Eurenco and Sme | Date: 2010-09-28
The present invention relates to suspensions of hexanitrohexaazaisowurtzitane crystals in a liquid phase (said liquid phase is composed, to at least 85% by weight, of a nonsolvent for hexanitrohexaazaisowurtzitane, said nonsolvent consisting of at least one nonflammable hydrofluoroether, and includes from 0 to less than 15% by weight of an organic solvent for hexanitrohexaazaisowurtzitane, more volatile than said nonsolvent, chosen from the group consisting of esters, nitriles, ketones and their mixtures), the production of said suspensions and their use to manufacture pyrotechnic objects. The use of said at least one hydrofluoroether as nonsolvent is particularly appropriate.
Brandt D.,SME |
Martinez I.,Mining Engineer |
French T.,Mining Engineer |
Slattery L.,Mining Engineer |
Mining Engineering | Year: 2011
In conclusion, it can be seen that consistent blasting practices have resulted in better control and consistency in fragmentation. This is evident from the crusher performance, crusher screen data and from the camera image analysis data. The costs associated with the improvements have not increased overall costs. Costs for increased drilling have been offset by using less explosive products or products of lesser strength. Costs have also been reduced by the increase in hauling efficiency, crusher throughput and less crusher wear. This report is not meant to focus on the actual values and ranges obtained through the implementation of the various technologies and systems discussed, as they will vary from site to site.This report is intended to provide a view of the process used to control and track throughput of material through the mining and crushing circuits. The process being used at Dos Pobres has proven to be repeatable and accurate on a day-to-day basis. It has shown what can be accomplished with interdepartmental cooperation and teamwork striving towards a common goal. It has also shown that for this process to remain successful there must be a team with a champion to keep the process alive.
Mining Engineering | Year: 2016
The work to create this access/recovery shaft was a monumental effort requiring precise coordination from the best in all disciplines and utilization of the most state-of-the-art foundation drilling equipment. There were many obstacles to overcome, as is the case in most emergency jobs, which required problem-solving "on the fly" to accomplish this monumental task within the extremely limited time available. A broad range of geotechnical construction techniques were required for the construction of the TBM recovery shaft on the SR 99 tunnel. Difficult ground conditions along with a condensed work schedule contributed to the complexity of the work. Moreover, a highly "dynamic" underground environment created by TBM operation and maintenance, site preparation work and maintenance, and dewatering, added unforeseen challenges. State-of-the-art specialty foundation equipment was mobilized, which worked concurrently with Leffer casing rotators and oscillators, and Liebherr duty cycle dig cranes. Other applications included various jet grouting and dewatering scopes completed both at grade and from within the shaft excavation. This work tested the capabilities of existing equipment, pushing them to (and beyond) their previous benchmarks, and in doing so has defined new limits for secant shaft construction. At the current time, repairs to "Bertha" are complete, she has been reassembled within the recovery shaft, and has advanced a few feet, to allow for evaluation of her recent repairs and ensure no further repairs are required. The present schedule calls for her to re-commence mining operations within the coming days and potentially complete the 2.4 km drive by January 2017. n John.
Sears A.E.,SME |
Mining Engineering | Year: 2014
The intent of geomorphic landform design is to mimic the function of the natural landscape. In a surface mine reclamation application, geomorphic landform design has the potential to mitigate stream loss. This research quantified features of reference landforms and performed computer modeling of a conceptual valley-fill design using geomorphic landform principles. A design was created using published design parameters with a software design tool (Carlson Natural Regrade with GeoFluv). Three additional designs, incorporating field-obtained regional geomorphic landform parameters, were completed and resulted in a geomorphic landform design specific to southern West Virginia. This work illustrates the importance of field determination of the ridge to head-of-channel input and drainage density parameters. Values of ridge to head-of-channel distance measured in this study were consistently an order of magnitude greater than software recommended values (SRV); SRV = 24 m (80 ft) versus field = 220 m (720 ft). Similarly, for the drainage density parameter, the software recommended range is 6 to 9 km-1 (80-120 ft/ac). The field measurements for central Appalachia quantified the drainage density to range from 5 to 5.3 km-1 (67-70 ft/ac). This affects Appalachian valley-fill stream construction by making the stream lengths shorter and the land slopes steeper with straighter headwater channels compared with areas in the southwestern United States. While the application of geomorphic landform design to surface mine sites presents challenges, this work provides support for future applications.
