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By P. J. Conners, H. Colijn

Belt conveyors have proven themselves for many years as a dependable and low cost method of moving bulk materials at high flow rates. The success of a belt conveyor system greatly depends on the initial loading of the material on the belt. If the material is loaded on the belt at the center, at the same speed and without impact, then about 90% of all belt conveyor problems would disappear. Proper belt loading is primarily determined by the engineering and design of the conveyor transfer point. Some general design criteria required for proper transfer of materials from one conveyor to another are established and discussed. Specific attention is given to loading chutes and skirting.

Jan 1, 1973

By William E. Bruce

This paper is intended to provide an improved understanding of natural draft (natural ventilating pressure) and the effect of natural draft on underground mine ventilation circuits. Attention is focused on measurement of natural draft pressures during ventilation surveys in mechanically ventilated mines and on different methods for modeling natural draft using the measured data. A number of examples are presented which utilize data collected during absolute air pressure surveys made by personnel of the Ventilation Division of the Mine Safety and Health Administration's Safety and Health Technology Center, Denver, Colorado. Examples are used to illustrate how the data from absolute air pressure surveys may be interpreted to determine whether natural draft pressure is present and what its magnitude is. In addition, two different methods are described for mathematically estimating the magnitude of the natural draft pressure. Comparisons are made of results obtained using the different methods. Different procedures are described for modeling natural draft using the MSHA-modified Penn State computer program. Use of the routines is described and illustrated relative to drafts that aid or oppose the mechanical ventilation system. Tabulations of results facilitate comparison of outcomes obtained using the different modeling procedures.

Jan 1, 1982

By W. B. Daly

THE sampling and estimating of, the orebodies in the mines of the Anaconda Copper Mining Co., at Butte, have been made a part of the work of the geological department. The wisdom of this assignment is apparent, considering the organization of that department, the nature of, its records, and the scope of its regular work. In the first place, the district is divided into units of two or three mines each and a geologist is assigned to each group. His trips to all the working places are frequent and he follows the mining operations closely. His notes are graphic and detailed. In the office, he posts his notes on the standard maps and sections and on special maps for correlation purposes. With the approval of the chief or assistant chief geologist, he recommends development work underground and watches its progress. This gives the geological department a precise knowledge of the character of each orebody. Sampling is done by one or two samplers at each mine working under a chief sampler stationed in the geological office. The chief sampler has access to all the office maps and is in frequent consultation with the geologists; his instructions to the samplers are issued with the approval of the chief or assistant chief geologist. Not only is it important that the geologic information be used to direct the sampling but the reports of the samplers and the records kept by their chief are useful to the geologist, who needs them in his work of I estimating ore reserves and deciding on recommendations for development work. The sampler, moreover, is at the mine every day and makes a daily report, which keeps the geologist in close touch with 'the progress of development work. The sampler is attached to the mine office and thus comes under the jurisdiction of the operating department. In fact, any special orders prepared by the chief sampler are submitted to the general superintendent, after approval by the geological department. The mine foreman may.

Jan 2, 1922

By L. C. Campbell

The purpose of any accident-prevention program is the curtailment or entire elimination of injuries and fatalities. It is a job that is never finished in the coal-mining industry. Day by day, on shift and off shift, men are exposed to injury and death in varying numbers. Seldom is it possible to lock up at the end of the shift and leave a mine plant in the care of a sleepy watchman, as can be done at most manufacturing plants. Even on off shifts there are maintenance and supply crews, coal cutters, pumpers and ventilation men exposed to danger. The prevention program of The Koppers Coal Co. recognizes two primary facts: First, no program can be successful without the full support of the management and complete knowledge of the job at hand on the part of every supervisor. Second, and equally important, is the full cooperation of every employee in observing the safety rules and practices set up by the management. Conscious day-to-day concern for his safety by the individual worker is the longest stride toward a good safety experience. How to accomplish the education of the individual worker and supervisor for safety is the problem of The Koppers Coal Co., as it is the problem of all coal companies. Safety Rules A simply stated set of Safety Rules and Practices for the government of employees is the starting point with The Koppers Coal Co. There are but 13 of these rules, which are short, easily understood and followed by a campaign of education and inspection. Each employee receives a set of these Safety Rules and Practices and signs a receipt for them, which is bound in at the back of the booklet, and this receipt becomes a part of his employment record. These rules and practices are as follows: Introduction The following rules have been compiled for the safety of employees and are established according to rules number one and number two of the official bulletin

