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When it comes to earthmoving
versatility in tight surroundings or wide open spaces—whether
topsoil or solid rock—excavators lead the pack. However, smart
contractors know that good operators and the right tools for the
job make a big difference in those machines’ overall cost and
performance—and in finishing the job on time and within bid.
But excavators aren’t
cheap. Ask Dan Baker, owner of Blue Iron Inc. of Stockton, CA. He
says, “I sold my ski boat 19 years ago for $7,000 and rented
a Komatsu excavator because I knew if I was going to be in excavation
I couldn’t get a job without an excavator.” After just
one month of renting he became an owner/operator. It took nearly
five years to pay for the machine, but by then he was prepared to
hire his first employee. He took on another employee three years
later. Today, Blue Iron has eight Kobelco excavators and 17 employees,
and last year completed more than $10 million in digging contracts
in the Stockton area.
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Photo: Movax |
In regard to what prompted
his brand selection, Baker comments, “Excellent dealer support.
Tri-West Tractors in Livermore, which is just 30 miles from headquarters,
is a real good dealer, very knowledgeable and helpful. When there’s
a problem, all it takes is a call and he has someone there who can
help, someone who knows the machine.”
On the other side of
the equation are the right tools. Since shoring is necessary to
prevent walls from collapsing, his company has the largest pile
driver mounted on an excavator on the West Coast. “It’s
a 100-ton Movax, which can drive piles in pairs, not singly. I had
a 50-ton, but took on the larger machine and the time it saves is
absolutely incredible.”
After commenting that
excavations can be as much as 45 feet, with large excavations removing
as much as 300,000 cubic yards as well as dealing in tight spaces,
Baker reports the 70-foot-long excavator boom and arm makes it possible
for his operators to reach deeply. “Last year, one of our jobs
involved an underground addition to a campus center at a hospital.
There were a lot of fiber optics and shoring was very difficult
because of tight quarters between additions. For shoring, we soil-nailed
to avoid caving in. Then we used a Rototilt so we could drill within
1 degree of whatever angle was needed for permanent shoring. That
tool made the difference between being able to do the job and not
being able to do it.”
He adds that there was
some digging by hand and they used a vacuum truck to help remove
solids. But it took operators just a day or two to become comfortable
with the rotating device. “It’s a user-friendly tool,”
he comments. “It’s taken a little bit of luck and a lot
of hard work to get this big, but I really enjoy what I do.”
Mike Meehan, Movax product
manager for Hercules Machinery Corp. in Ft. Wayne, IN, adds that
using the vibratory hammer to start pile placement eliminates the
need for a lot of overhead space. “The vibratory hammer holds
the pile by its side and can stick the pile into the ground until
it stops. By then it’s deep enough that the operator can easily
switch to the hammer of choice and finish driving it home.”
This includes placing piles approaching 100 feet long within 1 degree
of plumb.
He points out, “One
contractor used a small excavator on a waterfront project on residential
property, versus a crane which takes a lot of support equipment.
In Miami, where there are a lot of canals, another contractor had
a project dredging sediment buildup. After dredging, the sides of
the canal started to cave in, and those sides were right next to
the road.” That’s when the contractor used sheet pile
and backfilled the whole length of the road. It took three months
to install 1,000 feet of sheet pile 25 feet deep. “They used
the Movax 100% of the time and no conventional hammering was needed.
While you get noise from vibration when interlocking sheet steel
columns, you don’t have the intense noise associated with conventional
hammering.”
Meehan agrees with Baker
regarding the advantage of getting as much size as possible. “Movax
was imported to the US in May 1998, and we’ve since bought
the manufacturing rights for the Western Hemisphere. Since 1999,
we’ve sold and manufactured over 100 units for the domestic
market. It’s in a constant state of improvement. We’ve
taken it from a 50-ton machine up to 100 tons. We’re making
it bigger, stronger, and harder so it can provide more and more
energy to accommodate a wider variety of projects.”
