Liebherr: The King of Rock

Liebherr emerged as first choice for an expanding quarry business as it searched for a single flagship excavator to replace a pair of ageing machines at a newly acquired hard rock operation...

Tynedale Roadstone is the quarrying and asphalt production arm of Durham-based MGL Group and operates across the north-east of England and North Yorkshire. Its recent acquisition of the stock and assets of Kinegar Quarries saw it move across the border into Scotland with the addition of two more sites, Fulfordlees and Glenfin in Cockburnspath near Dunbar.

Fulfordlees is a large sand and gravel operation while just a few miles away is Glenfin, a hard rock quarry producing a range of aggregates from high-quality, high-PSV greywacke sandstone. In the wake of the takeover, both sites have undergone significant upgrading to include better welfare facilities, modernised production and improved dust suppression. One of the biggest single investments was replacing Glenfin’s frontline excavators to boost productivity and reduce operating costs.

The site has never been blasted, with all material won by ripping and loading, most recently by 36- and 46-tonne excavators which, while still in operation, had passed their prime in terms of performance and reliability.

Quarry Production Manager John Laing explained: ‘We decided to streamline operations by adopting the same method but using only a single machine. We compared several brands before choosing the Liebherr R 966 and since its arrival it has demonstrated exceptional performance, easily ripping and loading the hard material.’

The new flagship machine sits on a pair of 5.69m long track frames with 600mm wide double grouser pads to give the required stability for the tough application. Track frames are fixed, although Liebherr does offer a variable gauge option to reduce transport width. As with other large excavators in the manufacturer’s G6 range, the R 966 has a rounded and streamlined upper structure housing a fuel-efficient 16-litre V8 Liebherr diesel engine delivering 435hp.

Various boom and dipper options are offered on the R 966 to suit a variety of applications. Tynedale’s new arrival is working exclusively on hard rock excavation so a 7m boom and 2.6m stick were deemed to be the perfect combination. Also in the specification was a hitch, bucket and ripper combination from Miller Groundbreaking to enable the excavator to operate at full potential.

‘The R 966 has demonstrated exceptional performance’ John Laing, Quarry Production Manager

The R 966 has a maximum bucket capacity of 5m³ although the customer chose a smaller 4m³ version with a width of 1900mm to match the 30t-capacity dumper currently on site. The heavy-duty bucket weighs almost 4.5 tonnes, the hitch adds a further 3.5 tonnes and that translates to an average of 14 tonnes on each pass.

‘The narrower bucket is a good match for the truck and allows us to penetrate the material easily,’ said operator Lea Laughlin. ‘Even with a full bucket, the Liebherr is very stable and that helps when ripping as the extra weight allows me to put more force through the tip without the risk of the machine being pulled around.

‘This new machine is much bigger and far more powerful than others we’ve had before and I’m excited to use all its features,’ she added. ‘The cab is much more comfortable than previous machines, and the power we have now, especially when it comes to ripping the material, has impressed me so far.’

John Laing added: ‘By using one larger excavator instead of two smaller ones, we’ve streamlined operations and reduced costs. That has increased production, allowing us to reduce operating hours while keeping up with demand.’

MGL Group operates across diverse construction specialities to reshape the built environment. These include civil engineering, demolition, earthworks, road surfacing, asphalt production, quarrying, aggregates and recycling.