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By Charles W. Frey

SUCCESSFUL mining today means proper mechanization. Before any mine can begin production on a paying scale, some machinery must be installed. There must be pumps to remove water, fans and blowers to provide proper ventilation, elevators and hoists to raise materials, and a source of power to turn the countless wheels on which the world's mineral supply rolls from its earthhound source to the market. Only the prospector with his burro and the anthracite "bootlegger" continue to mine without mechanical aid, and with the recent years even these can be discounted, for the burro has given way to the Model T, and the "independent" coal miner must have a truck to haul his coal away. The few types of machinery mentioned above are but a beginning. The

Jan 1, 1938

By Charles W. Frey

COMPRESSED air is one of the most useful tools that the mine operator has at his disposal. It is clean, nontoxic, easily handled, and can be distributed anywhere that a man can drag a length of rubber hose. Without it a great deal of drilling would still be a laborious hand process, and although the John Henry of legendary fame could beat a mechanical drill, John Henrys are few and far between, and in the long run the air drill is the victor. As a general rule, horizontal compressors are lubricated by mechanical lubricators, which furnish oil to the cylinder walls, whereas vertical units are splash lubricated. In most horizontal machines oil is introduced at the top center of the piston, from which point it can run down and lubricate the rest of the piston. Some large units introduce oil at more than one point on the cylinder wall, the necessity for this and the number of points of introduction depending upon the size of the cylinder.

Jan 1, 1938

By Charles W. Frey

OF all the machinery used in mining work, mine cars are probably the most abused. They are hauled through water and muck, up hill and down grade, whipped around curves, bumped and jerked, and exposed to the ravages of the weather. However, as a general rule their lubrication is not altogether neglected. The mine operator may not heed the extra drag that a frozen conveyor bearing gives, but he is all too aware of the increased load that faulty mine car wheels put on his power plant. When the circuit breakers begin to fly, and when his mine loco- motives come out with only half the cars that they were able to carry a month before, then neglected mine car wheel lubrication becomes apparent, and woe to the person responsible.

Jan 1, 1938

By William T. Folwell

The Lucky Friday mine east of Mullan, Idaho, is an outstanding example of a property in the Coeur d’Alene district where a small and insignificant- appearing silver-lead-zinc vein at the surface has changed at depth into a large vein of great importance. The Lucky Friday vein has little if any surface expression and above the 1200 level the ore shoots are small and discontinuous. Between the 1200 level and 2450 level, the lowest developed level, the main ore shoot has shown remarkable improvement on each succeeding lower level, and today the mine is one of the major lead-silver producers in the Coeur d'Alene district. History: The Lucky Friday property is on the north side of the South Fork of the Coeur d'Alene River in sections 25, 26 and 35, T. 48 N., R. 5 E., Hunter mining district, Shoshone County, Idaho. This is about one mile east of the town of Mullan, which serves the eastern portion of the Coeur d'Alene district. The southern part of the property is crossed by a branch line of the Northern Pacific Ry. and by U. S. Highway 10. This highway is the principal road crossing the panhandle of Idaho and connects the district with Spokane, Wash., on the west and Missoula, Mont., on the east. The main portal and surface plant of the Lucky Friday mine is at an elevation of 3365 ft, only a short distance above the valley floor and a few hundred feet from U. S. Highway 10, so the mine is readily accessible for year-round operation.

Jan 12, 1958

By D. C. Anderson

Utah Construction & Mining Co.'s Lucky Mc mine is one of the major uranium producers in the United States. It is located near the geographic center of Wyoming in Fremont County. The climate is middle-latitude steppe, with an average annual precipitation amount of 10 in.; the temperature varies from 40º below zero to 100º above. The land surface is moundlike, rolling terrain, with sparse grass and sagebrush. The northern slopes of the higher ridges support a scattering of juniper and pi[n]ion growth. DISCOVERY The discovery was made by Neil E. McNeice, of Riverton, Wyo., on Sept. 13, 1953. After prospecting the area and staking a few claims, McNeice reported his findings to geologists of the Atomic Energy Commission (AEC), who immediately began preliminary studies of the numerous surface uranium exposures of the district. The discovery received widespread publicity, resulting in an intensive search for uranium throughout the region ; thousands of claims were staked. The AEC drilled several shallow holes near the discovery outcrop. Assays of cuttings from these holes confirmed the presence of a low-grade, oxidized uranium deposit. McNeice and his partner, L. A. Morfeld, tried to start a mining operation but were plagued by a lack of capital and technical know-how. They sought assistance from a Salt-Lake-City-based mining firm, the New Park Mining Co., engaged in underground base-metal mining in the Park City district of Utah. After a period of negotiations, New Park initiated activities that led to the forming of the original Lucky Mc Uranium Corp. The company started limited development drilling and mining operations in the summer of 1954, with the first ore production being shipped by truck to the Vitro mill in Salt Lake City. The mining

