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50 Cards in this Set
- Front
- Back
Elements that are pulsed in groups with pre-calculated time delays for each element |
Phased Array (Uses multi-element (array) probes for increased beam, steering, and focusing. |
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What are the two basic types of Beams? |
1. Linear/ Electronic 2. Sectorial/ Azimuthal |
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What beam type has multiple sound beams created at the same refracted angle? |
Linear/ Electronic |
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Most Phased Array inspections are done how? |
Unfocused |
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What beam type creates sound beams through a range of angles by changing the time delay between each of them? |
Sectorial/ Azimuthal |
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The OmniScan collects 10-bit data but is only able to display what amount? |
8-bit data |
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Raising the points Qty. will better or worsen the on screen resolution? (160/ 320/ 640) |
Better |
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What is VPA? |
Virtual Probe Aperature # of elements x pitch |
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5L16-9.6x10-A1-P-2.5-OM, has what mHz frequency? |
5 MHz |
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SA1-N55S-IHC-AOD8, has what refracted angle? |
55' in mild steel. |
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What is Snells law used to find? Sin0 = Vi Sin0 = Vr |
the refracted angle of a sound beam |
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What are the programmed pattern of times delays applied to pulsing and receiving from the individual elements of an array probe in order to steer and/ or focus the resulting sound beam and echo response? |
Focal Laws |
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What Linear array is used in class and the most commonly used? |
1D Linear Array |
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Is Beam formation caused by Constructive or Destructive Interferences? |
Constructive (they match each other and create larger wave) compliment one another |
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Is sensitivity increased or decreased by the addition of more elements? |
Increased with increased energy and the greater the depth of coverage. |
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'Dampening' is done to improve what? |
Resolution, stopping the crystals from ringing at a specific time. |
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Where does focusing and beam steering occur? |
Near Field |
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By increasing the number of elements what do you do to 'resolution'? |
Improve, Narrow beamse equate to better resolution. |
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Aperature refers to what? |
The amount of elements used |
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By altering the time delays of the probe you can successfully do what |
Beam steering |
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The smaller the element sizes and pitches, makes it easier/ harder to beam steer? |
Easier |
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By using the probe outside of its limits what can appear on the screen? |
'Grating Lobes', which could give off false indications or mask smaller ones |
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If you reduce pitch and element size, are Grading Lobes increase or decrease? |
Decrease |
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Concentrating the sound to a point by converging acoustic energy onto a small focal spot is... |
Beam Focusing |
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Using more elements to create the beams creates a smaller/ tighter... |
Focal point |
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By combining Beam Steering and Beam Focusing you can create a ' ' focus |
Angled |
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How do you calculate the Number of Laws (VPA's) |
Total elements- Aperature size+ 1 |
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Which two calibrations should be performed prior to daily use at a minimum. |
1) Wedge Delay 2) Sensitivity |
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What is the angle tolerance on a Beam Angle Verification? |
+/- 2' |
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On the machine what is color directly linked to |
Amplitude return |
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What axis does the A-Scan consist of? |
Ultrasound axis vs. Amplitude axis |
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What axis does the B-Scan consist of?
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Ultrasound axis vs. scan axis |
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What axis does the S-Scan consist of?
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Ultrasound axis vs. index axis |
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What axis does the C-Scan (0' or linear angle) consist of?
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Index axis vs. scan axis |
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What axis does the C-Scan (S-Scan) consist of?
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Focal Law vs. Scan axis |
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The primary use of which scan in weld inspection is the length sizing and verifying scan quality |
C-Scan |
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Manual scanning applicatinos are mostly restricted to which scans? |
A and S scan imaging views |
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Shear wave 'evaluation' should be performed using this display layout? |
A-Scan S-scan and B-scan |
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This scan represents ultrasonic data down the entire scan axis for 'one' focal law or A-Scan only? |
B-Scan |
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270' 0' 180' 90' Does 90' represent Upstream or Downstream. |
Upstream and always the negative side of joint 270' is Downstream |
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What are the two types of encoding? |
Time Based Wheel encoder |
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The Encoder should be calibrated to what percent of accuracy over a 20" length? |
1% |
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What is the maximum drop-out of the scan area you are allowed to have? |
5% but no more than 2 adjacent 1mm lines |
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Phased Array Probes are dampened at what cycles? |
1/2 to 1 cycles |
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As focusing ability increases, the depth of the field .... |
Decreases |
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Using an OmniScan system with a designation of 16;128, the 128 indicates what? |
the maximum number of elements that can be used |
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The maximum number of elements that can be fired at one time is primarily dependent upon what? |
Based on the number of pulsers in the Phased Array unit |
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Which scan is one set of elements used and different focal laws are applied to steer through a sequence of angles |
Sectorial Scan |
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T/F For equivalent aperatures, as pitch increases, grating lobe will increase? |
True |
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A standing wave produced by the phased array probe is defined as what? |
Grating Lobes |