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By W. B. Berwald, T. W. Johnson

"The United States Bureau of Mines, in cooperation with the Natural Gas Department of the American Gas Association, has been studying actively for the past several years the flow of natural as through high-pressure pipe lines. 4 This report deals with that part of the study involving the design of pipe-line systems consisting of lines laid parallel to each other. The lines are referred to as the original line and the parallel line. The paralleling lire may or may not extend the entire length &f the original line; however, the parallel line is connected at its two ends to the original line.As a result of the large expansion of the natural-gas industry almost all markets within economic distance, from the developed as fields have at least one pipe line supplying them with natural gas. Small increases in the consumers' demand for natural-gas can be met usually by increasing operating pressures, but any marked increase in demand necessitates paralleling sections of the existing systems. It is believed that to a large extent future expansion in the natural—gas industry will consist of paralleling the present lines. The several formulas given in this report have been developed to aid in the design of such systems. Curves and tables were prepared from these formulas to simplify the calculations materially and to facilitate determination of the sizes of pine to be used in paralleling various diameter lines to give the most economical design. The formulas are presented without detailed derivations, as a complete report on the flow of natural gas through pipe lines is being prepared which will contain the derivations of these formulas. Examples included here show the detail of application of the several formulas to problems of design of parallel lines."

Jun 1, 1934

By L. G. Marshall

The geology, mining, beneficiating, types of products, and costs in terms of percent of total costs and of labor, power, and supplies of two crushed- limestone operations in Madison County, Iowa, are described in this paper. The operations are basically similar, differing in refinements in mining, product types, and markets. The operations are comparable as to personnel and as to weighted costs in terms of percent of total costs and in terms of man-hours, power, and supplies. The waste-to-stone stripping ratio is 1 to 0.8 at both operations, the powder factor is 0.29 pound of explosives per ton of stone, and daily production is 95 tons per man-shift. Both companies use crawler-mounted diesel shovels for loading, truck transportation, wagon drills, and dry screening.

Jan 1, 1963

By Rudolf E. Greuer, Linneas W. Laage, Xinton Chang

INPUT FORMAT INSTRUCTION FILE FOR PROGRAM MFIRE GENERAL RULES FOR DATA INPUT: $THERE IS NO NEED TO DISTINGUISH INTERGER AND REAL NUMBERS. $ $ SYMBOLS FOR NUMERICAL INPUT INCLUDE THE FOLLOWING $ $ 1234567890 -+BLANK $ $ * FREE FORMAT IS ALLOWED. COMMA AND BLANK SPACE CAN BOTH BE $ $ DELIMITERS. SEQUENTIALLY DISTRIBUTED BLANK SPACES ACT AS ONE $ $ DELIMITER. BLANKS ADJACENT TO A COMMA HAVE NO DELIMITING EFFECT $ $ * A ZERO INPUT CAN BE OMITTED BUT NOT THE DELIMITERS EXCEPT WHEN $ $ THE ZERO INPUTS ARE THE LAST ONES ON A LINE. $ $ * A LINE WHOSE FIRST NON-BLANK SYMBOL IS "$ IS AN INSTRUCTION $ $ LINE WHICH WILL BE IGNORED IN A PROGRAM RUN. $ $ * A LINE WHOSE FIRST NON-BLANK SYMBOL IS NEITHER ONE USED IN THE $ $ ABOVE LIST FOR NUMERICAL INPUT NOR "$, OR WHICH CONTAINS MORE $ $ THAN 3 SYMBOLS OUTSIDE OF THE LIST, IS A COMMENT LINE WHICH WILL $ $ BE SHOWN IN THE OUTPUT FILE. $