Jan 1, 1969

By Geo. W. Bain

PRODUCERS of building stone have had to seek new and attractive uses for their output to supplement the diminished orders for standard products. Lunar is the direct result of the need of new outlets for marble and is. probably the most ingenious and attractive type to reach the market in a quarter of a century. It is a highly translucent stone which retains the same glistening sparkle in transmitted light that marble exhibits by incident rays. This sparkle sets it apart entirely from translucencies made of glass or even onyx, alabaster, and the distinctive exceedingly fine textured calcite marbles produced in Alabama and quarried formerly in northern Vermont and Quebec.

Jan 1, 1936

By C. E. Barnett, G. R. Durland

LUMINESCENT materials have been used in an increasing variety of ways in recent years. Such uses range from the screens on which the picture or image is presented in television and other cathode ray tubes to fluorescent lamps, fluorescent effects in decorative, theatrical, and display lighting, and the many applications of phosphorescence in paints, textiles, paper, and plastics. During the war the screens for a radar set or the "night-seeing" devices were not fundamentally different from those in other cathode ray tubes, but nevertheless they presented special problems for the phosphor manufacturer. It was essential that the "pips" on a radar screen continue to glow after the exciting beam had swept on, but this afterglow would be ruinous to a television screen. In the image tube used for seeing at night with infrared instead of visible light, electrons emitted by an infrared-sensitive receiving surface were amplified and converted to visible light after striking a fluorescent screen. The small size of the screen caused special problems in reducing the grain size of the phosphor to obtain adequate resolution. Other devices used phosphor surfaces which could be stimulated directly by infrared radiation to emit visible light. Energy was stored in the phosphors by prior excitation with short-wave-length radiation, and the stored energy released on subsequent exposure to infrared radiation. Maps, navigational charts, bombing manuals, and computers of various sorts were printed on fluorescent paper or lettered with fluorescent inks. Fluorescent markings excited by small ultraviolet lamps were used on airplane instrument dials. A large amount of research was done to determine the best color for the emitted light and other properties for the fluorescent materials, and on the best methods for their fabrication into the items listed above. Phosphorescent materials found wide use during blackout restrictions to mark safe passageways, to delineate traffic hazards, to identify packages, and to mark tools and other items of equipment.

Jan 1, 1948

By R. W. Raymond

FOUR portraits have recently been hung in the rooms of the Institute, in recognition of four illustrious men with whom we, as mining engineers and metallurgists, may claim fellowship. LUTHER. Martin Luther is often spoken of as a miner's son; but it is less generally known that John Luther, his father, was, in a small way, a metallurgist as well as a miner, and that Martin Luther himself, in his youth, worked in a forge or bloomary established by his father at Mansfeld, Saxony. Since this is the only manual occupation on his part of which we have any record, it is fair to assume that the great scholar and reformer derived from his work in this department the practical familiarity with the conditions of human labor so abundantly evinced in the homely illustrations which accompany even his serious arguments, and in the witty apothegms of his famous "table-talk." At the same time, I must confess that 1 have not been able to find in any of the works of Luther distinct allusions to mining or metallurgy. KÖRNER. Theodor Körner, a student at the Mining Academy of Freiberg, Saxony, threw himself into the German War of Freedom in the first decade of the 19th Century. He was a poet of no mean rank ; and his " Song of the Sword " is one of the great lyrics of literature. This poem was written but a few days before he died in battle. In many respects, Körner may be compared with our American hero Theodore Winthrop, who similarly met a glorious fate, and left behind him prophetic indications of genius, of which his premature death prevented the complete fulfillment. I am informed by a member of the Institute that Körner's admirable collection of minerals is still preserved at Dresden.