Jan 1, 1940

By L. C. Campbell

The purpose of any accident-prevention program is the curtailment or entire elimination of injuries and fatalities. It is a job that is never finished in the coal-mining industry. Day by day, on shift and off shift, men are exposed to injury and death in varying numbers. Seldom is it possible to lock up at the end of the shift and leave a mine plant in the care of a sleepy watchman, as can be done at most manufacturing plants. Even on off shifts there are maintenance and supply crews, coal cutters, pumpers and ventilation men exposed to danger. The prevention program of The Koppers Coal Co. recognizes two primary facts: First, no program can be successful without the full support of the management and complete knowledge of the job at hand on the part of every supervisor. Second, and equally important, is the full cooperation of every employee in observing the safety rules and practices set up by the management. Conscious day-to-day concern for his safety by the individual worker is the longest stride toward a good safety experience. How to accomplish the education of the individual worker and supervisor for safety is the problem of The Koppers Coal Co., as it is the problem of all coal companies. Safety Rules A simply stated set of Safety Rules and Practices for the government of employees is the starting point with The Koppers Coal Co. There are but 13 of these rules, which are short, easily understood and followed by a campaign of education and inspection. Each employee receives a set of these Safety Rules and Practices and signs a receipt for them, which is bound in at the back of the booklet, and this receipt becomes a part of his employment record. These rules and practices are as follows: Introduction The following rules have been compiled for the safety of employees and are established according to rules number one and number two of the official bulletin

Jan 1, 1940

By William R. Webster

An investigation has been made of 500 samples of universal and sheared plates of basic Bessemer and basic open-hearth steel manufactured by the Pottstown Iron Company, the carbon-limits being 0.07 to 0.18 per cent. Through the courtesy of Mr. W. H. Morris, President, I am able to lag before the Institute the results of these tests. The samples tested were all taken from the finished material, and the chemical determinations were made on drillings from the broken test-pieces, which were sent to the chemist without giving him the heat-numbers. The results are such as to encourage me to keep on with the work, and, if possible, to have it carried out on other steels. It is kith this view that I now offer my tables in their incomplete form. My first table mas constructed by grouping the tests according to chemical analysis in various. ways, and making a rough tabulated statement, from which the ultimate strengths were worked out and carefully compared with the actual results of the tension-tests. From data thus obtained, one table after another was worked out, and by this method of "cutting and trying" I finally arrived at the results which I now present in Table I. (p. 771). I do not claim absolute accuracy, but my approximations have proved to be so close that the figures are practical data for current use at the works. The indications are that a pure iron, without carbon, phosphorus, manganese, or silicon, if it could be obtained, would give 38,000 pounds ultimate strength. This is assumed as a base, and to it is added the effect of each of the above elements, as explained below. The upper part of Table I. gives the ultimate strength due to carbon and phosphorus, and is the same for both basic Bessemer and basic open-hearth steels. The lower part gives the increase in ultimate strength due to manganese. By adding this to the amount obtained from the upper part, we have the ultimate strength of basic Bessemer

Jan 1, 1893

By Gustav Egloff

THE treatment of emulsified crude oils has been a problem for years in the petroleum industry. Until comparatively recently various methods of settling with and without chemicals have been used with indifferent success. Since wells have been acidized, emulsified crudes have been produced, which acid considerably to the need for improved methods of treatment. The presence of large quantities of salts in the oils from acid-ized wells has presented several new problems to the industry. The use of hydrochloric acid in well treatments has caused the formation of sodium, magnesium, and calcium chlorides by interaction with the dolomitic limestones. These salts dissolve readily in the water normally present in the oil, and they are therefore incorporated in the emulsified oil. The crystalline salts have also been found in the oil, prevented from settling by protective films such as asphalt, resins and petrolatum. In, some instances, free hydrochloric acid has been found. The salts may be present in crude oil in amounts ranging from a few pounds to over 1000 lb. per 1000 bbl. of oil. The transportation of these crude oils through pipe lines has led to erosive and corrosive effects, which are a tremendous cost to the petroleum industry. During 1937, more than 1,200,000,000 bbl. of crude oil was transported through pipe lines. Of this quantity approximately 10,000,000 bbl. was water, and considerably more than 50,000,000 lb. was salts. If the crude oils were treated at the producing wells to remove the salts and water, an appreciable saving would be possible. The treatment would not be difficult, since it has been found that these oils are more easily treated at the time they are produced than after the aging and more stable emulsification that occur before they reach the refinery. Since great costs are involved in the use of these salty crudes at the refinery, treated oils essentially free of salts would naturally command a premium.

