Search Documents

By AIME AIME

THE 1944 Chairman of the Institute of Metals Division might be classed as metallurgically ambidextrous ; he is teacher of theory and practice of both nonferrous and ferrous metallurgy, and he is consultant on brass and on highspred steel. Arthur Phillips was born in Troy N.Y. and attended the New Haven Connecticut high school. Upon graduation he entered Yale, receiving a degree in metallurgy in 1913. At that time Professor Mathewson was starting his plan of '"co-operation with the metal industries in metallographic work at the Hammond Laboratory of the Sheffield Scientific School, Yale University, and Arthur Phillip, became the first co-operative graduate student, working in the laboratory of the Bridgeport Brass Co., and receiving his Masters of Science degree in 1915. A little later, when the department of metallurgy at Yale was expanded. Me. Phillips was appointed assistant professor. In 1928 he was made associate professor, and in 1934 he was promoted to full professor.

Jan 1, 1944

By F. Lowell Lawrance

JOHN SMITH, citizen of the U.S.A., has become so accustomed to reading that Congress has appropriated billions of dollars to pay war costs. that he no longer is impressed by relatively small figures, such as several hundred thousand or a few million, in connection with Government departments.

Jan 1, 1944

By Tell Ertl, Will Mitchell

THE Mineral Industry Education Division made the headlines when Columbia's President, Nicholas Murray Butler, welcomed it in a provocative address made before a record crowd of over 100 members attending the opening Sunday session in the Columbia Men's Faculty Club. Arthur F. Greaves- Walker, Chairman of the Division, who was presented by H. R. Hanley, told of the excellent job of war research being carried on in the colleges. E. A. Holbrook led a discussion on the unionization of engineers, stating that he had learned that professional engineers were being forced into unions by subprofessionals. This might become a serious problem if the professional engineering organizations are lax in combating the

Jan 1, 1944

By Milnor Roberts

WAR struck the mineral industry of Washington with cross currents that produced a peculiar result. The State's production of coal, industrial minerals, and metals for 1941, valued at $28,507,282, was increased in 1942 under war pressure to approximately $35.000,000. Meanwhile a tremendous demand had arisen for men to construct airfields and many other large projects for the Army and Navy in Washington and Alaska, and Government plants for the mineral industry costing $140,000,000 or more, as well as a call for employees in the U. S. Navy Yard at Bremerton, the sixty shipyards, the four Boeing airplane factories with many auxiliary shops, and hundreds of other plants turning out war materials. In spite of an influx of nearly 300,000 people, causing an increase of 17.1 percent in the population since 1940, according to the Census Bureau, the State clearly is still engaged in an unusual amount of war production in proportion to its population. A large proportion of the workers have been drawn from the mineral industry to the war plants, whether through motives of patriotism, high wages, or, in the Boeing plants at least, the glamour of the operation

Jan 1, 1944

By O. W. Shimer, D. C. Helms, C. E. Brown

THE early history and progress of anthracite stripping, from the first known operation at Summit Hill in 1821 through 1917, was covered in 1917 in a paper by J. B. Warriner,1 then chief engineer, now president of the Lehigh Navigation Coal Co., and stripping methods between 1917 and 1931 were the subject of a paper in 1931 by H. H. Otto,2 of the Hudson Coal Company. The present paper is confined to methods used today on pitching beds in the western middle and southern anthracite fields. The anthracite industry, not unlike other large industries, had been affected for more than a decade by the adverse economic conditions of the country. High development and operating costs and the competition of other fuels caused some collieries to be closed temporarily, while others were permanently abandoned. In order to obtain a larger tonnage at a lower development cost, a larger stripping program was put into effect by many companies. In 1932, stripping operations accounted for 334 million tons, or 7 per cent of the total anthracite production of the year, and in the next 10 years this increased until more than double that amount, or over 14 per cent of the total production, was from stripping operations. These figures represent the total production of the entire anthracite region; unfortunately, the figures have not been separated from the different fields. There are some operations in the southern and middle western fields where the tonnage obtained from stripping amounts to more than 30 per cent of the total colliery production. Stripping operations on pitching beds present difficult problems. Owing to the various geological formations, a different situation is encountered in nearly every stripping pit; and because of the proximity of an overlying bed, it is very often necessary to load the entire overburden into trucks and haul it out of the pit to the dump area, although back filling and casting is done whenever possible. Beds in the areas described in this paper pitch from 20° to 90° and some are on the invert in, many sharp folds and faults. PLANNING The more successful strippings have had adequate engineering analysis. Some work is being done without much preliminary planning, but many strippings would have failed completely if close supervision by the engineering department had not been maintained. Locations of stripping areas are determined as follows: 1. By constructing cross sections over the areas and drilling sufficient diamond-drill or well drill holes to study the strata and to determine the location, thickness and pitch of the beds.

