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By Edo Engel

Blast furnace No. 3 at Zaporizhstal in Zaporozhye is rebuilt in 2016-2017. The Ukrainian company is targeting increased production and availability, mainly through the use of new technology. Zaporizhstal awarded a contract for a new Top Charging Unit to Danieli Corus, after comparing all available technologies. Reliability of the chosen charging device is pivotal, since long outages may be required for maintenance/replacement jobs, which strongly affects the availability of the blast furnace. This article describes the Top Charging Unit including DANCU (Danieli Charging Unit) - a robust hydraulic system. The main focus employed by Danieli and Danieli Corus during the development of this system has been availability and maintainability of equipment. This chute type charging unit has only few major moving parts, none of which is complex or vulnerable. The article also describes the main challenges of the project at Zaporizhstal, such as the use of hot sinter.

Oct 30, 2017

By Ralph M. Barnett

It is no longer a question of "If" mining operations will meet standards and regulations set by various governing bodies and the demands of citizen groups. Legislation is fact. The needs of citizens are becoming more of a integral part of mining company planning. "Open Planning", regardless of some frustrations it provides, is working. Climax, AMAX Chemical and AMAX Exploration are successfully employing several citizen involvement techniques in exploration and feasibility study phases of planning for potential new mines.

Jan 1, 1978

President H. M. Howe, Boston, Mass. (communication to the Secretary): Le Chatelier's pyrometer is certainly a most convenient and accurate instrument for the laboratory, and one that may be used under some conditions in the mill. I have used it for several years and with great satisfaction. Like Prof. Roberts-Austen and unlike Herr Blass, I have always found that its indications remain constant over long periods. Like Prof. Roberts-Austen, also, I find it possible, in a quiet place, to read with extreme accuracy ; and, by the use of a telescope, I can read temperatures to within a degree, for some delicate determinations which I have in hand. Variations in the temperature of the room affect the readings of the instrument far less than one would expect. When the current is cut off, the mirror does not always return exactly to the same place; in other words, the zero shifts appreciably, and must be determined often, indeed every few hours if accuracy be desired. In some cases I have had it determined within a very few minutes of every important reading. To this end a switch should he introduced, so that the circuit may be broken readily. With this arrangement we can determine accurately the position of the zero within a very few seconds of the time of taking any especially important reading. The chief causes of the variation of the zero which I have noticed are as follows: a. The suspension may not be tight enough, so that the momentum of the galvanometer frame as it swings makes its supporting wires slip in their bearings. b. Changes in the position of neighboring iron objects may deflect the mirror. c. Changes in the temperature of the room may, perhaps, change the torsion of the suspension wires, and so shift the mirror. d. Dust may attach itself to the galvanometer frame, and by friction against the surrounding fixed parts of the galvanometer, may

Jan 1, 1895

The problem of comparison of island arc's andesites in terms of petrochemical data is exa- mined. It is definitely established that only two main factors exist controlling the petroche- mical variety of the Kurile arc's andesites.Ori final multivariate statistical technique and computer software are used to extract these fac- tors. It is shown as well that the chemical com- position of igneous rocks depends on the type and structure of the Earth's crust. The follo- ~cing interpretation is proposed for the two factors describing petrochemistry of andesites: the first one is the depth to the Benioff seis- mofocal zone and the second one is supposed to indicate the position of the peripheral magma chambers. The basic trends of variations in the chemical composition components depending on the changes in the controlling factors are de- Tcnnined.

