Posted on 06/12/2009 7:19:45 PM PDT by Ernest_at_the_Beach
This big dozer, the Caterpillar D7E, is the first to use a hybrid power train.(Credit: CNET)
On the way to a demonstration of Caterpillar's first hybrid dozer, I was expecting it would be one of the little ones, the kind used to dig pools and landscape suburban back yards. But looming up in the middle of Holt of California, a Caterpillar dealer outside Sacramento, Calif., was a huge beast, a massive yellow earth mover, the metal tracks of which came up to my waist. The Caterpillar D7E was a lot bigger than the little hybrid I was expecting.
A Caterpillar representative jumped in the cab and, metal tracks scraping up the clean concrete floor, pivoted the big dozer around and drove it out to the demonstration area, a field of dirt with one big hill, and strategically placed holes and trenches--not to mention a slalom course marked by orange pylons. As a dramatic start to the demonstration, the driver took the 56,669 pound D7E over the steepest section of the hill, the dozer's blade pointing up toward the sky. At the top, it neatly balanced on the crest before making its descent, demonstrating how easily it maintained control on this loose ground.
The D7E differs from traditional earth-moving equipment in that it uses a locomotive-style series hybrid drivetrain.
(Excerpt) Read more at reviews.cnet.com ...
fyi
D7 is nice but the D9 is a sight to behold
>The D7E differs from traditional earth-moving equipment in that it uses a locomotive-style series hybrid drivetrain.
Diesel Turbines! Nice.
Hybrid my 0bambi, I want to see a carbon belch!
No, it is a conventional engine, but the dozer has electric drive motors. The diesel powers a train style generator.
Maybe the electric drivetrain is more efficient, but wouldn't the hydraulic drivetrain be a "hybrid" too?
R.G. LeTourneau (LeTourneau, Inc.) built some of the largest earth moving machines in the world. The old man was fanitically opposed to the use of oil hydraulics and insisted that his machines use electric motor powered winches and cable for all the actuators. That extended to the propel drive train as well. He was so biased against oil that he swore that if there was a way to run an internal combustion engine without lube oil, he's do it. After the fonder retired they slowly integrated oil hydraulics into their machines. Many of the huge open pit dump trucks also use and electric drive as well.
Regards,
GtG
The Hi Track, up drive sprocket a thing of the past?


BIG “oop-si-daisy”
So is this thing.
I would love a diesel / electric hybrid 1-ton pickup.
Unfortunately, such a thing cannot be made (or can easliy be modified not) to abide by the speed limits.
Consequently, it will never happen.
Those excavators are amazing. Plus, everything about them is politically incorrect. I mean, they’re STRIP MINING machines for gosh sakes. They mine for that nasty coal that iBama wants to ban.
RG also built the tourna train consisting a string of trailers with an electric motor in each wheel for snow, mud etc. Mercedes also builds diesel electric tractors, bushhogs having electric motors instead of power shafts. RG also put every thing on Rubber. after he sold the company to Westinghouse Air Brake, he developed land clearing machines that mowed down trees. He also had a machine that carried a one BR house made of concrete and set it on a foundation. Amazing man RG, self made, uneducated, a welder by trade. The Earthworm tractor company is searching for Obamadollars convincing the pols that they invented Hybrid earthmoving. BTW I got a letter from Obama Motors saying the Pres was going to take care of mei and offering a $2500 discount on a new Sub. I dont think so unless I bought it from a screwed over dealer
barbra ann
But General Electric and EMD have developed Hybrid's that have banks of batteries in them that Store the electrical power into them.. then are applied to the traction motors as the engineer directs.
But this is all new stuff.. and I only have heard of the BNSF Railway experimenting with one or two switchers with this technology.
But, but Obma told the mining communities he loved coal and was committed to clean coal technologies...
Glass Engines, Remember the Vega and teflon lining in the cylinders. HF also built with fiberglass.
barbra ann
Diesel driving a generator driving the traction would be.
The dirty little secret is âhybrid drivetrainâsâ are hundred year old technologies
Oh GMAFB
Cooool.

