A steam generator that was running in a company's boiler room exploded. The upper sealing plate of the steam generator was opened and separated from the sealing plates on both sides and the upper tube plate. The overflowing steam caused the collapse of two surrounding walls.
was entrusted by the court to conduct an appraisal and analysis on whether the steam generator involved in the case had quality problems that caused the explosion.
identification and analysis results: The
identification and analysis expert group discussed the relevant information and on-site investigation of the steam generator involved in the case and made a comprehensive quality and technical analysis, and made the following suggestions and conclusions:
1, the nominal material of the explosive steam generator is Q245R. The analysis results show that: the manganese element and aluminum element content are slightly low, the sulfur element content is slightly high, and the other element contents are normal.
2, the base material structure of this explosive steam generator is ferrite + pearlite, and there is no obvious abnormality in the structure.
3. The maximum deformation point of this explosion is the first crack. The inner fillet weld is not welded, and only the outer fillet weld serves as a connection. There is a welding defect here, and the effective thickness is about 2mm. Cracks propagate at the welding defects, resulting in insufficient effective wall thickness. Under the action of internal pressure in the steam generator, a one-time rapid cleavage fracture occurs.
Therefore, the cause of the accident was analyzed to be that a welding defect inside the steam generator product caused the equipment to explode. The nature of the accident was a general production safety liability accident.
