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By R. W. Stahl, H. E. Sanford, J. B. Benson

"As movement or transportation of coal is second only in importance to actual mining, and as the latter is wholly dependent on the former, the efficiency of the haulage system often determines the efficiency of the entire plant. Safe or accident-free transportation is essential, also, because no attempt is made to divorce safety and efficiency, it being realized that they are inseparable.Most of the Ruhr mines were opened decades ago, and many features that were considered up-to-date then are now obsolete. Progress in developing haulage systems has been slow, chiefly because it would be very costly to change many to accomodate more modern equipment. These systems are being altered or modernized slowly, as capital permits. The only revolutionary changes that have been made in mine haulage are the use of larger locomo¬tives and cars, in the movement of shuttle cars, and in the adoption of skip hoisting. Most Ruhr shafts, however, will not accomodate large cars, the secondary roadways are too narrow for large locomotives, and the coal is too soft to permit skip hoisting because degradation would be too great. Therefore, notable advances have been made only at newer plants, where allowances have been made for modern equipment.The shafts are deep (average 2,300 feet) and of comparatively small diameter. The small bore was designed to reduce costs of sinking and lining. Generally, the shafts are lined throughout with masonry; however, most of the buntons and guides are wooden.The hoisting engines arc installed in masonry structures, and where more than one hoist is used they are placed on opposite sides of the shaft to eliminate as much noise as possible (fig. 1). This arrangement also prevents an engineer from acting on any signals except those transmitted to him. A few hoisting engines are mounted in the headframes (fig. 2). The hoisting engines are equipped with overwind, overspeed, and auxiliary braking devices, which are tested frequently and kept operative at all times. The signal code is displayed in view of the engineer, and a light or dial indicator informs him of the cage's position in the shaft. Many hoists are equipped with re¬cording devices, which show on a continuous chart the speed of hoisting as well as any delays throughout the 24-hour period.A Koepe system of winding is in general use because of the depth of shafts (fig. 3). With this system, a single rope passes over a single-groove, large-diameter sheave attached to the motive power, and the ends of the rope, after passing over the head sheaves, are attached to the cages. A flat tail rope suspended in the shaft and connected to the bottom of the cages serves to balance the system. Both steam and electric engines are used to activate the hoisting system, end the engines are capable of moving at least a 50-percent overload.The ropes are necessarily of large diameter (2-1/2 inches and greater), and flexibility decreases as rope diameter increases. To overcome the unwieldiness .of large-diameter ropes as shafts become deeper, a four-rope system is being tried at one mine (fig.4). In this system the load is equalized between four ropes which permits much smaller ropes to be used. All hoist ropes are inspected daily and discarded after 2 years service unless special permission for longer service is granted by the Mine Inspectorate, and then only after thorough visual and electromagnetic inspection."