Nov 1, 1908

By Howard Eavenson

EARLY in 1917, the United States Coal & Coke Co. secured options on several tracts in Harlan County, Ky., aggregating about 1.9,000 acres in area, and after careful prospecting by outcrop openings and diamond drilling, completed the purchase late in July of that year. This property is situated in the eastern end of Harlan County, south of the Poor Fork f Cumberland River, and extending across Big Black Mountain to the Clover Fork of Cumberland River, a distance of about 7 mi. (11.3 kg.). It extends from the Kentucky-Virginia line westward for about 6 mi. Looney Creek, which empties into Poor Fork, crosses the property for about 4 mi. (6.4 kg.), and as several of the seams within the property outcrop along this stream, it afforded an easy, and the logical, place for development. The property is on the northern side of the geological trough formed by the uplifting of Stone Mountain, on the southern, and Pine Mountain, on the northern side; the northern boundary along Poor Fork is practically at the base of Pine Mountain. This, area has been described in various geological reports.1 The main seam on this property is the one known variously as the "C," Benham, Keokee, Taggart, and Roda; it is, also called, by the Kentucky Geological Survey, the Kellioka seam of the western portion of Harlan County. This seam averages, in this property, about 5 ft. (1.5 m.) in thickness, although local rolls reduce this thickness considerably over small areas; and at the extreme western end of the property the seam splits. It is usually clean, although occasionally a small parting occurs within a few inches f the bottom f the seam; it is one f the best

Jan 9, 1921

By AIME AIME

M ALBERTSON is research engineer for the Shell Petroleum COT. He joined the Roxana Petroleum Corp. (later the Shell) in 1920, at Hanger, Texas, became district geologist at Shreveport, and after two years was transferred to the production department, where he has been for the past fifteen years. His jobs have ranged from a modest field engineer up to assistant production manager. During this time hc has successively resided in Texas, Louisiana, Missouri, Louisiana, Oklahoma, Missouri, Texas, The Hague (Holland), and Texas. II? the Yates Pool, Texas, in 1929, "Al" initiated' the tubing of wells under pressure to control gas-oil ratios, particularly at restricted rates of flow. This led to the compulsory tubing of all oil wells drilled in the State

Jan 1, 1937

By AIME AIME

EVER since his college days at the University of Iowa, the professional interest of Morris Morgan Leighton has centered on geology, and he now heads the State Geological Survey of Illinois. Just 52 years ago--on Aug. 4, 1887-he was born at Wellman, Iowa. He remained at the State university for his Master's degree, awarded in 1913. A two-year fellowship at the University of Chicago led to a Ph. D. degree, after which Dr. Leighton went out to Seattle as instructor in geology at the University of Washington during 1915-'16. He returned to Iowa as assistant professor of geology at Iowa State Teachers' College for a year, followed by another year at Seattle, after which he returned permanently to the Middle West, first as acting professor of geology at Ohio State and then, from 1919 to 1923, as assistant professor of geology at the University of Illinois and geologist for the Illinois Geological Survey. Of the latter organization he has been chief since 1923, with no present teaching duties. As a result of the successful work of the Survey, notably in non-metallics and in the initiation and stimulation of the recent oil activities in the southern part of the State, it is soon to have a new building with modern laboratory facilities.

Jan 1, 1939

By Alan Morris

BRASS rod for use in automatic screw machines is one of the major products of the brass mills. A large tonnage is consumed each year in the manufacture of an endless variety of finished articles and parts for assembly into other products. The machines that do this work have been developed to a high degree of efficiency, and their manufacturers are still striving for higher production speeds. This development has brought with it a demand for brass rod to meet the increasingly difficult machining conditions. This paper is a report of the results of tests undertaken in an effort to obtain a measure of the effects of such variables as lead content, microstructure and cold work on the machinability of brass rod. It is realized that the term "machinability" has never been well defined. Power, finish and tool life all should have a place in such a. definition. In practice it is sometimes found necessary to sacrifice some of these in order to obtain a rod that will not tend to throw up a burr, or will give a burr which is easily tumbled off. Again a specially stiff rod may be necessary because of long overhang from the chuck or a rod of special characteristics is needed to take a given broaching operation without chattering. It is only through an understanding of the effect of basic mill operations on the machinability of the rod that such problems as these may be solved most economically. It is hoped that this paper, together with the discussion it may evoke, will prove to be a basis for such an understanding.

