Determining the minimum wall thickness for supercritical CO₂ pipelines requires consideration of multiple factors: internal design pressure, ductile fracture arrest, and dynamic pressure surges. While the design thickness for internal pressure can be readily calculated using ASME B31.4, the impacts of ductile fracture and surge pressures (similar to water hammer in liquid pipelines) are often discussed but seldom addressed in practical wall-thickness calculations.

This article presents practical methods to calculate wall thickness based on ISO 27913 standard to arrest ductile fracture. It also calculates wall thickness under hydraulic shock conditions, drawing on established approaches from Perry’s Chemical Engineers’ Handbook. Together, these methodologies provide engineers with clear, quantitative tools to design CO₂ pipelines that are not only safe and reliable, but also cost-effective.