Jan 1, 1987

By Gerry Roblesky

"IntroductionWestar Mining Ltd. is Canada's largest producer of metallurgical coal for the export market. It currently operates two mines, the Balmer Mine at Sparwood, British Columbia producing 6 000 000 tonnes per year and the Greenhills operation at Elkford, producing 2 100000 tonnes per year. Approximately 1600 people are employed between the two mines which operate independently but share common administrative services.Like most mining companies in Canada over the past three or four years, Westar has faced rising production costs along with flat or declining prices and demand for its products. In order to survive under these conditions it has become necessary to strive for decreased costs in any way possible. Over the past two years there has been a widespread introduction of microcomputers across the company. In order to satisfy increasing demand for accurate and pertinent information while at the same time increasing productivity, the microcomputer has become an invaluable tool.This paper describes some of the problems faced by a mine maintenance department in this operating climate and how they were solved with the help of a microcomputer. It also describes some of the problems that may be encountered both with equipment and people and recommends some ways that these might be minimized or avoided. Finally, an assessment of whether or not the move to microcomputers was a current and economical one, and a brief description of future plans and projects is given.The Maintenance OrganizationIn order to appreciate fully the role that microcomputers are playing within the Maintenance Department at Westar Mining, a little background on the organization and operating philosophies is in order. Most of the comments apply directly to the Balmer operations, however, the Greenhills operation is similar in concept.The mine maintenance organization operates on a fleet based concept with these departments reporting to the maintenance superintendent: haulage trucks, shovels and drills, loaders and Caterpillar equipment, maintenance services, and rebuild services.Each of these departments is headed by an assistant superintendent and is responsible for all maintenance on the equipment on the respective fleet. Shift foreman, planners, specialists and clerical staff are assigned to each fleet. A central engineering and administrative group consisting of one engineer and three clerical positions is responsible for maintenance engineering and centralized administrative services"

Jan 1, 1988

By Barry D. Simmons

Abstract -A well-defined approach is essential to ensure the long-term success of a regional exploration program. Teck's approach in eastern Canada is designed to fulfill corporate objectives while recognizing certain unique parameters for exploration in the area. The elements of this approach include clearly defined objectives, technical considerations and personnel policies, all of which are equally important. The goal is a significant discovery before the mid-1990s and the company is confident that this target will be achieved.

Jan 1, 1992

By Hitendrabhai S. Dewangan, Dr. Aashish A. Mehta

Pile foundation is widely used in construction of marine structures. In offshore & marine piling work, drilling/boring supporting fluid is used to stabilize the borehole (excavation) prior to tremie concrete. The poly-fluid is a synthetic drilling granular polymer characterized by high molecular weight.it is mainly used for the preparation of stabilizing and lubrication mud in drilling of deep foundations. Disposal of polymers after using it into the sea, pollutant the sea environment, which may be harmful for living organisms inside sea. To reduce the pollution in offshore/Onshore, it is essential to take the precautions during flushing operation with proper recycled, reused & it’s Disposal. To provide economic and environmental solutions, used slurry was treated with addition dose of fresh material/polymers. The amount of fresh materials/ Polymer to be added can be decided based on (viscosity, density and pH value) test results. Finally, initiate water flow and air agitation as required. Run the tests on the re generated slurry before transferring to storage tank. Also, after storage, polymers will be reused for next operation. Moreover, mud wastage coming from borehole will also be disposed at suitable dumping places.

Sep 1, 2022

By T. H. Aldrich

(Chattanooga Meeting, October, 1908.) Tars paper is intended only to give a preliminary account of experiments made, and conclusions reached, concerning the treatment of certain refractory low-grade gold-ores, the profitable reduction of which may furnish a useful guide to the solution of similar mining and metallurgical problems, not only in the gold-bearing belt of the Southern United States, but perhaps in other regions also. It must be regarded as simply a ?report of progress," preceding a more elaborate and conclusive report of regular practice. The mines of the Hillabee Gold Mining Co. are located upon what is generally known locally as Hog Mountain, on the northern edge of Tallapoosa county, Ala., about 15 miles from Goodwater and 14 miles from Alexander City, stations on the Central of Georgia Railway. Gold has been known since 1839 to exist on this property, where it was discovered in that year by a man named Johnston. The property was worked for placer-gold by the old miners, and there are now the remains of four attempts to operate it by stamp-mill and plate-amalgamation. The present owners purchased it in 1896, and since that time they have experimented at frequent intervals, in order to devise a process that would satisfactorily recover the gold. In 1903 regular operations were begun. Geologically, the mountain consists of an intrusion of what has been pronounced true granite in altered sedimentary slates. The cooling of the granite produced shrinkage-cracks, which have become veins. There is considerable question as to the period of the slate formation; but it is undoubtedly, in my opinion, of Carboniferous age. The veins, about 50 in number, strike N. 60° to 80° E.; dip approximately 65° from the horizontal; vary from a few inches to 25 ft. (being in gen-

