2.1 Nonlinear Factors in Fluid Pipes Nonlinearity in dynamic systems is a relative concept that depends on both the physical nature of the problem and the choice of coordinate system. For example, a circular arc appears linear in polar coordinates but nonlinear in Cartesian coordinates. Similarly, if curvature is...

Abstract: Slender fluid-conveying pipes are widely used in critical engineering systems, including engine hydraulic circuits, aviation refueling equipment, nuclear heat exchangers, and offshore drilling platforms. At high flow velocities, these pipelines can experience flow-induced instabilities, such as buckling...

Abstract This paper investigates the application of electrolytic desulfurization technology for controlling corrosion in sulfur-containing wastewater pipes used in oil and gas storage and transportation. First, the fundamental principles of electrolytic desulfurization are presented, along with the various types of...

Abstract: This paper analyzes the risks involved in inspecting buried polyethylene (PE) gas pipelines and proposes inspection items based on identified failure modes and potential hazards. The inspection items encompass document review, assessment of pipeline location, orientation, and burial depth, macroscopic inspection,...

Abstract: This article examines the research and intelligent applications of trenchless repair technology for municipal drainage pipelines. After reviewing several common repair technologies, the article analyzes their application process from three key aspects: repair methods, pipeline diversion schemes, and desilting...

1.1 Advanced Welding Technology The development of automatic welding technology of pipes began in 1958, when Price Company in the United States developed the first set of automated welding equipment. In 1969, Kraus Company introduced the CRC welding machine. In 1972, the former Soviet Union developed flash welding...

Abstract: Oil and natural gas are fundamental to ensuring national energy security. Pipeline construction, safe operation, and efficient utilization are at the core of developing oil and gas storage and transportation systems. Welding technology plays a crucial role in ensuring the safety, engineering quality,...

Abstract This study analyzes the causes of surface defects in high-frequency welded pipe billets, specifically, linear indentations and molten metal pits caused by the upper extrusion rollers. To address these issues, the design parameters of the upper extrusion rollers were optimized. By increasing the hole radius of...

Abstract: Plastic pipes are widely used in municipal engineering due to their numerous advantages, including high flexibility, excellent hydraulic performance, ease of installation, and strong corrosion resistance. Their application significantly enhances the quality and safety of municipal projects. Currently, various...

Martensitic stainless steel is widely used in demanding environments, such as oil well pipelines, due to its superior mechanical properties and corrosion resistance. However, its corrosion resistance is influenced by several key factors, including alloy composition, microstructure, and external environmental conditions....

2. Corrosion Mechanism 2.1 CO₂ Corrosion Mechanism 2.1.1 Cathodic Reaction CO₂ dissolves in water to form carbonic acid (H₂CO₃), which dissociates in two steps to produce H⁺, HCO₃⁻, and CO₃²⁻ ions. The corrosion mechanism of CO₂ as a weak acid continues to be an area of active research. In CO₂-containing solutions,...

4. Solid Lubricating Coating Traditional lubricants form a fluid or mixed lubrication film at the friction interface, whereas solid lubricants rely on the material’s low shear properties or transfer film to enhance wear resistance and reduce friction. Solid lubricants are typically applied as powders or coatings...