Radiograhy Lessons Using the XRSIM Program
One of the education improvement projects completed by the Collaboration for NDT Education involved the introduction of X-ray inspection simulation program into the college classroom. Ten X-ray inspection exercises were developed that make use of an X-ray inspection simulation program developed by the Center for NDE at Iowa State University. The lessons cover the following topics:
Kilovoltage and contrast sensitivity
Milliamperage and time relationships
Creating an exposure chart
Source to film relationships
Radiographic equivalence factors
Defect composition, shape, and size
Defect shape and relationship to X-ray source
Beam divergence and image distortion
Developing a radiographic technique card
The student booklet for the lessons and the program user instructions may be downloaded below. NDT instructors may request a copy of the instructor's booklet by email addressed to NDTfirstname.lastname@example.org. Please include a daytime phone number in the email so that a member of the collaboration for NDT Education may contact you. The instructors booklet is also free of charge. The XRSIM program is commercially available from NDE Technologies, Inc,
More Information on Teaching With the XRSIM Program
Using the XRSIM program, a student must perform all of the operations required to produce a "real" radiograph except that the film-developing step is eliminated. First, the exposure must be set-up by loading in a CAD model of a part, positioning the part relative to the x-ray source and the film, and selecting the x-ray generator and film type. The student must then adjust the generator settings and the exposure time to produce the desired exposure. Once the part set-up and generator setting selections are complete, the program generates a simulated radiograph in only a few seconds compared to twenty or thirty minutes when film developing is involved. The student can view a number of simulated radiographs at once so that side-by-side comparisons are possible. A densitometer feature allows students to collect quantitative information about the images.
One of the main advantages of the program is that it provides a hands-on learning environment were results are produced very quickly. This allows instructors to expose students to a greater number and variety of problems and allows the students to discover the effects of variables for themselves. Quick results also reduce the many distractions unrelated to the primary learning exercise that can confuse the results and even the purpose of the exercise. Another advantage is that results are not complicated by unnecessary variables such as film processing artifacts. The simulator also records all the variables used to produce images, which allows instructor to quickly trouble shoot any problems that students may be having with an exercise.
Since the program uses a CAD model and does not require a real part, inspections can be simulated that would be impossible or too costly to develop outside of the computer environment. Flaws of various shapes and sizes can be easily introduced into the CAD model to produce a sample set for probability of detection exercises. Use of the program is more cost effective because students can make all the usual mistakes while learning the basics of radiography, and correct them before actual exposing film. In addition to reducing consumable costs, the use of the simulator could reduce equipment costs since the students will spend less time using expensive x-ray systems.