Sydney, August 11, 2014 – A twin-head Rokla D30 rockwheel is being used for high tolerance rock removal in a station box being excavated during construction of Sydney’s new north-west rail link.
The work by contractor JK Williams involves excavation and removal of 80,000 cubic tonnes of shale material, which is being recycled by one of Sydney’s brickworks.
A rock hammer attachment is used to remove coarse material, followed by trimming with the rockwheel to efficiently produce a smooth face to the trench wall that is required to be held within a 40 mm tolerance. JK Williams’ site supervisor, Mitch Long said the Rokla wheel was acquired several weeks ago as a result of a decision to optimise this construction phase.
“We use the Rokla rockwheel because of its efficiency in controlled removal of rock from the trench wall. The rockwheel gives us the accuracy we need to hold the specified tolerance, and so far we have achieved excellent results”’ Long said.
“As with any major infrastructure project, timing is of critical importance. In this case there can be no delay in having the site ready for access by a new tunnel boring machine with daily operational costs around $175,000.
“Downtime on the rockwheel has been surprisingly minimal: we have only needed to replace two teeth on the twin-head D30 rockwheel attachment which has overcome the challenge of working around many columns’, he said.
Rokla rockwheel attachments are available from Semco’s sales and service centres in Sydney, Melbourne, Brisbane, Newcastle, Queanbeyan and Goulburn, as well as Semco’s national dealer network
Article Courtsey of Semco