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IN THE last three years the wire industry has done considerable production testing with molybdenum disulphide as an additive to their wire drawing and forming lubricants, with the result that by the beginning of 1962 an estimated 70% of the U.S. mills were using molybdenum disulphide (moly) in production. The advantages reported by these mills are increased die life, brighter surface finishes, and improved products principally for the heading and wire rope industries. Other reported improvements by these mills have been higher drawing speeds or reduced force necessary to perform the drawing, less wire breakage, reduced wear on machinery, and a slower hardening rate.

The PROCESS OF MAKING WIRE by drawing operations through dies, as distinct from hammering, though believed to be several thousand years old, until the last century was performed only by man‐, horse‐ or water‐power, so that production was slow and small. These old methods could not meet the greatly increased demand that then arose for wire of all kinds, such as copper wire for electrical purposes, and consequently power‐driven multi‐die benches were developed. Drawing speeds were still limited to several hundreds of feet per minute because of the rapid wear of the chilled iron and steel dies then used; but with the introduction of tungsten carbide dies and diamond dies, speeds were again increased, and now figures of 2,000 ft. per minute for steel wire, and 5,000 ft. per minute or more for copper and aluminium, are commonplace. These advances have required improved drawing lubricants, and future increases in drawing speeds likewise largely depend on improving lubricants still further. The general problem is to provide adequate lubrication for long die life, coupled with the intensive cooling that higher drawing speeds compel.

IT has recently been said by a member of a firm of justly‐famous wire makers (1) that there is probably no finer grade of wire than that designed for aero‐engine valve springs to Air Ministry Specification D.T.D.5A, and despite the fact that this article will deal principally with defects in that wire, the author, from an experience gained from the handling of some hundreds of miles of it, must state at the outset that he can endorse this opinion.

DRAWING of metals occurs in innumerable ways, both hot and cold. Here, however, we are concerned only with the cold drawing operations used to form vast tonnages of steel, and large quantities of non‐ferrous metals, as tube and wire, and for the forming of sheet metals (especially by deep drawing).

Whereas the Minister of Labour (hereafter in this Order referred to as the “Minister”) has received from the Brush and Broom Wages Council (Great Britain) the wages regulation proposals set out in Schedules 1 and 2 hereof;

The function of an internal combustion engine valve spring is to provide sufficient force throughout the engine cycle to maintain the tappet in contact with the cam at all speeds within the engine speed range. However, it must not exert such force that will produce unacceptable contact stresses between tappet and cam. The performance requirements of a valve spring are that it must not fail by fracture or, by load relaxation, lose so much of its controlling force that it fails to maintain control between tappet and cam.

This is a shortened version of the Discussion that took place at Birmingham in January. Part One, which covered Lubricants for the Cold Rolling of Non‐Ferrous Metals and Alloys appeared in our February issue.

NO component of the modern aero and automobile engine has been more uncertain in action and more troublesome in service than the valve spring.

To drive along winding roads from the south‐east shores of Lake Constance not far from where the mighty Rhine enters the lake, passing small rural settlements and isolated chalets as the road weaves its way upwards through patches of woodland, with the landscape clad in the first snow of the season, may savour more of arrival for an early Winter sports holiday than for a company visit. At an altitude of some 700 metres, however, on the outskirts of the village of Wolfhalden, which has a population of about 1,700, Circuit World's destination during late November was the wire weaving plant of G. Bopp & Co. AG, whose head office is located in Zürich.

This paper gives a review of the finite element techniques (FE) applied in the area of material processing. The latest trends in metal forming, non‐metal forming, powder metallurgy and composite material processing are briefly discussed. The range of applications of finite elements on these subjects is extremely wide and cannot be presented in a single paper; therefore the aim of the paper is to give FE researchers/users only an encyclopaedic view of the different possibilities that exist today in the various fields mentioned above. An appendix included at the end of the paper presents a bibliography on finite element applications in material processing for 1994‐1996, where 1,370 references are listed. This bibliography is an updating of the paper written by Brannberg and Mackerle which has been published in Engineering Computations, Vol. 11 No. 5, 1994, pp. 413‐55.