Jan 1, 1932

By Alan Morris

IN a previous paper1 the results of cutting tests on free-cutting brass rod were reported. Investigation was made of the effects of variation in lead content, microstructure and cold drawing. The author's reply to the discussion of that paper includes a study of the directional cutting properties of drawn and annealed rod. The present paper records the results of tests made on series of samples in which the tin, iron and copper contents have been varied. The apparatus, used and method of testing are described in detail in the previous paper. The machine is of the pendulum-operated milling type used and described by Airey and Oxford.2 Angular readings of the height to which the pendulum rises after falling from a fixed position, both when a cut is made and when the pendulum swings freely, give the basis for calculation of the energy consumed in making a cut. Careful weighing of the sample before and after cutting gives a measure of the amount of metal removed. The results are expressed in foot-pounds per cubic inch of metal removed, and have been called "unit cutting energy." In the course of the discussion of the author's earlier paper, W. B. Price reported large-scale tests involving some 50,000 lb. of material. These tests indicated that the addition of as much as 0.6 per cent of iron and 0.25 per cent of tin had apparently no adverse effect on the high-speed cutting characteristics of the rod. The rod also contained a small amount of nickel. The test results reported here tend to confirm his observations.

Jan 1, 1933

By George Jones

MACHINE mining on the pitch plays an important part in the produc-tion schedule at the Salem Hill Colliery of the Haddock Mining Co. This mine is just outside the city of Pottsville, in Schuylkill County, along the southern border of the Anthracite Region. The entrance to the mine is through a cross-measure tunnel 15 ft. above water level and running north 1500 ft. until it strikes the Rabbit Hole vein, where the machine mining is carried on. The main slope, dipping south, was sunk 1200 ft. in the Rabbit Hole vein with levels turned off at 300-ft. intervals. The vein is from 24 to 30 in. thick on a varying pitch of 20° to 40°. The overburden has differed from 50 to 466 ft., the most recent work having the maximum overburden. Immediately over the Rabbit Hole vein is a seam of soft sand slate from 1 to 4 ft. thick which presents a problem at times because it dis-integrates rapidly when exposed to the air. It will crack up and fall without any audible warning, therefore the workmen must always be on the alert, watching for loose slabs. The main top is sandstone, vary-ing in thickness from 8 to 20 ft. The bottom rock is similar to the top, but is finer grained and subject to a more complete disintegration. The vein has a 3 to 4-in. shelly band along the bottom, and all under-cutting has been done in this soft band.

Jan 1, 1935

By J. Sajkiewicz

In a synthetic way discussed are certain results of papers realized at the Wroclaw Technical University in a field of the theory of exploitation of machine systems with conveyor-belt transport. The attention is paid to the two lines in these works which are concerned with the development of analytical as well as simulation methods, in both cases realized with the help of digilat computers.

Jan 1, 1977

By Henry H. Thomas

In Tasmania a tailrace tunnel to handle water discharged from a turbine generator has been successfully driven by a machine tunneling method similar to that described in the July 1962 issue of Civil Engineering. The Hydro-Electric Commission, Tasmania, is constructing a high- head (2750 ft) power project that will utilize the storage in the Great Lake (1,150,000 acre-ft) at an elevation of 3380 ft. The underground power station will house six vertical shaft turbo-generators, each rated at 50,000 kw. The tailrace tunnel, 16 ft diam and 14,600 ft long, was driven through a reasonably homogeneous hard mudstone. It was decided to excavate this mechanically in the hope of saving some money on excavation and a considerable sum on the ultimate lining of the tunnel. Mechanical engineers from Tasmania worked with the firm of James S. Robbins and Associates of Seattle, Wash., which designed and supplied the "mole."

