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By John T. Metcalf

The assembly procedures for nine different wire rope terminations used in the mining industry are presented in a format and manner to facilitate training and to provide points where inspection of the termination should be performed. The nine terminations addressed are: Flemish Loop with Steel Sleeve & Thimble, Flemish Loop with Steel Sleeve, Wedge Socket, Swaged Socket, Turn Back Loop with Sleeve & Thimble, Thimble Splice with Four Tucks, U-Bolt Clip & Thimble, Zinc Poured Socket, and Epoxy Resin Poured Socket. The manual was prepared to be used primarily for field type mining operations or training where high capacity machinery is quite limited. It is nut the intent of this manual to suggest that the procedures presented are those to be used by manufacturers or other commercial enterprizes. A different set of procedures may be more appropriate where ideal space and equipment resources are available. The assembly procedures were derived from standard industrial practice, manufacturer's recommendations, and the open literature on the subject. These same procedures were used to prapare test specimens for an extensive series of pull and axial fatigue tests. The results of these tests indicate that these procedures are satisfactory in all respects. This manual is to be used as part of a complete training program. Although a brief glossary is included, there has been no attempt to make this a primer on wire rope. The selection of wire rope termination hardware, like the selection of the wire rope, is a subject not covered by this manual. The reader is cautioned that there are various sources for such hardware and this selection must be done carefully.

Jan 1, 1978

By Fred N. Kissell

In This Chapter [The explosibility of methane gas mixtures Effect of pressure and temperature on explosibility Less common sources of methane ignitions The amount of methane stored in coal Forecasting the methane emission rate Layering of methane at the mine roof When the recirculation of mine air is hazardous The importance of higher air velocity in preventing methane explosions and Mine explosions, barometric pressure, and the seasonal trend in explosions] Dealing with methane in mines and tunnels requires knowledge of the circumstances under which dangerous accumulations of methane are likely to occur. This knowledge involves the properties of the gas itself, an awareness of where these accumulations are likely to occur, and facts on how methane mixes safely into the mine air. The other chapters in this handbook address the handling of methane under a variety of specific circumstances, such as at continuous miner faces or coal storage silos. This chapter addresses some broad concepts that serve as a foundation for the suggestions provided in other chapters. THE EXPLOSIBILITY OF METHANE GAS MIXTURES Methane entering a mine or tunnel often enters as a localized source at high concentration. Figure 1–1 depicts a cloud of methane being diluted into a moving air stream. In this illustration, methane enters the mine from a crack in the roof. As the methane emerges from the crack, it progressively mixes with the ventilation air and is diluted. In the event that this progressive dilution reduces the concentration from 100% to 1%,2 as shown in Figure 1–1, the methane passes through a concentration range of 15% to 5%, known as the explosive range. In the explosive range, the mixture may be ignited. Above 15%, called the upper explosive limit (UEL), methane-air mixtures are not explosive, but will become explosive when mixed with more air.

Jan 6, 2006

By Guenter F. Lehmann

This report summarizes the results of the development and testing of a prototype monorail suspended bridge conveyor (MBC) system as a method of continuous haulage In underground mining applications. Included are the results of full scale, surface and underground testing of the complete MBC system. Conclusions drawn from these results, together with recommended modifications, supports the viability of the MBC system.

