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By E. P. Hayes

This report supplements the date contained in Bureau of Mines Information Circular 6156, "Special features of core drilling in the salt beds of Western Texas and New Mexico," by J. S. Wroth. That circular dealt with the drilling of the first 12 of the 24 potash tests made by the U. S. Bureau of Mines in cooperation with the U. S. Geological Survey; this report is concerned with the drilling of the last 12 tests. ACKNOWLEDGMENTS The writer is indebted to R. E. Heithecker, the Bureau of Mines engineer who had charge of the drilling of tests 13 to 17, for his well-prepared records on the drilling of these tests.

Jan 1, 1933

By A. A. Berk

In the course of a study of the formation of external deposits on tubes in water-tube boilers it became desirable to determine the sulfur dioxide (SO2) and sulfur trioxide (SO3) in the Due gases. Determinations made by the A.S.M.E. method for SO2 and SO3 in gaseous products of combustion did not give accurate results. It was found that minute quantities of copper, present in the flue gases from the coal in use, caused oxidation of sulfite in the absorption bottle and that the carbon dioxide (CO2) in the flue gases caused high values for SO2. The A.S.M.E. test procedure was revised to prevent oxidation of sulfite in the absorption bottle and to allow for the effect of CO2; subsequent analyses of flue gases produced reliable results. The revised procedure is described.

Jan 1, 1950

By Charles D. Litton

This U.S. Bureau of Mines report describes the results of two large-scale tests conducted to evaluate a prototype nitric oxide (NO)-compensated carbon monoxide (CO) fire sensor, developed by Carnegie Mellon Research Institute (CMRI). In the tests, small coal fires were allowed to develop in the presence of diesel exhaust at relatively low ventilation airflows. These tests compared the response of the CMRI fire sensor with that of other fire sensors, including the Bureau's diesel-discriminating smoke detector. During the tests, CO, NO, and smoke levels were continuously monitored in order to determine the sensor alarm times and gas levels as the fire developed. The data indicated that the NO-compensated CO fire sensor was capable of suppressing the CO produced by a diesel engine and that the sensor responded reliably to the CO produced from the test fires. The tests also showed that the Bureau's diesel-discriminating smoke detector alarmed earlier than the prototype NO-compensated CO fire sensor.

Jan 1, 1993

By M. M. Tilman

The Bureau of Mines conducted research to determine the feasibility of strengthening experimental magnesium-base sheet alloys by strain softening induced by controlled cold rolling followed by selective heat treatment. Relatively small alloying additions having potential for producing strain softening were selected from metals that are readily avail-able. Tensile properties comparable to minimum properties of the most commonly used magnesium-base sheet alloy AZ31B, in the H24 condition (strain-hardened and partially annealed), were obtained in an Mg-IMM (mischmetal)-O.5Mn alloy after strain-softening rolling followed by heat treatment. Tensile properties of the experimental alloys in certain conditions are also compared with minimum tensile properties of other standard magnesium sheet alloys. Incidental to the principal objectives, apparent superplastic behavior was observed in three experimental magnesium-base alloys containing MM, MM plus manganese, and MM plus zirconium.

Jan 1, 1985

By G. R. Fitterer

In the manufacture of steel by any process the refining period involves the partial elimination of the metalloids carbon, manganese, phosphorus, and silicon, by virtue of their reactions with ferrous oxide. At the end of this refining stage the metal consists chiefly of iron in which small amounts of these materials are dissolved. Unless some deoxidizer is added to the steel at this time, the reaction between carbon and ferrous oxide will continue with such force that it is impossible to form sound steel in the ingot molds. Instead, the product will exhibit a marked porosity due to the formation and trapping of carbon monoxide-the product of the reaction mentioned. However, if deoxidizers are added, steel may be obtained which is dense and free from gas bubbles. At the same time the deoxidation products will remain in the steel as impurities. For example, silicon additions form SiO2 or combinations of SiO2 and FeO. Additions of manganese form deoxidation products consisting of various proportions of MnO and FeO. It is also quite obvious that simultaneous additions of manganese and silicon will form oxide combinations either in the binary system MnO-SiO2 or in the ternary system FeO-MnO-SiO2. Work at the Pittsburgh Experiment Station of the United States Bureau of Mines, in cooperation with the Carnegie Institute of Technology and the Metallurgical Advisory Board, involved the study of such deoxidizing reactions and their products. In this connection considerable information is necessary concerning FeO, MnO, SiO2, and Al2O3, and their various combinations. Some of the most needed data are the melting points of all of these materials. At the outset of this work ordinary methods of melting point determinations were found to be inadequate for various reasons, and the procedure finally selected involved the use of the micropyrometer with occasional corroboration by quenching methods. The reasons for this selection, together with a description of the apparatus, are given in the following pages.

