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If you're considering
the purchase of a new excavator, grader, or loader in the next year,
there's a good chance that the engine under the hood will be different
from what you're used to.
By Lynn Merrill
Since the early 1990s,
engine technology has been under a great deal of external pressure
from the Environmental Protection Agency (EPA) in relation to air-quality
emissions standards. In order to implement the mandated improvements
to diesel engine emissions, EPA adopted a tiered approach based
on engine horsepower. Tier 1 regulations went into effect in 1996,
and Tier 2 became effective January 1, 2001, for engines with more
than 302 hp, with additional regulations for lower-horsepower engines
going into effect over the next two years. Tier 3 regulations are
slated to go into effect in 2006, with a particular emphasis on
nitrous-oxide controls.
"Federal air-quality
standards will continue to get more stringent as we go forward,"
states Roe East, director of market strategy and product management
for Cummins Inc. in Columbus, IN. "EPA stair-steps us into
those regulations, depending upon the horsepower of the engine."
For engine manufacturers,
electronic controls will play a large role in helping to meet these
requirements and in providing greater interface between machine,
engine, and operator–especially in midrange and higher-production
machines. "As you move up the scale in complexity, you are
probably more interested in getting really good productivity out
of the machine since you've invested a lot of money, so your
equipment starts having a lot of electronic controls," notes
East. "The engine needs electronic controls to interface with
the equipment so they can talk to each other. [The controls] allow
us to optimize the engine to work best in that piece of equipment,
they allow us to maximize the efficiency of the engine for given
horsepower and emission levels, [and they] allow us to provide things
that are of interest to the business owner. Engine protection systems
monitor the health of the engine and prevent damage from occurring
to the engine by allowing the owner to extract business information
out of the engine, like the amount of fuel consumed during the amount
of hours in use."
Implementing the Guidelines
The challenge to manufacturers
is how to implement the regulations into engine design. "We
are continuously working on technology," maintains Tom Withers,
manager of sales promotion for John Deere Power Systems in Waterloo,
IA. "We work very closely with the government agencies in Europe,
the US, Japan, and other places that we do have to comply with.
When these regulations are released, they are not total surprises
because we have worked with them and understand what is implied.
Then we bring our technology along in line with those assumptions.
Once we get the regulations understood, we focus in the appropriate
directions, which may require some different technologies for different
engine models."
Engineers face a juggling
act when it comes to striking a balance between meeting emission
regulations and meeting customer expectations for performance. "The
off-road markets are very demanding," observes Scott Crowley,
application delivery engineer for John Deere. "Our customers
expect to have the torque response to meet their needs when performing
multiple tasks, so from an engine standpoint they expect to have
this performance in lieu of the emission standards. As we look to
the different emission standards becoming more stringent, from an
engine manufacture standpoint, we cannot afford to have degradation
of performance for our customers. And we receive a lot of pressure–both
from our customers and the engineering communities–to be aware
of the cost when implementing the new technologies to meet the regulations."
Making the impact of
the regulations clear to the customer is critical, says Gary Stanek,
director of engine and engine systems engineering for Case Corporation
in Burridge, IL. "Our goal is to preserve and improve overall
engine and machine performance in the areas of power, power rise,
torque, torque rise, and low-speed torque response. We are working
hard to minimize fuel consumption as part of this process. From
a life cycle cost perspective, we've taken steps to reduce
some of the maintenance items, such as the frequency of oil and
filter changes on the engines, where possible."
Watch Those Maintenance
Intervals
One of the side effects
of the tighter air regulations is the tendency to reduce engine
maintenance intervals. "If we do nothing to the engine as we
try to meet the emission requirements, you would tend to see maintenance
intervals shortened, which isn't good for the contractor,"
points out East. "We've designed our Tier 2 engines to
mitigate this impact. You'll see that most of our engines have
maintenance schedules identical to today's engines. What you
will see is they need to use high-quality lubricants and fuels for
our engines to maintain those sorts of maintenance intervals. It's
always better, with more sophisticated fuel systems, to make sure
you're using good-quality fuels."
As these new engines
enter the marketplace, a contractor's ability to fix problems
with duct tape and coat hangers will be lost to onboard diagnostic
systems that can help keep a small problem from becoming a large
one. "We strive very hard to ensure that we have durability
in all these areas: components, features, and so forth," states
Dick Norton, project manager/advanced emissions control technology
with John Deere. "Electronics brings diagnostic tools that
can be used by the service people to very quickly tell if there
is something not quite right, what it is, and what to do to take
care of it."
Adds Crowley, "Now
we have the capability to display diagnostic codes on the monitor
so it's highly visible to the customer at that point in time
if there is a problem. It eliminates some of the confusion or guesswork
that the customer may have."
