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By H. J. N. Winhoff

The tailings dam at Consolidated Murchison Limited by H. J. N. WINHOFF, Ing. Grad. (Visitor) The history of tailings dam operations at Consolidated Murchison Limited is briefly recounted, and a mechanical method of dam-wall construction is described and illustrated in some detail.

Jan 12, 1973

By C. L. de Jongh

Fracturing of the rock caused considerable difficulties during the boring of a deep-level tunnel in hard rock. A pilot bore was suggested as a possible means of reducing the effect of the fracturing, and this possibility was investigated theoretically by means of a three-dimensional elastic stress analysis. Failure criteria were applied to the results of this analysis, and it was found that fractures predicted by the use of a simple criterion of limiting tensile macrostrain criterion agreed remarkably well with in situ observation. It was concluded that fracture could not be avoided and that a pilot bore was likely to aggravate tunnelling conditions.

Jan 1, 1978

By D. A. Fenton

The structural design of large grinding mills, with reference to shell-mounted bearings by D. A. FENTON*, P. Eng. (Visitor) The paper outlines the advantages of shell-mounted grinding mills over mills having a conventional trunnionsupported shell. The growing use of larger mills in the past decade has led to a significant number of mechanical and structural failures, the most common being those at the junction of the head and the shell. Larger mill diameters favour the use of shell-mounted bearings. The elimination of castings, which have an inherent weakness to fracture, makes the shell-supported mill lighter and stronger than a conventional mill of the same shell thickness.

Jan 9, 1976

By N. M. Holford, R. G. Moore

A strong and determined character, Theodore Carl August Meyer had a very firm approach to people whose opinions or conclusions differed from his own, but this trait was leavened by touches of startlingly original ideas and enthusiasm that certainly produced effective results from his subordinates.

Jan 1, 1980

By S. Curry

The Objana Cement Plant is located in central Nigeria, approximately 200km south of capital city Abuja (figure 1). It is the second largest cement plant in Africa, and the fifth largest in the world [1]. The selected mining location is unique as it has all the major raw materials (except gypsum) in close proximity. This includes limestone, clay, marl, laterite soil, and laterite iron. [ ] The plant has a capacity of 5 million metric tones per year (~15,000 tones per day). A 135 megawatt gas-fired power plant, with 90 km of natural gas pipeline, was constructed to power the plant. The total project cost is approximately 1.2 billion US dollars. The lifeline of the plant is two overland conveys totalling 7.7km in length. The first 800m conveyor is relatively mundane. The second conveyor however, is unlike any other troughed belt conveyor in the world. It 6.9km length transports 2,400 T/H and operates at 5.0 m/s. Its ?snake? profile consists of 11 vertical cuvees, and four horizontal curves. The last of which is 2,000m in radius, has a length of 2.2km, and is located at the high tension head end of the conveyor. Although these specifications are noteworthy, the unique feature of this system is that it is entirely elevated from head to tail using a triangulated truss gantry structure (figure 2).

Jan 1, 2008

By A. M. Sage

This paper reviews the metallurgical functions of vanadium in high-strength Iow-alloy steels, and discusses the ways in which vanadium is used in various types of steel supplied as reinforcing bars, plates, sections, and strip. Potential developments to meet new engineering requirements are discussed briefly.

Jan 1, 1984

Minerals Handbook 1994-95: Statistics and analyses et the world's minerals industry? by P. Crowsons, Basingstoke, Macmillan, 1994 ISBN 0 333 60931 X. £85. Available from Macmillan Direct Ltd., Houndmills, Basingstoke, Hants, RG21 2XS, UK. Review prepared by Theo J. Oosthuizen, Information and Educational Programmes Division, Mintek

Jan 1, 1995

By N. Gibson

The application of oxygen in a copper smelter by N. GIBSON* (Visitor) This paper describes how the problem of increasing the capacity of the Rokana copper smelter was handled, and how oxygen was found to be technically and economically the best solution. The first phase of its implementation is outlined.

Jan 3, 1974

By R. H. O?Connor, B. N. Soutar

The paper reviews the introduction 01mechanical shaft drilling into the sinking 01shafts in the Gold Fields Group. A comparison is made between the operating costs 01the drilling rig and those of conventional hand-held machines, and it is concluded that, despite certain disadvantages, mechanical drilling is preferable.

