Low-temperature induced brittle fracture: theories and limitations of the previous model.
Low-temperature induced brittle failure scenario.
A review of the extant literature indicates that low-temperature-induced brittle failure (LTBF) is one of the main causes of concern for pipeline operators (Mahgerefteh & Atti, 2006, p. 1248; Andrews et al., 2010,p.277). This is due to the hazardous nature of accidents related to ruptured pipelines that expose these companies to unwarranted negligence fines (imposed by governments and regulatory bodies) due to the casualties as well as environmental damages that results as a consequence of the accidental ruptures (Barlas, 1999, p.6).
The scenario and mechanism involved in the initiation and propagation of low-temperature-induced brittle failure have been a subject of discussion in a variety of literature and studies. The work of Andrews et al., (2010) for instance presented an elaborate discussion on the specific failure scenario that leads to low-temperature-induced brittle failure. The work noted that an alarm has been raised over the observation that leaks in Carbon Dioxide Pipelines could systematically escalate to a serious case of propagating fracture. This, they noted, is due to the extremely large drop in temperature that is linked to the expansion of either dense-phase or gaseous CO2 to the normal ambient conditions. There is a suggestion that such cooling would inherently result in the lowering of pipeline wall temperature to a degree that brittle fracture would take place proceeded by a propagating fracture. Such a failure mechanism is noted by Andrews et al., (2010) to naturally occur in most natural gas pipeline systems but an escalation in the level of concern exists of CO2 pipelines due to the various thermodynamic behaviors of the pipeline's content. The concern is mostly as a result of the complex nature of CO2 dense-phase transport.