Nov 1, 1908

By R. H. Sweetser

AT the Buffalo meeting in October, 1898 (Trans., xxviii., 865), our Secretary, Dr. Raymond, in speaking of the obstacles he had encountered in securing contributions to the Transactions from members in practice, said: "It is the disinclination of many members to communicate incomplete or partial or preliminary results. They are going to write, ' some day,' a thorough and monumental paper; and meanwhile they prefer to communicate nothing. . . . It is the difficulty to which I have just referred that I have encountered in a wide correspondence with members, undertaken for the purpose of securing contributions of fact and opinion concerning the special subject of this discussion. . . . Almost none of them seem to recognize the value of preliminary, incomplete and indecisive reports of practice, as laying the foundation for a thorough inquiry." This remark was made in immediate reference to a discussion concerning blast-furnace tuyeres ; but, notwithstanding this appeal from the Secretary, little has been recorded regarding the distribution, the penetration, and the pressure of the blast at the tuyeres and inside the iron blast-furnace. I am therefore encouraged to contribute the following incomplete and crude observations of the blast-pressure inside the hearth. At the suggestion of J. H. Frantz, the General Manager of the Columbus Iron & Steel Co., a test was made at the East furnace of the company to determine whether there was any difference in blast-pressure at the different tuyeres. The apparatus used for this test was not sensitive enough to give accurate results. It consisted of a small pressure-gauge mounted on a 3/8-in. gas-pipe. A hollow plug, fitting into the peep-hole of the tuyere-cap, prevented the blast from blowing-out during the test. The test-pipe was held in place by means of the handle on the outer end.

Mar 1, 1909

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 Xudong Liu, Feng Chen, Yufeng Guo, Wei Chen, Tao Jiang

Willemite is typically found in oxidized zinc ores and metallurgical secondary resources but without effective extraction method yet. Based on the ideas of zinc phase reconstruction in the willemite, the extraction of zinc from willemite by calcified-roasting using CaO as additive and ammonia-leaching process was studied in this paper. The influences of CaO dosage, roasting temperature, roasting time on the phase transformation and zinc leaching rate were studied, which were characterized by XRD. The results indicated that Zn2SiO4 was transformed into ZnO or Zn2CaSi2O7 .After roasted with 1.4 times of theoretical CaO dosage at l280 for 40 minutes, willemite was thoroughly transformed into ZnO. The zinc leaching rate of the roasted sample was 97.45% in NH4Cl-NH3 H2O leaching system, which increased by 91.40 % compared with zinc leaching rate of 6.05% when willemite was directly leached in NH4Cl-NH3 H2O system.

Jan 1, 2016

By Robert Kimutis, Ke Yang, Yi Luo, Jianwei Cheng

"Surface subsidence processes, especially those associated with a longwall mining operations, could cause operational and/or safety problems to railroads. For railroads with normal amounts of traffic, both the limited time window between traffic and the limited space available make the efforts to return the railroad back to its original state nearly impossible. In order to ensure the safe operation of a subsiding railway, the partial lifting method has been developed and applied. This paper describes the principle and application of the method. A case of applying this method to mitigate subsidence effects on a long section of railway has been demonstrated.INTRODUCTIONMaintaining an operational railway as it is experiencing a longwall subsidence process is not an easy task. The subsidence process may induce sufficient strain and curvature to cause problems to the railroad structures. Localized subsidence-induced slope often is significantly larger than the permissible ruling gradient of 0.7% for a locomotive to haul a loaded train reliably. In order to ensure safe operation, it would be ideal to instantly lift the railroad track back to its original level as it is subsiding. However, it is often impractical to do so due to the limited time windows available between railway traffic and the available space on the railroad base.A partial lifting method has been developed to keep the railroad operational under such limitations. The subsiding railroad track is raised by only a determined, partial amount of the occurred subsidence at a given time. By making such a determined adjustment, the railroad track can be maintained on a smooth and operational profile, and the high strain and curvature on the railroad structures can be reduced as well. To define a smooth railroad track profile in a subsided section the following two conditions should be met: (1) the maximum railroad gradient should be less than the permissible ruling gradient, and (2) the recommended amount of adjustment should be able to be made by the repair crew within the available time windows between scheduled railway traffic.The subsidence effects on a long section of railroad over two longwall panels have been successfully mitigated using the partial lifting method. The railroad experienced a maximum subsidence 89 of about 5 .0 ft (1.5 m) with the average subsidence along the entire length being about 3.45 ft (1.05 m). However, the average adjustment due to lifting that was made along the entire length of the subsidence-influenced railway was only 0.5 ft (152 mm)."

