Views:7 Author:Site Editor Publish Time: 2020-01-10 Origin:Site
The difference of “examining” and “scanning”in ultrasonic flaw detector“examine”and ”scanning ”are two common easily to understand terms,but writer thinks:there are some questions we should discuss .The definition of examining is move probe and makes sound beam covered volume of workpiece that needed to be tested.This description is almost the same as follows。In ASMEVSE1316 section 12 has followed definition:examining --probe does relative movement on sample,so as to check whole volume of material.This definition is right for normal UT;but is not suitable for phased array probe ,because when probe doesn’t do relative movement on samples ,by phased each crystal,it can also make sound beam does relative movement with tested samples--examining
《nondestructive testing term ultrasonic flaw detection》 has followed definition:the planed movement between sound beam and tested samples,should not include the movement of sound beam on direction of propagation;the planed movement between sound beam and tested samples should be understood as relative change between sound beam and tested sample;the above definition ,including relative movement between sound beam and probe,such as S type examining of phased array.
The writer thinks GB/T12604.1-2005 regarding to definition of examining is correct。Because if move probe on sample,is called examine,not forward move probe ,keep sound beam in cross section,and do extended phased examining ,is also called examine.Such as phased array E examine and S examine. 2 The definition of scanning.
The definition of Scanning,section 12 in ASME V SE1316 has followed definition :scanning --electron beam cross cathode ray oscilloscope and repeat to move uniformly.
Original meaning of Scanning means electron beam moves in display .ultrasonic testing quote this term,mainly used to mean image formed by moving track of electron beam in display ,because these images are display of ultrasonic testing results.
For phased array ultrasonic sound beam relative to probe angle deflection ,it should be called “sector examine” or “sector scanning”? Normal ultrasonic regarding to definition of “scanning ”,is still suitable?This question refers to examine and scanning ,and relationship between them。Such as definition of GB/T12604.1-2005,”examine ” means sound beam moves relative to workpiece or probe;and “scanning”means electron beam moves in display.So sound beam relative to probe angle deflection is called “sector examine”.4 the relationship of “examine”and “scanning“ like above described，and have difference,but very closely connected.examine is the base of scanning,is the source of scanning signal;scanning is display of examining。Phased array ultrasonic sector examine,is always correspond to “sector scanning”.This probably the reasons that the two terms are confused in some information.