Manufacturing Engineering | Year: 2015
The article examines the importance of a healthy workforce in an organization. Model companies are outperforming others in large part because they manage and train differently. It is important to consider the dramatic existing and pending talent shortages. The skills gap is a major challenge for many manufacturers, due to limited employee pipeline, a retiring workforce, reshoring and the changing pace of technology. A structured training program using best practices based around competency models like Tooling U-SME's Competency Framework, blended learning which combines theory and application, and a data-driven approach to measuring, tracking and assessing learning can fill existing gaps and prepare the workforce for the future while meeting business objectives.
Joy G.J.,SME |
Colinet J.F.,SME |
Landne D.D.,Institute for Occupational Safety and Halth
Mining Engineering | Year: 2012
Although rates of pneumoconiosis in coal miners have declined substantially in the United States since the passage of the Federal Coal Mine Health and Safety Act of 1969, new cases continue to occur, including cases of rapidly progressive disease. In contrast, Australia's underground coal mining industry has reported few new cases of pneumoconiosis for more than 20 years. Mortality from coal workers' pneumoconiosis in official health statistics and the prevalence of pneumoconiosis among miners screened in X-ray surveillance programs are also lower in Australia. The U.S. National Institute for Occupational Safety and Health (NIOSH) was requested by both industry and labor stakeholders to examine this issue, with the ultimate aim of reducing the rate of pneumoconiosis among U.S. coal miners. A number of factors, including coal dust exposure, silica exposure and coal rank were examined as potential contributors to the above noted differences. Comparison of coal rank data from each country did not illuminate the issue. Air sample data from the coal mining industries in both countries show that coal dust levels in Australian mines are somewhat higher than those reported in similar U.S. mines; however, quartz exposure for Australian miners is lower than for many U.S. miners. If quartz is contributing to the greater number of cases of pneumoconiosis in the United States, more effective dust control measures, as well as an independent exposure standard for respirable quartz in coal mining, should be implemented to reduce this potentially disabling condition.
Sme | Date: 2010-03-26
The invention relates to a pyrotechnic gas generator (10) for a car airbag (12), the generator including a pyrotechnic charge and a pyrotechnic initiator (28) situated in a combustion chamber (14) and suitable for being actuated by a first detection system (30) for detecting an imminent collision state and/or by a second detection system (32) for detecting an actual collision state. The pyrotechnic gas generator of the invention further includes a gas flow passage (16, 18) between said combustion chamber (14) and said airbag (12), and at least one valve (34) suitable for being moved from a first position in which it defines a first flow section to a second position in which it defines a second flow section greater than said first flow section, or vice versa. In particular, the valve (34) is arranged in such a manner as to define a greater flow section when the pyrotechnic initiator (28) is actuated by the first detection system (30).
Sme | Date: 2010-06-29
Sme | Date: 2010-09-10
The subject of the present invention is a pyrotechnic gas-generating product, the composition of which comprises: guanidine nitrate, basic copper nitrate, and potassium perchlorate. Characteristically, said potassium perchlorate represents between 8% and 20% of the total weight of said pyrotechnic product and said composition additionally contains at least one oxide, chosen from metal oxides, metalloid oxides and mixtures thereof; said at least one oxide having a melting point below the combustion temperature of said pyrotechnic product and said at least one oxide representing between 1% and 5% of the total weight of said pyrotechnic product. Said at least one oxide improves the combustion, at low pressure, of said pyrotechnic product.
News Article | December 7, 2016
FORT WORTH, Texas, Dec. 7, 2016 /PRNewswire-USNewswire/ -- SME's AeroDef Manufacturing event will bring together the leading companies and executives from aerospace and defense manufacturing to explore current technologies and coming trends March 6 to 9 at the Fort Worth Convention...