Other New Tools
Baker’s latest tool addition came from Sweden, through North
American Hydraulics Inc. of Baton Rouge, LA. Dennis Buquet, Rototilt
manager for the US market, reports that while the Swedish-built
Rototilt has been in the European excavation market since 1987,
it has been in the US a mere three years. He also reports, “It’s
used in many applications, from railway maintenance to golf courses,
foundation work, underpinnings, inner city projects, and in places
where you’re dealing with transportation, people, and traffic
issues. It makes it possible for an excavator of any brand to work
more closely to itself.”
He adds that, most of
the time, an order can be filled within two weeks. “The absolute
worst case is six weeks on an oddball, ancient machine that’s
not a big player in the market.” As for ease of operation,
he says learning may take as few as four hours. “With continuous
rotation and side-to-side tilt, the operator can use it as an extension
of his wrist. And with the attached hydraulic quick coupler, he
can quickly and safely change from one bucket to another without
having to get out of the cab and put in a safety pin.”
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Photo: Link-Belt |
Enhanced Excavators
Today’s excavators are more comfortable, more economical, and
more versatile than earlier versions. When you consider the added
versatility, they’re easier to operate than ever before. “The
biggest change in the last decade has been in auxiliary hydraulics,”
says Chad Bixby, underground utility product specialist for Caterpillar
Inc. in Peoria, IL. “That change allows machines to have different
flows and pressures for different attachments. Hammers have different
requirements than shears, thumps, or rotators. When you design auxiliary
hydraulics you want to make sure the combination of booms and sticks
will have the proper structure designed to handle the different
tools. For instance, you don’t want to design the stick and
boom so it’s too heavy when using a hammer, because of possible
problems with the machine tipping.
“Excavators are
doing many more functions and the integrated hydraulics and electronics
allow the operator to switch between widths of attachments automatically
and pick up different attachments without getting out of the cab.”
Bixby then gives the
example of digging a trench with a wider bucket, switching to a
toothed one to get through hard surfaces, then using a smaller one
where the pipe will lie, and finally, once the pipe is bedded properly,
using a clamshell bucket to fill in the trench. “Depending
on application, versatility of today’s machines has boosted
excavator productivity 30% to 40%. Contractors need fewer machines
on the job site. You want the job site running efficiently because
there are narrower and narrower margins on bids, yet contractors
need to make each job profitable.”
One way to do that is
to avoid getting out of the cab, yet know where the bucket really
is. Kristjan Ingvarsson, founder and president of Ocala Instruments
in Orlando, FL, says that excavator depth monitors can now be connected
to a GPS system to display the exact position of the bucket, whether
digging a basement, a trench, or a perfect embankment slope. “However,
using a rotating laser and inclinometer-based depth monitor gives
the highest precision in depth measurement and minimizes calibration
drift. So if precise depth is the job’s main issue, the instrument
of choice is a depth monitor rather than a GPS-based system, at
a fraction of the cost.”
Ingvarsson reports the
newest enhancement of Ocala’s product line is the Ocalaser.
It is a laser receiver that mounts on the dipper stick and automatically
relays the laser height to the depth monitor inside the operator’s
cab. This makes the reference level exact to within 0.02 feet. He
comments that not only can the instrument measure depth, but embankment
slopes, distances around the excavator, heights, etc. “One
of the nice things is that it will indicate the bucket opening when
digging under water. This ensures a full load in every scoop. Some
very difficult measuring tasks are easily accomplished with an excavator
depth monitor, such as digging a perfectly vertical wall, or a perfect
slope under water.”
Is Your Excavator
Ready for 2006?
Matt Hendry, product consultant for excavators and articulated dump
trucks for John Deere in Moline, IL, adds that manufacturers have
been prepping their machines so they will meet federal Tier 3 emissions
standards coming out in 2006. “That’s going to drive a
lot of end users to replace existing machines,” he predicts.
He also notes that operator comfort plays a larger and larger role
in excavator design. “It needs to be comfortable and it needs
to be simple.”
Add efficient electronics,
efficient hydraulic oil flow, and even higher performance engines,
and an operator is able to move more dirt in less time. “That’s
because today’s excavator lets the operator work deeper into
the rpm curve before the hydraulic pumps destroke, which means more
oil flow. More flow means more productivity. Today, using very efficient
pilot controls requires much less operator input and efficiently
manipulates the hydraulic pump. Operator movement is greatly reduced.”