Jan 1, 1944

By R. P. Smith

IN 1937 the employees of the Hollinger Consolidated Gold Mines Ltd., at Timmins, Ont., Canada, approached organized medicine for a plan to provide themselves and their families with a complete medical service including hospitalization. This approach was made because of two conditions: (1) the necessity for some organization whereby contributions could be made in instalments to offset the sudden and large expense connected with illness for which the average employee is not prepared, and (2) the need for a more cohesive quality of service to replace a contract practice then in vogue, which did not take care of the employee's family or dependents. In different parts of the United States and Canada similar plans were in force, not only for employed groups but for numbers of people in circumscribed areas. In Europe different countries had adopted various forms of health insurance plans. It then was no surprise that these employees as a group should ask for some similar plan. With the cooperation of the management, a plan was instituted. The plan has one object only-the provision of medical services, including the accessory services such as hospitalization, X-rays, nursing, and necessary drugs and medicines. It is not concerned with cash benefits, sickness and accident payments, or any form of monetary return as the result of illness, but is simply an organization to provide medical services and pay for them from a central fund. It is a nonprofit organization and the only shareholders are the employees and their families who contribute and who in turn receive services. The Hollinger plan is limited to the employees of the Hollinger mine, who live in Timmins and the immediate vicinity. At first, the membership was voluntary. In the third year, it was made a condition of employment, with the proviso that at the end of any Association financial year an employee may withdraw if he wishes to do so. After withdrawal, he cannot again become a member until the end of the next Association year, and then only by the payment of the back dues. This step was taken to ensure continuity, and to prevent employees from withdrawing when well and reentering when faced with impending illness or operations. The employee himself is subject to medical examination on application for employment, and if accepted is subject to further examination by a specialist in chest diseases under the Workmen's Compensation Board of Ontario. Thus it is possible to exclude those who have heart disease, tuberculosis, or other disabling conditions when first employed. Wives and families of employees are not subject to medical examination but other dependents of an employee-mother, father, or other relative-who are declared by the employee to be wholly dependent upon him must be examined. The employee

Jan 1, 1944

By D. K. Crampton

ON giving thought to the subject of this paper, my first reaction was that many and striking changes have come about as a direct result of the war. However, more careful analysis indicates that few, if any, of these changes can be wholly attributed to it. The actual situation is that all these changes were conceived and most of them at least partially executed in re- cent prewar years, it remaining the role of war to achieve results in a fraction of the time that might normally have been taken, lacking its driving impulse. The further discussion will therefore be with the premise that the individual changes have been greatly hastened rather than directly and primarily caused by any war conditions. Co-operation among copper alloy producers on production problems is agreed to be much worth while. The industry was too long noted for jealousy and secrecy as to equipment, methods, and even materials produced. Gradually, a more open and co-operative policy evolved but even just prior to the war the interchange of ideas was relatively cautious and limited. The need for a great increase in production in record time fostered a more co- operative attitude; exchange of ideas and experience concerning all phases of production increased tremendously to the benefit of the individual participants and thus the war effort, too. This more united effort has undoubtedly led to many specific improvements in process or equipment and these in turn to more rapid and economical operation than could have taken place on an each-for-himself basis.