Jan 1, 1950

Objective To improve seats on mine shuttle cars with ergonomic design and by reducing shock impact transmitted through the mine vehicle seat to the vehicle operator. Background Operators of underground mobile equipment, particularly shuttle cars, are often exposed to significant levels of shock and whole-body vibration. Past studies have reported that as many as one-third of underground equipment operators could be exposed to adverse levels of shock and whole-body vibration. Moreover, seats on mining equipment, historically, are inadequate relative to the ergonomic needs of the equipment operator. In the extreme, amine vehicle seat has sometimes consisted of blocks of wood or a bent steel plate bolted to the machine frame. Also, the lack of sufficient vertical clearance in some underground mines is an impediment to providing adequate shock isolation systems on mine equipment seats. Approach The NIOSH Pittsburgh Research Center (PRC) is conducting research with viscoelastic foams to improve seats on mine shuttle cars. Viscoelastic foams were used in an ergonomically designed seat to reduce the amount of shock transmitted through the mine vehicle seat to the vehicle operator. Data on selected viscoelastic foams were analyzed from laboratory shock tests at PRC. Using information from the analysis, two ergonomic seats incorporating selected foam were constructed for in-mine testing on a shuttle car (Joy 21SC) in eastern Kentucky. The shuttle car operated in a 35-in-thick coal seam with an approximate mining height of 43 in. Operational data were recorded on the ergonomic and original seats. Further, the shuttle car operator was asked to compare these seats. Results When comparing the original seat (figure 1) with the ergonomic seat (figure 2), the shuttle car operator described the ergonomic seat as generally “much better” than the original seat. The operator explained. “It’s just easy to adjust. And it’s got the lower lumbar support. And the pad is thicker. It’s just much better all the way around.” He added, “It does support you more and [there is] less shock when you hit a hole...I liked the lower lumbar support. That’s where most of your shock is at, in your lower back.” The operational data supported the operator’s comments. In the full-load case, significant improvements in isolation were achieved(down to 15 Hz) with the ergonomic seat. Additional laboratory testing of seven viscoelastic foams was done to further improve the level of isolation from shock and better characterize the material properties of each foam. Data from this testing were used in an analytical model of the seat pan isolation system. Results showed that two of the viscoelastic foams, SUN-MATE EXTRA-SOFT and PUDGEE, gave the most effective shock isolation of the seven materials tested. A composite of EXTRA-SOFT and PUDGEE foams improved the isolation characteristics of the seat pan to approximately 4 Hz. Similarly, EXTRA-SOFT by itself provided isolation to 5 Hz. These results will be validated with future in-mine measurements. Cooperative Research Opportunity NIOSH is seeking cooperators to assist in further research and development of this technology. Additional information on cooperative reseach may be obtained by contacting Jacqueline H. Jansky, Technology Transfer Officer, NIOSH Pittsburgh Research Center, P.O. Box 18070, Cochrans Mill Rd., Pittsburgh, PA 15236-0070, phone: (412) 892-6615, fax: (412) 892-6678, e-mail:jgj7@cdc.gov

May 1, 1997

By Frank E. Cash

The Bureau of Mines in its safety work has for a number of years advocated and recommended the use of permissible portable electric cap lamps for use in all mines. In the course of time required for the evolution from an unsatisfactory to an efficient and safe light, but encouraging increase in their use has been experienced in Alabama. As early as 1916, small installations of these safer lamps were made or an experimental basis by several operating companies, and the first complete mine installation eras made at the Virginia mine of the Gulf States Steel Co., July 1, 1918. From the experiments in 1316 and the complete equipment of the first mine in 1918 gradual progress has been made until there are now 30 installations with 10 operating companies; as a result 20 mines have been put entirely and 5 partly on, closed lights, and 3 companies equip their engineering departments; two installations of closed lights are maintained by other companies for emergency use. One of the mines partly on the electric cap lamp is an ore mine - the only one in Alabama (and one of the very few in the United States) that uses closed lights. ACKNOWLEDGEMENTS The full cooperation of operating officials, lapmen, and lamp representatives was given in the collection of the data in this report, and is hereby acknowledged.

Jan 1, 1928

By P. L. Sibrell

Electrorefining of Ti in nonaqueous solvents has been studied by the U.S. Bureau of mines as a method for recycling impure scrap Ti. Electrochemical behavior of Ti species was investigated using cyclic voltammetry. Research results showed that Ti metal can be dissolved in polar solvents such as dimethylformamide or dimethyl sulfoxide. However, deposition of Ti from these solvents was not successful. Several solvent systems were investigated for electrodeposition of Ti but no deposits were obtained. Reduction of Ti4+ complexes to Ti3+ proved to be straightforward, but reduction to lower oxidation states could not be confirmed. In dimethylformamide solutions, cyclic voltammetry results demonstrated the reduction of Ti to an oxidation state of less than three, but no Ti metal was identified. In dimethyl sulfoxide solutions containing LiCl, it was possible to deposit Li metal. After adding Ti salts to the solution, electrolysis quickly passivated the electrode. Deposition of Ti was also investigated in solutions of dimethoxyethane and propylene carbonate but, again, no reduction of Ti to oxidation states of less than three occurred. Therefore, the prospects for a nonaqueous electrorefining system for Ti metal do not appear promising.

