An Awesome Game Changer

We caught up with the Doosan DX800LC-7 at the company’s Little Ponton Limestone Quarry in Grantham in Lincolnshire

When someone who has been in the industry for almost 40 years refers to a new machine as ‘awesome’ and a ‘game changer’ you are inclined to sit up and take notice. How was that conclusion reached? We’ve been finding out from Rob Jackson. He’s General Manager at Geo Quarries Ltd, and the machine he’s been talking about is the Doosan DX800LC-7, supplied by dealers Pioneer Plant, official Doosan Construction Equipment dealers for the East Midlands.

We caught up with the Doosan DX800LC-7 at the company’s Little Ponton Limestone Quarry in Grantham in Lincolnshire.  There, we saw it working at the quarry face, loading up a dump truck with newly extracted material to be sent to a crusher.

Rob Jackson has been working with excavators and crushing plants in many parts of the world, including Oman, since he was 16 years old.  Rob described what is Doosan’s biggest excavator at 80 plus tonnes as ‘the best investment we have made in the last two years.’

“It really is an awesome machine,” he says. “Most people might think the bigger the excavator and the harder it is worked the more fuel it will burn, but it’s quite the opposite with the Doosan, by a long way.”

Josh Coleman from Pioneer Plant reckoned the excavator’s average fuel burn was 33 litres an hour.  However, Rob has gone one better at 32 litres an hour and by way of putting that in context, he comments: “We have two 70-tonne machines, both different brands.  One was using up 48 litres an hour, the other 40 litres, so we are making a huge saving on the Doosan.  Especially given that diesel is around the £1.50 mark at the moment. That’s what I call a game changer.”

It’s also a game changer in another way, as Rob explains: “By using the Doosan DX800LC-7 which has been fitted with a heavy-duty MST rock bucket to dig out the virgin limestone and take it down to the crusher, we don’t have to resort to blasting, which is another cost saving. The Doosan is now doing the work of the two older 70-tonne machines.  It simply takes everything you throw at it in its stride. We are probably moving about 3,000 to 4,000 tonnes of unblasted rock on an average day.”

Geo Quarries Ltd was established in September 2015, with the main objective of producing and supplying high quality quarried aggregates to the construction sector across England and Wales. After searching and investigating various locations across the country, they found a location outside Little Ponton.  After extensive testing and geographical investigations, operations began at what became the Geo Little Ponton quarry. 

The company, which continues to heavily invest in plant and machinery, processes around 15,000 tonnes a week.  In addition, produces a range of innovative and much sought-after construction materials including aggregates, gabion stone, decorative aggregates, and GeoPave self-binding gravel.

For an 80-tonne machine, it is easy to handle, is very stable

and powerful, providing an all-round smooth performance

So, how does the operator find the Doosan? “He loves it. It is so operator friendly, with a comfortable, air-conditioned cab, very responsive controls and good visibility. For an 80-tonne machine, it is easy to handle, is very stable and powerful, providing an all-round smooth performance. He also benefits from noise and vibration levels which are remarkably low. His shifts stretch up to 10 hours a day, so having a good working environment is essential.”

That working environment includes a fully adjustable, high-quality heated seat with air suspension, well positioned pedals, joysticks and armrests, which all contribute to operator comfort and efficiency. A multi-function 8″ touchscreen displays all useful information in a visual and intuitive format. At a glance, you can check the machine’s status and settings, while Doosan’s unique jog shuttle switch gives you easy and precise control over all machine functions. The proportional thumb switches on the joysticks can be mounted horizontally or vertically, as the operator prefers, for optimal control of hydraulic attachments.

A full camera array is standard, comprising a front camera, two side cameras and a rear camera. The camera display is separated from the gauge panel and provides full visibility around the excavator and allows the operator to see a top-down view of the area outside the machine. This is combined with an AVM (around view monitoring) system as standard.

LED working lamps are also standard, providing up to 75% better illumination of the workspace around the excavator.  This ensures improved productivity in dusk and night time work and helps prevent accidents on site. As Rob says, what’s not to like about it?

High output engine, super smooth hydraulics

and faster working speeds provide best-in-class performance

With a heavy-duty undercarriage from Berco which has got larger sprockets to reduce the wear compared to competitor machines, the DX800LC-7 is equipped with the latest generation of Perkins engine. Exceptionally powerful – with high torque at low revs – the Perkins 2506J engine combines reliability and low environmental impact. This Stage V compliant 6-cylinder engine delivers 402 kW at 1800 rpm.

The high output of the engine is combined with a Virtual Bleed Off hydraulic system, with two hydraulic pumps which between them pump out 1000 litres of hydraulic oil per second, and a high system pressure of 343 bar, together contributing to the best performance in the 80-tonne market.  The machine, in fact, says Pioneer Plant, actually weighs 86 tonnes.

It also features Doosan’s D-ECOPOWER+ technology which utilises an electronic pressure-controlled pump within a closed centre hydraulic system to optimise productivity and fuel consumption, depending on the mode selected. You can switch between two modes – Boom or Swing – giving priority to boom or swing movements, respectively, so you can best match how you are using the machine to the application you are working on. 

Faster working speeds are ensured by the 2-spool Boom Down Regeneration system in the DX800LC-7, which also reduces fuel consumption. The 2-spool hydraulic system for the bucket cylinder also increases hydraulic flow and the working speed of the bucket, again reducing fuel consumption. It also has a boom/arm cylinder lock valve (anti-hose burst valve) as standard for increased safety, preventing accidents caused by hydraulic hose rupture on site.

Large guard rails are installed along with anti-slip steps and plates, for safer, convenient access to the whole upper structure. Engine parts can be easily reached via the top and side panels, while the air conditioning filter is placed on the side of the cab for easy reach. The filter’s cover can be locked and opened with the starter key.

Shut-off valves have been fitted on the pre-filter piping line and fuel tank drain piping to make servicing easier and prevent pollution from leakage. To make maintenance easier, the greasing points have been centralised; an automatic lubrication system is available as an option.

There are two large separated cooling compartments equipped with reversible fans as standard which increase the cooling performance and simplify maintenance. For extra accessibility and servicing convenience, all filters (engine oil filter, fuel pre-filters, fuel filters and pilot filter) are located in the pump compartment, while the hour meter display can be easily checked from ground level. A battery cut-off switch also makes it easy to disconnect the battery for long-term storage.

As Rob pointed out, the excavator came with a factory-installed state-of-the-art DoosanCONNECT wireless fleet monitoring system. “It helps me see how the machine is performing. I can keep track of fuel burn, of operating hours, how long it’s been on idle, what mode it has been in and much more,” says Rob. “Equally important, the boys back at Pioneer Plant can also keep track of how the machine is performing, noting any potential issues even before I become aware of them.”

It is not the first Doosan machine in the expanding Geo Quarries fleet. Along with the DX800 came a new Doosan 45-tonne articulate dump truck to join a 550 and a 580-loading shovel. “Our experience of the Doosan brand has only ever been a good one, as has the excellent back up service from Pioneer Plant with whom we have been dealing for the past couple of years. They’ve never let us down.”