Jan 1, 1944

By AIME AIME

PRODUCTION of nickel in Cuba, a new source of this metal, has been started by the Nicaro Nickel Co., subsidiary of the Freeport Sulphur Co. Construction of the Nicaro plant in Oriente Province, Cuba, and of a refinery at Wilmington, Del., has been "substantially completed," according to Langbourne M. Williams, Jr., president. The initial rate of output is less than capacity operation, which will be reached when "the customary problems incident to the commencement of full- scale production are eliminated." The plant in Cuba for the treatment of the extensive nickeliferous ores of that region, and the refinery, were built by Nicaro for the account of the Defense Plant Corp. construction has been under way for eighteen months. The plants, when operating at capacity, are expected to increase America's sup-

Jan 1, 1944

CONTENTSThe significance of values givenINTRODUCTIONTHE ORE1. DATA SECURED FROM THE MILLING PLANT AS OPERATING BETWEEN 1938 AND 1942(a) Mill Recoveries(b) Mill Flow Sheet(c) Scheelite-Garnet Association(d) Detailed Examination of Mill Performance during 1942Crushing UnitsCoarse Rolls DischargeFine Rolls DischargeFeed to Huntington MillsFinal Ground ProductProduction of -200-mesh Scheelite SlimeSummary of Information on Crushing and Grinding Circuit(e) Detailed Examination of Mill Performance During 1942Concentrating UnitsLocation and Nature of Scheelite LossesSize Distribution of Scheelite LossesDistributor Spigot ProductsSummary of Information on Concentration Circuit(f) Detailed Examination of Mill Performance During 1942 Gravity Plant Feed2. EXAMINATION OF MINE SAMPLES TAKEN DURING 1942(a) Introduction(b) Nature of the Ore(c) Sampling of Mill Feed(d) Testing Technique(e) Minus 1/8-inch Ores-Naturally Broken Fractions(f) Recoveries from Plus 1/8-inch Fractions-Crushed to Minus 1/8-lnch(g) Probable Recoveries Obtainable from Weathered Ores140 Contour120 Contour90 Contour(h) Examination of an Ore Sample from the 90-foot Adit(i) Run-of-Mine Ore(j) Evidence of Maximum Sizes of Scheelfte Present in Run-of- Mine Ore(k) Summary of Information on Liberation and Recovery from the Ores as Mined in 1942 and from the Mill Samples

Jan 1, 1944

By O. W. Shimer, D. C. Helms, C. E. Brown

The early history and progress of anthracite stripping, from the first known operation at Summit Hill in 1821 through 1917, was covered in 1917 in a paper by J. B. Warriner,1 then chief engineer, now president of the Lehigh Navigation Coal Co., and stripping methods between 1917 and 1931 were the subject of a paper in 1931 by H. H. Otto,2 of the Hudson Coal Company. . The present paper is confined to methods used today on pitching beds in the western middle and southern anthracite fields. The anthracite industry, not unlike other large industries, had been affected for more than a decade by the adverse economic conditions of the country. High development and operating costs and the competition of other fuels caused some collieries to be closed temporarily, while others were permanently abandoned. In order to obtain a larger tonnage at a lower development cost, a larger stripping program was put into effect by many companies. In 1932, stripping operations accounted for 3½ million tons, or 7 per cent of the total anthracite production of the year, and in the next 10 years this increased until more than double that amount, or over 14 per cent of the total production, was from stripping operations. These figures represent the total production of the entire anthracite region; unfortunately, the figures have not been separated from the different fields. There are some operations in the southern and middle western fields where the tonnage obtained from stripping amounts to more than 30 per cent of the total colliery production. Stripping operations on pitching beds present difficult problems. Owing to the various geological formations, a different situation is encountered in nearly every stripping pit; and because of the proximity of an overlying bed, it is very often necessary to load the entire overburden into trucks and haul it out of the pit to the dump area, although back filling and casting is done whenever possible. Beds in the areas described in this paper pitch from 20" to 90 and some are on the invert in many sharp folds and faults. Planning The more successful strippings have had adequate engineering analysis. Some work is being done without much preliminary planning, but many strippings would have failed completely if close supervision by the engineering department had not been . maintained. Locations of stripping areas are determined as follows: I. By constructing cross sections over the areas and drilling sufficient diamond-drill or well drill holes to study the strata and to determine the location, thickness

