6: Inspection Flashcards
What are conducted regularly on UT instruments and transducers?
Performance tests
Who performs a performance test?
A level 2 or third party
Calibrations should be done a minimum of?
Every 2 hours
What are the two types of calibrations?
Time base and sensitivity
What does a time base calibration do?
Ensures material thickness and discontinuity depth are accurately displayed.
What reflectors in stand blocks are used to set reference levels?
Back wall, side drilled holes and FBH/notches
Why don’t you have a back wall reflection with angle beam testing?
When sound hits the surface it reflects away
What signals are shown in the screen in Angle-Beam testing?
Only the IP unless echo is received
How is the V Path calculated?
2T/cos theta
How can the skip distance be calculated?
2T x tan theta
What are the 4 types of scanning movements?
Traversing (perpendicular to weld), lateral (parallel to weld), rotational (spinning probe by axis) and orbital (moving probe around fixed point)
Where should you position the transducer from centre if weld to direct sound to root?
1/2 skip distance
How can surface distance be determined?
Surface distance = sound path x sin theta
How do you set mine depth is discontinuity found in the 1st leg?
Sound path x cos theta
How can the depth be determined if discontinuity found in 2nd leg?
2T - (sound path x cos theta)