Jan 1, 1988

By W. R. K. Wu

Results of linear correlations of two to four variables by the least-squares method are presented. The variables include 63 parameters representing coal composition, coal plasticity, and coke strength. The composition parameters are on chemical analyses; the plasticity parameters, on three plastometer and dilatometer tests and four miscellaneous tests; and the coke-strength parameters, on three ASTM indices. Seventy-two to eighty-four plastic coals were used in the plasticity and carbonization tests, which together form the basis of this report; 43 nonplastic or weakly plastic coals were used in the coal-band studies. Plots of relations between volatile matter, carbon, and oxygen contents of 1,860 U.S. coals and the 84 coals used are shown. Similar plots between volatile matter and hydrogen or atomic H/C of the 84 coals are also included. Significances of regression coefficient signs for coal composition parameters in the significant correlations found are discussed. Based on these significances, the following relations are shown: (a) coke strength versus average aromaticity, or mineral matter content, of the parent coal; (b) characteristic temperatures of the plastometer and dilatometers, the free-swelling index, or the Gray-King type versus average hydroaromaticity of the coal; and (c) nontemperature parameters of the plastometer and dilatometers versus the physical properties of a certain group of compounds from thermal decomposition of coal. Similarly, significances between the positions of coals in the coal band and the aforementioned relations are also discussed. A structural theory of coal plasticity is proposed. Applications of the correlation results are discussed. Composition parameters, such as carbon, atomic H/C, and calorific value may be used as a basis for selecting coking coals for stronger coke. Plasticity parameters, such as the end temperatures of the plastometer and dilatometers and the free-swelling index, may be used for the same purpose. Based on the best correlations found, coke-strength indices may be estimated to within 4 to 8 units of the observed values; the end temperatures of the plastometer and dilatometer tests, 5° to 10° C.; and the free-swelling index, within 1 unit. Accuracies of all these estimated values are examined, based on the experimental errors of the data involved. Finally, estimations of plasticity parameters from one test with those from others are shown.

Jan 1, 1971

Reduce accidents associated with handling of the electrical trailing cable and the water hose on mining equipment. Approach Two reels were mounted on a loading machine to store and release the lines as required during face operations. How It Works A hydraulic motor, which is actuated by a treadle valve in the operator's cab, controls the reel on which 50 feet of electrical power cable is stored. A spring motor resists unwinding of the other reel on which 50 feet of water hose is stored. Both reels are mounted on the right rear of the loading machine. See Figure 1. Following common mining practice, the cable and hose are anchored to fixed points at the first intersection outby the face. Tramming forward causes the cable and hose to be pulled from the reels. Depressing the treadle valve causes the electric cable reel to turn and wind-in any slack in the cable. The spring tension on the water hose reel automatically rewinds the water hose when the loader is trammed in reverse.

Jan 1, 1978

By R. Karl Zipf, Kousick Biswas

The main objective of occupational health and safety research is to minimize or eliminate the events that may cause fatal or non-fatal injuries to human workers. A commonly used technique is to devise an “incident prevention plan”, which is more often the product of thorough investigations of past reported incident events. Incident documentation and methodical reporting and systematic and thorough data collection, often help identify the root cause of the incident – in other words, the etiology of the incident. These retrospective analyses of the incidents can efficiently identify the future steps to take to achieve the objective of minimizing occurrence of “events of interest”. This paper introduces a novel technique – “Taxonomic Analysis”, which identifies the root causes of an event (an incident in this case) and can provide future direction for corrective measures to reduce the probability of occurrence of the event. A taxonomic analysis involves systematic and organization of data based on observation, description, and classification. This paper utilizes the rock fall related incident narratives, available with the Mine Safety and Health Administration (MSHA) database (1984-1999), for a taxonomic analysis. The study found that 67.6% of groundfall incidents occurred in supported areas with the remainder (32.4%) in unsupported areas. Some form of rock mass failure appears to cause about 50% of groundfall incidents, although in 39.7% of the overall groundfall incidents or two-thirds of those involving rock mass failure, the exact nature of the rock mass failure could not be determined from the narratives. Human activities factors such as scaling or barring down, drilling or bolting, and setting timbers or cribbing accounted for another 34.5% of the groundfall incidents. Finally, support system failures made up the remaining 15.5%. Results from this taxonomic analysis may suggest focus areas toward which preventive measures and future research activities could concentrate.