The Quest for Alternative
Fuels
Although EPA's requirements
for tighter air-emissions standards form the basis for much of the
current work in engine technology, the push for alternatives to
diesel fuel is being considered, especially in nonattainment areas
such as southern California. Recent rule promulgation by the South
Coast Air Quality Management District has placed a greater emphasis
on the use of fuels, such as compressed natural gas (CNG), liquefied
natural gas (LNG), and propane. For some engine manufacturers, this
represents a new market potential, while for others, the technological
and logistical issues remain to be worked out.
Recently, Cummins formed
a joint venture with Vancouver, BC—based Westport Innovations
to develop and market a series of high-pressure, direct-injection,
natural-gas engines. "These engines eliminate the need for
spark plugs in the emission systems and provide fuel economy on
natural-gas fuel comparable to diesel engines," reports East.
Thus, the engines operate with the torqued power and fuel efficiency
of a diesel, but with natural gas as the primary fuel.
"The way that a
diesel engine ignites fuel is that air goes into the engine cylinder
and is compressed–the compression creates heat," explains
Alan Bayless, manager of media and industrial relations with Westport.
"When you add diesel fuel to the hot air, the diesel fuel ignites
just from the heat of the hot air, without a spark plug. Natural
gas is harder to ignite, and it won't ignite consistently just
from the hot compressed air. Our technology is designed to use a
single fuel injector that has a capacity to inject two fuels into
the engine. The injector has the same shape and form as the diesel
fuel injector, so it can sit where the diesel injector would fit.
It delivers a very small amount of diesel at the point of maximum
air compression, and the diesel ignites as soon as it hits the hot
air. Then there is a larger amount of natural gas injected, and
the natural gas ignites from the combusted diesel fuel."
The Market's
Potential
Although this technology
is not yet available in off-road equipment, the potential for its
use is currently being explored. One of the largest barriers to
successful implementation of alternative fuels in grading and excavation
equipment lies in the logistics of fueling the equipment. "We
think we've got the engine and technology to meet that need
when the market comes to that technology," states East. "Natural
gas poses a packaging issue for off-highway equipment, since the
logistics of fueling it poses an issue for the industry." Although
mobile fueling rigs that provide diesel delivery to the job site
are common, the transportation issues relating to onsite fueling
of LNG or CNG equipment are in the embryonic stage.
This challenge is being
investigated by other manufacturers as well. "We have been
studying the market and trying to understand the potential for these
products," relates Stanek. "We have been active in the
study of biodiesel, such as soy diesel. We're looking at these
alternatives to understand what impact they have on engine life
and performance. Although we've not pursued the alternative
fuels at this point in terms of the market, we are investigating
these alternatives in the event that the market demand should dictate
sufficient need for them."
According to Norton,
"Diesels are going to survive for a long time. There are technologies
evolving right now that are going to make diesels as clean as natural-gas
engines. I don't think you'll find a diesel engine manufacturer–at
least for heavy-duty off-road–that wouldn't tell you that
their main focus is to continue to improve the diesel engine for
low emissions in the future as well as to manage the performance
and cost. The bottom line: giving the customer the best value."
The Importance of
Training
With all of these current
and proposed technology advancements, do contractors have to have
an engineering background to select the right piece of equipment
for their particular needs? The answer is simple: continue to rely
on the dealer networks and the personal research that has always
gone into the selection of equipment. "When we introduce new
products with new engine or machine technology, prior to launch
of these products, we set up a series of dealer training sessions
at the regional and local levels," says Stanek. "We bring
in representatives of the dealers and dealer network to be able
to understand what's improved, how to service it in the long
term, and how to troubleshoot it. All of the information that is
out there on engines is handled prior to product launch so that,
when the product is launched, our dealers can be poised and have
the tools in place to service the products as they're required
to do so."
"It's our responsibility
working with our first-line customer–the original equipment
manufacturer who is designing that backhoe–to make sure that
we optimize our engine to work effectively with that piece of equipment
and to allow the equipment to do its job," states East. "It's
really hard for the contractor to compare two engines, particularly
if it's across brands of equipment. There are so many variables
that go into how productive that piece of equipment can be. [Contractors]
need to focus on the engine and the way it's mated to the piece
of equipment. The other things they need to look at are: Do they
have familiarity with the engine and the components? Do they know
who their dealer distributors are when they need customer support.
I think it's between us and the equipment manufacturer to make
sure that engine's optimized to work well, but then I think
there's a direct personal touch of customer support after the
sale that's very important. That's one thing they need
to be very cognizant of when they're making equipment selections."
Guest author Lynn
Merrill is director of public services for the City of San Bernardino,
CA.
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