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By William P. Harris

The Lincoln Terminal System is described as a device with the capability to deliver technical information, monitor student performance, and assure learning in industrial training. An experimental unit, the LTS-3S, was constructed and delivered to the Bureau of Mines with appropriate lesson material for a test of feasibility and acceptability of this form of training in the mining environment. Operations were conducted at two mine maintenance schools. The overall results were that (1) there was a substantial improvement between tests before and after self-training on the LTS, (2) students found this an acceptable way to learn, and (3) reaction by training personnel and supervisors was favorable toward the feasibility and advantages of using the LTS in the mining environment. Transfer of the LTS to industry depends on availability of reliable units and adequate lesson material. The requirements for authors of training materials were established based on advice from mine training experts, formal analysis of lesson development procedures, and experience from efforts in lesson development at Lincoln Laboratory-It was concluded that experienced mine training instructors were best qualified to proceed effectively and economically to format instructional material for the LTS, if supported by well-designed facilities and services. Discussion with mining experts confirmed the desirability of generating training materials and delivering instruction at distributed locations to meet local training needs and in direct support of industrial operations.

Jan 1, 1975

By Seppo] [Kreula

Outokumpu Oy has acquired considerable experience with on-stream X-ray fluorescence analyzers and with computer control of flotation processes over several years. It became evident at the outset of this work that a reliable and accurate on-stream analyzer was more than a collection of different pieces of hardware linked together. Extensive work was done to develop an integral analyzer system, beginning with process samples through the spectrometer to report typewriters, recorders and the control computer. To date, over ten Courier-300 analyzer systems based on this development have been installed world-wide, several of which provide the key information for successful computer control systems. Computer control of flotation processes has been under development at the Pyhäsalmi concentrator since 1968. Two different control strategies have been implemented. The copper flotation is controlled by means of a mathematical model and economic criteria, whereas the "evolutionary operation principle" is applied to the zinc flotation. The computer control system installed at' the Vuonos-mine has been developed according to the same guidelines. In order to consolidate this wide experience, a flotation computer control system, Proscon-100, was developed by Outokumpu Oy, and the first system was installed at Kotalahti in 1972. In addition to the technological experience, enough information has also been gathered to illustrate the economical, benefits accruing through the use of these advanced tools of automation.

Jan 1, 1973

By Randy Clarkson

Sluiceboxes which are designed and operated as recommended from our recent research can provide much higher concentration ratios than most other gravity concentrators (up to 50,000: 1) at very high overall placer gold recoveries (95-99%). They are also very reliable, inexpensive and simple to operate. A sluice­box is a rectangular flume containing riffles on matting, through which a dilute slurry of water and gravel flows. However, sluiceboxes operating under ideal conditions are actually cen­trifugal concentrators whose riffles overturn ribbons of slurry to form vortices. At the bottom of these vortices, centrifugal and gravitational forces combine to drive gold particles into matting (figure 1).

Jan 1, 1996

By Henk van Muijen

To create a feasible plan to extract marine minerals there are a significant number of factors that must be analyzed. Most of these are known from conventional mining types. The following issues are the most relevant factors that have to be considered for mining a deep sea reserve economically: Sufficient reliable geological, physiographic data to create a proven reserve and mineral resources, Environmental Conditions, Geological & Geotechnical Study, Mining and ancillary equipment selection (design) and suitability, Environmental Conditions, Initial Transportation (seafloor to surface), Locations for stockpiling & processing, Processing, Power requirements, Land (Seafloor) ownership, Government, Economic Climate, Waste Handling, Methods of obtaining information and Post-Mining Activities.

Jan 1, 2008

By G. L. Mowrey

One critical element of the US Bureau of Mimes computer- assisted mining research program is the development of a reliable coal interface detection (CID) system. Several promising CID concepts currently being investigated by the Bureau include natural gamma radiation (NGR), vibration and passive infrared. To help establish which CID sensor technologies need to be developed for a given seam, coal and adjacent rock samples (immediate roof and floor) are being collected from selected major coal seams in the US and are being analyzed in terms of NGR and other geophysical measurements. This paper provides a brief overview of the Bureau's work in these CID areas.

Jan 1, 1992

(Under this heading will be published notes sent to the Secretary of the Institute by members or other persons introduced by members. ) Member, age 33, single, desires position as null superintendent or charge of mine and mill. Twelve years' milling, cyaniding and flotation in the southwest and Mexico. Will go anywhere. No. 458. Member, mining engineer and geologist, graduated, from- mining college, age 27, single, exempt, with practice in metal mining, surveying of any kind, field geology and ore testing, desires to .engage as geologist or mining engineer with a reputable concern in the west or east of. U. S. Hard worker and reliable. No: 459.