By Charles B. Kenahan

Vanadium is subject to only light corrosion in phosphoric acid at temperatures up to 60° C. and has a moderate corrosion rate in this acid at 100° C. It is relatively corrosion resistant in sulfuric and hydrochloric acids up to 60° C, but corrodes rapidly at 100° C. It corrodes rapidly in dilute nitric acid at 35° C. Vanadium is almost inert in 10-percent solutions of formic, acetic, lactic, tartaric, and citric acids; in 9-percent oxalic acid it corrodes slowly up to 60° C. and rapidly at 100° C. Vanadium is resistant to corrosion in substitute ocean water, tapwater, and in 3-percent sodium chloride and 10-percent sodium hydroxide solutions. It is readily attacked, however, by 20-percent ferric chloride, 20-percent cupric chloride and 5-percent mercuric chloride solutions. Vanadium is protected by contact with magnesium, aluminum, and steel SAE 4130 in substitute ocean water, by magnesium and aluminum in 3-percent sodium chloride solution, and by magnesium in tapwater. Vanadium protects copper in substitute ocean water. When vanadium and stainless steel are coupled in sulfuric acid solutions, both metals are usually unaffected by contact, whereas the corrosion rate of titanium in sulfuric acid is greatly reduced by contact with vanadium.

Jan 1, 1962

By E. L. Garton

Bureau of Mines routine crude-oil analyses of 88 samples from 60 fields are presented in this report. Similar analyses from other fields in California have been published in previous reports listed in the appendix, page 52. Yearly production of crude oil in California and the percentage of United States production represented by California production for 1948-54 are given in table 1. [ ] Analyses in this report are of samples from the fields listed in table 2, with production data for 1953, cumulative production through 1953, and year of discovery of each field. Information regarding the source and general characteristics of the samples is included in table 3 with a summary of analytical and computed data.

Jan 1, 1956

By C. E. Arrington, A. C. Rice

"Part 1. REDUCTION AND USE OF OXIDANTSSUMMARYA study has been made of the volumetric determination of molybdenum by reduction in the Jones reductor, receiving the reduced solution in a mixture of ferric alum and phosphoric acid, and titrating with standard oxidizing agents. In addition to potassium permanganate, which has long been utilized for this titration, potassium dichromate and ceric sulphate have been found to be applicable. The latter oxidants have been found to be especially useful in the form of dilute solutions for the determination of small amounts of molybdenum. The tests revealed that certain internal indicators give excellent results in these titrations.Reason for These ExperimentsThe following study was initiated with the hope of providing the mining and metallurgical industries with an accurate and rapid technical method for the determination of molybdenum in such low-grade materials as ores, rocks, tailings, steels, and alloys containing less than 0.3 percent molybdenum. Although the experimental work was designed with this purpose in mind, many of the results are applicable to material containing a higher percentage of molybdenum.While the Bureau of Mines had an experiment station in Colorado, considerable analytical work was done on what were then (up to about 1923) classed as rare metals. One of these was molybdenum; and in Bulletin 212, Bonardi's (1) 3/ 60-page chapter covered all methods for the analysis of molybdenum."

Apr 1, 1939

By C. S. Compton, D. R. Dolinar, D. C. Oyler

More than 80% of U.S. roof bolts are fully-grouted, but about 1500 roof falls are reported each year. Anchorage failure of a fully grouted bolt can occur when the roof is active near the top of the hole. This paper reports on an extensive series of short-encapsulation pull tests (in which the bolts are installed with only 1 ft of resin) that were conducted in the National Institute for Occupational Safety and Health (NIOSH) Mine Safety Research Laboratory and operating mines in WV and PA. The tests confirmed that poor anchorage can been countered under some weak rock conditions. Suggestions for improving anchorage are included.