Jan 1, 1932

By Matthew N. Plis

This U.S. Bureau of Mines report presents the documentation for COALVAL, a coal property evaluation software package developed on Lotus 1-2-3,4 version 2.2, spreadsheets. The software is compatible with version 3.1 as well, and may provisionally be run on the earlier 2.01 version. COALVAL is a menu-driven program that produces a prefeasibility-level cost analysis of mine-planned coal resources. The package contains cost models for each of five coal mining methods commonly employed in Appalachia: auger, contour strip, mountain top removal, continuous miner, and longwall. Other models, such as a dragline cost model, will be incorporated as the Bureau's Coal Recoverability Program matures. COALVAL allows mine operators, evaluators, consultants, and Government entities to input resource data and the various production, operating, and cost variables that pertain to their property. The program can evaluate up to 25 seams, each to be mined with up to five different mining methods, within a given area. Summary spreadsheets listing the cost per clean ton to mine the resources, f.o.b. the tipple, are produced for each property, seam, and mining method/seam combination.

Jan 1, 1993

By E. C. Tarpley, H. M. Cooper, R. F. Abernethy

"INTRODUCTION The determination of moisture in coal is an empirical test, because the time, temperature, and equipment are specified. The essential features of the equipment, and details of the procedure are given in A.S.T.M. Designation: D271-44 5/. According to the specifications, the following features should be incorporated in the equipment used:1. Oven must have uniform temperature in all parts.2. Oven must be constructed with minimum of air space.3. Oven must have means of changing the air two to four times per minute.4. Air must be dried over sulfuric acid (sp. gr. 1.84).The analytical procedures governing most of the nation's coal purchases are those given in A.S.T.M. Standards referred to above. These standards are general and of such scope as to cover all ranks and types of coal. In cases where only the moisture is required, a faster method than the standard procedure is desired.The semi-automatic moisture tester manufactured by the Brabender Corp. has proved itself in many industrial processes where the rapid estimation of moisture is of vital importance. With the approval of A. C. Fieldner, chairman, A.S.T.M. Committee D-5, and through the courtesy of Lowell Malan, chief chemist, United Electric Coal Companies, who loaned the tester, tests were made to determine the feasibility of using this instrument to determine the moisture in coal."

Jun 1, 1948

By Douglas W. Fuerstenau

This report presents the results of an investigation of comminution in tumbling mills. Five different topics involved with ball mill and rod mill grinding kinetics were studied and the results analyzed in terms of phenomenological size reduction and transport models. Continuous rod mill grinding was found to be characterized by high Peclet numbers which permit simulation to be carried out by several methods. The dry batch ball mill grinding of mineral mixtures showed that the breakage rates of the components were composition-dependent but time-independent and were normalizable with specific energy. Locked-cycle tests on mineral mixtures showed that a grinding circuit may take a long time to attain steady-state, during which time the composition of the mill holdings, and hence the breakage rates of the components, continuously changed. This study revealed that under plant conditions, grinding circuits can be in transience perpetually. The transport of mineral mixtures through drums was found to exhibit complex size and/or density-dependent segregation. However, the grinding media in a ball mill can eliminate such segregation, thereby simplifying the modeling of the continuous grinding of complex feeds. Wet batch rod mill grinding on single minerals divulged that the normalizability of breakage kinetics is valid for slurries of constant pulp density at different hold-ups but cannot be extended to slurries varying in pulp density.

Jan 1, 1983

By R. S. Warfield

The Kasna Creek copper deposit near Lake Kontrashibuna in the Lake Clark region, Alaska, was the object of an investigative project by the Bureau of Mines during the fall of 1948. Recessed because of inclement weather, it was completed in 1949. This project was a part of the Bureau of Mines program in Alaska for the development of critical and strategic minerals. The ore bodies are contact-replacement deposits in limestone. Mineralization is mainly specular and micaceous hematite associated with chalcopyrite, calcite, chlorite, quartz, and amphibole. The deposit, on the right limit of Kasna Creek approximately 2 miles from the shore of Lake Kontrashibuna, is composed of two mineralized zones that range in altitude from 2,350 to 2,650 feet. This report contains a brief history of the prospect, description of the physical setting of the property, its geology, and the factual results of the Work performed by the Bureau of Mines.

