Liquid Penetrant Inspection (LPI)
Excessive application of this can mask small indications during inspection.
What is developer? (Ref: TO 33B-1-1, 2.6.4)
This term refers to the strength of a magnetic field at a given point in a material.
What is flux density? (Ref: TO 33B-1-1, 3.2.1)
This probe type is most sensitive to surface cracks in fastener holes.
What is a bolt-hole probe (rotating probe)? (Ref: TO 33B-1-1, 4.5.2)
This type of ultrasonic transducer focuses sound waves into a smaller area for higher sensitivity.
What is a focused transducer? (Ref: TO 33B-1-1, 5.4.3)
These are the two most common film processing methods.
What are manual and automatic processing? (Ref: TO 33B-1-1, 6.8.1)
The maximum temperature limit for most penetrant systems without special qualification.
What is 125°F (52°C)? (Ref: TO 33B-1-1, 2.3.6)
The best magnetization technique for detecting cracks at 45° to the part surface.
What is multi-directional magnetization? (Ref: TO 33B-1-1, 3.4.7)
Lift-off variations appear on the impedance plane in this general direction.
What is vertically (up/down axis)? (Ref: TO 33B-1-1, 4.4.2)
Grain structure causes this type of interference that limits UT sensitivity in coarse materials.
What is scattering (or noise from attenuation)? (Ref: TO 33B-1-1, 5.3.6)
This material is most often used as a filter to reduce low-energy scatter.
What is lead? (Ref: TO 33B-1-1, 6.7.6)
This type of discontinuity is often missed by LPI
What are too tight or non-surface breaking subsurface cracks (non-surface-breaking defects)? (Ref: TO 33B-1-1, 2.2.2)
This safety hazard increases when using wet fluorescent particles with inadequate ventilation.
What is inhalation/skin absorption of carrier fluids? (Ref: TO 33B-1-1, 3.5.2)
This calibration standard is used to ensure proper depth sizing in eddy current inspections.
What is an EDM notch standard? (Ref: TO 33B-1-1, 4.6.2)
The distance between the transducer face and the first usable back wall echo is called this.
What is the dead zone? (Ref: TO 33B-1-1, 5.6.3)
A radiograph showing excessive density (too dark) was likely caused by this error.
What is overexposure (too much radiation or time)? (Ref: TO 33B-1-1, 6.6.2)
The major disadvantage of using water-washable penetrants versus post-emulsifiable.
What is the higher risk of over-washing and loss of sensitivity? (Ref: TO 33B-1-1, 2.3.3)
The two methods used to verify adequate field strength during MT.
What are pie gauge and quantitative quality indicators (QQIs)? (Ref: TO 33B-1-1, 3.4.9)
Changes in both this property and conductivity can make alloy differentiation possible with ET.
What is permeability? (Ref: TO 33B-1-1, 4.2.2–4.2.3)
In angle-beam inspection, this geometric factor causes variations in path length and sensitivity.
What is beam spread? (Ref: TO 33B-1-1, 5.7.5)
This type of scatter is the dominant radiation interaction above 100 keV.
What is Compton scatter? (Ref: TO 33B-1-1, 6.7.5)
The two most common causes of false penetrant indications.
What are poor cleaning and rough surface finish? (Ref: TO 33B-1-1, 2.5.5)
When using half-wave rectified AC, the magnetic field penetrates deeper than with AC due to this effect.
What is reduced skin effect? (Ref: TO 33B-1-1, 3.2.4)
When inspecting thin materials, signal overlap of both surfaces is called this.
What is through-thickness effect (or double surface effect)? (Ref: TO 33B-1-1, 4.4.5)
The condition when two signals overlap and cause loss of defect resolution.
What is signal interference (or superposition)? (Ref: TO 33B-1-1, 5.6.6)
The specific activity of this isotope makes it ideal for inspecting steel thicknesses up to several inches.
What is Iridium-192? (Ref: TO 33B-1-1, 6.4.3)