Jan 1, 2010

By Stephen A. Swan

Certain types of mobile surface mining equipment are required to be equipped with rollover protective structures (ROPS) capable of protecting the operator in case of a rollover accident. The Bureau of Mines has developed ROPS performance criteria for wheeled front-end loaders. This report reviews the development of rollover test procedures and subsequent testing of ROPS for 52,000-, 286,000-, and 390,000-lb gross vehicle weight (GVW) loaders. The program consisted of both dynamic (roll) and static tests to assist in the development of the ROPS performance criteria. Each test included extensive instrumentation and photographic documentation to fully evaluate the performance of the ROPS. Data summarizing side, longitudinal, and vertical force and deflections are included. The data indicate that for loaders in excess of 240,000 lb, GVW, a side force-to-mass ratio of 1.0 and an energy-to-mass ratio of 6.0 appear to be adequate criteria to protect an operator in the event of a 5400 rollover. For smaller machines, Society of Automotive Engineers (SAE) 11040 performance criteria provide adequate protection. Longitudinal loading, though not ad-dressed in previous ROPS performance criteria, was shown to be a potentially significant factor in ROPS failure. Longitudinal loading and energy criteria equal to 80 pct of side loading criteria are recommended.

Jan 1, 1988

By William J. Campbell

This Bureau of Mines report describes a study conducted to determine the relationship of mineral habit to particle size and shape characteristics for prismatic, acicular, fibrous, and asbestiform varieties of tremolite. Particle measurements were made with the petrographic microscope at X 1,250 and the scanning electron microscope at magnifications up to X 10,000. All of the varieties of tremolite, upon Wiley milling, produced a significant percentage of particles that meet the Federal regulatory criteria for counting as asbestos fibers. However, only the asbestiform variety gave milled particles that fell into a size range of >10 µm in length and <0.5 µm in width; some medical scientists consider this range significant for production of adverse health effects.

Jan 1, 1979

By Ott F. Heizer

This paper describing the practice at the tungsten concentrator of the Nevada-Massachusetts Co., Inc., at Mill City, Nev., is one of a series being prepared by the Bureau of Mines on milling practices, methods, and costs in the United States. The ore, which contains about 1.10 per cent of scheelite (CaW04), is concentrated on tables and by means of a magnetic separator and roasters. A product containing 70.43 tungsten trioxide is shipped. The plant was designed for a capacity of 100 tons per 24 hours, but at present 142 tons of ore are milled per day. The author acknowledges the assistance of William O. Vanderburg, associate mining engineer, U. S. Bureau of Mines, in preparing this paper.

Jan 1, 1930

By Hillary W. St. Clair

Reaction rate coefficients were determined from analyses of the effluent gas for the reduction of granular ferrous oxide to metallic iron by passing carbon monoxide through a packed bed of oxide at a controlled rate in the temperature range 1,000° to 1,300° C. Coefficients were determined by the comparison of observed analyses and calculated analyses using a mathematical model that takes into account the nonuniform composition of both the solid oxide and the gas. A method is also given for finding the value of the rate coefficient that best fits the observed data.

Jan 1, 1968

To determine the effectiveness of multiple types of fire sensors for early and reliable mine fire detection. Background The National Institute for Occupational Safety and Health (NIOSH) has evaluated the effectiveness of multiple types of fire sensors for early mine fire detection and nuisance signal discrimination. Reliable early fire detection in underground mine can be hindered by false fire alarms produced by carbon monoxide (CO) and smoke particulate emissions from diesel equipment, welding, and metal-burning activities. Another false fire alarm source is the cross-interference of hydrogen (H2) produced by battery-charging operations with a CO sensor&apos;s chemical cell. Workers can learn to ignore repetitious "false" alarms associated with these emissions. This jeopardizes their safety in the event of a mine fire.

Sep 1, 2002

By J. William Ganser

This paper is one of a series being prepared by the U. S. Bureau of Mines describing mining and milling methods and costs at cement-plant quarries throughout the United States. These papers are designed to disseminate technical information regarding the methods used. The cost tabulations represent local operating expenditures only and not total production costs. It is recognized that publication of total production costs might in many instances cause embarrassment to individual producers as well as to the industry as a whole. On the other hand, operating costs are essential to the technical discussion and study of the methods employed. The attention of the reader is specifically palled to this differentiation in order that no misunderstanding of the scope of the cost tabulations shall ensue. ACKNOWLEDGMENTS The author wishes to acknowledge the assistance of Fred Burkett, civil engineer, and F. O. Londrey, chief clerk, of the Trinity Portland Cement Co., for assistance in preparation of this paper, "The Geology of Dallas County. 1918," Bulletin 1818, Texas Geological Survey, Austin, Tex., by E. W. Shuler, was also freely consulted.

