Fracture Propagation Control (Stage 1)

Core Participants:
                                CRC Head Office
                                University of Adelaide
                                Australia Pipeline Industry Association
                                BlueScope Steel

Project Summary:
Ensuring adequate resistance to longitudinal, shear fractures in natural gas pipelines is a fundamental requirement of gas transmission system design.  The Australian pipeline industry, in a major conference ("Fracture Control in Gas Pipelines", Sydney 1997), concluded that there was a significant need to conduct full scale burst tests of relevance to current and future operations.  The project therefore seeks to define a specification for the conduct of a series of fracture propagation tests. It is envisaged that these tests would provide the basis for developing new data and validating the empirical correlations which ensure the continuing performance, integrity and safety of Australian pipelines.

Stage 1 of this project will establish the test specification required for a series of pipeline crack arrest tests. This specification will be used to determine the test methodology, a test geometry and an approximate cost per test. These will be presented to industry for consideration. Should Stage 2 of the project be approved, this stage is envisaged to include the conduct of an initial series of tests.  The crack arrest tests advocated above provide two major potential benefits to the pipeline industry: 1) The current uncertainty over the efficacy of fracture arrest design methods for Australian pipelines can be removed; 2) Avoids the cost of "overspecification" such as the use of margins of safety above the calculated arrest toughness, and the use of crack arrestors when they may not be necessary.