By R. R. Sayers

Radioactivity, the property of radium that led to its isolation more than 30 years ago, is the characteristic that makes it of value in the treatment of disease. Tyler3 gives the following brief history of the investigation: The way to the discovery of radium was opened in 1895 by Rontgen, who found that the glow from a Crooke's tube contained penetrating rays, which .he called X rays. Prof. Henri Bequerel, while investigating the effect of various phosphor¬ escent substances, found that uranium salts produced photographic impressions even when enveloped with opaque substances. To Marie Sklovouski, a young Polish student, who later became Madame Curie, Professor Bacquerel delegated the task of learning how and why uranium possessed power to emit these peculiar rays, which he had proved to be electrical in character. Madam Curie, examining by electri¬ cal methods the radioactivity of a large number of minerals containing uranium and thorium, discovered that some specimens of pitchblende had about four times the activity of the metal uranium; that chalcolite, the crystallized phosphate of copper and uranium, was twice as active as uranium; that autunite, a phosphate of calcium and uranium, was quite as active as the same weight of pure uranium. In order to check these discoveries, she prepared chalcolite artificially, starting with pure products, but found that this artificial chalcolite had only the acti¬ vity represented by its composition, or, roughly, 40 per cent of the activity of uranium. This led to the conclusion that there was some element or substance in the residue from uranium minerals that possesses a high degree of activity. After an exhaustive chemical investigation of pitchblende from Joachimsthal, she found that this mineral contained not only uranium but also another radioactive sub¬ stance, to which she gave the name of polonium, in honor of her native land. Later in 1898, Monsieur and Madame Curie found still another element, which, when brought to a state of concentration, was several million times as active as uranium, and to this was given the name of radium. Debierne afterwards found a fifth radio¬ active substance, actinium; and in 1906 Boltwood isolated the metal ionium. Strict¬ ly pure radium chloride was first produced in 1902. The first radium was produced commercially from the uranium residues obtained from the mines of Joachimsthal, Bohemia. Tyler calls to attention that, as the ores were a government monopoly, search was begun at once for sources in other parts of the world. As a result, radium-containing ores have been found in about 10 countries.

Oct 1, 1932

By D. H. Platt

Gypsum and gypsite, used in the manufacture of plaster and plaster products, have been mined from deposits near Acme, Hardeman County, Tex., for more than 30 years. The Certain-toed Products Corp., 120 East Lancaster St., Ardmore, Pa., operates the Acme, Tex., mine. Underground hauling was done with storage-battery and Diesel-electric-powered shuttle cars. Many mining companies and individuals have manifested interest in all types of equipment powered by Diesel or Diesel-electric units, as attested by the recent increase in use of Diesel-powered equipment in underground metal and nonmetal mines. The purpose of this paper is to describe the manner in which a storage battery-powered Joy Model 60D2 shuttle car was converted to Diesel-electric power. The conversion was made, at the instance of the operating company, by Stewart & Stevens on Services, 4801 Lemon Ave., Dallas, Tex. This is believed to be the only such converted shuttle car in use.