Jan 1, 1931

By O. C. Blade

This report on the properties of motor fuels sold through service stations in the United States was made in accordance with a cooperative agreement between the American Petroleum Institute and the Bureau of Mines of the United States Department of the Interior. By agreement with the American Petroleum Institute, identification of the Items is confidential. It present&apos;s analytical data for 4,608 samples, representing the products of 101 companies. The samples were collected during December 1956, January and February 1957. As in previous surveys, the gasolines covered by this survey include those from both large and small suppliers. The data were obtained by laboratories of various refiners, motor manufacturers, and chemical companies and submitted to the Bureau of Mines for compilation. A list of the Notional Motor Gasoline Survey reports published during the post 10 years is given on page 5.

Jan 1, 1957

By H. C. Ko

Calorimetric determinations of low-temperature heat capacities and the standard enthalpy of formation were made by the Bureau of Mines for aluminum sulfide, A12S3. The standard entropy (S°), enthalpy of formation (?Hf°), and calculated Gibbs energy of formation (?Gf°) at 298.15 K are 27.93±0.05 call deg-mole, -155.6±0.9 kcal/mole, and -153.0±1.0 kcal/mole, respectively.

Jan 1, 1976

By E. A. Anundsen

The prevention of accidents is considered a necessity at all branches and divisions of the Phelps Dodge Corporation copper-producing operations, and since there is a continual exchange of data on safety accomplishments between the various units, their safety programs are fundamentally similar. Variations in accident-prevention methods result from a difference in emphasis rather than from a difference in the elements themselves. The main copper-producing operations of the corporation ore conducted in Arizona and distributed as follows: Copper Queen Branch, mines division, Fisbee, and smelter division, Douglas, Aria.; Morenci Branch, mines division, Morenci, and smelter division, Clifton, Ariz.; New Cornelia Branch, Ajo, Ariz.; and United Verde Branch, mines division, Jerome, and smelter division, Clarkdale Ariz. As it is not feasible to describe here the safety programs of all branches and divisions, the program at the Clarkdale smelter has been selected for discussion. The United Verde Brach includes the mine and smelter purchased by the Phelps Dodge Corporation in February 1935 from the United Verde Copper Co. The mine at Jerome and the reduction works at Clarkdale are designated, respectively, as the mine and smelter divisions.

Jan 1, 1939

By P. M. Ambrose

This report describes an accident, which took place in the Chemical Corrosion Laboratory at the College Park, Md., Station of the Federal Bureau of Mines. The accident occurred while Walter L. Acherman, chemist, was performing a routine manipulation during a corrosion experiment involving commercially pure titanium and red-fuming nitric acid. There was a sudden and very violent reaction, and a large quantity of acid was thrown in the face and over the body of Acherman, causing serious injury. L. B. Golden, chief of the Chemical Corrosion Section, was exposed to nitric acid fumes during the ensuing rescue and first-aid operations and died on January 25, 1954. According to the medical report, the direct cause of Mr. Golden&apos;s death was pulmonary edema and confluent bronchopneumonia; the contributary cause, was inhalation of fumes from red fuming nitric acid. The following employees of the College Park Station contributed to this report by supplying information on the accident and assisted in the rescue operation: L. B. Golden, chief, Chemical Corrosion Section; T. E. Green, chemist; Robert Warf field, chemist; L. A. DeVivo, laboratory mechanic; D. W. Chalkley, laboratory mechanic; E. H. Neagle, laboratory welder; and R. L. Heath, laboratory general mechanic.

Jan 1, 1955

By Ted C. Briggs

Twenty-two compressibility runs were made with helium over the temperature range -5° to 80° C and at pressures to 800 atmospheres. A Burnett apparatus was used. Data from the runs were fitted to a fourth degree polynomial equation of state in the pressure and a weighting factor of Pr-3/4 was used. All data for a particular isotherm were treated simultaneously. A temperature function was found to represent the parameters B and C. Compressibility factors determined by this investigation are believed to be accurate to better than 0.05 percent.

