Page 44 - HUB-4 Magazine Issue 88

Quarrying News
Moving Walton’s Mountain
A father and son team producing some of the finest architectural stone in the world relies on Liebherr equipment for extraction and processing duties.
Gwrhyd Specialist Stone is found high up in the Swansea Valley overlooking the Black Mountains of Wales and it’s here that Michael Walton and son Charles have spent the last decade assembling a fleet of specialist equipment to help develop the site to its full potential.
Together they are responsible for the day-to-day running of a quarry employing 22 people to produce just 5,000 tonnes a year; quarries of similar size could output up to 500,000 tonnes a year but volume at Gwrhyd is small because of the specialist nature of its stone.
Liebherr has been an important supplier of equipment since the beginning. The operation still uses its original L 510 Stereo wheel loader and over the years it was joined by an L 509 Tele wheel loader and an R 926 G8 excavator, the latter now replaced by a slightly larger R 930 G8. ‘The R 926 did exactly what we wanted it to do and served us well over the past few years,’ noted Charles.
Working alongside another manufacturer’s used 14t excavator, used for loading the site’s two-deck screen, the new R 930 has been a hit with regular operator Jamie Evans who came off the 45-tonner originally used at the site. ‘It was an ideal machine at the top of the quarry but as space got a little tighter, it proved to be too big,’ he recalled. ‘The R 926 was also great and a massive step up in comfort over the older model and it’s now the same for the R 930. It’s a really comfortable machine, still has bags of power but hardly uses fuel. We don’t do a great deal of fine work here – we’re usually flat-out moving the stone – but we’re still averaging just over 16 litres per hour.’
Boom and stick options for the R 930 G8 model include standard mono boom, a straight demolition boom and a variable arm version, with Gwrhyd specifying the standard configuration which combines a 6.2m boom and 3.2m stick, topped off with a Miller Groundbreaking coupler for fast changes between buckets and a breaker. Regular use of the breaker means the excavator has a dedicated drain line back to the hydraulic oil tank to ensure the oil is returned to lower its temperature as quickly as possible.
The R 930 G8 tips the scales at just under 31 tonnes in its LC undercarriage version and has a Liebherr 7-litre, D 934 engine developing 245hp at 1800rpm. The engine is designed to deliver peak torque at low engine rpm, the R 930 achieving 1255Nm at just 1350rpm. That lowers internal and external noise levels and reduces fuel consumption significantly.
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www.hub-4.com Sept/Oct - Issue 88