Jan 1, 1950

By Ren G. Dong, John Z. Wu, Daniel E. Welcome, Kristine Krajnak

Although the exact mechanisms underlying vibration white finger (VWF) are not clear, it has been speculated that VWF is associated with variations of the blood flow patterns due to the physical damage and/or degeneration in neural and vascular tissue caused by vibration loading [1]. Excessive dynamic deformation of the soft tissues in the fingertip under vibration loading is believed to induce multiple occupation-related hand/finger disorders. However, the in vivo distributions of the dynamic stress/strain of the tissues in the fingertip under vibration conditions have not been studied because they cannot be measured experimentally to date. The goal of this study is to analyze, theoretically, the location and frequency-dependent dynamic deformation of the soft tissue in the fingertip during vibration exposures. [ ] Methods The fingertip considered in the model is the distal phalanx, the portion from the distal end of the fingertip to the distal interphalangeal (DIP) joint articulation (Fig. 1). The external shape of the fingertip was determined using a smooth mathematical surface fitting to the observed fingertip shapes. The fingertip surface was then scaled to the dimensions of a typical male index finger: length 25 mm, width 20 mm, and height 18 mm. The fingertip was approximated to be symmetric, such that only a half of the fingertip was considered in the FE modeling. The fingertip was assumed to be composed of outer and inner skin layers, subcutaneous tissue, bone, and nail. The soft tissues (inner skin layer and subcutaneous tissues) were assumed to be nonlinearly elastic and viscoelastic, while the bone, nail, and outer skin layer were considered as linearly elastic. The simulations were conducted using a displacement-controlled protocol in two stages. First, the fingertip was statically pre-compressed. The contact plate was first displaced towards the finger to achieve a predetermined value of tissue deformation (i.e., 0.5, 1.0, 1.5, and 2.0 mm). Second, the steady-state dynamics responses of the fingertip were analyzed using a linear perturbation procedure. The fingertip was subjected to a continuous harmonic excitation (magnitude 0.5 mm) from the contact interface. The dynamic analysis was performed in a frequency domain ranging from 16 to 2000 Hz. The frequency-dependent distributions of the vibration magnitude and dynamic strain magnitudes in the soft tissues are investigated. Results Typical simulation results for the frequency-dependent distributions of the vibration magnitude in the soft tissues are shown in Fig. 2 (figures show the results with a pre-compression of 2.0 mm). The vibration magnitude at the contact surface is 0.5 mm (specified) for all frequencies, while the vibration magnitudes in the soft tissues are location- and frequency-dependent. It is clear that the fingertip has a major resonance around 125 Hz, at which the vibration magnitudes in the soft tissues are over four times greater than that of the contact plate (0.5 mm). It is interesting to observe that, at this resonant frequency (125 Hz), the soft tissues at the tip has the maximal vibration magnitude while the regions near the contact

Jan 6, 2006

By E. M. Frost

"A new apparatus has been devised for quickly and precisely analyzing natural gas for its helium content. The following outstanding advantages make it far superior to any equipment now available for the purpose.3/4/5/6/1. It enables more rapid determinations to be made.2. It has far greater sensitivity than previous apparatus. 3. It is portable.Fifty or more samples may be analyzed in an 8-hour day with the new apparatus and procedure. A maximum of about 10 samples per day could be analyzed with previous apparatus. In the apparatus described, the volume of pure helium obtained from a sample is determined by measuring the pressures created by that pure helium when it is expanded into a constant calibrated volume. In older methods the pure helium separated from a sample is pumped into a burette and measured at atmospheric pressure. The new apparatus and Procedure used with it reduce the average time for an analysis from about 40 minutes to less than 10 minutes,Samples containing a few thousandths of a percent helium may be analyzed as readily as samples containing 1 percent or more, This was not possible with former apparatus. Duplicate samples containing a few thousandths of a percent helium have been analyzed, results checking to one ten-thousandth of a percent. Attempts to measure a corresponding volume of helium in a burette at atmospheric pressure become futile. The ability to determine very small quantities of helium has become of great importance recently in gas- and oil-field engineering studies such Os the utilization of helium as a tracer gas in following the movement of gases through underground structures.A complete apparatus was recently carried more than a thousand miles in a passenger automobile. It arrived without breakage, was .set up and ready to make an analysis in a few hours. .Former apparatus was not portable. The portability of the present apparatus permits taking the apparatus to the field for more efficient prosecution of field engineering problems. The only services required in the field are electricity, tap water, and a source of liquid air or liquid nitrogen.The principle involved is based upon the fact that large volumes of all the constituents usually found in natural gas, except helium, are adsorbed quantitatively on cocoanut charcoal that has been cooled to the temperatures of liquid air. A volume of sample is measured and transferred to a tube of cocoanut charcoal maintained at the temperature of liquid air. After adsorption of all the constituents other than helium, the charcoal tube is connected to a sensitive pressure-measuring device, and the Percentage helium originally in the sample is calculated from two pressure readings and the volume of the original sample."

Jun 1, 1946

By A. N. Baldwin

This report documents the work performed under Bureau of Mines Contract J0265029 to study and develop two innovative mining systems: ? An underground auger capable of augering into the right and left ribs without repositioning the machine ? A conventional mining system employing recently developed innovative machinery. The report is separated into two volumes to document the two studies separately. Volume I describes work performed and the recommended concept for a bidirectional auger. Volume II describes the studies of mining equipment performance and mining plans developed to determine a conventional mining plan offering improved productivity.