Jan 1, 2010

By Adriaan de Villiers

Many conventional structural analysis and design methods in current use are not appropriate for the mining industry. Two major reasons for this are that: • The economic life of a particular mine is limited, and • Much of the equipment and machinery used by the mining industry operates at relatively low speeds. Both of these factors can have significant cost implications if they are not properly accounted for during plant design. In particular, the often used practice of mitigating excessive vibration by adding mass to machinery supports is not only expensive but may worsen the vibration effects. Some of these problems, such as increased wear and tear, are not always easy to trace back to inappropriate design. This article focuses on vibration related issues and demonstrates that the mining sector has unique problems requiring unique solutions. Vibration: the basics Historic developments leading to current vibration design practices provide the key to why such practices are often inappropriate for the mining industry. To understand this, it is necessary to introduce some basic vibration theory. Consider a simply supported beam or foundation on which a vibrating machine is mounted. For analysis of the system's dynamic response, it may be viewed as a mass attached to a spring and a damper, such as the shock absorber of a car.

Jan 1, 1992

By Sebastian Schmuck, Petrico von Schweinichen, Dieter Senk, Mohammad Peymandar

"At Department of Ferrous Metallurgy of the RWTH Aachen University in Germany steels in the system Fe-Mn-C(-Al) are investigated and produced in the framework of the SFB 761 ""steel-ab initio"". A new world of steel grades leads to special challenges regarding the production and recycling at the end-of-life cycle of product. In order to recycle high manganese steel alloys the EAF has to be chosen preferentially. A good slag practice is necessary avoiding loss of manganese content during melting in the EAF. This paper investigates on the reaction kinetics at the interface of slag and steel containing Mn (17-22 wt.-%) and up to 3 wt.-% Al. The effect of changes in the composition of slag and steel on the interfacial reaction kinetics is studied. The thermodynamic software FactSage™ is utilized to calculate the composition of slag and steel at equilibrium.IntroductionTRIP and TWIP steels are highly alloyed steels which show superior strength and ductility when compared to standard carbon steel and stainless steel alloys. These TRIP- and TWIPsteel grades contain typically 15-30 wt.-% manganese, 0-4 wt.-% silicon and aluminum, and up to 1 wt.-% carbon. Steels containing 18-28 wt.-% manganese and 0.7-1.2 wt.-% carbon together with aluminum addition from 3 to 12 wt. -% and without silicon refer to TRIPLEX high manganese steel alloys. These alloys combine high strength at even large ductility [ 1-4]. At the Department of Ferrous Metallurgy (IEHK) of the RWTH Aachen University in Germany, steels in the system Fe-Mn-C(-Al) is under investigation at the collaborative research center, SFB 761 ""Steel-ab initio"". In this project, high manganese alloyed TRIP and TWIP steels are in the focus.The mechanical properties such as high strength and high ductility make this kind of steels perfect candidates for impact absorption applications in auto body such as vehicle doors and bumpers [2, 5]. With increasing the use of TRIP-, TWIP- and TRIPLEX-steels more high manganese steel scraps will be available at the end of life cycle of products, which need to develop the technologies and metallurgical processes to recovery of high manganese steel. A new steel grade brings new challenges in recycling. In order to recycle high manganese steel scraps the electric arc furnaces (EAF) have to be chosen preferentially [1]. Nevertheless it's not easy to prevent the manganese loss during the process in EAF. During the oxygen refining of high manganese molten steel in EAF the manganese content decreases strongly by oxidation and vaporization, which is affected by slag composition, slag properties such as basicity and viscosity, slag weight as well as melt temperature [6-8]."