Jan 4, 1963

By R. J. Robbins, D. L. Anderson

A tunnel boring machine has potential use in al- most any type of mining where the access shaft (or adit) is large enough or can be made large enough for its initial entry and where the orebody is of sufficient size to warrant its use. Some time will inevitably be lost in negotiating curves or making lateral moves and moving from level to level. Nevertheless, if the orebody is sufficiently large, advance scheduling can minimize the lost time encountered in such moves. Ideally, a mine will be planned for the use of these machines, thus eliminating access and transport problems. From the viewpoint of time involved, the rate of advance by boring as compared to conventional means is worthy of review. For instance, the Blanco Tunnel, one section of the Bureau of Reclamation's San Juan-Chama Project in southern Colorado, was bored in competent sedimentary rock with the following performance:

Jan 7, 1967

By S. J. Page

Introduction Dust from cutter machines and face drills is controlled in most mines by water. However, the large quantities of water used in metal and coal mines for dust control and suppression pose serious operational problems in water soluble ores, such as salt, trona, or gypsum. This paper reviews the strategies to suppress and collect dust on cutter machines and face drills where water usage must be restricted to very low flow rates - typically 3.78 L/min (1 gpm) or less.

Jan 1, 1985

By William G. Kegel

Aside from having a usable product and good mining conditions, the greatest asset for a profitable coal mining organization is an effective mine maintenance program. The first step in acquiring this is the presence of good mechanics-men who have a desire to be mechanics and who want to know more about the design and control of the machines in their charge. The knowledge and ability to be found in a good mechanic is the result of ambition, curiosity, and determination. With these qualities as a start, the aspiring mechanic can launch his career if he begins learning all he can about mechanics, electricity, and hydraulics. The path is rough, but the goal is rewarding. Mining machinery probably absorbs as much or more abuse than any other heavy equipment in use today. And when one considers the conditions under which much of the repair work must be done, it can be seen that the mine operator needs the best of men and tools to perform the service. MOTORS AND POWER SUPPLY Mining machines, from their inception, have utilized the electric motor; and down through the years of mechanization, this power source has undergone many changes to better adapt it to the job. The first motors used were large, heavy-framed, open d-c motors (direct current), using a series or shunt winding. A motor having one or more field coils connected in series and themselves in series with the armature, is called a series motor (Fig. 1). The series motor had the advantage of quickly developing starting torque, and it was, and still is, the best motor for locomotive or shuttle car tramming service. The series motor, however, speeds up as the load is reduced and, if not properly controlled, can overspeed. The shunt motor, as its name implies, has one or more field coils in

Jan 1, 1973

By William G. Kegel

Apart from a usable product and good mining conditions, the greatest asset for a profitable coal mining organization is an effective mine maintenance program. The first step in achieving this is to have good mechanics-or men who want to be mechanics and are interested in knowing ,more about the design and control of the machines in their charge. A good mechanic's knowledge and ability result from ambition, curiosity, and determination. Starting with these qualities, the aspiring mechanic can launch his career by learning all he can about mechanics, electricity, and hydraulics. Though the path is rough, the end result is rewarding. Mining machinery probably receives as much, if not more, abuse as any other heavy equipment in use today. Considering the conditions under which much of the repair work must be done, it is essential that the mine operator has the best men and tools to perform the work. Mining machines, from their inception, have utilized the electric motor ; and down through the years of mechanization, this power source has undergone many changes to better adapt it to the job. The first motors used were direct-current (d-c) motors since d-c power was the most economical power source for mining at the time of early mechanization. These motors were large open-type machines which are seldom used in modern mining. Because of the mine environment, the d-c motor has been reduced in size to better suit the application in mining machines and is now manufactured with dust-tight or explosion-proof enclosures. The d-c motor is constructed with either (or both) series and shunt fields located on the stationary part of the motor (stator) and an armature coil wound on the rotating part of the motor (rotor). Power is supplied to the armature by brushes which are held stationary and make sliding contact with the armature. The brushes requires regular and careful maintenance because worn or defective brushes will cause heat or arcing which can destroy the motor. D-c motors can be used as d-c generators when mechanical power is supplied to them by the rotating

Jan 1, 1981