Jan 6, 1918

By H. J. Ilgner

Previous applications for using waste rock for backfilling in South African gold mines were reviewed and it was found that in many cases the mechanical equipment selected and the design philosophy applied did not meet the requirements. A more simplified system configuration is proposed, which allows the equipment to be relocated as mining progresses. Innovative high-intensity grinding and dense-phase pumping technology are proposed to provide a low-porosity backfill with a particle top size of 5 mm to 8 mm. According to recent rock mechanics modeling work, this comminuted waste backfill material can provide a good compromise between underground support characteristics and reliable hydraulic transportation behavior.

Jan 1, 2001

By Paul W. Patton, Christopher Scott Smith

The use of ceramic-in-rubber pulley lagging on bulk material belt conveyors is increasing. Many of the applications have been on pulleys originally installed with rubber lagging. There is a consensus that the fiction characteristics of the ceramic material are significantly better but the factors quoted vary, possibly because the more complex traction mechanism of the dimpled ceramic elements on the belt is not well understood. In this paper we will report and evaluate field data from a number of field installations to provide a study of actual friction characteristics in successful applications for those who desire reliable data for using ceramic-in-rubber lagging in new conveyor designs.

Jan 1, 2004

By Jerry R. McGaha, Joseph A. Dos Santos

The favorable economics of conveyor based haulage, especially in moving large volumes. has long been acknowledged. This has given impetus to significant developments over the last two decades in conveying systems and equipment. Such developments have resulted in improved equipment and system reliability, versatility and mobility. The present writing presents conveyor systems and their variations. Long overland conveyors of various profile and plan layout are considered along with various typical support systems. This includes discussion of horizontally curving, two-way and booster driven conveyors. High Angle Conveyors-[HACs] are reviewed, citing in-pit as well as plant application. Finally, several important advances in idler and in pulley design are presented.

Jan 1, 1989

By R. L. Blackwood

The solid inclusion cell for absolute in situ stress measurement has been found to give reliable results in coal. The cell is described briefly, along with the methods of installing, overcoring and taking readings in underground coal mines. The validity of the cell performance is demonstrated by reference to the stress-relief curves obtained during overcoring and a three-dimensional B.I.E.M. analysis of the installation to test for stress anomalies deriving from the geometry of the overcoring groove-borehole-cell arrangement. Case studies of two stress measurement projects using the cell are presented for coal mines in New South Wales, Australia.

Jan 1, 1982

By M. Guarascio

Microseismic monitoring of mining areas is a developing technique, described here for the Belvedere Spinello Mine, southern Italy, where dissolution cavities in the mining area have proved problematic. The preliminary condition for locating seismic impulses has been found to be a reliable seismic ground model. Ground signals are continuously recorded by means of data from piezometric wells, for sinkhole data, and linked gephones, for microseismic data. A computer system has been implemented to collect, analyse and interpret the incoming signals consequently, identification and classification of hypocentres of activity is facilitated, with advantages in terms of safety, preventing harmful side-effects, including rock bursts, and for environmental conservation.

Jan 1, 1987

By K. C. Foye

Use of load and resistance factor design (LRFD) of foundations is growing, from offshore applications to bridge applications and beyond. The development of load and resistance factors for design has traditionally relied on calibration to traditional factors of safety. This technique, however, offers little insight into the challenges of pile design. This paper discusses an approach to LRFD factor development that seeks to isolate the various sources of design uncertainty. Using this approach, reliability analysis is used to develop resistance factors for the design of driven pipe piles in sand. These findings shed light on many aspects of the ongoing discussion of how LRFD can be successfully applied to pile design.

Jan 1, 2008

By Tom Shumka

INTRODUCTION ?The Electro-Magnetic Crack Detection (EMCD) technique is an electromagnetic inspection method used for detecting and sizing surface breaking flaws. ?It works well on structural material or welds, ferrous or non-ferrous metals. ?EMCD?s rapid scanning is achieved using a hand-held probe. ?EMCD provides reliable crack detection and sizing (length and depth). Cracks can be sized accurately. ?EMCD dramatically reduces most cleaning requirements as there is no need to clean to bare metal. ?EMCD is capable of inspection through thin metallic coatings, or through non-conducting coatings up to 10mm thick. ?EMCD allows full data storage for back-up, off-line view and audit purposes.