He reports that—compared
with a decade ago—excavators are 10%–20% more efficient,
and can expect more than 8,500 hours of use before any major component
problems. This will vary greatly depending on how the machine is
cared for.
Then, after citing the
creature comforts that enable an operator to maintain productivity
throughout the day, Hendry comments that more and more machines
are using quick couplers to make tool transition faster. “When
it comes to trenching, the bottom line is the more pipe in the ground
the more money. The only way to make money is to utilize attachments
that boost efficiency.”
He recalls a subcontractor
in Colorado with an excavator. The project involved a 5,000-square-foot
historic home that had to be 75% demolished—without harming
the other 25%. This included removing the linoleum without damaging
the sub-flooring. The main contractor had booked 30 days for his
crew to handle this sensitive work by hand. Then he learned of the
excavator operator and had him come onsite. That individual demolished
the designated portion, loaded the material for trucking offsite,
and even switched from a toothed to a smooth bucket to gently scrape
up the linoleum, and finished the work in less than eight hours.
“He did that early in the spring, which opened up the whole
working season to the contractor. A hydraulic excavator is the most
efficient digging machine in the industry, and the growing trend
is to use it 30% to 40% of the time for aboveground application.”
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Photo: Daewoo |
One example is a project
that involved several different firms in Fairbanks, AK. The Alaska
Pipeline stretches 800 miles, is 4 feet in diameter, and has portions
that stand 10 feet above ground. That’s when the whole pipe
is exposed to elements as well as potential vandalism, resulting
in difficult repairs in hostile weather.
Determined to make repairs
easier and faster, Alyeska Pipeline Service Co. contracted with
Holaday-Parks Inc., a Seattle-based sheet metal ventilation and
fabrication company that has had a division in Fairbanks since 1970,
to build a clamp that an excavator could apply to the damaged area.
Jerry Mustard, P.E., mechanical engineer for Holaday-Parks in Fairbanks,
explains, “We have three main parts to the business: ventilation,
including commercial, industrial and residential; walk-in work,
when people walk in and ask us to fabricate special items for them;
and metal pipeline insulation jacketing for the oil industry.”
They were asked to design
and build a clamp that would stop an oil spill temporarily but quickly
so the service company would have time to shut down the line, drain
the fluid, weld the damaged area shut, and then reopen the line—without
having to struggle to do so during extreme weather conditions.
Mustard continues, “I
was the project manager and our sheet metal mechanics were the chief
fabricators, with Stanley Hendrickson Jr. doing most of the work.
Crisenbery Engineering did the machine design work, Hydra-Power
Systems Inc. of Portland, Oregon, designed the hydraulic manifold
inside the box that’s part of the clamp, while Boyd Turner
of AES Electric handled the electrical work, and George Sundborg
and his crew at Sunel Equipment helped with the hydraulics.”
They began the project
in July 2002, tested it in the summer of 2003, used the following
winter for refinements, and retested it last summer in Alyeska’s
yard in Fairbanks, and the client took possession of two 1,200-pound
clamps in December 2004. Part of that testing involved a Cat 320
excavator and a Rototilt, both of which Holaday-Parks altered.
“The clamp opens
up hydraulically; the excavator places the clamp on the pipe and
positions the 4-inch ball valve over the hole in the line before
closing the clamp by engaging the latch hook. Then the O-ring hydraulically
forces the aluminum plate against the pipe. After that, it’s
a matter of closing the ball valve to stop any flow. A skilled operator
can complete the whole procedure within 10 minutes after getting
the excavator in position to do the work.” An operator and
spotter are all that’s needed for clamping the pipe.
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Photo: Ditch Witch |
Swinging in Tight
Spaces
While attachments have helped excavators compress operating space,
Scott Sutherland, product manager for LBX Co. LLC in Lexington,
KY, still sees a need for mini-sized machines. “Excavators
are becoming more of a mobile hydraulic platform than strictly an
excavator. Smaller machines have become particularly popular in
two markets: forestry and scrap handling. The Chinese really created
a supply shortage for steel, and with the 30% to 100% boost in prices
for scrap, whether it’s T-1 or just rebar quality, more mini-excavators,
such as our Spin Ace, are in demand.