Jan 1, 1938

By A. Eilers

ALTHOUGH the process to which I refer in this paper has been in successful operation for nearly five years, during which time it has been introduced, superseding all other processes having in view the same end, in almost every lead refinery in the country, no description of it, giving economical data, has ever appeared in print, nor has the process been known in its details to any considerable number of engineers beside those conducting it at their works. A discussion of this subject at the present time becomes especially interesting in view of a late publication in the Prussian ministerial organ for Mining and Metallurgy, by Dr. Wedding, in which the method of treating the zinc-silver-lead alloy by distillation, as finally settled upon at Tarnowitz, is very minutely and fully described. It is the more interesting, because in that article reference is made to the American method in an unfavorable light, while, at the same time, it is clear from the article itself, that the most important details of the process, besides the one that it is conducted in black-lead retorts, were not at all understood. In publishing herewith the details of our American method, one of my objects is to invite comparisons between our simple and direct process and the elaborate one at Tarnowitz. In extracting the silver from work-lead by means of zinc, it is always the intention, in this country, to obtain a zinc-crust so rich in silver that the rich lead resulting from subsequent distillation

Jan 1, 1875

By Clarence A. Seyler

The object of all classification is to group together things which are alike, and separate those which are unlike. This object is essentially a practical one, enabling us to apply past experience to new conditions. Many costly large-scale experiments lose half their importance for want of proper description of the coal used, and the consequent impossibility of predicting that other coals will behave in the same way. I do not, therefore, make a fundamental distinction between "scientific'' and "use" classifications, except in so far as use depends on conditions, such as size or impurities which are not related to the nature of the coal substance itself. The characters chosen to define the classes of coal must be such as are accompanied by as many other properties as possible. It is not to be expected that any system of classification will enable us to predict every property of coal, since all specimens have an individuality of their own. But specimens can be grouped by a number of resemblances into species. Further, species which resemble each other can be grouped into genera. Elementary Composition as a Basis of Classification There can be little doubt that the ultimate or elementary composition of "pure coal" is the best basis of classification. It was soon after the perfection of the method of elementary analysis of organic substances by Liebig that Regnault, the distinguished chemist and physicist, laid down the principle that coals of the same kind vary only between narrow limits of elementary composition. This is still the widest generalization that can be made about coal. Upon it the metallurgist Gruner based his classification. In some quarters the value of the ultimate composition was denied, Stein going so far as to say that it teaches us nothing of importance about coal. One still hears statements that it is like crushing a work of art in a mortar and analyzing the powder, or like counting the number of times a given letter occurs in a sentence. Such comparisons are misleading, and the criticism might be applied to organic chemistry as a whole. Nor is the existence of isomerism, or of entirely different substances which

Jan 1, 1928

By E. E. Bach

STATEMENT OF THE PROBLEM THE administration of industrial organization today embraces more than the cost of production and selling prices. Competition is deeper seated than mechanical devices, overhead charges, and a shrewd manipulation of the markets. Despite the "down-to-the-minute" equipment and the "last word in organization," it is quite evident that "capacity production" will be an unknown quantity until the workman is considered as a producer, in relation to his home, as he is now considered in relation to industry. Whether or not a man shall do an honest day's work is as much a psychological condition as it is a matter of physical strength or skill. His attitude toward his work each morning is determined, to a large degree, by the environment of his home. Whether this attitude, good or bad, obtains the day through will depend entirely upon the one fact as to whether the corporation which employs him does or does not differentiate between the mechanical factor and the human factor in industry. To be more specific, sociological work, under whatever name, should be of such a character as to influence the life of a workman in such a manner as to establish a cooperative interest in his work, foster within him a spirit of contentment in his home, lead him-so to employ his leisure time that he will not lower his efficiency as a workman, destroy his domestic happiness, or endanger his standing in the community as a citizen. While no fixed rules of procedure can well be formulated for the development of the work, yet definite lines of activities will readily present themselves as applicable to the individual needs of a community. This is especially true where community influences and agencies pertaining to general welfare are easily correlated.

Jan 2, 1918

By John P. Ashby

Mine production blasting is a process of destruction of rock masses in order that ore may be extracted. Many open pit operations are faced with the apparently conflicting requirements of providing large quantities of fragmented rock for the processing plant and of minimizing the damage inflicted upon the surrounding pit slopes. A reasonable compromise between these two conflicting demands may often be found by means of simple engineering of production blasts. Many operations tend to rely too heavily upon traditional wall control techniques to alleviate a problem already created by the production blasts. Various production trends including use of larger blastholes and patterns have tended to aggravate the situation. These practices only serve to emphasize the need for engineered improvements. Central to blasting engineering is the process of systematic trial and evaluation. Changes to the blasting system should be made singly, starting with the simplest. This paper discusses simple changes involving drill pattern control, effective use of blastholes and explosives, adequate delaying including use of down-the-hole sequential techniques, effective utilization of free faces, and avoidance of "choked" situations. By directing explosive effort where it is needed, such changes generally result in a significant improvement of slope conditions and of production blasting cost and performance.