Jan 1, 1970

By R. V. Higgins

This report presents the results of a study of gas injection in the Upper and Lower Terminal zones in fault block VB and in the Upper Terminal zone in fault block VI, Wilmington field, California. This report is based on data obtained to January 1956. Earlier studies of gas injection in other California fields have been reported .3/ The Upper and Lower Terminal zones, fault block VB, have been producing oil since 1945 and the Upper Terminal zone, fault block VI, since 1948. Before starting the gas-injection project, the expansion of dissolved gas was the principal mechanism moving the oil to the wells. Gravity drainage and an edgewater drive also have contributed to the movement of the oil to the wells. When the gas injection was begun, the reservoir pressure and the oil production had declined appreciably. Gas injection was started in the Upper and Lower Terminal zones, fault block VB, in May 1953 and in the Upper Terminal zone, fault block VI, in October 1953.

Jan 1, 1957

By Barry W. Klein

The U.S. economy was considerably stronger in 1976 than in 1974 or 1975. Real gross national product (GNP) rose sharply in the first quarter of 1976 and then increased at a more moderate rate for the remainder of the year. The unemployment rate fell until June and then increased for moat of the remainder of the year, finishing at the same rate as it had started the year. The inflation rate continued to decline in 1976. Reasons for the relatively low rate (compared with those of 1974 and 1975) included small increases in food prices and only moderate increases in energy prices. Total U.S. output measured in terms of GNP increased 11.6% in 1976. Real GNP in 1972 constant dollars rose 6.2%. Inflation as measured by the implicit price deflator increased 5.1%. In real terms, gross private domestic investment for residential structures rose 22.7% in 1976 after declining 14.7%a in 1975; State and local Government expenditures increased 1.4% in 1976; and personal consumption expenditures for services rose 4.5%. The Federal Reserve Board (FRB) index of industrial production increased 10.2%.

Jan 1, 1978

By H. R. Babitzke, H. Kato, R. E. Siemens, G. Asai

The purpose of this investigation was to develop a wide variety of columbium and tantalum alloys and to determine their suitability for use at elevated temperatures . Sixty - nine columbium and tantalum alloys were investigated . For this study , columbium was alloyed with two or more of the following : nium, tungsten , vanadium , titanium, and zirconium . Tantalum was alloyed with vanadium or hafnium, or hafnium and carbon . The fabricability was determined by an arbitrary procedure . Hardness measurements , elevated - temperature tensile properties , and oxidation- resistance studies were made . Of the alloys studied , Cb - 15 Hf - 5W, Cb - 15Hf - 5W- 10Ti , Cb - 15Hf - 10W- 10Ti , Cb - 10V - 5W, Ta - 30V , and Ta - 20 to 33Hf exhibited excellent high - temperature properties . These alloys were not only easy to fabricate , but they also had good oxidation resistance and excellent high- temperature strength .

Jan 1, 1964

By R. J. Heemstra

A method was developed for calibrating photographic emulsions and retrieving working curves for emission spectrography. The values obtained from a digital readout or a recorder chart of a comparator-microphotometer are converted to light intensity values using an emulsion characteristic curve derived from a quartic polynomial preliminary curve. The characteristic curve, consisting of Seidel transform versus the logarithm of intensity, is split into two cubic polynomials at the zero value of the transform, resulting in eight emulsion calibration coefficients. These methods allow use of the calibration curves even at very small and very high intensities, thus extending the range of analysis. Use of a small computer allows rapid calculations. A computer program was written to formulate, code, and file each working curve along with its statistical error. Proper coding of the input data permits the direct printout of the concentration of the elements under investigation.

Jan 1, 1970

By H. O. Poppleton, F. E. Block

This investigation was made to develop a method of preparing high - purity thorium metal in quantities up to 20 kilograms per batch . Several methods for the preparation , purification , and reduction of thorium tetrachloride are discussed . Thorium tetrachloride was prepared by chlorination of decomposed thorium nitrate or oxalate with carbon tetrachloride or phosgene . tion of the crude tetrachloride was achieved by multiple distillations or by filtration of the molten chloride . It was found that high - purity thorium metal could be prepared by sodium reduction of thorium tetrachloride if chloride of sufficient purity were available . Byproduct salts and excess reductant were removed by vacuum distillation , and the resultant thorium metal sponge was consolidated by consumable - electrode or fixed - electrode arc melting . It was demonstrated that metal prepared by this method could be fabricated into bar , rod , or sheet , at room temperature .

Jan 1, 1964