Radiographic Inspection

Radiographic methods have been used to inspect reforming tubes. However, tight cracks cannot readily be seen unless they are normal to the film. When catalyst is in the tubes, the tight cracks will be harder to find because of the varied film densities and the catalyst edges that are present. It is desirable to remove the catalyst from the tubes, but this is not normally practical or economical when the catalyst is not scheduled for replacement.

Radiographs can show cracks regardless of whether there is catalyst in the tubes. However, radiography may not be as sensitive to initial fissuring and tight cracks as is ultrasonic inspection. If radiographs do show cracks, the cracks can be judged on the basis of how many there are and how wide they appear to be on the radiograph. Normally, dark, wide cracks on a radiograph indicate that the cracks are open to the inside diameter of the tube and that the tube should be replaced