Silence In The Suburbs
Atlas Copco to launch silenced drill rig for noise-sensitive sites
Atlas Copco are set to launch the world’s first ROC-series surface drill rig with a substantially reduced noise level, making it the quietest-running rig of its kind. The silenced ROC D7C has a noise level approximately 10db(A) below that of other equivalent rigs on the market, making it particularly suitable for use in small and medium-sized quarries close to residential or urban areas.
Anders Hedqvist, R&D manager at Atlas Copco Surface Drilling Equipment, explained: ‘Atlas Copco have a clear strategy when it comes to environmental and safety issues. We are in the forefront of development and the silenced ROC rig plays an important role in this work. In future, people who live near a quarry or construction site will have quieter surroundings.’
In many countries strict noise restrictions are imposed on drilling operations in close proximity to urban areas. Atlas Copco say this presents new opportunities for companies using their silenced ROC D7C rig, which has an advanced silencing system comprising many components — including a hood that covers the entire drill mast — to reduce the overall level of noise generated by vibration in the drill steel, feed system, boom and body of the rig.
The noise carpet diagram shown below demonstrates the relative difference in sound level generated by a rig equipped with the new silencing kit, compared with a standard rig without the system.
In addition, the ROC D7C’s advanced and more efficient hydraulic system, together with a new, more powerful Cat engine, makes it possible to lower the idling rev/min and to choose the optimal power needed for drilling in different rock conditions. This in turn makes it possible to reduce fuel consumption by up to 30% compared to similar rigs on the market.
The rig itself is operated by an upgraded digital rig control system (RCS), which permits increased shift capacity through faster positioning. According to product manager Lennart Lundin, half the time on each shift is used for actual drilling and half for tramming, positioning, rod adding and preparation for drilling. ‘By using the new ROC D7C, with its automatic rod-adding and auto-feed-alignment system, productivity can be increased by 10% or more,’ he said.
The silenced ROC D7C rig is just one of a new, upgraded family of ROC D5/D7 rigs from Atlas Copco, designed to meet the new Tier 3/Stage 3 exhaust emission limits and featuring stronger and stiffer booms for better collaring and more stable drilling. Equipped with 117kW (157hp) engines, the ROC D5 models are suitable for drilling holes in the 35–89mm range, while the 159kW (213hp) ROC D7 models are suitable for holes in the 64–102mm range.
Atlas Copco have also announced the introduction of satellite-based GPS facilities on their computerized ROC D7C and ROC F9C models, in response to customer requests for greater productivity and accuracy. With GPS-equipped rigs, all set-up operations are carried out from within the cab using a single display panel, with the driller being guided through a short series of user interface displays giving instructions on correct hole location and alignment.
Accurate collaring followed by drilling to controlled depths is then performed to pre-planned drill patterns, without the need for the traditional time-consuming set-ups. All drilling functions are monitored and controlled to provide a record of hole alignment, burden and spacing.
According to Mr Lundin, the use of GPS will greatly reduce set-up time, especially when working at night or in foggy weather conditions. It will also provide automatic compliance with pre-planned drill patterns and better blasting results, especially when coupled with hole logging, as well as allowing all drill and blast data to be recorded in one place for easy analysis with ROC Manager software.
Atlas Copco Construction & Mining Ltd, Swallowdale Lane, Hemel Hempstead, Herts HP2 7HA; tel: (01442) 222100; fax: (01442) 234467; email: [email protected]
