck makers now buy engine blocks. Then they complete engine assembly by "dressing out" blocks with fuel-system and exhaust-system components from third-party vendors. Included among the vendors are some ITA members.
Forklift suppliers with both an auto side to manufacturing and a forklift side will already have the fundamental gasoline-fueled forklift control technology. Such firms may opt to provide certified engines.
"Some forklift manufacturers," says ITA's Cross, "at least in the beginning, will contract with a third party to be the engine manufacturer."
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|Title Annotation:||internal combustion|
|Publication:||Modern Materials Handling|
|Date:||Apr 30, 1999|
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