输油管道改输气管道止裂性能研究现状
Research Status of Crack Arrest Performance of Oil Pipeline Converted to Gas Pipeline

随着我国天然气需求上升及“双碳”目标的推进，将输油管道改建为输气管道成为节约成本、优化管网的重要途径。本文围绕输油改输气中的关键问题展开研究：首先分析改输需注意的问题，包括掌握原管道基本情况、管材适用性评价、脆性断裂控制、止裂性能检验(如夏比冲击试验)及剩余强度评估；其次综述国内外止裂性能研究进展，涉及X80/X90管线钢裂纹扩展模拟、巴特尔双曲线法(BTCM)、流固耦合模型(如ABAQUS有限元分析)等，重点探讨裂纹尖端张开角(CTOA)、裂纹扩展速度与减压波速的耦合关系；最后阐述改输具体步骤(清洗、内检测、管材更换、设备改造、试压干燥等)，并结合濮临管道、双–魏管道、克–乌复线等国内成功案例，验证改输方案的可行性与安全性。这项研究为改进油气输送管道的工程实践提供了理论依据和技术指导。
With the rising demand for natural gas in China and the promotion of the “double carbon” goal, converting oil pipelines into gas pipelines has become a crucial approach to save costs, optimize pipeline networks, and improve resource utilization. This paper focuses on key issues in such conversions: First, it analyzes critical considerations, including understanding the basic conditions of the original pipeline, evaluating the applicability of pipe materials, controlling brittle fracture, testing crack arrest performance (e.g., Charpy impact tests), and assessing residual strength. Second, it reviews domestic and international research progress on crack arrest performance, covering topics such as crack propagation simulation for X80/X90 pipeline steel, the Battelle Two Curve Model (BTCM), and fluid-structure interaction models (e.g., ABAQUS finite element analysis), with a focus on the coupling relationship between the crack tip opening angle (CTOA), crack propagation speed, and decompression wave speed. Finally, it outlines specific conversion steps (cleaning, in-line inspection, pipe replacement, equipment modification, pressure testing, and drying) and validates the feasibility and safety of the conversion through successful domestic cases, such as the Pulin Pipeline, Shuang-Wei Pipeline, and Ke-Wu DN529 Oil Pipeline. The study provides theoretical support and technical references for the engineering practice of converting oil pipelines to gas pipelines.