Jan 1, 1977

By Charles D. Litton

This U.S. Bureau of Mines report details the results of a series of large-scale experiments where small coal fires were used to ignite the conveyor belt at air velocities ranging from 0.76 to 6.1 m/s. In the tests, electrical strip heaters imbedded within a pile of coal were used to heat the coal to a point of flaming ignition. The flaming coal subsequently ignited the conveyor belt located approximately 5 to 10 cm above the coal pile. During the tests, temperature, CO, and smoke levels were continuously measured in order to determine both alarm time and level as the fire intensity progressed through the stages of smoldering coal, flaming coal, and flaming coal plus flaming belt. Analysis of the data leads to certain conditions of air velocity and sensor alarm levels that are required for early detection of conveyor belt entry fires. Two nomographs are presented, which define sensor alarm levels and sensor spacings as a function of belt entry cross-sectional area and belt entry air velocity.

Jan 1, 2010

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 Paul T. Allsman

This paper gives the cost and describes the mining of 55 tons of nickel-bearing rock by hand methods from a prospect in southern Nevada, June 15, 1937, by the Mining Division of the Bureau of Mines. The geology, mineralogy, and problems related to future development also are discussed briefly. The main object was to obtain a 55-ton sample within the limited period during which funds were available; little time was available to make a first-hand detailed study of the possibility of commercial ore deposits being found. The sample was desired by the Metallurgical Division of the Bureau for experimental purposes at the Electro-Metallurgical Station at Boulder City, Nev. The term "ore" is used loosely in the following discussion to designate dike material containing nickel and copper, without consideration of its commercial value. ACKNOLEDGMENTS Material concerning the geology and mineralogy of the prospect and district as obtained from Geological Survey publications by Bancroft3/and Longwell4/.

Jan 1, 1938

By G. R. Hopkins

[A new record in fuel efficiency at petroleum refineries was established in 1939, when a the average e B.t.u. requirements per barrel of crude oil processed declined to a new low of 557,000 B.t.u. (see fig, 1).]

Jan 1, 1941

By Deno Pappas, Chrisropher Mark, John Rusnak, Linda McWilliams

Mine planning for a new reserve is based on information obtained from exploratory coreholes. A critical component of an exploration program is the geotechnical evaluation. Poor assumptions about roof conditions greatly add to the risks of mining. Rock mechanics testing is central to a geotechnical exploration program. Typically, 3 to 5 uniaxial compressive strength (UCS) tests are made to characterize a particular roof unit at a given corehole. The average (mean) of these tests is taken as “The UCS” for that location. Isopach contour maps are then used to show spatial trends in roof strength. Two issues are raised by this traditional approach. The first is due to the large variability in UCS values that is typical even within a single unit from a single hole. The average UCS might be higher at Corehole A than it is at Corehole B, but the difference may not be statistically significant. The second issue is whether widely spaced coreholes can identify valid spatial trends in rock strength. The answer depends upon whether rock strength changes over distances that are longer or shorter than the corehole spacing. This is a classical geostatistical problem. While geostatics have been used to investigate many coal quality parameters, they have seldom been used to evaluate rock strength. This paper describes an extensive investigation of these issues conducted by the National Institute for Occupational Safety and Health (NIOSH) in collaboration with Peabody Energy. The study employed the Peabody Rock Mechanics Data Base which contains more than 10,000 individual test results. Data from four important roof units were subjected to statistical analysis: • Brereton Limestone above the Herrin 6 seam (Illinois) • Turner Mine Shale above the No. 9 Seam (Kentucky) • Sandstone above the Eagle Coal (West Virginia) • Shale above the Eagle Coal (West Virginia) The study did not find significant spatial trends in rock strength in any of the cases. Perhaps there are none, or perhaps the exploration coreholes were just too far apart to see them. These results have valuable implications for the design of geotechical exploration programs.