If welded parts with different thickness cannot be rendered with adequate contrast on a single film, what should be done?

If welded parts with different thickness cannot be rendered with adequate contrast on a single film, what should be done?

• A. Two films may be used with different exposure times
• B. Increase the exposure on the single film
• C. Use a lower contrast film
• D. Remove one plate and weld with uniform thickness

Answer: (A)

When radiographic testing a weld with varying thickness, the amount the X-ray is attenuated depends on the local thickness. A single film exposed to cover both thick and thin areas often can’t show adequate contrast everywhere because thick regions need more exposure to reveal details, while thin regions can become overexposed. Using two films with different exposure times allows you tailor the exposure to each thickness region, so both areas display defects clearly without compromising one another. This keeps the test true to the actual joint geometry. Increasing exposure on one film would help the thicker portion but would over-penetrate or wash out features in the thinner area, reducing overall usefulness. A lower contrast film reduces the ability to distinguish defect indications across varying densities. Removing one plate to weld with uniform thickness changes the part being inspected and isn’t a valid or practical solution for evaluating the real weld.

When radiographic testing a weld with varying thickness, the amount the X-ray is attenuated depends on the local thickness. A single film exposed to cover both thick and thin areas often can’t show adequate contrast everywhere because thick regions need more exposure to reveal details, while thin regions can become overexposed. Using two films with different exposure times allows you tailor the exposure to each thickness region, so both areas display defects clearly without compromising one another. This keeps the test true to the actual joint geometry.

Increasing exposure on one film would help the thicker portion but would over-penetrate or wash out features in the thinner area, reducing overall usefulness. A lower contrast film reduces the ability to distinguish defect indications across varying densities. Removing one plate to weld with uniform thickness changes the part being inspected and isn’t a valid or practical solution for evaluating the real weld.