AS 1330-1974

Covers the determination of the percentage shear area as a measure of toughness of plain carbon and low alloy steels in resisting the propagating of fractures over the temperature range where the fracture mode changes from brittle to ductile.

This standard describes the method for conducting a dropweight tear test of carbon steel, low alloy steel, and similar materials up to 20 mm thickness. In particular it is intended for line-pipe, or plate intended for line-pipe, 300 mm diameter or greater, and excludes the testing of weld metal. The test is identified as DWTT.NOTE: Difficulty may be experienced in applying this test to material below 5 mm thickness.This test can be used to determine the appearance of propagating fractures in plain carbon or low alloy pipe steels (yield stress less than 800 MPa) over the temperature range where the fracture mode changes from brittle (cleavage or flat) to ductile (shear or oblique).The test can serve the following purposes:(a) For research and development, to study the effect of metallurgical variables such as composition or heat treatment, or of fabricating operations on the mode of fracture propagation.(b) For evaluation of materials for service, to indicate the suitability of materials for service applications by indicating fracture propagation behaviour at the service temperature(s).(c) For information or specification purposes, to provide a manufacturing quality control technique when suitable correlations have been established with service behaviour.

Reconfirmed 1989