“Space is getting
tighter and tighter. There is a lot of need for a minimum swing
radius so operators don’t have to worry about damaging the
machine or be concerned about the safety of people on the ground
behind them. Like the larger machines, they can handle breakers,
buckets, and quick-attach couplers.”
Like its bigger brothers,
Link-Belt’s 80 Spin Ace Swing Boom Excavator offers operator
comfort as well as ability to handle rough terrains. Plus, the hydraulic
system is kept clean for up to 5,000 hours through the use of Nephron
filtration, which filters particles down to 1 micron in size.
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Photo: Komatsu |
Finding the Right
Tools
As a tool supplier for smaller machines, CEAttachments Inc. in Cedarburg,
WI, offers nearly 2,000 items organized into 70 different categories
on its Web site. “We supply tools for excavators up to 12 tons
in size,” explains Sarah Bemowski, sales and marketing specialist.
“For excavators, the three lines in greatest demand are buckets,
thumbs, and quick-attach couplers. Other hot items include augers,
breakers, compaction tools, grapples, and rippers.”
She says that buckets
can include standard smooth and toothed buckets, cemetery buckets,
tilting buckets, and quarry rock buckets, as well as those for even
more specialized uses. “Our smallest bucket is an 8-inch and
has 0.75-foot capacity. It is especially popular for utility piping,
for smaller excavators up to a 3.5-ton machine.” Their larger
buckets can hold as much as 13 cubic feet.
Bemowski reports different
styles of buckets have started to become more popular for smaller
excavators. Use often is more diverse than the name may indicate.
CEAttachments’ cemetery bucket, for example, also is used as
a general trenching tool. With thumbs, operators can more easily
handle rock, brush, and small logs, as well as other objects that
wouldn’t fit into a traditional bucket. “When we get an
order for a thumb we have to know the make and model of the excavator
and whether it will be used with a quick coupler. We also need to
know the pin size to make sure the thumb will work well with the
specific machine.”
She comments that attachments
usually are an afterthought. “Often, a contractor needs an
excavator with a bucket, then the next job may call for an auger.”
This means CEAttachments keeps a full line in its 25,000-square-foot
warehouse, making shipment to the dealer possible within just two
days. “We have about 60 suppliers for our inventory.”
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Photo: Blakeman Construction |
“Bells and Whistles”
After commenting that a vast majority of customers are running standard
excavators, Carl Heggen, product manager of hydraulic excavators
for Komatsu America Corp., adds, “Komatsu excavators come standard
with some pretty high-tech features: equipment management and vehicle
health monitoring systems (EMMS/VHMS), Komtrax tracking systems,
Orbcomm satellite monitoring system (PC1250 and PC1800), viscous
cab mounting, automatic climate-control heater/AC systems, computer
management systems for engine and hydraulic control, advanced engine
emission controls, advanced hydraulic filtration systems, and more.
“When you get into
specialty applications, this is where the added bells and whistles
come in.” This includes demolition attachments, such as shears
mounted to either stick or boom; long-reach boom/arm arrangements
with grapples/buckets/etc.; hydraulic breakers; and concrete crushers.
Special material handling attachments provide the excavator with
the capability to load and unload barges at dock facilities and
efficiently handle the needs of waste recycling and transfer stations.
A wide variety of magnet and grapple attachments are available for
scrap iron. In these applications, excavators tend to be equipped
with long-reach front ends, elevated cabs, additional cab guarding,
and special hydraulic packages.
Heggen says, “Typical
working tools are grapples, clam buckets, and buckets with thumb/bale
arrangements. Many units will have hydraulic tool rotation and material
handling, and scrap iron units are often mounted to a stationary
pedestal base. Outside of our main construction and mining markets,
others are steadily moving to excavators as a productive, versatile
way to solve their material handling needs.”
For instance, the logging
industry offers opportunities for specially equipped hydraulic excavators
due to speed, stability, and ability to work in confined areas.
Heggen reports there are a wide variety of attachments for that
industry. These include feller/buncher heads, processors, delimbers,
and stackers with special guarding packages to protect both operator
and machine from falling timber. “Excavators are also sold
for lumber processing yards and paper mills to sort and stack incoming
timber. These units are often pedestal-mounted and have various
configurations with hydraulic rotators.”
