Development Of The Online Ultrasonic Nondestructive Inspection System For Seamless Tubes

With the rapid development of industry of China, there was a rapid increase on the proportion of the domestic seamless tube production in the globe. If defective seamless tubes were used in some important occasions such as petroleum, chemicals and boiler, it would lead to disastrous consequences. Therefore, lots of attention to seamless tube evaluation has been paid from academia and engineering, and this kind of studies has become a hotspot.Based on the above background, the latest research results in Mechatronics and the research of fieldbus application, online accuracy measurement for wall thickness of seamless tube based on generalized cepstrum, black-box testing, this dissertation targeted the seamless tube quality testing, developed a set of high-performance ultrasonic nondestructive inspection equipment. The main performance of the equipment has reached the level of practical application. This paper focused on:Chapter 1, the basic principles and importance of independent R&D of online ultrasonic inspection system were introduced. The latest research of Ultrasonic detection (UT) at home and abroad was described.Chapter 2, based on the main performance and specification, a general design of the online ultrasonic nondestructive inspection system for transverse, longitudinal, wall thickness flaws detection was completed. The method of fixed ultrasonic transducer array and rotated tube was used in this system.Chapter 3, the general scheme of mechanical system and electrical system was designed. Some of the key technologies of electrical system such as Profibus and CAN(Controller Area Network) was studied.Chapter 4, the online flaw detection and probe arrangement was studied. A kind of technology of wall thickness measurement based on generalized cepstrum was developed, and the experimental results indicated that the proposed method was suitable for the online ultrasonic nondestructive inspection system.Chapter 5, the control program based on LABVIEW of up-lever computer was described. The general scheme of the control program was designed according to the demand analysis. We completed the communication between PC and PLC, and the communication between PCs. The test strategy of the control program was put forward based on black-box testing.Chapter 6, the main work and conclusions of the research was summarized, and the prospect for the further research objects was put forward.