Oct 1, 2010

By J. E. Chilton

Methanometers with catalytic heat- of-combustion sensors used in coal mines today will read low for flammable gases when oxygen (0,) concentrations are low or when methane (CH,) concentrations are greater than 10%. Thus, these methanometers may not be reliable during operations such as fire fighting or recovery of sealed mines. The U.S. Bureau of Mines developed a total flammable gas detector (TFGD) to measure CH, at concentrations up to 100% and to measure flammable gases in low 0, concentrations. This paper describes the operation and construction of the TFGD and discusses measurements of flammable mine gases obtained from a mine in western Pennsylvania.

Jan 1, 1992

By J. C. Cawley

Improvements in today's maintenance practices are mandatory as more complex and productive machines evolve in the mining industry. By keeping machine reliability high through improved maintenance procedures, overall mining costs can be reduced. The Bureau of Mines is investigating diagnostic maintenance systems for underground mining machinery. A hydraulic expert diagnostic system and an electric motor predictive diagnostic system have been designed and installed on a Joy 16CM continuous miner. An electrical diagnostic system has been designed and installed on a Joy 14CM continuous miner. Each system is functionally described and the relative merits of expert diagnostic systems versus algorithmic diagnostic systems are discussed.

Jan 1, 1992

By William D. Schwab

In the technical literature of 1965 and 1966, there were several papers about future power for mining and construction equipment. Most of these papers made the same predictions: •More power •Better reliability and durability •Ease of service and maintenance •Operating economy •The possibility of future environmental concern •The entrance of the gas turbine In the five years that have since passed, some of the 1965-66 predictions have at least partially come true, while others have not been fully realized. Actually the list still appears sound today. Priorities may have changed and details may be different, but the main points cover the requirements for future prime movers quite well.

Jan 1, 1971

By J. M. Rotter, R. A. Lohnes, J. Y. Ooi

Reliable prediction of wall pressures in a coal silo demands careful characterization of the stress-strain properties of the coal. This paper describes the results of triaxial compression tests on a typical fine-ground coal used in power generation and describes the fitting of several different constitutive models to the data. The fitted parameters for the constitutive models are well suited to application infinite element analyses. The different models are used to give the reader flexibility in choosing a model and to show the shortcomings of some models. To explore the quality of the fitting process, the fitted results are compared with finite element predictions of the triaxial test itself.

Jan 1, 1998

By Ken Bright

This paper is an overview of approaches to assessment of ore grade for gold and the platinum group at the exploration stage of a project. Proper sampling techhniques must be complemented by good assaying. In turn, correct assaying has its roots in thoughtful, systematic sampling and sample preparation procedures. While intricacies of the subject matter could occupy a book, we will comment on acceptable sampling approaches, outline a lab hand- ling scheme, and discuss preferred analytical methods. Pitfalls previously encountered by the mining and exploration industry will be highlighted with emphasis on a perceptive under- standing of the nature of ore occurrence. Lastly, focus will be centered on reliable assay approaches.

Jan 1, 1988

By Guido Deissnann, Jennifer L. Kirkaldy, Stephan Kistinger, Carol M. Pettit

Contaminated mine drainage presents a potential hazard for aquatic ecosystems and groundwater resources. Reliable predictions of long-term developments in seepage quality are necessary to select reasonable decommissioning options and remediation measures for waste-rock heaps during mine closure and/or mining site rehabilitation to minimize future risks and environmental hazards. Extensive geochemical modeling work was used to assess the consequences of various remediation options for waste rock heaps at a former uranium mine in Eastern Germany. The predicted contaminant discharges are used for an assessment of long- term benefits of decommissioning alternatives to derive conclusions for sustainable remediation measures using risk-based cost/benefit analyses.

Jan 1, 2000

By W. N. Marchant, P. T. Brooks, P. B. Altringer, R. O. Dannenberg

The US Department of the Interior, Bureau of Mines conducted laboratory tests to devise a process for recovering a marketable grade of tungsten from the brine of Searles Lake, Calif. The brine contains only 56 ppm W (70 ppm W03). Using ion exchange resins synthesized by USBM chemists, 98% oft he tungsten was extracted from the brine and 92% of the tungsten was recovered as a marketable iron-tungsten concentrate containing 44% tungsten as tungsten trioxide. Although major technical problems have largely been resolved, research is progressing to escalate testing in a process research unit to provide more reliable data for an economic appraisal.

Jan 8, 1979