Jan 1, 1990

By L. A. Neumeier

Sound experimental ingots of zinc alloys for use as rolling slabs were cast with a specially constructed, semicontinuous casting machine. Nominal alloy compositions of Zn-1.0 percent Cu, Zn-0.12 and 0.36 percent Ti, and Zn-1.0 percent Cu-0.03 to 0.36 percent Ti were cast. This Bureau of Mines study was conducted to evaluate the suitability of the casting procedure for providing stock for rolling into sheet. Microscopic examination of ingot sections revealed structures in which grain size varied from the outer to center ingot zones. Columnar grains present in the center zone of the Zn-1.0 percent Cu ingot were absent in the titanium-containing ingots. The ingots with titanium displayed a finer grain size and eutectic structure in the center ingot zone than in the outer zone; the transition in grain size between the two zones was quite abrupt in some ingots. The overall grain size of the titanium-containing ingots was finer than that of alloys cast by more conventional methods. Chemical analysis revealed that compositional segregation is not a significant factor in the formation of the ingot structure. Microstructural studies of small ingots of similar alloys solidified at slow, fast, and intermediate rates confirmed that the ingot structure in the semicontinuous-cast ingots is related to cooling rate, which is, in turn, related to the particular casting machine design and the influx of cooling water on the withdrawing ingots. Microstructures of thin sheet hot-rolled from slabs of the semicontinuous-cast ingots demonstrated that the ingot structure does not preclude the rolling of sheet having a uniform microstructure. Results of hardness surveys of the semicontinuous-cast ingots demonstrated that copper and titanium exert essentially additive hardening effects in these cast alloys.

Jan 1, 1968

By R. E. Mussler

Electrowinning of copper from chloride solutions in a diaphragm cell was studied by the Bureau of Mines. The copper powder product was shaken periodically from the cathode and removed from the bottom of the cell. The effects of copper concentration, brine concentration, copper chloride species, and cell voltage were investigated. Power consumption of 1.1 and 2.1 kW-hr/kg were obtained with cuprous and cupric chloride solutions, respectively.

Jan 1, 1975

By Harry W. Campbell

A mineral survey by Bureau of Mines personnel identified no mineral resources or mineral occurrences with development potential at prospects in the Mecca Hills Wilderness Study Area (WSA). Bentonite occurrences are in Skeleton Canyon and Surprise Canyon. Sand and gravel occurrences are numerous in and near the WSA. Much of the Mecca Hills WSA was leased for oil and gas exploration in 1983. No current mining claims or other leases were found in the study area. The Skeleton Canyon Clay Mine yielded clay to seal irrigation canals, Clay to seal ponds was also mined from the Red Top Clay Mine west of the USA. A sand and gravel pit south of the study area (near Box Canyon Wash) supplied material for local construction projects. A commercial sand and gravel pit was operating in 1983 near the mouth of Thermal Canyon 4 miles west of the WSA.

Jan 1, 1984

By T. G. Carnahan

The Bureau of Mines conducted laboratory-scale weathering research on a leach residue containing elemental sulfur and mixed metal sulfides. Experiments were performed to determine pH and impurity element concentrations in the effluents as functions of time and to determine the effects on effluent concentrations of mixing the residue with dolomite tailing material. Four 800-day tests were conducted simultaneously. Soluble metal concentrations, especially zinc and copper, were excessive in the effluents from washed and unwashed samples of the residue. Concentrations of up to 20 g/l of Zn and 12 g/l of Cu were obtained. The pH values of the unwashed and washed residue effluents at the completion of the experiments were 2.8 and 1.9, respectively. Sulfuric acid from oxidation of pyrite caused the pH decrease. Mixing unwashed residue with dolomite tailing to maintain a near-neutral pH minimized the heavy metals content in the effluents. The pH in the dolomite tests increased slowly after the first 360 days and attained values of 7.8 and 8.2, respectively, for tailing containing 1 pct leach residue and for tailing devoid of leach residue. Dissolved zinc and copper did not exceed 0.10 g/l of Zn and 0.001 g/l of Cu.