Now that's my idea of a roto-tiller.
The Diesel drives a Alternator producing electrical power to the traction motors in a regular Diesel Electric Locomotive. When the Engineer operates the throttle.. the Diesel engine engages..produces power that goes to the traction motor on the wheels.
A Hybrid version would be.. the Engineer engages the throttle.. which produces power which goes to the traction motors initially.. but also charges the banks of batteries. When the engineers needs the power he can apply to the engine such as in the GE Evolution Locomotive.. Or in a present switcher.. the batteries is what is charged and the engineer engages the throttle to run the traction motors from that bank of batteries..
Links below: http://ge.ecomagination.com/products/evolution-hybrid-locomotive.html
http://www.tc.gc.ca/programs/environment/ecofreight/casestudies/images/idc2-eng.gif
Clean coal = no coal.
I anyone had said we were riding a hybrid there would probably have been a fight.
R.G. LeTourneau, industrialist and inventor powered his mighty earth moving scrapers “Tournapulls” with electric motors on each wheel. The unit was steered by a central electric motor between tractor and scraper. Incredible engineering from an incredible man.
As a talented engineer/physicist I invented a perpetual motion machine, just like ALgore invented the internet. Now .. if I can only figure out how to get it started .......
Sorry about that, post #33 was intended for tube.
I know about KeTourneau and I'm in central Illinois....Caterpillar country.
I have a LeTourneau Westinghouse road grader :)
This isn’t a “hybrid” it is a diesel-electric, the same drive they use in Locomotives. The diesel engine runs all the time, not just when the batteries run down as happens in a hybrid car, the diesel runs a generator which is used to power the electric drive motors. Old technology.
LeTourneaus are used every where. When the lumber mill in my area used to operate(from 1945 until 1998, when the greenies caused it to be shut down and 650 jobs lost), we used LeTourneaus to haul logs from the log decks to the mills and to off load the tucks and stack the logs. Huge puppies and fun to drive.
Where are the solar panels to power that bulldozer ? ( Sarcasm ) ...
Turbines?????
LOL!
Actually no, I'm an ex-logger from northern Wisconsin who went off to college and got two engineering degrees. We had our own R.B. in Baraga UP Michigan. Pettibone was cut from the same cloth.
Regards,
GtG
The dozers are conventional, but I know the large dumptrucks are electric wheels with diesel/electric generators under the "hood".
The largest cable shovels and draglines are all electric connected directly to the grid with a big flexible cable drug along by a dozer.
I don't know how glass would work out as it is actually a "super cooled" liquid which gets softer as the temperature increases, it doesn't actually melt (go thru a phase change) at any particular temperature.
I had heard about GM working with high strength ceramics which have very good high temperature characteristics and can take compressive loading in stride. The down side is they are very brittle and are lousy in tension. I know they got some demomstration "proof of concept" prototypes running but what happened after that I lost track of.
I worked for a hydraulics firm that built vane pumps. We also tried ceramics for pumps that ran fireproof fluids as they generally have low lubricity. We found that it could work if a ceramic ring was shrunk fit inside a steel ring. That left the ceramic under a large compressive loading much like tempered glass. The problem was the vanes that slid along the inner surface of the ring. We tried just about every tool steel and heat treat we could think of up to titanium carbide but the wear rates were uniformly unacceptable. When you really think about what we had invented was an "inside out" grinding wheel which ate up the mating parts as fast as we could shove them into the pump!
Some things just aren't meant to be...
Regards,
GtG
Why don’t they just run it on used french fry oil?
Ferdinand Porsche invented that type of drive train for his version of the Tiger tank. It was a bust, but he was pals with Hitler, so they built 100 of them anyway.
What a laugh...a D7 huge????
Try an 11.
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Caterpillar D11
D7 always impresses me as being in the upper range of medium duty. The D9 is what turns my head.
I've never seen a D10 or D11, I can only imagine the tingling sensation that would run up my legs at the sight of one of those behemoths.
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