IQI Selection & Radiographic Sensitivity Flashcards

For a double-wall single-image (DWSI) technique, the IQI thickness designation is selected based on which thickness?

Answer: The nominal single-wall thickness of the wall being evaluated

In DWSI technique, the IQI is selected based on the single-wall thickness being evaluated (typically the far wall), not the total two-wall path thickness.

When radiographing a carbon steel weld, which IQI material should be selected?

Answer: Steel IQI of radiographically similar composition to the test material

The IQI must be fabricated from the same material group as the test object so that its X-ray absorption properties accurately represent the sensitivity achieved in the actual material.

What is the primary purpose of a step-wedge calibration film used in conjunction with radiographic examination?

Answer: To verify film density levels and confirm consistent film processing conditions

Step-wedge calibration films verify that film density and processing are within acceptable limits, ensuring consistent film quality independent of the IQI sensitivity function.

According to ASME Section V, what radiographic sensitivity level is typically required for pressure vessel weld examination?

Answer: 2% sensitivity (2T essential hole must be visible)

ASME Section V requires 2% sensitivity, meaning the 2T essential hole in the IQI appropriate for the material thickness must be clearly visible on the radiograph.

An IQI with a designation number of 10 has what nominal thickness?

Answer: 0.010 inches

Hole-type IQI designation numbers directly represent the IQI nominal thickness in thousandths of an inch; designation 10 equals 0.010 inches (10 thousandths).

Where must the IQI be positioned relative to the weld during radiographic examination?

Answer: On or adjacent to the weld within the area of interest being examined

The IQI must be placed on or directly adjacent to the weld within the area of interest so that it reflects the actual radiographic sensitivity being achieved in the examination zone.

What is the purpose of having three holes (1T, 2T, and 4T) on a standard hole-type IQI?

Answer: To provide multiple sensitivity reference levels, allowing verification at different degrees of detectability

The three holes (1T, 2T, 4T) represent progressively larger diameters, each corresponding to a different sensitivity level, so code requirements can specify which hole must be visible to establish the accepted sensitivity threshold.