Jan 1, 1983

By Plato Malozemoff

Our young, technically oriented people today are entranced by the space program, by physics that unlocks the secrets of nature, by electronics, and by other new technologies. The mining industry seems to be their last choice. Enrollment in mining schools is dropping and so is the interest of our great universities in mining curricula. The image of the mining industry appears to be one of being conservative, nonprogressive, resistant to change, and lacking in excitement and challenge. I submit that this public image is wrong. While the initial development of mines is usually slow and seemingly plodding, the problem of solving the imponderables of nature-the ore emplacement, its structure and physical characteristics, its response to recovery processes, and its probable ultimate profitability-is stimulating to the most acute and searching of minds and requires careful application of a combination of many technologies. The paths to obtaining the desired results must be within the bounds of reasonable expenditures in the early stage of development when risks are still high, and this financial discipline is a further stimulus to the imaginative search for the right answers.

Jan 6, 1968

By H. B. C. Nitze

A description of some of the magnetic ore-deposits in this region should be of interest to the mining and metallurgical public, inasmuch as very little has been said or written concerning them. I refer to the magnetite deposits of Franklin and Henry counties, Va., and of Stokes county, N. C. These deposits remained comparatively unexplored until recently, when the construction of the Roanoke & Southern R. R. through this territory has called attention to them, by furnishing the means of transportation for the ores. It is true that the ores have long been known, at least locally, and were smelted in catalan forges and old-fashioned, cold-blast charcoal-furnaces long before and during the late war. At the present time, however, the old workings are caved in, filled up and over-grown to such an extent that, as a rule, but little can be learned from them. No prospecting of any consequence has been done, and as my time was too limited and the territory to be examined too extensive to permit additional openings of a more satisfactory nature to be made, the incormpleteness of some of the data I have to offer (notably, those referring to the absolute width of the veins) will be pardoned. It will hardly be necessary to say that this ore-bearing formation belongs to the Archaean, or Eozoic age, the usually occurring rocks being schist, shale, gneiss, granite, sandstone and quartzite. The stratigraphy is, as a rule, quite regular (excepting in the Danbury section, Stokes county, N. C.), the general strike being northeast and southwest, and the dip nearly vertical. The country is gently roll-

Jan 1, 1892

By Hans Haalk

PRACTICAL or applied geophysics-as we designate the border region between physics and geophysics on one hand and practical geology on the other-has as its object the application of physical or geophysical methods of investigation to problems of practical geology. Its field of operation comprises all methods of physical measurement that are used in the problem of determining, from the geophysical influences of the subsoil that can be measured at the surface of the earth, the special characteristics of the association of strata, faults, etc., to detect the presence of deposits and to investigate underground structures. It therefore repre-sents an aid, a physical method of research in practical geology, and is inseparably connected with geological studies; for this reason, it is also called geophysical prospecting. Formerly research methods of practical geology were based on observation exclusively: first, on the observation of the strata and formations at accessible parts of the surface of the earth, especially in shafts, borings and mines if such were available; then on the observation of the tectonic conditions in so far as these were already known at places directly visible; and finally, by estimation of the importance of formations of the terrane. Later, there were added in special cases, analytical chemical crystallo-graphical, petrographical and similar investigations of rock samples which were taken from the places under consideration. The knowledge thus obtained is of value and is expanded by hypotheses and constructions that are supported by geological theories of origin and by laws of the sequence of formations and rock systems, which are based on long experience.

Jan 1, 1928

By J. R. Low, A. M. Turkalo

ManY qualitative observations have been made concerning the relationship of the carbide dispersion and the mechanical properties of steel. With reference to the strength and hardness we know that for a given composition a steel having a fine pearlitic structure is stronger than that having a coarse pearlite. The martensitic structure tempered at a relatively low temperature and having finely dispersed carbides gives greater strength than that given by the martensitic structure tempered at a relatively higher temperature and having a coarser

Jan 1, 1959

By John A. Church

AT a time when the treatment of gold and silver ores by fusion, in opposition to the mill-process, is attracting so much attention in this country, it may be useful to consider what is done in a well-conducted foreign work. For this purpose I will ask the reader to accompany me to Lend, in Austria, a small but thoroughly organized