Jan 1, 1982

By J. J. Forbes

The Act of Congress authorizing the establishment of the United States Bureau of Mines became effective July 1, 1910. One of the most important duties Congress delegated to the Bureau in this Act was the study of health and safety conditions in the mineral industries. Early investigations of these conditions revealed the need of prompt Care of injured employees, as, under the difficulties inherent in their occupation, seemingly unimportant wounds if not treated promptly might become infected and cause permanent disability or even death. Many seriously injured persons brought out of mines and plants by fellow workers ignorant of approved methods of giving first aid or of safe means of transportation have been caused suffering and have had injuries accentuated to such a degree as to bring about permanent disability or death. The need of general instruction in first aid thus became apparent. BRIEF HISTORY OF FIRST-AID WORK The education of miners in the United States in first aid probably was conducted systematically first by the anthracite industry in Pennsylvania. Subsequently, first-aid training was carried on actively in Alabama and Indiana. Meanwhile, a general training campaign was carried on among industrial workers by the American Red Cross Society; when the Bureau of Mines began its nation-wide campaign of instructing employees of the mineral industries, the Red Cross turned over that part of its industrial training work to the Bureau but continued to cooperate by furnishing surgeons as judges in important first-aid contests and demonstr tions and assisted for a number of years in determining training methods.

Jan 1, 1937

1. In 2002, a total of 256 metal mining operations reported employment to the Mine Safety and Health Administration (MSHA). Metal mines were the smallest mining sector,1 comprising 1.8% of all mining operations. • Gold mines comprised 44.1% (n = 113) of all metal mining operations. Other types of metal mines were copper ore (n = 31; 12.1%), iron ore (n = 25; 9.8%), and lead and/or zinc ore (n = 21; 8.2%). • Nevada is the state with the largest number of metal mines (n = 53; 20.7%).

Jan 1, 2004

By Irving Hartmann

Following the severe starch-dust explosion in the casting department of a large candy factory nearly 2 years ago, great interest has been shown in the explosive properties and the safe manufacture and handling of powdered starches. Under the auspices of the National Fire Protection Association, a committee has been formed to prepare a code aimed at preventing dust explosions in the confectionery industry. One objective of this code will be to reduce the explosion hazards of starches that are widely used for molding, dusting, and other candy-manufacturing processes. The explosibilities of starches and starch mixtures have been studied in the laboratories of the Bureau of Mines and elsewhere. The results of the initial experiments made by the Bureau on 10 samples of cornstarch and mixtures of cornstarch with other materials have been published. In response to numerous requests for additional information, further laboratory studies have been conducted. Data have been obtained on the effects of dust concentration, particle size, moisture content, admixture of .calcium carbonate, and on the effect of oil treatment on the explosibility of cornstarch. The results of this investigation are summarized in this report.

Jan 1, 1950

By C. Lorimar Colburn

"The use of helmets during the war has accentuated interest in the advisability of using stiff hats in mines to protect the miners against falling rocks. About forty per cent of the accidents in mines are due to falling rocks or roof. A large number of these accidents could be prevented if the miners wore stiff hats or helmets.The use of head protective devices in minas is not new, for they have been in use for many years in Europe and in the Lake Superior District in the United States. In practically all of the mining districts in Europe stiff hats of some kind are required by the mine management. George S. Rice, chief mining engineer of the Bureau of Mines, reported that in Germany, Belgium, and France stiff hats made of papier mache or felt rosin are in use. Similar hats are generally employed in the Lake Superior District. In building the subways of New York and Philadelphia it was the practice of engineers and workers to let the hair grow very long and to wear a close fitting cap or felt hat. In Germany the hats are high like the military helmets, whereas in France and Belgium they fit more closely to the crown. In England the practice is mixed. As a rule the miners use soft padded caps, but in Yorkshire many of the miners use sole leather, tight-fitting caps of jockey pattern with the seam forting a little ridge down the middle of the cap. These hats are very useful allow thin beds of coal, as in crawling one is very likely to strike his head a sharp piece of rock or on a timber. Of course, such mishaps are more likely to occur to a man not familiar with the mine. It must be admitted such hats do not stick on well, though this is usually due to their not being especially fitted. The German hat is particularly unsuited to an American-shaped head.It is interesting to note that on the continent tight cotton caps are generally worn over the hair and under the hard hat. This is a measure for cleanliness which is excellent. In low beds of coal share much crawling on hands and knees is necessary the dirt and coal dust sift down, making the miner black and dirty. In metal mines stiff hats are of especial use in shaft work; also in raises or high stapes. A small fragment of rock falling some distance either down a shaft or raise would kill a man if it struck him squarely on the head. A stiff hat or helmet may protect him and save his life. At a station in a shaft where men are loading the cage or skip, some kind of adequate head protector should be compulsory. A head-protecting hat or cup which is also a good insulator should be worn where there is danger of striking one's head against a wire carving an electric current."