Jan 1, 1944

By R. S. Dean

As set forth in the decision of the Trail Smelter Arbitral Tribunal, dated April 16, 1938 This Tribunal is constituted under and its powers are derived from and limited by the convention between the United States of America and the Dominion of Canada signed at Ottawa, April 15, 1935, duly ratified by the two parties and ratification exchanged at Ottawa, August 3, 1935 (hereinafter termed "the Convention") . . . The duty imposed upon the Tribunal by the Convention was to "finally decide" the following questions: (1) Whether damage caused by the Trail Smelter in the State of Washington has occurred since the first day of January 1932, and, if so, what indemnity should be paid therefor? (2) In the event of the answer to the first part of the preceding Question being in the affirmative, whether the Trail Smelter should be required to refrain from causing damage in the State of Washington in the future and, if so, to what extent? (3) In the light of the answer to the preceding Question, what measures or regime, if any, should be adopted or maintained by the Trail Smelter? (4) What indemnity or compensation, if any, should be paid on account of any decision or decisions rendered by the Tribunal pursuant to the next two preceding Questions? In this decision reported to the Government of the United States of America and to the Government of the Dominion of Canada, the Tribunal answered the first question in its entirety and reserved decision on the other three questions in accordance with the following extract from their decision

Jan 1, 1944

By W. A. Selvig

"INTRODUCTION In 1942, Lowry and Junge 3/ reported the results of a statistical study of errors for the proximate and ultimate analysis of coal and coke when made according to the standard Methods of Laboratory Sampling and Analysis of Coal and Coke (D271-42) 4/ of the American Society for Testing Materials. Some of the laboratories that cooperated in the investigation reported difficulty with determination of the volatile matter of anthracite and low-temperature coke. The small number of analyses reported for these particular fuels was considered inadequate to justify definite conclusions regarding the precision of this determination.The investigation described in this report was made at the request of Committee D-5 on Coal and Coke, A.S.T.M. (A. C. Fieldner, chairman), to secure additional information regarding the errors of the volatile matter determination for anthracite, low-temperature coke, and subbituminous coal; the last fuel also gives trouble in this determination, The committee has recognized that the allowable differences between duplicate determinations of volatile matter for these fuels as given in the standard methods are perhaps too stringent and may require revision."

Dec 1, 1943

By Griffith. F. E., Glei

"INTRODUCTION For many years protective grounding of electrical equipment has been advocated as a means of safeguarding equipment against damage and of minimizing shock hazards to persons. Several codes are in effect covering in considerable detail the items to be observed in obtaining effective grounding in and about industrial plants. Although the coal-mining industry does not have a comprehensive code of its own covering the grounding of electrical installations, a number of States and individual coal-mining companies have issued codes, standards, or rules that include certain requirements with reference to grounding. As early as 1916, 4/ and again more recently, 5/ the Bureau of Mines recommended grounding, particularly as a means of preventing shock to men working on or around electrical equipment.It is common knowledge among electrical engineers of public utility and mining companies that connecting a wire from the frame of a machine to a rod or pipe driven into the earth does not necessarily assure desired protection of surface equipment. In fact, it has often been found necessary to use several interconnected rods and to treat the surrounding earth with salt or other chemicals before the connection to earth would have sufficiently low resistance to give satisfactory results. Even these expedients have not produced the desired results in some localities. It has also been found that ground connections initially having a low resistance may attain high resistance during some seasons of the year. In spite of such difficulties with surface equipment, it has sometimes been assumed that a mining machine resting on the floor in a coal mine is grounded by virtue of its contact with that floor. It has also been assumed by persons endeavoring to comply with grounding requirements that a peg or rod driven into the mine floor would provide a sufficiently low-resistance contact with the earth to be satisfactory as an electrode for connecting the grounding wire from frames of equipment. That both assumptions may be wholly untrustworthy has been proved by the authors in actual tests with underground machinery."