Jan 1, 1951

By A. J. Kraemer

This paper is the second and concluding report of the results of the twenty-fourth semiannual survey made by the Bureau of Mines of motor gasoline marketed in the United states. The first report on this 1931 survey gave the results of the examination of the gasoline samples in accordance with the new Federal specification for United States Government Motor Gasoline. The present paper reports results of the examination of the gasolines for color, doctor test gravity, end point, per cent recovered copper-dish gum, and steam-oven gum. The retail price and the tax at the time each sample was taken are also reported.

Jan 1, 1932

By J. Patrick Ryan, Thor H. Kiilsgaard, Charles W. Merrill, E. T. McKnight

The U.S. Treasury stocks of silver have been reduced at such a rapid rate to meet industrial and coinage requirements that they face exhaustion in 3 or 4 years. Alleviation of the silver problem will require increasing supply or reduc ing demand. This paper examines poss ible long-range resource development and research programs and improved secondary recovery. The possible reduction or elimination of silver in coinage and development and introduction of substitutes in the arts and industry are also discussed.

Feb 1, 1965

By D. E. Andrus

This paper, which describes the milling practice at the Montana mine concentrator of the Eagle-Picher Lead Co., is one of a series being prepared by the United Slates Bureau of Mines. LOCATION The Montana mine is situated on the eastern edge of the Oro Blanco mountains at an elevation of 4,300 feet. It is in the Oro Blanco mining district, Santa Cruz County, in the southern part of Arizona, about 4 miles north of the Mexican border, 30 miles northwest of Nogales and 80 miles southwest of Tucson. Amado, a station on the Southern Pacific Railroad, midway between Tucson and Nogales, and about 40 miles northeast of the mine, is the shipping point and is reached over an excellent highway.

Jan 1, 1931

By M. H. Chetrick

Since 1945, a commercial-scale pilot plant for the gasification of lignite has been operated by the Bureau of Mines at Grand Forks, N. Dak. The description, operation, and objectives of this pilot plant have already been described in previous reports (6, 7, 8). Although the experimental data obtained from the operation of the externally heated retort have been tabulated and summarized (1, 7), few studies have been made in the correlation of these data. The purpose of the present investigation was to review the data taken in tests of the lignite-gasification pilot plant and to correlate the gas-composition data in terms of their basic factors.

Jan 1, 1950

By Edward D. Thimons

Because of the high number of accidental methane gas ignitions in metal and nonmetal mines, the Bureau of Mines searched for a simple guideline that would allow mine personnel to evaluate the methane hazard in a given mine. Air samples were collected by the Bureau in 53 metal and nonmetal mines and analyzed for trace evidence of methane gas. Samples were collected in the returns and at the working faces. Those mines classified as gassy by the Mine Safety and Health Administration had a significantly higher average methane concentration than those classified as nongassy. Of the 9 gassy mines sampled, 7 had methane concentrations above 100 ppm, whereas only 1 of the 44 nongassy mines had a concentration above 100 ppm. The 100-ppm concentration may be used as a simple and convenient guideline for forecasting the methane hazard in a mine, whether or not the mine is classified as gassy. There was no consistent correlation between commodity mined and methane concentration, nor was there a correlation between mine depth and methane concentration. Neither of these factors can be considered a guideline for predicting methane hazards.

Jan 1, 1979

By D. Harrington, C. W. Owings

The mining industry is gradually realizing that safety education and safety inspection are economic factors that may not be overlooked as a means of reducing operating costs . Many mine operators , however , have failed to realize the benefits of safety , and the efforts of the more progressive mining companies are offset by the carelessness of neighboring companies when the accident records of a community or a State or the nation as a whole are considered . This tendency is indicated by the data collected by the safety division of the United States Bureau of Mines . During the fiscal year ended June 30, 1930 , relatively definite information: was secureä concerning 34 mine explosions , 24 mine fires , and 29 miscellaneous accidents ; these accidents are by no means all of the explosions , fires , and miscellaneous accidents which occurred in the mines of the United States during the period; but the data on the fires and explosions constitute a record of all of those types of accidents that were called specifically to the attention of the safety division , and the miscellaneous accidents include those on which definite , detailed data were obtained by the safety division .