Jun 1, 1920

By Murray Weintraub

The Bureau of Mines investigated the aerodynamic factors that control the functioning of the blowcase devices used in pneumatic processes for dispersing solids. Alumina powder of 8-micron mass-mean diameter was placed in 0.75- inch-diameter by 10-inch-long cylinders} and a blowcase technique was employed. It was determined that dimensions and gas rates for discharging the powder from the cylinder by a stream of gas may be calculated by assuming a fluidization mechanism and extrapolating residues to a desired finite quantity or to zero at the terminal velocity. The state of agglomeration of a powder at discharge may be determined from measurements of the velocity required for zero residue.

Jan 1, 1967

By F. B. Tough

"INTRODUCTION Organizations formed for the purpose of conducting conservation work in oil fields, in order to conserve and prolong the supply of crude petroleum are rare and novel. Such an organization is the Rocky Mountain Petroleum Association, Denver, Colo, As our production of petroleum can no longer keep with the consumption, the plan of organization, character of work, and results obtained by this association are well worth considering. It is hoped that the results achieved in the Wyoming fields will serve to stimulate similar organizations among operators in the state or other oil fields of the United States, The Rocky Mountain Petroleum Association, Danvers Colo., was formed in May, 1919. It comprises the Midwest Refining Co,. The Ohio Oil Co., and the Continental Oil Co. These three companies entered into a cooperative agree¬ment with the Federal Bureau of Mines whereby $30,000 would be spent under the direction of the bureau, which agreed to furnish competent men, and to furnish the work and expenditure of funds. Although the financial burden for the first year's work, now drawing o a close, was carried by only three companies, they stipulated their desire that the benefit of the work should accrue to the industry, and that the personnel employed should be as zealous to assist one operator as another, without regard to whether ha was contributing to the support of the work or not."

Apr 1, 1920

By Edward Thomas

In 1947 the Bureau of Mines, as an accident-prevention measure, decided to advocate the adoption of roof bolting (suspension roof supports) in coal mines where it appeared to be applicable. Subsequent experience has disclosed that the applicability of this support is more general than was first suspected; moreover, comparison of the accident records of mines before and after adoption of the roof-bolting method shows results that more than justify the effort and funds expended. The industry has responded enthusiastically, because roof bolting proved to be not only an accident-prevention measure but also one to increase productive efficiency. In some instances this increase in the productivity of men and machines has been almost incredible and has led many mining men to conclude that through some hocus-pocus they can now cast aside many or all of the time-proven rule of good mining practice. If this tendency is not counteracted, it could easily result in an increase of roof-fall accidents, which may outweigh the benefits of roof bolting and discredit an innovation in roof control that shows great promise of materially reducing our mining accidents. From an economic standpoint it may represent the margin between profit and loss in many mining operations. The purpose of this manuscript is not to propose an inflexible code or set of rules but to summarize the experience to date as a guide for those who have the responsibility for the installation and inspection of roof bolts. This experience consists of approximately 250 investigations of roof failure in which roof bolting was involved either directly or indirectly. It should be pointed out that many of these failures were controlled, occurring during experimental periods, and comparatively few of the accidental failures actually resulted in personal injury, yet a significant number represented potential hazards.

Jan 1, 1951

By Edward D. Thimons

A remote-actuated stench gas fire-warning system has been designed and tested by the Bureau of Mines. This system makes use of the hard-wire network for the mine's phone pager system, thus greatly reducing the system cost. By locating stench gas canisters with remote-actuation release capabilities near working sections, the fire-warning time can be greatly reduced. In a test of the system in a Missouri lead mine, the time required to warn miners of a fire at two working faces was reduced from about 20min with the conventional system to less than 4 min with the remote-actuated system.

