Performance Enhancement of DIAdrill Operations
Conventional drilling of rock, in most mining applications, uses the mechanical impact of a metal tool to create the advancing hole. This technique, which has gradually increased in power and thus penetration rate has, however, certain inherent disadvantages. These range from the overall weight of the equipment which must be located at the free face of the hole to the maintenance of alignment over long distances, particularly with smaller diameter holes, where the limitations of thrust delivery through the small diameter rod can limit performance.
Influencing factors for abrasive flow rate and abrasive flow quality of abrasive injection waterjet systems for tunnel excavation
: A new rock excavation method using an abrasive waterjet system is under development for efficiently creating tunnels and underground spaces in urban areas. In addition, an appropriate abrasive flow rate and abrasive flow quality are important for the new rock excavation (cutting) method using an abrasive waterjet system. This study evaluated the factors influencing the abrasive flow rate and abrasive flow quality, specifically the abrasive pipe height, length, tortuosity and inner diameter, through experimental tests. Based on the experimental test results, this study suggested optimal conditions for the abrasive flow rate and abrasive flow quality. The experimental results can be effectively utilized as baseline data for rock excavation methods using an abrasive waterjet system in various construction locations such as tunnels near urban surroundings, utility tunnels, and shafts.
International EMS systems: New South Wales, Australia.
Australia has an area of 7,692,024 km 2 and a population of 19,169,083. The state of New South Wales (NSW) has an area of 801,428 square kilometres and a population of 6,663,700 (June 2002). It contributes 10% of the land area of Australia and 34% of the population. The length of the coastline is 2007 km with an east-west distance of 1450 km (Fig. 1). Approximately 90% of the NSW population resides within 100 km of the coast. The population density is greatest in the Greater Metropolitan Region around Sydney, an area of 1580 square km, population of 4,154,722. Only 0.6% live in regions classified as remote or very remote (based upon distance to regional townships). The climate is generally mild, although temperature extremes range from � /20 8C (Charlotte’s Pass) to 50 8C (far Western NSW). The highest point is 2228 m at Mt. Kosciuszko. However, most of NSW is below 500 m in altitude.