Jan 1, 2014

By H. X. Yan, J. X. Zhang, F. S. Niu

"The analysis on influencing factors of hydraulic conditions in fine hematite flocculation, such as stirring speed, stirring time and axial distance of particle size and fractal dimension of floc was investigated. Furthermore, response surface methodology(RSM) has been applied according to the Box-Benhnken center-united experimental design principle to optimize parameters of hydraulic conditions as a response index to indicate the fractal dimension of floc. The results show that when the agitation speed is 900r/min, the axial distance is 2.0cm, and the stirring time is 3.0min, the particle size reaches the maximum value of 35.44µm and the fractal dimension is 1.6594. The interaction between the axial distance and the stirring speed is highly significant, but the interaction with the stirring time is not obvious. The experimental data and model predications match well, which indicates that the established model has high accuracy and practicability. INTRODUCTION With the exhaustion of iron ore resources that are easy to be mined and the vigorous demand for iron and steel, the exploitation and utilization of fine-grained embedded iron ore resources have drawn attention from the industry and the government [1~2]. Flocculation flotation is one of the effective methods for separation and recovery of fine granular minerals. In 1975, the method was first applied and succeeded in Tilden Concentrator, USA. Flocculation and desliming became the key technology of the Tilden to raise its annual treatment capacity from 4 million tons to 8 million tons at that time [3 ~ 4]. In 2008, the selective flocculation and desliming-reverse flotation technology was successfully used to treat 2.8 million tons of Qidong iron ore. Under the conditions of 28.36% raw iron grade and 98% grinding fineness -0.038 mm, the ideal index of 62.5% iron concentrate grade and 68% recovery was obtained [5]. Dr Kitchenner of the Royal College of Mining and the Ore Processing Research Group of Wallenstein Laboratory first proposed the use of flocculation to separate minerals. After that, many scholars conducted a great deal of theoretical and practical researches, but mostly they focused on chemical theories, mathematical models and selectivity differences in the flocculation process, while the research on the influence of the pulp flow state on the separation effect in the flocculation process started later [6~9]. The results show that the motion of the agitated flow field has a significant influence on the formation of flocs. The fluid morphology will change with the change of hydraulic conditions. The change of fluid morphology will not only affect the movement behavior of particles, but also change the action of chemical agents on the surface of mineral particles[10~12]."

Jan 1, 2018

By Gordon Clark, Basar Arioglu, Zlatanic. Sanja, Nasri Munfah, Togan. Tolga

"The 13.2 m external diameter double deck Istanbul Strait Road Tube Crossing is one of the most challenging underwater tunnel projects in the world. Subjected to 11 bars of hydrostatic pressure, variable geology, and being in a very active seismic area, the execution of the project required innovative solutions, sophisticated construction techniques, and prudent risk management approach. The 5 km tunnel consists of 3.4 km TBM bored tunnel, 1 km twin NATM tunnels, and cut and cover sections. The project is being delivered in a Build-Operate-Transfer (BOT) contract in a public-private partnership. The technical challenges, coupled with financial and commercial risks required the implementation of sophisticated risk management tactics including the provision of Independent Design Verification. Presently, the project is in its advanced stages of construction with a recent successful TBM breakthrough on August 22nd 2015. The paper presents the technical challenges of the project from the design, construction, and risk management aspects and provides the status of the construction. PROJECT BACKGROUND The $1.245 billion Istanbul Strait Road Tunnel Crossing project, dubbed the Eurasia Tunnel, is one of several major infrastructure projects being implemented in the Republic of Turkey in a public-private partnership approach. The project provides a direct and easy connection between the Anatolian (Asian) side of Istanbul and the heart of its historical district on the European side across the Bosphorus Strait which connects the Black Sea with the Sea of Marmara. Upon its completion in 2017, the project will improve connections to a wide network of motorways on both sides, increase capacity across the Bosphorus by 100,000 vehicles a day, reduce congestion and save motorists an average of 45 minutes of commuting time in each direction, and bringing significant economic benefits to the city and the region; it will ease traffic across the strait, reduce congestion, decrease pollutants and emission while maintaining the historical silhouette of the city. Figure 1 provides a general view of the project location and alignment. The overall project consists of three parts totaling 14.6km. Parts 1 and 3 consist mainly of widening existing motorways, providing connections to existing roads, reconstructing local bridges and underpasses on the European and Anatolian sides respectively. Part 2 is the tunnel crossing across the Bosphorus; it is the most complex part of the project with the greatest challenges and risks. Part 2 is 5.4 km long consisting of 3.4 km of 13.2m external diameter TBM bored tunnel under the Bosphorus Strait, 1-km of twin NATM tunnels on the Asian side, cut and cover transition boxes in the Asian and the European sides and depressed approaches on both sides. In addition, this segment includes the toll plazas, ventilation buildings, and the tunnel control and maintenance facilities."

