Evaluation of the Effectiveness of Heat Treatment on the Defective Short Pipe of a Gas Field Slug Catcher

For the upper and lower short pipes of a gas field segment flow collector, the types and quantities of defects were determined using magnetic particle, phased array ultrasonic testing, and low-magnification acid etching inspection. Through metallographic analysis and impact testing, it was found that the micro of the short pipes was pearlite ferrite Widmanstätten structure, with generally large grain sizes, uneven distribution of metallographic structures, and oversized-metallic inclusions, leading to a significant decrease in impact toughness and brittle fracture on the fracture surface. After heat treatment verification tests on the forging, themanstätten structure disappeared, the grain size was significantly refined, the metallographic structure distribution became obviously uniform, and the impact performance was greatly improved, and met the standards for forging short pipes and design technical requirements. It was recommended to strictly adhere to standards and technical requirements during the production process of the short pipes, including selecting billets, controlling heat treatment processes, and conducting thorough quality inspections before shipment.