Petrochemical forgings are key components in petrochemical production, and their quality and reliability are crucial to the safety and efficiency of the entire production process. However, in the manufacturing process of forgings, due to the influence of various factors, the forgings may have various defects, such as cracks, pores, inclusions and so on. These defects will cause the performance of the forging to decline, and even lead to safety accidents. Therefore, defect detection and repair has become an important part of quality control of petrochemical forgings. This paper will discuss the defect detection and repair technology of petrochemical forgings, in order to provide useful reference for related enterprises and research institutions.
Common forging defects and detection methods
Cracks: Cracks are one of the most common defects in forging, which can be caused by the temperature gradient during forging, stress concentration, or problems with the material itself. The commonly used crack detection methods include ultrasonic detection, magnetic particle detection and liquid penetration detection. These methods can detect cracks on the forging surface as well as cracks near the surface.
Pores: Pores are formed because the gas is not completely discharged during the forging process. The porosity will reduce the density of forgings and affect their mechanical properties. The commonly used stomatal detection methods include X-ray detection and ultrasonic detection.
Inclusion: Inclusion is caused by foreign bodies entering the forging during the forging process. Inclusion can lead to uneven mechanical properties of forgings, increasing the risk of stress concentration and crack propagation. The commonly used inclusions detection methods include metallographic detection and ultrasonic detection.
Defect repair technique
Welding repair: For defects such as cracks and pores, welding repair technology can be used to repair. Welding repair can compensate for defects by filling materials to restore the integrity and mechanical properties of the forgings. Common welding methods include arc welding, laser welding and plasma welding. In the process of welding repair, it is necessary to select the appropriate welding materials and process parameters to ensure the welding quality and repair effect.
Machining repair: For minor surface defects, such as scratches and uneven bumps, machining repair technology can be used to repair them. Machining repair can restore the surface quality and appearance of the forging by removing the surface defect layer. Common machining methods include grinding, polishing and shot peening. In the process of machining repair, it is necessary to choose the appropriate machining tools and process parameters to avoid further damage to the forging.
Heat treatment repair: For the defects such as cracks and deformation caused by temperature gradient or stress concentration in the forging process, heat treatment repair technology can be used to repair them. Heat treatment repair can eliminate or reduce the impact of defects by changing the structure and stress state of the forging. Common heat treatment methods include annealing, normalizing and quenching. In the process of heat treatment repair, it is necessary to develop the appropriate heat treatment process and parameters to ensure the repair effect and the performance of the forging.
Composite material repair: For complex defects or large area damage, composite material repair technology can be used to repair. Composite repair can enhance and restore the mechanical properties of forgings by pasting or impregnating composite materials on the damaged area. Commonly used composite materials include carbon fiber composite materials, glass fiber composite materials, etc. In the process of composite repair, it is necessary to choose the appropriate composite materials and process methods to ensure the repair effect and the bonding strength of composite materials and forgings.
The defect detection and repair technology of petrochemical forgings is an important link to ensure the quality and reliability of forgings. The defects such as cracks, pores and inclusions in forgings can be detected effectively by means of ultrasonic detection, X-ray detection and metallographic detection. By using welding repair, machining repair, heat treatment repair and composite material repair technology, defects can be effectively repaired to restore the integrity and mechanical properties of the forging. In the future, with the continuous development of non-destructive testing technology, additive manufacturing technology and artificial intelligence technology, the defect detection and repair technology of petrochemical forgings will become more efficient and intelligent to provide a strong guarantee for the development of the petrochemical industry.
