Calculate a radiographic technique for the circumferential steel butt weld of a pipe of outer diameter, 250mm and wall thickness 20mm. The total unsharpness for a radiographic technique is 0.2828mm. The film unsharpness is 0.2mm.  The X-ray instrument to be used has a focal spot size of 3 mm(=s) and a maximum tube current of 5mA. A density of 2 is required on the “MX” film to be used. Use 300kV and use the exposure chart in Figure 1.

Figure 1X-ray exposure chart. Film type: MX, film density 2, thin lead screens, source to film distance, sfd, 1000 mm. 

The specimen in Figure 1 is x-rayed with the direction of the x-rays being directed vertically through the specimen as shown.

Figure 1 Cross sectional view of a steel plate containing 2 rectangular shaped defects A and B, made by machined slots 

Is this defect detectable? Give the reason why it is or is not detectable.

The main advantage of having small focal spot on an X ray tube is:

The selection of the proper source-to-film distance is a primary factor in controlling:

If the required X ray exposure time for a 225 kV, 5 mA exposure is 3 minutes, approximately what exposure time would be required at 10 mA?

An advantage of a larger grain film is:

Which of the following is classified as electromagnetic radiation?

An advantage of a gamma ray source is:

For radiography inspection, an effect of scattered radiation is to:

Thicker materials would normally be inspected using: