Electric (Tonka) Dreams

Andrew Miles plays with his trucks.

The sports truck does its thing… (c) Liebherr

I was five years old that Christmas when the bright yellow truck arrived – chunky tyres, opening doors and that tipper truck action – get me to a sand pit, now! Tonka toys were large, usually painted bright yellow and virtually indestructible. Since that time my interest into the real-life enormous dump truck has never waned. 

Think electric power is the preserve of cars future? Think again…

The Erzberg open cast mine, near the Austrian town of Eisenerz, is roughly forty miles northwest of Graz. They found stuff to mine here 1,300 years ago but of course it was by pick, shovel and hard, manual labour. Today sees twelve millions tons of stone mined every year to extract three million tons of siderite iron ore. That’s substantial shifting, leading to equipment of real life Tonka toy dimensions.

Where did the Alp go? Slim-project.eu

Diesel was the de facto engine choice for years. Huge torque, decent reliability but with lots of power sapping gear changes and questionable ethics which have only grown larger over time. Being over a thousand metres above sea level and constantly seeking better profitability, efficiency and reduced costs, German engineers, Liebherr used Erzberg as a testing ground for diesel-electric motion in their T236 100 tonne capacity dump truck.

Producing 1,200 hp (895 kW) means this truck with payload now weighing in at 180 tons can climb the six kilometres to the stone crushing station in around ten to twelve minutes, weather permitting. That’s some going and conducted with smooth, gear change free, constant speed, keep your foot down and avoid the tiny cars somewhere down there – easy.

Blasting the rock occurs twice a day. Four shifts work constantly around the clock, the ceaseless greed of the crusher forever hungry for more. The T236 (does the T denote Tonka?) has only been operational about eighteen months now, the remainder of the fleet, for now still on pure diesel power. But changes and improvements are ongoing. 

(c) Liebherr.com

Shifting this amount of weight by these means means the T236 is a European first. Constant power driving the rear axle and extremely smooth initial starts lead to those all important factors of less wear and tear, less breakdowns, maintenance and therefore lower costs. Manna from heaven for the giant mine’s operators. 

Once those one hundred tons of rock payload are gone, another load has to be collected. Downhill and empty, you still have eighty tons of truck to slow down and stop – once more, electricity plays it’s part. Pressing the brake pedal draws on the electric motor. With assistance from the deceleration effect of the diesel engine, fuss free and virtually fuel free braking can be had. The truck also has huge, oil cooled multiple disc brakes to facilitate manoeuvring when positioning to the excavator and reversing toward the crushing area. 

Should this heavy lifting become all too much for you, the Erzberg mine can offer more soothing ways for the tourist. One can ride in a tourist- modified (diesel) truck of old and overtake a full laden machine. You can even watch them blasting the rock from a safe distance: Vienna, presumably. And get up close and personal with the Tonka truck excavators. Should the weather turn foul, perhaps a trip into the mine will satiate your needs? Travelling in a former crew katl rail based carriage, you can delve 1.5 kilometres underground where a local brewer has found these to be ideal conditions for his lager to settle and mature. Tasting is encouraged.

For those with more energy than the dump trucks can produce, the mine also holds sporting adventure days. Motor crossing, climbing, abseiling and marathons around the zig-zag courses are held in the summer, hopefully nowhere near live mining operations. 

Back to the trucks and that endless pursuit of lowering those Total Costs of Ownership, the clever folk at Liebherr have looked to other forms of powering their trucks. And their search led to trolley buses.

From November last year, an experimental truck along with 800 metres of overhead wiring has been operating on the mines roadways. The trolley poles are raised or lowered automatically with radar control. The supply is rated at 900volts DC. The pantographs have to be fitted to the trucks front on a large A frame but apparently causes little in the way of obstruction. Should these experiments prove successful, plans are afoot to fit an overhead network of 20km’s length.

And it’s not just in Austria where trolley bus style pantograph mechanisms are being used in mining operations. A uranium mine in Namibia has this very same set up along with a copper mine in Zambia. Those machine are bigger too. Liebherr can offer the T264 whose payload of 240 tons means a gross vehicle weight of 416; not big enough? Then the T284 is the one for you. This beast has a 363 ton payload making a heavyweight total of 600 tons full laden. None of these trucks are suitable for narrow lanes, bridges or trips to the supermarket. And you’ll still need plenty of diesel to run them. 

Going up… (c) Liebherr.com

Tonka toys then are alive and well and positively thriving on their diet of electricity. My only concern being why the Erzberg truck is mainly white over a splash of yellow? I ordered yellow. I demand a refund; look, my boy has this big sand pit and…

Author: Andrew Miles

Beyond hope there lie dreams; after those, custard creams?

26 thoughts on “Electric (Tonka) Dreams”

  1. These mining dump trucks are somwhat out of dimension. The engine of the larger ones (MTU, optional Cummins) has up to 2,000 kW

    Many years ago a consulting job got me to Demag-Komatsu, one of Liebherr’s competitors, including a visit to their proving/testing area.
    It looked like an outsize sandpit and it was weird fun to watch trucks transporting more than 100 tons and diggers with more than 35 tons per bucket.

    Fun fact: the Liebherr company producing these trucks and fitting diggers is the same that is producing Liebherr fridges.

  2. Good morning Andrew and thanks for bringing us something really unusual. What an amazing feat of engineering! These huge trucks bring out the little boy (or girl) in those of us who love and see beauty in the precision of mechanical engineering. The engine featured in Dave’s photo is a lovely thing to behold.

    There will be, of course, environmental concerns about what these machines represent, the exploitation of the Earth’s resources, but unless we are willing to go back to living in caves, we have to find more sustainable ways of living, by way of science and engineering.

