Rokbak haulers join fleet at award-winning quarry

Smith & Sons (Bletchington), a UK-based producer and supplier of primary and recycled aggregates, purchased a pair of Rokbak RA30s – which started production in 2021 – from Molson Equipment on a 6,000-hour fixed-price service contract.

According to Rokbak, part of Sweden-based Volvo Group, the machines and their operators have been active at Gill Mill since arriving late last year.

“Operations at Gill Mill start at 6:30am with a standard maintenance check on equipment, and run until 5pm, five days a week,” stated Rokbak. “Once completed, operations commence, and the trucks bring up premium ballast to be converted into building materials.”

On that schedule, the RA30s are slated to work approximately 120 weeks at the site, based on the service contract.

Jeff Murphy, manager at Gill Mill, said early reports from the team and operators regarding the units has been positive. “The Rokbaks that we’ve got are integral to our operation insofar as their suitability to the site – they’re not too small and they’re not too big,” said Murphy. “With the constraints that we’ve got on some of the roads, they suit our needs, and we find them efficient and easy to operate.”

A specific regional nuance – the prevalence of Oxford blue clay – is also made easier to navigate, Murphy said. “Beneath our depot is Oxford blue clay, which is often utilised for restoration purposes but difficult to traverse,” he noted. “However, the Rokbak trucks have been fantastic with that great torque when moving through clay.”

Oxford clay is a Jurassic-era marine sedimentary rock formation which underlies much of southeast England.

RA30 specs and features

RA30 articulated haulers have a 28 tonne (30.9 US ton) maximum payload and a 17.5m3 (22.9yd3) heaped capacity.

At the Gill Mill site, they are used primarily for work on load-and-carry operations, dumping material into a hopper and feeding it to a main plant through a conveyer system. The distance travelled by each RA30 is approximately one mile per load, with each truck making between 25 and 30 roundtrips per day.

A Rokbak RA30 hauler at Gill Mill Quarry in Oxfordshire, UK. Two Rokbak machines have been working the site since October 2023 (Photo credit: Rokbak)

The RA30 has a maximum torque of 1880 Nm at 1400 rpm, designed to operate across difficult ground and improve traction in wet conditions.

One Gill Mill operator noted the RA30s’ rearview camera is vital.

“If we didn’t have it, it would make things harder for us,” said operator Warren Mobey. “Relying on just mirrors is not a way we could probably operate.”

The RA30s run on a Scania DC9 engine; a five cylinder, in-line, four-cycle, direct injection diesel unit. It is water cooled and turbo charged with air-to-air charge cooling, electronic engine management and engine exhaust brakes. Smith & Sons reported a 7% savings on fuel consumption costs – compared to previous machines – since the Rokbaks joined operations.

Gill Mill Quarry won British Aggregates Association (BAA) Quarry of the Year in 2020. It opened in 1989 and has planned reserves until 2035.