ISSN: 1945-7553
CODEN: JTEVAB
Page Count: 12

Direct Measurement of Displacement in Instrumented Charpy Impact Testing for Structural Integrity Assessment

Tronskar, JP
Det Norske Veritas Pte. Ltd.,

Mannan, MA
National University of Singapore,

Lai, MO
National University of Singapore,

(Received 10 August 2000; accepted 19 January 2001)

Abstract

The present research aims to develop a method for the direct measurement of load-line displacement during instrumented Charpy impact tests. The method involves direct measurement of the load-line displacement using a laser interferometer in addition to the load-line displacement derived from the load signal by double integration according to standard procedures. The ISO striker edge is instrumented with a piezoelectric sensor and the system is calibrated in situ in the impact tester as recommended by ISO 14556:2000 Steel Charpy V-notch Pendulum Impact Test—Instrumented Test Method, using a 0.5% accuracy reference load cell and a hydraulic jack system.

Introductory tests were conducted using fatigue precracked and V-notched specimens in the temperature range + 23 to −80°C on a conventional ship grade steel NVE36 for application in floating production, storage, and off-loading (FPSO) vessels. The results were promising and good correlation was obtained with results from conventional instrumented impact testing where the load-line displacement was calculated by double integration of the force versus time plot.

Keywords:
steel, instrumented impact testing, direct measurement of load-line displacement, dynamic crack resistance curves, dynamic yield strength

Paper ID: JTE12252J
DOI: 10.1520/JTE12252J
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