OmniScan MX2 Training ProgramPhased Array Amplitude Analysis 2 . Using side drilled holes (SDH) or notches of different size at different depths a reference sensitivity can be calibrated for comparison to detected flaws during the inspection. corrosion mapping. Modifying the gate position in analysis mode will convert 10 bit data to 8 bit data where only 0-100% amplitude is available. In other words. Typically to 80%. the more gain required resulting in a more sensitive inspection and greater potential for a reject. The MX2 uses an 8 bit amplitude resolution (0-100%) for the digitized A-scan and a 10 bit resolution (0-200%) for the C-scan gate data and gate readings. and composite inspections.OmniScan MX2 Training – Amplitude Analysis Overview The majority of both conventional and phased array weld inspections can be considered “Amplitude based” inspections as opposed to time of flight applications like TOFD. when you change the gate position all data between 101-200% is converted to 100% amplitude. The smaller the notch or SDH. Amplitude analysis is dependent on the data having been acquired in accordance with the calibration and inspection rules specified in the referencing code or procedure. The A% reading is available for either the maximum peak (E as pictured below) or first peak (D as below) detected in the gate as configured in Gate\Alarm>Gates>Parameters>Mode>Peak Selection. 3 . The % amplitude reading is available for both gate A (Red) or gate B (Green).OmniScan MX2 Training – Amplitude Analysis – A% Readings The A% reading is the peak amplitude detected in gate A. but when it flashes red\white as pictured it indicates that at least one element in the current focal law is saturated.OmniScan MX2 Training – Amplitude Analysis – A% Readings cont. Gate A in the A-scan display is normally red. 4 . The gate B reading is 33. In the example below readings have been selected for both gate A% and gate B%.7%. The reading for gate A of 86.5% also indicates with a red background that at least one focal law in the group is saturated. In the below example of inadequate penetration the reference sensitivity was calibrated to 80% amplitude using a notch in a piping calibration block. (UT>Advanced>Reference Amplitude>Typically 80%) This reading is available for both gate A (AdBCurve) and gate B (BdBCurve).8% amplitude signal in gate A is 1.9 dB over the reference sensitivity of 80%. A negative number would indicate below the reference curve.OmniScan MX2 Training – Amplitude Analysis – AdBCurve Reading The AdBCurve reading calculates the difference between the peak amplitude signal in gate A and the sizing curve level. The AdBCurve reading indicates that the 99. 5 . 6 .8 dB.8 dB (Ref sensitivity) – 3. The AdBr reading indicates that the 144% amplitude signal in gate A is 4. (UT>Advanced>Reference Amplitude>On) This reading is available for both gate A (AdBr) and gate B (BdBr).0 dB (Scan sensitivity) = 4. In the below example of inadequate penetration the reference sensitivity calibrated for 80% at 18.2 dB. 26 dB (AdBr) – 18.2 dB over the reference sensitivity of 80%.OmniScan MX2 Training – Amplitude Analysis – AdBr Reading The AdBr reading calculates the difference between the peak amplitude signal in gate A and the reference. 8 dB over the gate A threshold of 10%.9% amplitude.9% amplitude signal in gate A is 17.OmniScan MX2 Training – Amplitude Analysis – AdBB Reading The AdBA reading calculates the difference between the peak amplitude signal in gate A and the gate threshold level. In the below example slag is detected in gate A at 77. 7 . (Gate\Alarm>Gate>Position>Threshold>40%) This reading is available for both gate A (AdBA) and gate B (BdBB). The AdBA reading indicates that the 77. OmniScan MX2 Training – Amplitude Analysis – %(U(r)) Reading The %(U(r)) reading displays the amplitude of the signal at the position of the reference cursor on the UT axis This reading is available for both the red reference cursor %(U(r)) and the green measure cursor %(U(m)) on the UT axis. The signal amplitude at the position of the reference cursor on the UT axis is 71. 8 . In the below example porosity is detected in gate A.4% amplitude. A short stroke of the envelope function key will clear the current envelope.OmniScan MX2 Training – Amplitude Analysis – A-scan Envelope The green amplitude envelope trace is useful for optimizing and peaking signals for both calibration and sizing. 9 . The envelope will refresh automatically when the current A-scan or focal law is changed. A long stroke of the envelope function key will enable or disable it on the A-scan. the amplitude C-scan is defined by the vertical focal law axis and the horizontal scan axis. probe movement) For each focal law. (Focal laws 45-70 vs. Scan Axis (Probe movement) 10 . The primary function of the amplitude Cscan for weld inspection is data screening and flaw length sizing. 1 pixel = 1 A-scan. the pixel color is determined by the peak amplitude signal in gate A for that position on the scan axis.OmniScan MX2 Training – Amplitude Analysis – Amplitude C-scan Focal laws 45-70 For the S-scan weld inspection. >80% >80% Is this a flaw or is it geometry? Is this an embedded or ID\OD connected flaw? Where in the weld volume does this flaw occur? Where to excavate to repair the flaw? Without visualizing the S-scan or relative 55. Only amplitude. volumetric location or depth of the flaw. 11 .5 degree A-scan at 269mm it is not possible to know the flaw type.OmniScan MX2 Training – Amplitude Analysis – Amplitude C-scan cont. and scan axis position are known in the uncorrected amplitude C-scan data view. In the amplitude C-scan below. the data point circled represents the maximum signal detected in gate A by the 55.5 degree focal law at 269mm on the scan axis. 5 degrees at 269mm on the scan axis) One is a geometric reflector from the weld crown and one is rejectable side wall lack of fusion. (55. In the S-scans below are two indications that will produce the exact same pixel color in the C-scan. ? OD weld crown geometry (2) 1 2 Side wall lack of fusion (1) 1 2 ? 12 1 2 1 2 . Because both signal 1 and 2 are detected in gate A.OmniScan MX2 Training – Amplitude Analysis – Amplitude C-scan cont. it is not possible to differentiate between them without use of the S-scan or A-scan. 13 .OmniScan MX2 Training – Amplitude Analysis – Amplitude C-scan cont. By visualizing the S-scan and A-scan that generated the amplitude C-scan pixel at 269mm it is obvious that the indication is a geometric reflector from the far side weld crown and need not be evaluated as a flaw. 14 . By visualizing the S-scan and A-scan that generated the amplitude C-scan pixel at 173mm it is obvious that the indication is SWLF and must be evaluated as a flaw.OmniScan MX2 Training – Amplitude Analysis – Amplitude C-scan cont. The primary indicator for flaw type characterization is the flaw’s volumetric location. lnk .Free Download Manager.
Comments
Report "MX2 Training Program 14B Phased Array Analysis-Amplitude"