Jan 1, 1984

By A. Gene Collins

Some of the geochemical relationships that exist between subsurface fluids and the associated geologic strata in petroleum producing areas of Louisiana have been determined. Samples of petroleum-associated water were obtained from 126 wells in Louisiana that produced from sediments of three geologic ages: Tertiary, Cretaceous, and Jurassic. The samples were trans-ported to a central laboratory for analysis of chemical composition, using standard methods, to determine if the compositions varied with the geologic strata of their source and, if so, why. The dissolved constituents were com-pared with those of a brine that was concentrated by evaporation. The concentrations of bromide, calcium, and strontium were useful in distinguishing the brines produced from sediments of a late age from those of an earlier age. The concentration ratios of Mg' (total equivalent magnesium) and bromide indicated that dolomitization probably had occurred and altered the composition of the brines. A principal-components analysis of the data indicated an inverse relationship between depth and concentrations of bromide, strontium, calcium, and lithium.

Jan 1, 1970

By Wm. W. Odell

A study of certain gas making and fuel problems peculiar to the gas industry of California has been made by the Bureau of Mines. The work was done at the request of, and in cooperation with The California Gas Research Council 2, for the purpose of obtaining basic information on the gas-making fuels available to California, and their applicability to the present and future needs of the gas industry in that State. The data obtained have been applied in outlining a construction program, and indicate the possibilities in efficiently utilizing fuels in making gas by other than the oil-gas process. This paper presents an outline of the study and a summary of the principal results obtained, with some of the more important conclusions and recommendations based on this data. Gas is produced in California by processes which are both unique and different from those common to other parts of the United States. The bulk of the manufactured gas is made in and distributed from two main districts which are centers of population - namely, the Los Angeles district and the San Francisco Bay district. The gas manufactured in the Bay district is, almost exclusively oil-gas, whereas that produced in the southern part of the State, where natural gas is available, is mostly mixed natural gas and reformed-gas, but oil-gas is the chief product when the supply of natural gas is inadequate. Practically all of the gas companies are equipped with oil-gas generating apparatus, and anticipate using it in the future. As the continued use of the oil-gas process to the exclusion of all other processes, depends upon a continued supply of oil at a low cost, and the prospect of obtaining such low-priced oil in the future is somewhat uncertain, the questions have arisen: What will the future gas-making process or processes be? When will it be necessary to make plans for the installation of different gas generating equipment, and what will that equipment comprise?

Jan 1, 1926

By Philip A. Holland

The Bureau of Mines has developed a method for determining helium in water for use in sampling and analyzing surface and subsurface waters for geochemical survey work. The accuracy of the analytical method is within ±10 percent for samples containing above 20 x 10-8 cm3 He (STP)/cm3 H20. The minimum detectable helium-in-water concentration is calculated to be 2 x 10-8 cm3 He (STP)/cm3 water. Water samples are collected in 500-cm3 stainless steel cylinders. The dissolved gases are extracted into a cylinder of equal volume containing a known quantity of neon. The resulting gas mixture is subsequently analyzed for helium and neon-21 by mass spectrometry. The volume of helium in the sample is calculated from the mass spectrometric determination of the helium-to-neon-21 ratio, the known quantity of neon used, and the extraction efficiency of helium.

Jan 1, 1981

By Nicholas G. Theofilos

Ecuador's real gross domestic product (GDP) increased 6% in 1976 despite persistent shortages of electrical power and essential fuels, which caused factory slow-downs and shutdowns. Petroleum export earnings, which made up more than 50% of total export value in 19716, totaled $565 million, a 9% increase over those of 1975. A new 60,000-barrel-per-day oil refinery at Esmeraldas was scheduled to go on- stream in mid- 1 97 7, operating entirely on Ecuadorean crude. Corpración Estatal Petró1era Ecualtoriana (CEPE) started construction of a 600-kilometer network of product pipelines which was scheduled to be completed in 1977 to coincide with the completion of the refinery.

Jan 1, 1980

By A. J. Barry

Five makes of expansion-type shells and two types of bolts (mild-steel and high-strength) were used in 30 tests made in sandstone and shale roof, The results show that the anchorage obtained in both the sandstone and shale were stronger than either type of bolt. That is, the yield loads of both bolt types were exceeded before excessive anchor slip occurred. A relationship for evaluating the anchorage effectiveness of 3/8-inch-diameter, expansion-type bolts is presented. A comparison of test results indicates that the anchorage effectiveness of 5/8-inch- and 3/4-inch-diameter expansion-type bolts did not differ appreciably.

Jan 1, 1957