Drawing Board Stage Research Articles

Prediction of electronic equipment reliability

The inherent reliability of the electronic components of a system is the capability of the design to function without failure in the work assigned to it. A prediction at the drawing-board stage of the design of equipment and its reliability can be made.

Corrosion Problems of Ammonium Sulphate Manufacture

In the manufacture of ammonium sulphate, whether by using evaporators or saturators, the erosive effect of crystals present in solution, the low sulphuric acid concentrations usually present, and the relatively high temperatures of operation give rise to serious corrosion problems which begin at the drawing board stage of design and continue through all stages of manufacture. These corrosion problems are discussed in detail in this article and advice is given on materials of construction, including stainless steels, nickel alloys, rubber‐lined mild steel, lead, silicon irons, aluminium and a number of plastics.

Tyre Characteristics as Applicable to Vehicle Stability Problems

The authors define the characteristics of a pneumatic tyre which affect the handling, or stability, of a car, and briefly describe a machine which was developed to measure these characteristics. The results are given of various experiments showing the effect of several factors on the characteristics; the applicability of these results to the behaviour of a tyre on the road is also discussed. Briefly defining oversteer and understeer, the authors outline a proposed method for directly determining the handling performance of a car while it is still in the drawing board stage. It is pointed out that this will only apply to steady conditions and some of the factors affecting transient behaviour are discussed. In particular, the importance of the self-aligning torque is stressed. The problem of breakaway is mentioned and doubts are cast on the applicability of the machine results to high-speed cornering, or racing; the technique of drifting a car round a corner is discussed. The MS. of this paper was received at the Institution on 17th November 1953, and in its revised form on 11th January 1954. For the report of the meeting in London, at which this paper was presented, see p. 134.