Jan 1, 2016

By Peter J. Tarkoy

A great deal of attention has been directed toward the complexities and inadequacies of exploration and pre-bid geotechnical information for heavy construction projects, differing site conditions, and the adversary relationships which generally develop as a result. The adversary position has been maintained at all cost. The solution is simple, if not easy. The solution requires strict and equal adherence to given principles by all parties involved, throughout the life of the project, from conception to completion. It is necessary to review and redefine some basic concepts, without value judgements, from a context of getting the job done. In a recreated context, the role of truth, judgement, responsibility, and integrity, in exploration, engineering design, construction estimating, and project construction, will be examined. It is suggested that anticipated geotechnical conditions be defined unconditionally. The alternative choice is to give the bidder the opportunity of making the interpretive judgements based on geotechnical data. Similarly, a unilateral method of establishing encountered conditions that are agreeable to both owner and contractor, must be outlined prior to contracting. As anticipated and encountered conditions are firmly and accurately established, significant differences can evaluated based upon limitations specified in the contract documents. Impact of differences on project costs can be fixed by pre-defined methods.

Jan 1, 1983

By Robert E. Hershey

1. This investigation shows that the most important beds in Claiborne County, from the standpoint of present production and reserves, are the Coal Creek and Jellico. Together, they contain 69 percent of the known recoverable reserves in the county. Reserves in five other beds are tabulated in this report; in order of quantity of reserves, they are: Blue Gem, Lower Pioneer, Pewee, Big Mary, and Rex. 2. Known measured and indicated reserves in all beds, based on a minimum thickness of 14 inches and on 1,800 short tons per acre-foot of coal in place, are estimated to be 60 million tons, as of January 1, 1953. Of this total, 55 million tons is in beds 28 inches and more thick. Areas in each bed were omitted from the estimate because available data relative to the bed characteristics are too meager to permit making an estimate that conforms with the definitions of measured and indicated coal adopted for this study. Should future drilling or development prove reserves in these areas, such reserves should be added to the total estimated reserves.

Jan 1, 1956

The state of sampling practice in South African minerals industry must be appreciated in the context of the changes that the country has recently lived through. These include the entrepreneurship and investment in local mineral developments, the 'unbundling of mineral assets', the rising foreign control of South Africa's mineral assets, developments in the regulatory environment, and the training that has come to the industry through international experts. In terms of their financial contribution the five most important commodities in the South African mining industry include gold, platinum, non-ferrous metals, ferrous metals, and coal. International Organization for Standardization (ISO) standards form the basis for international trade in two of these commodities and have had a steadying influence on sampling practice over the years. The contribution of the minerals industry to the economic well-being of South Africa and the strong financial links between good sampling practice and minerals marketing, has acted as a driver for improved sampling practice. The state of sampling practice at mining operations of the five main commodities was found to be quite widely divergent with 'pockets of sampling excellence' in each of the commodities. The stages of mineral development at mines for each of the commodities have been described in terms of the sampling sites, sampling mechanisms, and associated problems at different stages of mineral production from exploration, through face sampling, blasthole sampling, and in-mine grade control, ore processing and handling, metallurgical subsampling, process subsampling, and subsampling in the laboratory. In each case the principal errors were identified and their potential impact on value erosion was estimated. In the final analysis it is evident that the greatest problems arise in the early stage of mineral development, and that ferrous metals and coal are particularly susceptible to loss of value through poor sampling practice. Several examples of value lost through poor sampling at the marketing stage that arise from breaching contract specifications, either in terms of grade or sizing, are described. The conclusion is that larger companies with larger ore deposits and greater human, financial, and capital resources are probably more compliant with 'best sampling practice' than smaller companies. Finally the message that equipment suppliers are sending is that business is booming and the awakened awareness of the issues around sampling practice are translating into rands and cents spent on improved sampling equipment.

Mar 1, 2010

By Richard D. Mehring

A refined ad improved self-sealing brattice for use in coal mine rescue and recovery operations for directing the flow of air has been developed and tested by Goodyear Aerospace Corporation for the U.S. Bureau of Mines. The brattice is made from a lightweight, low cost material that meets MSHA flammability requirements. The units can be erected using pins, spade or lightweight extensible poles. Tests here conducted to determine leakage rate from minimal to a maximum of 1.5" H20. The ability to handle reverse flows was demonstrated and a non-flammable foam was used as an auxiliary sealing agent.

Jan 1, 1978