New life for Canadian mine - Atlas Copco

The raise boring machine to the right of this picturelooks exactly like an Atlas Copco Robbins 73R, butthat’s where the similarity ends. This machine hasextraordinary torque which will soon be put to thetest at the Sedrina limestone mine in Italy.Getting ready for the Sedrina project: Edilmac’s raiseboringteam with the upgraded Atlas Copco raiseborer. From left,Marcello Fornoni, Giancarlo Dossena, Andrea Pellegrinon(Raisebore Operators), Sergio Moioli (Raisebore Foreman),Manuel Carli (Raisebore Engineer) and Adriano Facchinetti(Raisebore Divisional Manager).The Robbins that raises the barThe latest generation of Atlas CopcoRobbins raiseborer is helping Italianspecialist contractor Edilmac totackle demanding raise, pass and shaft taskswith increased confidence.Atlas Copco and Edilmac technical staffgot together with component suppliers tocreate an upgrade package for the company’sexisting 73R to give it more control,power and torque to tackle tough conditionspreviously only possible with largermachines.The upgrade involved close cooperationwith the manufacturer of the new compact,water-cooled, electric motor in Austria.Johnny Lyly, Atlas Copco Product Managerfor raiseborers, reports: “We carried outtests with the powerpack and motor overtwo days including stalling, backspin andfluctuating load to simulate all the conditionsthat might occur with a raiseborer. Theresults were very good, meaning we couldgo ahead with the retrofit work.”Meanwhile, Edilmac was fitting a newgearbox, supplied by Atlas Copco, to suitthe new variable frequency electric motordrive. “One result was a big increase intorque to 250kNm,” says Lyly. “The rigcould then be designated as an Atlas CopcoRobbins 73RVF C.”The new 73RVF C raisebore packagealso includes a new hydraulic powerpack,electrical transformer and switchgear unit,a special cooling unit that caters for allrequirements and a compact operator controlpanel.After the first raise reaming task – a ventilationshaft for an irrigation aqueduct inVal Fabbrica, near Perugia in central Italy– Adriano Facchinetti, Edilmac’s RaiseboreDivisional Manager, commented: “Withthe high power of 450 kVA instead of350kVA we are very happy with the newrig. The new 280 kW VF motor gives amaximum torque of 250kNm instead of theprevious 180kNM and the new console isa big improvement. The operators like it alot.”The Robbins 73RVF C is now workingon its second assignment, a slot raise forUnicalce’ s Sedrina limestone mine.12 Mining & Construction – 3 / 2011