Dec 1, 1943

By G. S. Scott, L. D. Schmidt, J. A. KELLEY, E. L. FISH

One of the war problems with which the Bureau of Mines is concerned is to increase production of iron and steel , in which coke is one of the major factors . The output of byproduct coke for use in iron blast furnaces is insufficient and is being supplemented by coke from beehive ovens (figs . 1 , 2 , and 3) . Some difficulties that cause a reduction in iron output have been reported in the use of some of the beehive coke.6/ About 20 years have elapsed since beehive coke was made on a large scale , and many of the skilled operators of those days are no longer available . Furthermore , in many instances the quality of the coal supplied to the ovens has not been as good as formerly. The ash and sulfur contents are often abnormally high; and in other instances they vary greatly in amount, so that a nonuniform coke is produced . To assist operators to improve quality and yield of beehive coke , the Bureau of Mines equipped a truck as a field laboratory ( fig . 4 ) and sent the authors with it into the Pennsylvania beehive district . The truck contains necessary equipment for sampling and analyzing coke oven gases , measuring temperatures , screen - sizing coal, and float -and - sink testing coal . Coal specimens may be sent to the Pittsburgh laboratory for analysis . Beehive plants producing good coke were visited first to observe details of operation and to collect data on the operating process . These covered temperatures , analyses of the exit ( or trunnel) gases , and coal quality, and were to be utilized in searching for faults in plants not producing good - quality coke and to assist in improving such plants or their operation .

Dec 1, 1943

By J. E. Tiffany, Z. C. Gaugler

In presenting this list of permissible explosives and blasting devices , the Bureau of Mines desires to call attention to pages 16 and 23 , outlining the conditions in use under which , and only under which , the explosive or blasting device is permissible . In view of publications recounting trade practice favoring the use of a blasting device without stemming , particular emphasis is placed upon condition 4 on page lt and condition 2 on page 23 .. An explosive or a blasting device enumerated in the permissible lists of this Bureau is not permissible in use unless it is properly confined with clay or other incombustible stemming .

Dec 1, 1943

By ROBERT R. ROUGH, FRANK L. BACON, John Dasher

(being shipped as bailast in ocean freighters). Within the last 10 years it has become more economical to use local sands, and there has been a general shift from the Belgian sand. Deposits of purer sand were treated and used for 'some time: but the suprly became limited, and means were sought to beneficiate the more bountiful subpay-f impure beach sands. These sands are composed of, 50 percent feldspar and 50 percent quartz, with small amounts of iron- bearing minerals, The most objectionable impurities in these West coast sands are the oxides of iron and aluminum. The Del Monte (Calif.) beach sand contains about 0.13 percent FeqQg and about 11.0 percent Aig03 (the latter being furnished by the large amount of feldspar present.) For the manufacture of feldspar present.) For the manufacture of flint-glass containers the maximuni quantities of these two impurities permitted in the sand are 0.05 percent F20 and 6 to 8 percent A1203.. The Fe0g occurs in the sand as follows: Traces of iron-bearing minerais resistant to weathering, ferruginous clay stains on the sand grains, and iron minerais not visible and possibly in solid solution or as colloidal incisions in the grains of feidspar or quartz. A good part of the iron in the sand is present in the traces of iron-bearing minerals, biotite, ilmenite, garnet, monazite; and hornblende. Biotite is present in larger quantities than the others. Samples of quartz, were freed of iron-bearing minerais by the use of heavy liquid (sp.gr. 2.70), leached with boiling HCI and SnCl2. Under a microscope a few apparently clean quartz grains were selected, and Fe203 was determined spectrographically to be 0.03 percent. The technique is similar to that described by Gabriel and Slavin. 4/

