Radiography of Welds Using Selenium 75, Ir 192 and X-rays

The selection and use of any method to be used for radiography depends on a number of considerations, these in general being: a) The size, shape, orientation and distribution of imperfection in the weld. b) The dimensions, geometry and physical properties of the weld and material. c) The radiographic sensitivity required by the Standard, Code or Specification. d) Cost of radiography. e) The location where the radiography will be carried out. f) When Se 75 can be used to replace X-ray. Radiography is suitable for the detection of volume-type flaws. Under assured circumstances it is also suitable for the detection of lack of fusion, cracks and crack-like planar flaws which are oriented in the direction of the radiation beam; however, however it needs to be remembered that the ability of radiography to detect such planar flaws diminishes with unfavourable orientation. The successful use of radiography depends on the ability of the radiation source, be it x-ray or gamma, to provide sufficient radiation to penetrate the material and produce an image of acceptable contrast and definition on the processed radiographic film, using an acceptable and economic time. This paper presents the results of various techniques used on selected samples. These samples used contained a variety of flaws. The samples were subjected to radiographic inspection using X-rays, Ir 192 and Se 75 and the use of different classes of film.