在役石油平台用压力容器超声导波检测

Ultrasonic Guided Wave Testing of Pressure Vessels Working in Oil Flat

超声换能器发射波在容器壁形成的超声导波可在涂层或其他覆盖物下沿容器壁传播,可以检测出容器腐蚀形成的缺陷及其内部缺陷,实现在役容器的快速检测。采用ISONIC2005超声检测系统,针对海洋石油钻井平台压力容器,利用模拟仿真和试验测试相结合方法,采用自行研制的超声导波换能器,制定相应的导波检测规范进行检测。检测结果表明,导波频率1.5 MHz,压电陶瓷晶片尺寸23 mm×28 mm,入射角为53°时,有效检测距探头1 000 mm处的6 mm×1.25 mm的平底孔信号,在实际在役石油平台容器检测中,探测距离长度不大于500 mm时,可以有效检测出带表面漆层和内部液体压力容器内外壁腐蚀类缺陷,超声导波检测结果与实际腐蚀减薄量相一致。

The ultrasonic guided wave from ultrasonic transducer can transmit along the pressure vessel surlace under coating, so it can be used to detect the corrosion defects and other defects in the pressure vessels. The ISONIC2005 ultrasonic testing system with a designed ultrasonic transducer was used to test pressure vessels in oil flat based on established detecting procedure. Simulation experiments and practical testing were carried out. The results show that 5 mm × 1.25 mm man-made hole 1 000 mm away from the probe can be effectively detected with the ultrasonic frequency of 1.5 MHz, piezoelectric ceramic crystal plate of 23 mm ×28 mm, and ultrasonic wave angle of incidence of 53° During detecting in-service oil flat pressure vessels, if the detecting distance is not bigger than 500 mm, the corrosion defects at the outer wall of the pressure vessels with paint and inner liquid can be detected. The practical corrosion depth is consistent to the detecting result.