  3. Morning Andrew. What a great article although, from an environmental viewpoint, the machine that Mr Gatewood features is even more impressive or appears to be. Reminds me of the rides in the Unimog we have undertaken but on a far bigger scale!

    1. The battery driven dumper works only in this particular condition and nowhere else.
      Here it is used to drive downhill with full payload with recuperative braking used to generate the electric energy for the battery. The amount of generated electric energy is equivalent to the weight of the payload and the height difference of the downhill travel.
      The energy is just sufficient to get the empty truck back up the hill.
      As soon as there is any significant part of the travel running in a horizontal orientation it wouldn’t work and it also wouldn’t work in Eisenerz because here the trucks drive uphill with their payload and downhill empty.

    2. That’s interesting, Dave. So it works on the same principle as those peak-demand hydro-electricity generation installations where there are two reservoirs, one on top if a mountain and one at the base. When electricity demand is high, they open valves to allow the water to flow from the upper to the lower reservoir, driving generators on the way down. At off-peak times, the water is pumped back up.

      Such installations actually use more electricity than they generate, but the upper lakes acts as a giant ‘battery’, storing potential energy until it’s needed as electricity. All fascinating stuff!

  4. Down here in Oz in the North West,Rio-Tinto and BHP operate similar trucks in the large iron ore mines up there,but the difference is they are nearly all autonomous,controlled from Perth 1,500kms away.

  5. Hello Andrew,
    I have always been fascinated by these giants -although otherwise I am not much of a truck aficionado- and now thanks to this excellent article I know a lot more about them and how they work; thank you!

    1. I was forever borrowing The Observers Book of Commercial Vehicles from our local library, some truly amazing machines in there. Andrew, how would something as gigantic as these be delivered to the quarry though? They seem too big to be transported on normal roads.

    2. And here’s how to get a medium size MAN marine diesel to its destination:

      Same at Wärtsilä

    1. Locomotives are diesel-electric for the same reasons as these monsters because mechanical transmissions are impractical in these dimensions. Some locomotives have two speed gearboxes whose gears can only be changed at stand still (to switch between passenger and cargo train modes) and fluid couplings that work by filling or draining the hydraulic fluid to modulate power transmission. Diesel-electric drive trains are much simpler, smoother and more flexible.

  6. Thank you Dave, those pictures are amazing. It reminded me of something I read about the Saturn V rockets used for the Apollo moon missions, and that the limiting factor on the size of them, which set the parameters for the whole shebang, was the width of the canals used to transport the main body from the factory in New Orleans to the Kennedy Space Center in Florida.

    1. Completely off topic.
      These marine diesels are masterpieces of thermodynamic efficiency and the way they are designed is simply amazing, not just for the outsize dimensions.

      I had the opportinity to visit MAN’s Marine Diesel factory a couple of times.
      It is situated right in the dry middle of Germany at Augsburg (MAN= Maschinenfabrik Augsburg Nürnberg) and the engines have to be transported to the next harbour, which can takes severyl weeks because the trucks can only drive during night time hours.
      When they want to cast an engine block the necessary iron is heated up by electricity and they have to co-ordinate the casting with Augsburg City. On the day all traffic lights and all public lighting are switched off to save energy for MAN.

      The crankshaft weights 80 tons and pistons are delivered three on a truck from Mahle.

    1. It might be a silly question, but why would a marine diesel manufacturer site themselves in the dry middle of Germany?

  7. Some wonderful follow up pictures and info there, Dave, thanks. And thanks to everyone for the comments, these real life Tonka Toys have never failEd in staggering me. Such a shame for their environment impact

    To Mike Arnold, are these vehicles remote controlled? If so, they must be the ultimate Tonka Truck

    1. From ‘miningmagazine.com’:

      “Autonomous Solutions (ASI) and Liebherr Mining Equipment Newport News revealed that Mobius, ASI’s autonomous command and control platform, will be compatible with the OEM’s new autonomous-ready haul trucks

      Liebherr said it integrated with the Mobius protocols for its vehicle control interface instead of establishing a proprietary command and control platform on its own. Going with an open platform will offer flexibility to customers when integrating different autonomous vehicle types throughout a mine site, it said.
      “Liebherr’s vision of an autonomous haul truck includes an open interface that enables the truck to integrate to ASI’s Mobius platform. Liebherr’s autonomous vehicles can be controlled under an OEM agnostic command system for autonomous vehicles, providing maximum flexibility for their customers,” the companies said in a joint statement.
      ASI director of business development over mining Drew Larsen added that, by adopting the Mobius platform, Liebherr will differentiate its autonomous vehicles “by addressing the market need for interoperability and openness”.
      The company’s automation products are already on-board at Anglo American and Rio Tinto, as well as large companies in other industrial sectors, such as Ford Motor Company.”

    2. Hi Andrew
      Quote below from the Rio Tinto site
      “Autonomous haul trucks are operated by a supervisory system and a central controller, rather than a driver. They use pre-defined GPS courses to automatically navigate haul roads and intersections and to know actual locations, speeds and directions of other vehicles at all times. “
      The central control is in Perth
      A similiar scheme is now also used to control the enormous freight train transporting the iron ore to the port of Dampier.

  8. I didn’t think diesel-electric mining trucks are that new? The overhead power supply is an interesting concept though, which could be combined with a battery for maneuvering at each end to eliminate the diesel engine.

    Similarly the remote/autonomous trucks mentioned are remotely driven for the precise positioning at each end (maybe this has changed in recent years?), then autonomous from point A to point B.

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