UNITED KINGDOM: Volvo machines have played a role in ensuring the future of the renowned Portland stone
by Tony Lawrence
London and the Isle of Portland do not, on the face of it, have much in common. London boasts a population of more than eight million, while Portland, jutting out of England’s south coast, is home to an estimated 13,000 people. London covers 1,583 square kilometers (611 square miles). Portland measures 6km long and 2.7km wide (4 x 1.7 miles). London attracts around 15 million visitors annually. Portland does not!
Yet how many of those London tourists realize, as they admire such landmarks as Buckingham Palace, St Paul’s Cathedral, the British Museum or St Martin-in-the-Fields, that those buildings are built with the striking white stone hewn from the country’s Jurassic coast?
Portland, indeed, has provided London with much of its iconic heart. Stone has been quarried on Portland – a near-island close to the town of Weymouth and attached to the mainland by a single road – since Roman times. Renowned for its durability and beauty, the stone was being shipped to the capital as early as the 14th century and has been the subject of intensive opencast quarrying for 300 years.
Things, though, have changed. The Roman slaves and their pickaxes have gone. So have the loud detonations and clouds of dust that emanated from the quarries just a few years ago.
ADAPT OR DIE
Today, emphasis is on the Volvo attributes of quality, safety and environmental care. Quarrying is out of favor. Now the best way to produce Portland stone, it seems, is to go underground and cut it out with computer-controlled mining equipment, diamond-tipped cutting machines – and a bespoke Volvo wheel loader or two.
As Mark Godden, mine manager with Albion Stone PLC, explains: “In recent years, obtaining planning permissions for new green-field quarries has become virtually impossible due to the unavoidable environmental impact associated with opencast quarrying. Disused quarries already litter the Isle of Portland – they’re now home for rare flora and fauna.”
Albion Stone, founded in 1927, knew it had to change with the times. “We had to adopt a radically new approach to survive,” says Godden. “It was a case of adapt or die. So in 2002 we started investigating whether we could mine rather than quarry the stone.”
Godden and his colleagues visited similar sites in Europe before Albion Stone, which employs around 70 people in its mines and masonry factory, opened a trial mine to see
if the plan was feasible. It was. In 2008, the Jordans mine was opened and has since been extended. Within a few years, Albion Stone had switched its entire operation to high-tech mining, with two functioning sites and a third under development.
The final chapter of the success story came two years ago when a brand new, bespoke 25-tonne Volvo L150H wheel loader made its appearance, to be followed by a
second last year.
“Basically, we cut horizontal tunnels in the face of our old quarries to open the mine, and then create ‘rooms’, with supporting pillars and rock bolts in the roof. The rock faces are cut and then ’hydro bags’ are inserted and inflated with water to help shear off the stone,” explains Godden.
“This is where our Volvos come in. Fitted with specially adapted 1500mm block forks, they prise out the blocks, weighing up to 14 tonnes, which are then transported to our factory to be cut into shape and worked on by our masons to make cladding, walling, flooring and paving products.”
Initially, Albion Stone had relied on a conventional forklift, then tele-handlers to carry out the work. “They weren’t robust enough, though. We needed a really powerful, productive and well-built machine,” Godden says. “But there was a catch – it also had to fit into the mine.”
Godden turned to Volvo CE. He liked the power of the L150G wheel loader – but it was too big. “So I did some research and found a specialist Swedish company which said it could lower the exhaust stack and reduce the cab height by around 350mm. Volvo helped us with the modifications and we haven’t looked back.”
Volvo CE Area Business Manager Neil Cooper recalls: “It was a brilliant project to be involved in. Mark is very knowledgeable. Our technical teams visited Portland to check on all the measurements and lifting calculations and then we approached the subcontractors, who have since become one of our preferred suppliers, to make the changes and re-certify the structure of the cab.”
The first adapted Volvo machine quickly proved its superior power and traction but, more importantly, offered significant breakout torque thanks to its patented torque parallel (TP) linkage. “That led to us getting a second one, followed by a couple of five-and-a-half tonne Volvo excavators. They are fantastic things, do the job very well and the build quality is immaculate,” says Godden. “The first wheel loader felt like a bit of a gamble but immediately it got to work we knew it was the right choice.”
Having prised the stone blocks clear, the L150Hs carry them out of the mine to be sorted and sawn. They then load the material on to trailers heading for the cutting shops. When time allows, the two wheel loaders also clean up rock debris, using a 3.8m³ bucket.
“They’re like Swiss Army knives,” says Godden.
To ensure such versatility, they are fitted with Volvo CE’s optional boom suspension system, as well as a hydraulic quick hitch to speed up attachment changes. Extra safety features for working underground include a fire-suppression system, double-pole battery isolator and a Chalwyn valve to meet mine regulations on exhaust emissions.
The machines, backed up with Volvo CE’s Silver customer support agreements, also sport counterweights to help them deal with the heaviest of loads, as well as additional LED working lights.
“I’m very pleased that we decided to go for these machines,” adds operator Wayne Flew. “I’ve been in the business for quite a few years and I reckon these machines are the best you can get for doing this job.”
Albion Stone’s new way of working has been met with universal approval by the local population – and especially by the members of the cricket club whose pitch lies directly above the Jordans mine. “The pitch is 16 meters above the roof of the mine,” laughs Godden. “Visiting teams don’t have a clue that we are working away below them while
The company’s staff are rightly proud of their work. Last year, they were taken on a trip to London to mingle with the tourists and see some of their ‘finished articles’ on public display. London and the Isle of Portland, it turns out, have rather a lot in common after all.