Jan 1, 1988

Prof C T O'Connor holds the degrees of BSc, BSc Hons, University of Cape Town (UCT), where he started his academic Lecturer in the Department of Physical Chemistry in 1976. Mr P Smith, educated in England and the former Southern Rhodesia, joined Gold Fields of South Africa in 1966 as a Metallurgical Learner Official. After obtaining a BSc Eng at the University of the Witwatersrand in 1972, he returned to Gold Fields. Mr P D K Robinson was born in Zimbabwe, and was educated at Dale College in Kingwilliamstown, matriculating in 1952. He holds a Mine Surveyor's Certificate obtained in 1961) and a Mine Manager's Certificate (obtained in 1966), as well as an EDP from the University of the Witwatersrand.

Jan 1, 1991

Mr R. w.o. Kersten joined the Geological Department of Anglovaal in 1964 after obtaining a B.Sc. Honours degree in Geology at the University of Pretoria. Mr H.G. Mosenthal was educated at Pretoria Boys' High School and the University of the Witwatersrand. He holds a B.Sc. in Mining Engineering and a GDE.

Jan 1, 1985

Book review Doyle, William S. Strip Mining of Coal; Environmental solutions. Park Ridge (New Jersey), 1976. 352 pp. $32. Surface mining of coal is still in its infancy in South Africa. The environmental repercussions following large-scale disturbance of the land surface, and the secondary effects of the disposal of waste products and effluents from mining, have not yet become apparent.

Jan 1, 1977

By P. J. D. Lloyd

This fascinating paper deserves study by all who are interested in the economics of gold production. The argument in the paper that price is determined by the balance between supply and demand may be thought to be obvious. However, correlation analysis presumes causality, and there is some evidence in the paper to suggest that causality is absent in this market.

Jan 1, 1984

By A. A. Oakes, P. M. C. Wilson

This paper describes some aspects of the planning of a new colliery which commenced production in the Middleburg district in 1966. An account is given of some of the problems encountered in the early years of operation and of what was done to solve them. The conclusion is reached that design of plant and machinery should be flexible to permit multiplication of units.

Dr c. J. Fauconnier, Pr. Eng., has a D. Eng. from the University of Pretoria, an M.RA. from the University of Oregon, and an M.Sc. (Eng.) and B.8c. (Min. Eng.) from the University of Pretoria. Dr B. K. Loveday obtained a degree in Chemical Engineering at the University of Natal, where he also obtained a Ph.D. in the kinetics of froth flotation.

Jan 1, 1983

The finite element method of stress analysis is nowadays widely used in the fields of mining, mechanical and civil engineering. This paper presents a short description of the three-dimensional method, in which the elements used are arbitrary hexahedrons. Two examples of the application of the method are presented, namely, calculation of the elastic stress distributions in a coal pillar and in an opencast mine.

By J. D. Flint

A description is given of the extraction of pillars in a seam of coal which normally varies in thickness from 10 feet to 14 feet using conventional trackless mechanised units. By using the pocket and fender method of pillar extraction, the high capital cost of hydraulic supports is eliminated, and a volumetric extraction of 85% to 90% of the seam of coal is possible. This method of mining opens up the possibility of extracting vast tonnages of coal which hitherto would have been left in situ as pillars. The major benefits likely to accrue from this technique are seen as follows: 1. Greater volumetric extraction of the seam; 2. Longer panel life with less frequent transferring of sections; 3. Preservation of our natural resources. The authors deal with the history of this development at Springfield Colliery, discuss the present results and outline the future trends in the light of current experience.

Mining plants operating in dunes north of Richards Bay have uncovered Iron Age archaeological material that spans the greater part of the past 2000 years. This was announced by archaeologists Gavin Whitelaw of the Natal Museum's Institute of Cultural Resource Management (ICRM), and Len van Schalkwyk and Mlungisi Ngubane of the KwaZulu Monuments Council (KMC), who are currently contracted by Richards Bay Minerals (RBM) to assess the cultural resources exposed during mining activities.

Jan 1, 1995

By A. Vogelzang

The paper describes how the level of the water-table was reduced as a result of increased pumping of water from the mine. Because such a condition in an area where there is compactable material above solid dolomite results In surface movement, steps were taken to restore the water-table to its former level. These included the return of water underground via a sinkhole and boreholes, and the piping of water from another mine.

Jan 1, 1978

Bowen, R., and Gunatilaka, A. Copper, its Geology and economics. London, Applied Science Publishers, 1977. Miller, D. S. Internal flow systems. (Volume 4 in the BHRA Fluid Engineering Series). 1978. 288 pp. £21,50. MACH 80 The Machine Tool Trades Association of Great Britain (M.T.T.A.) announce that MACH 80 - The International Machine Tool Exhibition - will take place from Tuesday, 22nd April, to Friday, 2nd May, 1980, at the National Exhibition Centre, Birmingham.

Jan 1, 1979