Ф530 mm×55 mm 45钢液压油缸试压爆裂失效分析

Failure Analysis on Bursting of Ф530 mm×55 mm 45 Steel Hydraulic Cylinder during Hydrostatic Test

为找出45钢液压油缸在水压过程中发生爆裂的原因,分析该液压油缸管的宏观形貌、微观金相组织、扫描电镜照片、能谱及理化性能检验结果。分析结果表明,缸体外表面焊接后未及时进行去应力退火处理或去应力退火不到位而产生的焊接裂纹,是导致缸体在进行水压过程中发生脆性开裂的主要原因。建议严格控制焊接工艺,增加有效的焊后无损检测措施,确保钢管正火态交货。

To find out the causes for the bursting of the 45 steel hydraulic cylinder during hydrostatic test,analyses are conducted on the results of relevant tests as made to the cylinder,including macroscopic analysis,the metallurgical analysis,the SEM analysis,the EDS analysis,and the mechanical and chemical property testing etc.It is identified via the analyses that the main reason for the said busting is the welding cracks which are caused by absence of stress-relief annealing treatment,or insufficient stress-relief annealing treatment.Accordingly it is suggested to take such actions as strict control of the welding process,adding necessary after-welding NDT inspections and ensuring the as-normalized furnishing state of the steel tube.