Drilling & Blasting
- Published: Saturday, 01 March 2008 07:00
Rock drilling and blasting tasks continue to receive enhancements in terms of both productivity and precision, as evidenced by the recent unveiling of
Rock drilling and blasting tasks continue to receive enhancements in terms of both productivity and precision, as evidenced by the recent unveiling of new equipment for quarry operations. Drilling rigs are providing operators with more intelligence than ever to keep them working efficiently while maintaining pinpoint control of their drills. One manufacturer is offering a drilling attachment that can convert an operation's excavators into precise drilling machines in minutes. Blast-initiation equipment also is becoming increasingly intelligent with advances, such as upgrades in wireless remote blasting, that give operators both powerful information to aid their quality-control efforts as well as time savings during setup.
Atlas Copco's COP 1640 rock drill is optimized for difficult drilling tasks in small to medium-sized surface applications. This model replaces the previous version COP 1838LE. The drill is equipped for efficient drilling of holes in the 2 to 31/2 inch (51- to 89-mm) range and features a large, robust driver and gearing to help extend the service life of wear parts and keep operating costs to a minimum.
Three different stroke settings are available that can be adjusted according to rock hardness to ensure an optimum penetration rate in various rock types. An exclusive dual-damping system provides reflex damping and a special extractor is available for drilling in particularly difficult rock.
Along with the family of robust rock drills that includes the COP 1240 and 1840, the COP 1640 has a straightforward design that is intended to make the unit easy and quick to service as well as keep spare-part costs down.
The company also has equipped its ROC series of surface drill rigs with new cabins designed to provide increased operator space, improved comfort and higher levels of safety. By relocating the instrument panel, the company has improved the operator's view. An angled front window, roof window and the design of the cabin's frame allow the operator to observe the entire drilling process. The forward-angled front window of the cabin also reduces the amount of dust that can accumulate on the surface. A number of glazing options are available, including clear or tinted laminated panes, as well as an extra 24-mm pane that provides extra protection.
Ergonomics also are emphasized, as free space around the operator has been significantly increased. Relocation of the door to the front of the cabin results in easier access to the cabin. The operator's seat is fully adjustable and ergonomic placement of joystick controls for drill- and rod handling operations are designed to minimize fatigue and maximize comfort. A touch-control panel for supporting functions also is included.
The cabins feature an improved ventilation system that includes a relocated air intake, two-stage filtering, and more effective heating and air conditioning. In addition to effective noise and vibration insulation, the new cabins exceed ROPS and FOPS requirements. An easy-to-change air filter located at ground level, and a service platform that allows access to the window for cleaning and changing wiper blades, which also doubles as a toolbox, are two new features designed to facilitate maintenance.
DP1500i rigs from Sandvik use the latest technology for rock excavation process optimization. The offspring of the Tamrock Pantera family, the rigs are equipped with practical intelligence and a user interface with multiple screen views that provide the operator with information on the drilled meters and holes, diesel and percussion hours, the amount of burned fuel and, most importantly, the condition of the drill. This allows the operator to make accurate preventive maintenance schedules to minimize downtime and optimize drill use. The operator also is informed about what service parts are needed when appropriate.
Several preset drilling parameters (for different rock conditions) and optional storage settings (for different sites) aid productivity. Automatic feed alignment, available as an option, also increases drilling efficiency. Optional one-hole automatic drilling-to-depth ensures consistent drilling.
The rigs are designed for speed and maneuverability. Yet an optimized center of gravity keeps the rig balance unchanged even when oscillation is unlocked. Ambient-controlled oil cooler fans for oversized coolers and a fuel cooler ensure that the rig keeps working in any temperature. Load-sensing compressor pressure control, active diesel RPM control and ambient oil-cooler-fan control help achieve low fuel consumption.
The joysticks are armrest-integrated to increase drilling comfort. The rigs also are equipped with high-frequency drifters and an easily adjustable drilling control system with all parameter settings in the cabin. Advanced air conditioning, a double roof, a cool white color, selective glass windows and optional roller shutters that stop glare maintain operator comfort. A large window surface with a high-resistance steel grill offers high visibility and safety.
Access has been prioritized for efficient service. A clear layout and gull-type service doors provide easy reach to components. Also, daily and weekly service points are accessible from ground level and all oil removals are centralized. Practical, step-by-step troubleshooting instructions and a self-diagnostics system facilitate quick fault-finding.
ExcaDrill offers drilling attachments for the AutoDrill automatic drilling system that are accessories to the excavator and allow the aggregate producer to use the machine's existing hydraulic system. Changing to a drilling unit attachment is said to take less than five minutes. In addition, the wide working radius and maneuverability of the excavator give the operator high drilling productivity without the need for special training; one ExcaDrill attachment can be switched among multiple excavators.
Optional laser provides precise drilling depth of all holes. Four sizes covering hole diameters from 27 to 127 mm are available. Optional rod changer that allows drilling holes up to 29 meters deep also is available.
The AutoDrill system immediately reacts to changes in the rock and monitors drilling resistance; when the resistance grows, it automatically readjusts the drilling parameters. This feature is designed to make the holes straighter and reduce drill wear.