Jan 1, 1873

By Lawrence A. Garfield

From the bottom of a shallow fissure the near-naked man-animal hacked out a hand-sized chunk of the red rock-like material which, when beaten between other rocks, could be drawn out to the thinness of a flint edge. Unlike flint, however, it did not shatter when, as the point for a spear or arrow, it went wide of its mark and fell amongst the rocks or tree branches. For this reason and others, the red rock- like material was specially sought and much time was spent in trying to break it from the real-rock in which it grew. Only infrequently was a chunk broken free and in this area many hours had been spent to win but a few fragments. What luck then, to remove so large a piece where before nothing but real-rock dust formed whenever the stone hammer hit. Why did this happen? Did yesterday's food-fire, burning on top the red rock, loosen its hold on the real-rock and cause it to break free when struck with the stone hammer? It is not a matter of recorded history that the first heat assisted extraction of native copper from country rock occurred under the circumstances or in the manner related but it is known that crude mining operations using these techniques were conducted by primitive man. In this way the first mineral production may have been achieved and the original example of rapid excavation unknowingly given to the world. Rapid excavation is not a method of removing rock or ore from an insitu condition nor does the term refer to a type of equipment which is specifically employed in mining and underground construction. It is, rather, the nomenclature currently popular in industry-primarily in underground construction- relating to a comparative rate of performance.

Jan 1, 1971

By John W. Padan, Thomas E. Howard

Most of what has been written during the past few years on marine mineral resources has emphasized the vast potential of the ocean, and its floor, as a source of the vital mineral raw materials upon which our modern technological society depends. Computations have been made to demonstrate that the sea contains sufficient minerals to support any reasonable world population indefinitely. The importance of these resources from the standpoint of strengthening the national mineral resource base has been pointed out. And though the information upon which these conclusions are based is sketchy, essentially qualitative, and often conflicting, there can be no doubt that the mineral potential of the sea is tremendous and that there are compelling reasons for working toward its exploitation. Unfortunately, there has been little emphasis on the problems that must be overcome, from the perspective of the economics of mineral production. Some of these problems have been noted, and some authors have appraised them realistically. However, many proposed solutions have been more romantic than practical, from the standpoint of both technology and economics. As a result the general impression has been given, particularly to those uninitiated in the realities of mineral production, that the mineral wealth of the sea is there for the taking-requiring only a good modicum of courage and technologic innovation to place it within easy grasp. But developing the capability necessary for substantial, profitable production of sea bottom minerals will be far from easy. It will be accomplished much more quickly if the problems are faced squarely, defined properly, and attacked in an orderly, logical sequence. While this approach may lack glamour, it offers the highest probability for success.

Jan 6, 1966

By M. K. Barnett

Engineering research consists, broadly speaking, in the investigation of the effect of the variations in a number of factors on some property of a product or characteristic of a process. The unambiguous description of the product or process requires that the property or characteristic be expressible in quantitative terms. For the purpose of practical control, it is likewise desirable that the independently variable factors governing the product or process be quantities, although this ideal goal is not always attained. Maximum efficiency—i.e., the attain- ment of the maximum amount of reliable, useful information relating to the influence of, the factors on the property of the product or characteristic of the process, for the least expense—is an important requirement for the satisfactory operation of a research organization. Obviously, a necessary condition for the attainment of maximum efficiency is an adequate knowledge of the specialized field in which the experimental research lies. While necessary, this condition is not sufficient. Proper attention must also be given to the general principles of experimental design together with the modern methods for the analysis and evaluation of experimental data. The Present discussion is confined to a single design, the so-called "factorial" design. This design is of special interest in that it attains its goal, maximum efficiency, by directly departing from the

Jan 1, 1948

By M. K. Barnett

Engineering research consists, broadly speaking, in the investigation of the effect of the variations in a number of factors on some property of a product or characteristic of a process. The unambiguous description of the product or process requires that the property or characteristic be expressible in quantitative terms. For the purpose of practical control, it is likewise desirable that the independently variable factors governing the product or process be quantities, although this ideal goal is not always attained. Maximum efficiency—i.e., the attain- ment of the maximum amount of reliable, useful information relating to the influence of, the factors on the property of the product or characteristic of the process, for the least expense—is an important requirement for the satisfactory operation of a research organization. Obviously, a necessary condition for the attainment of maximum efficiency is an adequate knowledge of the specialized field in which the experimental research lies. While necessary, this condition is not sufficient. Proper attention must also be given to the general principles of experimental design together with the modern methods for the analysis and evaluation of experimental data. The Present discussion is confined to a single design, the so-called "factorial" design. This design is of special interest in that it attains its goal, maximum efficiency, by directly departing from the

Jan 1, 1948