Research And Development Of Automatic Ultrasonic Inspection System For Pipeline Weld Of Nuclear Power Station Penetrating Parts

As a clean energy source,nuclear power is widely used all over the world,and the importance of nuclear safety is also increasing.Regular NDT of civilian nuclear safety equipment is an effective measure to ensure the safety of nuclear equipment,among which ultrasonic testing is one of the most widely used volume testing methods.Ultrasound testing has been implemented in the design,manufacture and operation stages of nuclear power components.In this paper,a non-destructive testing system based on ultrasonic testing is developed for the joints of main steam pipeline and main water supply pipeline in nuclear island wall.Firstly,this paper summarizes the development of nuclear power in the world,the research status of pipeline ultrasonic testing equipment,testing methods and simulation technology at home and abroad.Analyses the size of pipeline weld size and environment of nuclear power plant penetration pipeline.Secondly,aiming at the special weld position and thick wall of the pipeline,an automatic detection system is innovatively designed,including system structure design,load analysis,electrical control system design,coupling circulation system design and mockup design.Thirdly,the optimal coupling pressure of the probe frame is measured by experimental method,and the stress of the key components of the gear ring and pin shaft is analyzed by FEM to verify the rationality of the system design,and the kinematics parameters are obtained by the kinematics simulation of the system.Finally,according to the requirements of the inspection specifications and the inspection experience,the parameters of the probe are selected,and the sound field simulation and defect detection capability simulation are carried out by using CIVA simulation software to determine the parameters of the probe,and the field application is carried out to verify the effectiveness of the system.The main innovations of this paper are as follows:1.According to the special environment of the object to be inspected,the characteristics of the object to be inspected are analyzed,and an automatic detection system suitable for the object to be inspected is innovatively designed.2.Based on the experimental method,the optimum coupling pressure of the probe is determined and the optimum cylinder pressure is calculated.Through static modeling,the stress parameters of the gear ring and supporting structure are obtained,and then the strength of key components is analyzed by FEM software to verify the rationality of the design.Kinematics simulation of the system is carried out based on Pro/Engineer software,and the end trajectory curve and motion parameters are obtained.3.Preliminary selection of ultrasonic probe based on standards and experience,simulation of acoustic field of probe based on CIVA software,and selection of probe parameters that can cover the full depth of the detected object.