Dec 1, 1943

By Albert L. Toenges, Louis A. Turnbull, Henry E. Dekay, James N. Scudder

A preliminary survey of coke and steel plants conducted by the Bureau of Mines in cooperation with the Office of Solid Fuels Coordinator and under the auspices of the Coke Production Committee indicated that a very appreciable increase in pig-iron production would be obtained if pres- ent blast furnaces were supplied with a more uniform coke. Control of the sulfur and ash content of coal used for making coke is an important factor in producing uniform coke and thus increasing blast- furnace efficiency. In some mines producing metallurgical coal, the analysis of the coal bed shows a wide range of sulfur and ash content. To obtain production of coal with minimum deviation in sulfur content sampling, grading, selective mining, blending, and surface preparation are practiced at some mines with satisfactory results. The mines selected for this study have developed these methods and are successfully producing coal of uniform sulfur and ash content. The systems employed at different mines vary according to the physical character- istics of the coal bed, the manner of occurrence of impuritites in the coal, the development plan and mining system, surface preparation and the acceptable impurity content of the prepared coal. The ash content of the coal can be controlled by face preparation and in the cleaning plant. The introduction of some method or practice at other mines might make possible the use of coal for inetallurgical purposes that otherwise could not be used for making coke because of the wide variation of sulfur and ash content.

Dec 1, 1943

By G. S. Scott

It is sometimes desirable to know what changes in sizing characteristics would appear in screened coals if screens of different - size openings than those employed had been used . This report is concerned entirely with the application of the Rosin- Rammler law to a solution of this problem .

Dec 1, 1943

By E. W. GOODWIN, V. F. Parry, J. B. Goodman, L. D. Schmidt, J. D. Davis, A. C. Fieldner, W. S. Landers, J. L. ELDER

The Heliopore process is essentially an arrangement that uses the waste heat in the exhaust gas of an internal - combustion engine to carbonize coal (noncaking ) or lignite . The gases distilled from the coal furnish fuel for the internal - combustion engine , which drives an electric generator . Thus the main products of the plant are electricity and char . A flow diagram illustrating the principles of operation of the Heliopore process is given in figure 1. The primary equipment consists of a carbonizing retort , gas cooling and scrubbing equipment, a gas storage holder, and an engine to burn the gaseous carbonization products . Coal is charged into the top of the retort while the hot gases from the engine travel upward through special ducts in the retort countercurrent to the coal flow . The hot gases never come into direct contact with the coal . Char is discharged at the bottom of the retort and hot gases at the top . The gaseous products resulting from carbonization of the coal are drawn off by an exhauster through the condensing and scrubbing equipment to take out tar and liquor , then to a gas holder , and finally are burned in a gas engine . The gas engine drives an electric generator and the engine exhaust gases are returned to the retort to carbonize coal . The entire process was intended to be continuous and self - sustaining, and to use coal as the only fuel . The plant may be said to be a large - scale pilot plant in that , although it is of full commercial size , its main purpose is to provide data for the design of others of its type . The installation tested had a daily throughput of about 4 tons of coal . Figures 2 , 3 , and 4 picture some details of the plant and equipment used in the experimental testing . Further details of the equipment and engineering drawings of the castings are shown in figures 8 to 22 in the Appendix .

Dec 1, 1943

By William Seymour, L. D. Schmidt

A preliminary survey of coke and steel plants conducted by the Bureau of Mines in cooperation with the Office of the Solid Fuels Administrator for War and with the advice of the Coke Production Committee indicated that production of pig iron could be increased. appreciably if present blast furnaces were supplied with a more uniform coke.4/ Nonvarying percentages of ash , sulfur , and fixed carbon in the coke , together with uniform physical characteristics , such as size , strength , and porosity , would aid the blast -furnace operator greatly in his trial - and - error methods of obtaining maximum production . With nonuniform raw materials he must employ certain factors of safety in operation , such as an excess of coke , an excess of limestone , and operation of the furnace below the maximum rate . Even so , he often has trouble from iron not being up to specifications , hot tops , high blowing pressures , furnace hanging up , etc. The more uniform his raw materials (of which coke is probably the most important) , the nearer to ideally can he run his furnace and thereby save raw material and increase production . One cause of nonuniformity of the coke produced by ordinary American plant practice is the prevailing lack of precise control of the bulk density ' of the coal charge in the byproduct oven . This report summarizes the available information on the subject of bulk density of crushed coal and its control . It includes brief reviews of some of the literature , some results obtained at plants visited by the authors , and results of a few preliminary tests made at the Pittsburgh Station of the Bureau of Mines .

Dec 1, 1943