Reference Blocks (2) Flashcards
What do Calibration Blocks do?
Insure reproducibility of results They are controlled: - Flaw free (except reference flaws) - Grain size - Attenuation - Heat-treatment
IIW Block (International Institute of Welding)
Two versions
- has a 25mm (1in) radius
- a square notch
both can be found in metric or imperial dimensions
What does the IIW Block do?
- Calibrate the time base
- Verify linearity of instrument
- Find index point + probe angle
- Verify resolution
- Set sensitivity
ASTM E127 (Alcoa) Blocks
Two types:
- Area Amplitude Series (Same height, diameter of FBH changes)
- Distance Amplitude Series (Different height, same FBH diameter)
Both are made of Aluminium, are 2in in diameter, FBH is drilled 3/4” from bottom.
Identification numbers on ASTM Blocks
0000-0-0000
1st number- material block is made of
2nd number- diameter of the hole (in 64th of an in)
3rd number- distance from top surface to top of FBH (in)
Mini IIW Block
Height and radius of 2in/50mm
- used to calibrate time base
DSC
Small field block
- calibrate time base
- set sensitivity
- shaped like two curvy mountains
DC
Small field block
- calibrate time base
- shaped like half of a tiered circular cake
SC
Small field Block
- calibrate time base
- set sensitivity
- shaped like a rectangle
Miniture angle beam/Kidney/Rompus Block
Small field block
- calibrate time base
- shaped like a curved mountain
Stepwedge
Used for thickness measurements on thin materials
- 4/5 steps
Curved Stepwedge
Used for thickness measurements on thin curved materials
- 4/5 steps
- must be re-calibrated once a year
ASME Block
Draw Distance Amplitude Correction (DAC) curves when inspecting components under the ASME code.
- for thicknesses of 1-2in
- different thickness and curvature to match different components
