Earthmoving equipment: how it’s changed
There are varying opinions as to what machines should be classified as earthmoving
equipment. A spokesman for Caterpillar said that almost their entire line could be
considered as such, from the high end — excavators and backhoes — to the low end
— dump trucks and loaders.
Other machines that fall in between are articulated trucks, wheel and track-type
tractors, and scrapers. The line is usually drawn at motor graders, which are capable of
light-duty earthmoving, but are used mainly to level and redistribute.
A cursory glance at any equipment literature from companies like Caterpillar and
Komatsu will tell you right away what they believe is the most important change in
equipment over the past few years — increased productivity. That’s usually
followed by greater operator comfort and safety.
Increased productivity is the result of many separate advancements. Caterpillar cites
more powerful engines with faster torque rise which allows the machines to respond quickly
to increased power demands. While this new generation of engines is much more powerful, it
nonetheless has a reduced environmental impact.
Caterpillar says their machines have been designed with reduced exhaust emissions that
meet worldwide standards through the year 2001, and Komatsu’s emission controls are
designed to minimize pollutant output. Strides are being made in noise pollution, too.
Komatsu’s PC128UU ultra urban excavator was engineered to generate "about as
much noise as the family car," according to Mike Murphy, product manager for the
company’s hydraulic excavators.
Electronic controls
Most new machines from equipment companies have electronic control systems that
optimize engine and transmission performance, as well as hydraulic system performance and
fuel consumption.
For example, at Caterpillar, the recently introduced line of mid-sized G-Series wheel
loaders feature electronically controlled planetary powershift transmissions. Each
transmission has autoshift capabilities to ease the burden on the operator, and electronic
clutch pressure control that smoothes shifts for greater operator comfort and longer
component life. The microprocessor-based controls also serve as diagnostic points to aid
maintenance technicians.
Companies often give their systems trademarked names, such as Komatsu’s HydrauMind
hydraulic control system.
Operator comfort
Several industry professionals have pointed out that good operators are getting harder
to find, and manufacturers stress that operator comfort and convenience are taken into
account in equipment designs, not only to make the operator’s job easier, but also
more efficient and productive.
New cab designs provide better visibility, reduced noise and vibration, and improved
comfort. New control systems require low operator effort while improving machine
controllability for both the experienced and inexperienced operator.
For example, Caterpillar’s R-Series track-type tractors offer Finger Tip Control
for precise, simultaneous one-hand steering and transmission control so that the operator
can work more easily in close areas and around obstacles. Their wheel loaders offer
Command Control steering that allows an operator to turn the machine completely with only
a quarter turn of the steering wheel.
Komatsu calls their operator designs Human-first Engineering. "Komatsu recognizes
that improving the operator’s environment can play a significant role in boosting his
productivity," Murphy said. "This human-first approach to engineering the
cabs...has produced numerous design advances that have enhanced overall comfort and
provided superior visibility."
Easier maintenance
Most new machines have electronic monitoring systems that provide constant information
on machine health to the operator. The systems provide stored information to maintenance
technicians, and service modes help them diagnose conditions quickly.
Machines are now designed for easier routine maintenance. On Caterpillar’s wheel
loaders, regular service points are accessible from ground level and site gauges allow
fast assessment of radiator coolant, hydraulic oil, and transmission oil levels —
without having to use dipsticks that can allow contaminants into sealed systems.
Other changes
In January, Glen Barton, Group President at Caterpillar, said, "The rental
business is another key area of growth for Cat. Our involvement in the rental business has
grown rapidly over the past 15 years in response to a changing marketplace that demands
more rental machines and power.
"Today, the rental business is responsible for 60% of all our North American
deliveries, and it’s growing significantly in other parts of the world, as
well," he said.
Komatsu’s Murphy also cited the increase in rental business. "The industry
change that is causing manufacturers and distributors the most consternation is the focus
in rental," he said. The emphasis in risk transference has necessitated the creation
of two different companies — Komatsu Mining Systems and Komatsu Utility Corporation
— largely as a result of the increase in rental business, according to Murphy.
As for trends in equipment, Barton said, "Articulated trucks have become
mainstream construction machines due to their versatility and ability to work in virtually
all weather and terrain conditions." Caterpillar began selling ATs in 1985 and
announced a new line (the E-Series) in less than 10 years.
Reprinted from Better Roads Magazine
April 1998 |
