ISSN: 1945-7553
Page Count: 3

An Extensometer for Circumferential Strains

Findley, WN
Professor of engineering and technical assistant, Division of Engineering, Brown University, Providence,R.I.

Reed, RM
Professor of engineering and technical assistant, Division of Engineering, Brown University, Providence,R.I.

Abstract

An instrument is described for measuring circumferential strains in plastic specimens of circular cross section. It consists of four direct-current differential transformers (DCDTs) suitably mounted on an invar ring. The DCDTs probe the position of the surface of the specimen at opposite ends of two mutually perpendicular diameters. Examples of performance are given for creep of a thin-walled tube of polyurethane.

Keywords:
extensometers, strains, plastics, creep, circumferential strain, differential transformers

Paper ID: JTE10659J
DOI: 10.1520/JTE10659J
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