Jan 1, 1931

By A. M. Cummings

Each mining district presents different problems as to the methods of ore extraction cad underground support, which are dependent upon the type of the ore deposit and the character of the inclosing rock. Mining costs, however, depend largely aeon the efficiency with which the methods employed underground are [applie] as well as upon the selection of the method best adapted to the physical conditions. The purpose of this paper is to present to the operator in other districts a detailed description of ho mining method used ins results obtained in tie exploitation of the bedded magnetite deposits of the Mineville district. The town of Mineville is situated in the Adirondacks, five miles west of Port Henry on Lake Champlain.

Jan 1, 1928

By John J. Mulligan

The creeks draining Cape Mountain, on the western tip of Seward Peninsula, Alaska, comprise the Cape Mountain tin-placer district. Because of the war-caused shortage of tin, the Bureau of Mines in 1943 conducted a churn-drill placer reconnaissance to explore the district. Favorable indications were found, and plans were made for further investigation of the deposits; the plans were abandoned when tin again became plentiful. In July 1951 the Zenda Gold Mining Co. was granted a Defense Minerals Administration (Defense Minerals Exploration Administration after October 1951) loan to continue exploration of the more favorable areas indicated by results of the Bureau's investigation. Equipment was moved to the area in the fall and winter of 1951-52. During the 1952 field season, 209 churn-drill holes totaling 7,521 linear feet and 10 test shafts totaling 96 linear feet were sunk on the Cape Creek drainage. Work was resumed in 1953, when 56 churn-drill holes totaling 3,157 linear feet were drilled on Boulder Creek. The company planned to drill Goodwin Gulch and Goodwin Creek, but no further work was done owing to lack of capital.

Jan 1, 1959

By D. E. Wolfson

This report presents 900° C BM-AGA carbonization and related data for coals from the principal beds of Nicholas, Randolph, and Webster Counties, W. Va. Thirty-three samples from nine coal beds in three counties were car-bonized at 900° C in the l8-inch-diameter BM-AGA retort, data from which have been correlated with industrial production. Host of the samples were chemically suitable for metallurgical use, and their coking properties were satisfactory. Except for four of the Lower Kit-tanning samples, the ranges of constituents in the coal seams were 1.8 to 9.0 percent ash and 0.4 to 1.1 percent sulfur, values within the range of accept-ability for metallurgical coals. Coke strength indexes were normal for Appalachian coals of similar rank, and the tumbler stability indexes of the coke ranged from 35 to 57.

Jan 1, 1969

By E. A. Loria

High-quality sheet of electrowon molybdenum was attained by a sequence of procedure on pressed and arc-melted crystalline powders. The procedures included high-temperature, high-vacuum sintering treatments and the use of metal deoxidizers instead of carbon to improve the mechanical properties of the molybdenum sheet. Rolled sheet 60 mils thick was evaluated by tensile and bend tests, hardness measurements, microstructures, and recrystallization treatments. After stress relieving, yield strength ranged from 85,000 to 110,500 psi (0.2- percent offset) and ultimate strength ranged from 87,200 to 117,250 psi with 4.5- to 25-percent elongation observed for arc-melted sheet, and 5.0- to 23- percent elongation observed for powder metallurgy sheet. In room temperature bend tests the sheet yielded plastically, indicating that the ductile-brittle transition point was below room temperature. The diamond pyramid hardness (DPH) of the molybdenum sheet changed from 214 to 293 DPH for the stress-relieved condition to 177 to 185 DPH for the fully recrystallized condition. The brittleness of recrystallized molybdenum, reported by other investigators as characteristic of sheet prepared from commercial-grade hydrogen-reduced powders, was not in evidence. Recrystallized tensile specimens pulled at room temperature had an average elongation of 31 percent.

Jan 1, 1966

By C. J. Wilhelm

Brine produced from subsurface formations may be employed successfully instead of fresh water as a flooding, medium in the secondary recovery of oil. The feasibility of this substitution has been proved in the shallow "shoestring" area of eastern Kansas and northeastern Oklahoma, where the supply of fresh water often is limited. In this procedure all brine produced with the oil is returned to the formation and thus is prevented from contaminating streams and fresh-water supplies. This report includes a detailed description of a "flood project" in eastern Kansas studied by the Bureau of Mines. In an attempt to determine whether brine, when handled properly, can be used as effectively as fresh water in flooding oil from partly depleted, formations, an analysis was made of all .own conditions that influence flooding.

Jan 1, 1941