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Photo: Blakeman Construction |
Adverse Weather Conditions
The fleet for Blakeman Construction in Shelton, CT, includes eight
excavators ranging in size from 3- to 50-ton machines. Owner Monty
Blakeman notes he started the company in 1966 and now does $10 million–$15
million per year, chiefly in housing construction. And that will
be anywhere from 15 to 30 homes per year. “We do nearly all
of the work ourselves, from selling the trees off the land before
digging to trenching for utilities to building the homes to preparing
the lots for landscape features. The only thing we regularly sub
out is the paving.”
In 2004 he started a
15-acre shopping area and his crew is in the process of moving 150,000
yards of rocky soil, with some cuts going 30–40 feet deep.
“My favorite tools include rock hammers, compactors, and quick
couplers. Articulating buckets also are very handy. We’re working
with raw land and with existing structures.” So they’re
prepared to handle the different challenges, including getting around
those structures and quickly handling excavation chores.
Another challenge is
the weather. “We’ll lose approximately two to three weeks
total during the winter season because I don’t like to work
a machine when it’s much colder than 15 degrees. We use treated
fuel and obviously try to keep the tracks clean so overnight freeze-up
is not a problem.” He comments that frost can go as deep as
3–4 feet, but the operators quit digging when the frost goes
beyond 12–14 inches.
When asked what he likes
best about changes in excavators over nearly four decades, he responds,
“I think it’s the conveniences. Hydraulics are so much
faster; the cab is more comfortable. Our newest machine is a year
old and it already has 1,450 hours on it. Operators work more efficiently;
we get more production because of the comfort and balance of the
newer machine.”
Walter Reeves, excavator
product manager for Volvo Construction Equipment in Asheville, NC,
comments, “The excavator today is more of a tool carrier than
anything else. Hydraulic-driven attachments and quick couplers are
two of the most popular tools for work. Our excavators are designed
to handle a multitude of different tools, including material handling
buckets, trenching buckets, hydraulic hammers, and hydraulic angle
buckets.”
Reeves, who has been
associated with the construction industry for 30 years, adds that
when it comes to size, Volvo excavator users tend to choose the
21-ton and 29-ton machines. “They’re used in every possible
site you can imagine, from pipe and utilities to land improvements,
as well as industrial and residential building.”
In the 13 years that
Volvo has manufactured excavators, machines have gotten quicker,
more user-friendly for attachments, easier and more comfortable
to operate, and more fuel efficient. “With machine hydraulic
advancements and tool design improvements, users are getting 25%
to 30% more efficiency out of their excavators. Dozers used to do
a big share of dirtmoving; now they’re being used about 50%
less than before because the excavator can do more of the work.
In many instances, excavator utilization is way up while dozer application
has diminished.”
Reeves points out, “There
is less and less requirement for the service mechanic to come and
modify the machine to run different attachments as operators can
make these adjustments from the cab. Contractors are able to do
more work with fewer machines, but on the other hand, since they
can do more work with one machine, a company can do a lot more work
when it has more than one excavator in the fleet.”
Looking to the future,
he says, “Right now, Volvo does not supply tools, as we will
in the future. We let the user and his dealer decide on the attachments,
while we give advice and supply the information that helps the individual
contractor determine his needs for his particular operation. After
all, it’s more cost-effective to buy the machine and necessary
tools at the same time than to purchase a stripped-down model and
add the tools one at a time.
“The market for
excavators will continue to grow as people find more utilization.
They’ll be lighter, more fuel efficient, and offer higher production.
In terms of cost per ton of material removed, excavators will become
even more cost-effective.”
He also agrees that buying
a machine with a major component life cycle of a minimum of 8,000
to 10,000 hours is less expensive in the long run than buying a
less durable excavator. “Engines with higher torque and lower
rpm give you a more fuel-efficient machine, and fuel efficiency
will continue to play an important role in operating costs. With
the right tools, users will get even more utilization than they
do today.” So it is that excavators make it possible for contractors
not only to succeed today but to envision an even brighter tomorrow.
Author Joseph Lynn
Tilton writes frequently on construction-related topics.
GEC - March/April 2005
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