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Contractors World - International Vol 3 No 8
supported by the best dealers in the world. The 336E H extends our
leadership, is the right thing to do for our customers and is a sign of
great things to come.”
Some bold statements, some of which Contractors World
question for reasons mentioned in the introduction. The emphasis,
initially will be on fuel saving, but will gradually change from lower
fuel consumption to emissions with regulation dictating their use
regardless of cost.
And, of course, the fuel saving is only achievable if the application
is one in which there is significant swing activity as this is where the
hybrid’ energy comes from.
Proven excavator series
Since the introduction of the 300 Series in 1994, the family of
excavators has become the industry standard in a large variety of
general, quarry and heavy construction applications. Caterpillar
introduced the standard 336E in 2010 as a direct replacement for
the 336D. The 336E was introduced primarily to meet Tier 4 Interim/
Stage IIIB emissions standards, and like any new Cat machine, it
includes several enhancements over its predecessor, including more
horsepower with greater fuel efficiency, more lift capability, higher
digging force and automatic after-treatment regeneration.
The 336E H has all of the same powerful advantages of the 336E
with the biggest difference between the two models being even
greater fuel efficiency. To achieve added fuel savings, the design of
the 336E H uses three building block technologies that:
1.
Conserve fuel with engine power management via the Cat Electronic Standardized Programmable (ESP) pump,
which smoothly transitions between the hydraulic hybrid power sources, engine and accumulator.
2.
Optimize performance using restriction management via the patented Cat Adaptive Control System (ACS) valve,
which intelligently manages restrictions and flows to seamlessly control machine motion with no loss of power,
and to ensure operators experience no difference in control, hydraulic power or lift capability.
3.
Reuse energy via the hydraulic hybrid swing system, which captures the excavator’s upper structure swing brake
energy in accumulators, and then releases the energy during swing acceleration.
Less Fuel = Lower Emissions = Green Technology
The 336E H delivers up to 50 percent greater fuel efficiency, which is measured in tons per liter, over the 336D. Customers
can expect the 336E H to use up to 25 percent less fuel compared to a standard 336E, and up to 33 percent less fuel than
the 330/336D.
All three of the technology building blocks are integrated together to maximize fuel savings in a variety of
applications. Even in low-intensity swing applications, customers will still experience significant fuel savings because of
the technologies.
It also has to be stated that additional factors, such as operator skill and jobsite conditions, also affect fuel savings.
Return on Hybrid Investment
Precisely when customers will recoup their initial investment in a 336E H depends on fuel prices and their applications.
Assuming today’s fuel prices and a high-production application for a 336E H, Caterpillar estimates customers can
realistically expect to see a return on their investment for the hybrid excavator model in as little as one year.
Customers have been using field follow machines, which are first production machines built for customer acceptance
testing, to validate fuel burn, controllability, reliability and performance.
In a formal production study completed in August 2012, results were impressive, including greater fuel efficiency, and
lower cab and spectator noise levels than the 336E and 336D.
Additionally, the ACS valve, which intelligently manages restrictions and flows to seamlessly control machine motion,
has been in the field since 2008 with superior performance and reliability. The ACS and hybrid system have also proven to
work well together to maximize performance and controllability of work tools, including hammers, shears and grapples.