Strength of thick cylinders subjected to repeated internal pressure 1

Abstract

In April 1956 the authors presented to the Institution of Mechanical Engineers a paper entitled “Fatigue under Triaxial Stress: Development of a Testing Machine and Preliminary Results”, and in September 1956 a supplementary paper was presented at the International Conference on Fatigue of Metals. In these papers the authors reported tests carried out on cylinders made from a $2\phantom{\mathrm{(}}1\mathrm{/}\phantom{\mathrm{(}}2$ per cent. nickel-chromium-molybdenum steel, which were subjected to (up to) 10 million repetitions of internal oil pressure of (up to) 20 ton/in². Since these papers were published a considerable amount of testing has been carried out on cylinders made from a mild steel, a 3 per cent. chromium steel, an austenitic stainless steel, a light alloy, a nearly pure titanium, the nickel-chromium-molybdenum steel in a harder state, and both the nickel-chromium-molybdenum steel and the chromium steel in the nitrided condition. In addition, tests or more academic significance have been carried out on the nickle-chromium-molybdenum steel in an attempt to achieve a better understanding of the extraordinary results which have been obtained.

The present paper is concerned mainly with the presentation of results (supported, of course, by ancillary tests on each material) which are of importance in design. Points of academic interest are discussed only when they are relevant to the practical problem. To make the paper reasonably self-contained, a brief summary of the previous work has been given.