The EPRG Recommendations for Crack Arrest Toughness for Line Pipe Steel (Third Edition)

Abstract

The third edition of the EPRG recommendations for crack arrest toughness for line pipe steels is presented. The third edition extends the applicability of the recommendations to pipelines transporting lean natural gas at pressures up to 100 barg (1450 psig), in diameters up to 1422.4 mm (56 inch), in grades up to Grade L555 (API 5L X80), and design factors up to 0.8. A quantitative definition of a lean gas is included in the third edition. The recommendations are intended to be applied to new pipelines. The recommendations are not intended to be applied retrospectively to existing pipelines.

Depressurization and heat transfer during leakage of supercritical CO2 from a pipeline

“…’s 26 experimental and model analysis pointed out that the presence of N 2 presents a new challenge to the development of the decompression wave prediction model. Cosham et al 27 . stated that focusing on the thermodynamic changes caused by impurities is beneficial to designing more safety pipelines.…”

“…Results show that the saturation pressure can change significantly when certain impurities are present, even in small quantities. Gu et al 24 27 stated that focusing on the thermodynamic changes caused by impurities is beneficial to designing more safety pipelines. Thus, it is necessary to fully and clearly understand the depressurization and inner temperature distribution of high-pressure impurities in CO 2 after release or rupture.…”

A machine learning based sensitivity analysis of the GTN damage parameters for dynamic fracture propagation in X70 pipeline steel

“…It is known that the CVN impact test can lead to non-conservative predictions when applied to high-grade steels. In that case, correction factors such as the modified Leis correction [6] should be implemented for each individual case when determining fracture toughness based on CVN-energy [7]. Based on fullscale burst data and lab-scale experiments, empirical fracture arrest criteria such as the wellestablished Battelle Two Curve Method (BTCM) [8] were introduced.…”