A control panel installed inside the excavator cabin features an integrated graphic monitor designed for convenient use. The control panel includes a device to monitor the drilling depth and angle, which can be changed during drilling. ExcaDrill units also can be equipped with a video camera mounted on the excavator's boom, providing the operator with a close-up view of the drilling operation.
Austin Powder Co. provides a comprehensive line of industrial explosives and accessories as well as blasting services to customers around the world. The company's high explosives consist of detonator-sensitive emulsions and high-density molecular explosive boosters. Its Emulex emulsion products are energy-efficient high explosives. High-density cast boosters come in various sizes and detonate at velocities in excess of 24,000 fps.
Austin Powder also offers electric and non-electric blast-initiation systems. RockStar, designed for safety and reliability, features a unique fusehead design and reportedly the industry's strongest aluminum shell. ShockStar millisecond delay detonators have a uniform base, ignition and delay charges that are designed to provide consistent breakage and fragmentation. The company's detonating cords are equipped with an explosive core of PETN protected by a textile casing, which is covered by a seamless plastic jacket and outer layer of high-strength textile yarn. The EmuLine multiple explosive cartridges are attached to a continuous length of detonating cord for presplitting.
In addition, Austin Powder provides blast assessment and instrumentation. Pre-Blast assessment technology and services include ABS (Austin Blasting Software), computer-aided blast design that allows computer simulations and blast design review during the planning stages; laboratory/field tests; general surveying; 2-D or 3-D Laser Profiler, which provides data to help control blasting safety and the environmental effects of blasting; QED virtual mining software, a computerized ìvirtual mining methodî software package; borehole trajectory/deviation; hole measurement; and geologist's compass.
Blast-assessment technology and services include high-speed cameras, data-acquisition systems, velocity of detonation measurement and timing and seismographs. Post-blast assessment technology and services include laser profiling and photographic fragmentation analysis.
Dyno Nobel's Digishot electronic initiation system is configured with no delay assignment on the bench as the blaster simply uses the Tagger to relay its location in the pattern to each detonator. The system simultaneously checks the functionality of the detonator, including current leakage or a short circuit. The Tagger also checks a connected row or the entire blast, ensuring that all detonators have been connected to the busline. The Tagger automatically detects a forgotten tagged detonator connection down to the row and location within that row, saving time.
The system has been conceived to provide more control of vibration, crusher throughput, highwall stability and operational efficiencies. Menu-driven software has been developed to minimize end-user training time and the hook-up process is quick because delay timing can be entered ahead of time. In addition, delay timing can be completed with auto-programming to save time and reduce errors or the manual programmable mode can be used to accommodate virtually any delay scheme. Easy-to-follow screen menus lead the blaster through all delay and firing operations for up to 15 detonators per blasthole.
The company also offers Smartshot, a four-wire programmable system with wireless remote and complete timing flexibility. Wireless remote firing allows operation from up to 6,000 line-of-sight feet from the bench. A line-in wire also can be used with the system where required. Multiple programming options are available for specific applications. From one initiation point in the row, users can individually program every blasthole, auto-program rows of detonators or use a combination of the two. The detonator can be programmed upon deployment or after the whole blast is connected. Intuitive software eliminates the need to program each detonator individually. The system allows the user to achieve blast objectives such as vibration reduction and fragmentation improvement.
The Uni tronic system from Orica consists of programmable electronic detonators and hardware to identify, test, program and fire the detonators. It includes a scanner, network tester and blast box. Uni tronic detonators fit into all conventional boosters and each has a unique identity code written into its memory. This identity code is represented in the form of a barcode printed on a flag-tag attached to the wire near the connector. A handheld laser scanner is used to read this barcode and a firing time is assigned to this detonator identity code in the scanner memory, using either an auto adding increment or the numerical keypad on the scanner.
After the blast has been charged and stemmed, each detonator is connected to the surface harness wire by an insulation-displacement connector. Once all detonators are connected, the resulting wiring network can be tested for full integrity with the handheld Network Tester to ensure a clear path of communication to each detonator. Once the blast area is cleared and secured, the blast box is connected to the detonator network via a firing cable. All detonator identity codes and assigned times that are stored in the scanner's memory are downloaded to the blast box via an infrared port. Each detonator is then powered up and programmed with its firing time according to its identity code. The blast box reports back the details of any detonators that are not communicating properly with it. Once all detonators have been programmed and all detonators have confirmed their presence, the blast can be fired.
The new Minimate Pro series of vibration monitors from Instantel consists of smart devices that can be programmed for new features as they are released by Instantel through Blastware, the software companion provided with the monitor. The Minimate Pro4 model is equipped with four recording channels and can be set up with one Series 4 Geophone (ISEE or DIN) and an ISEE Linear Microphone. Another model, the Minimate Pro6, has six recording channels with a choice of two Geophones (ISEE or DIN) or a Geophone and an ISEE Microphone.
INFORMATION PROVIDED BY EQUIPMENT WATCH.