OmniScan SX \ MX2 Training ProgramPhased Array Analysis – Length Sizing Chris Magruder V4.1R3 S(r) – Scan axis measure cursor S(m) Amplitude C-scan Scan axis reference curser S(r) Scan axis measure curser S(m) Focal law data cursor Scan axis data cursor PA Weld.Cursors In a typical weld inspection. – Scan axis reference cursor.Opd .OmniScan SX\MX2 Training – Length Sizing . Use to visualize the A-scan and S-scan at a given data point. flaw length sizing is performed on the weld line represented by the scan axis available on the C-scan and B-scan. The three cursors used for flaw length sizing are: – Data cursor. OmniScan SX\MX2 Training – Length Sizing . – S(m) Position of the measurement cursor on the scan axis.Readings The primary readings associated with flaw length sizing are: – S(r) Position of the reference cursor on the scan axis. the data cursor is positioned on the data point of maximum amplitude of the flaw and the reference and measure cursors are placed on the edges of the flaw. – S(m-r) The delta between the scan axis reference and measurement cursor. S(m-r) S(r) PA Weld.Opd S(m) . In the lack of side wall fusion example below. The flaw starts at 153mm and ends at 186mm for a total length of 32mm. Opd S(m) . Probe size and frequency. Beam focus. Trial and error with destructive testing and up front engineering using EDM notches on welded samples will take into account all aspects of the inspection for length sizing optimization to include: – – – – – – Weld bevel and process. Pipe diameter. a -3 dB to -6 dB drop technique will produce accurate sizing for typical inspections. Inspection resolution.OmniScan SX\MX2 Training – Length Sizing – Example 1 For linear flaws such as side wall lack of fusion and inadequate penetration. S(m-r) S(m-r) S(r) S(r) PA Weld. Scan plan strategy. a dB drop technique is not possible and the extremities are determined from a rapid drop technique on the first and last indication. S(r) CobraA15_One Sided. To the extent an indication is one intermittent flaw or a series of individual flaws to be analyzed independently is determined by the referencing code or procedure.Opd S(m-r) S(m) .OmniScan SX\MX2 Training – Length Sizing – Example 2 For indication such as the intermittent lack of fusion below. the inspection was performed with a scan resolution of .5mm on the scan axis as the probe or scanner is moved.5mm.1mm for flaws measured on the scan axis. This results in a length sizing accuracy of +\.OmniScan SX\MX2 Training – Length Sizing – Inspection Resolution The length sizing accuracy is directly related to the inspection resolution on the scan axis that was entered in >Scan>Area>Scan Resolution.Opd . CobraA15_One Sided. In the example below. Every focal law on every group is recorded at intervals of . S(r) S(m) S(m-r) CobraA15_One Sided. lack of root fusion is measured by a -6 dB drop using the color palette of the C-scan and observing the S-scan and A-scan. The extremities of the flaw were identified at approx.OmniScan SX\MX2 Training – Length Sizing – Example 3 In the example below. 40% amplitude and marked with the scan axis reference and measure cursors.Opd . The maximum amplitude of 84.9% was detected at 66 degrees at 284mm. the encoder has a resolution of 12 steps per mm that results in a minimum resolution of .OmniScan SX\MX2 Training – Length Sizing – Inspection Resolution The smallest number that can be entered into the inspection resolution is dependent on the resolution of the encoder. In the example below.08mm) However most inspections are recorded at a 1mm resolution regardless of encoder. PA_Weld.Opd . (1mm \ 12 steps = .08mm. OmniScan SX\MX2 Training – Length Sizing – Curved Arrays (CCEV) Length sizing accuracy is greatly improved by the use of internally focused curved arrays.2mm C-scan length sizing with internal radius focused probe.4mm . C-scan length sizing with flat probe. S(m-r) = 4. S(m-r) = 2. especially on small diameter piping where the reflected signal is skipping off a small curved spot on the pipe’s inner diameter surface. Both the Olympus Cobra small diameter piping system and Pipe Wizard pipeline girth weld system utilize internally focused curved arrays for improved length sizing accuracy. coverage. Trial and error on test specimens validated a -6dB drop technique for precision length sizing. S(r) S(m) S(m-r) CUNI_A15_. a 1mm X 5mm EDM notch is placed on the OD centerline of a 4 inch diameter CuNi (Copper-nickel) weld to validate detection.OmniScan SX\MX2 Training – Length Sizing – Example 4 In this example.Opd . Centerline 1mm X 5mm OD notch Small diameter length sizing distortion can be overcome by use of laterally focused curved array probes such as the Olympus CCEV A15 probes pictured right. On the scan axis. sizing. and volumetric position. the red reference cursor S(r) is placed on the notch start position and the green measure cursor S(m) is placed at the notch end position. Notch length in S(m-r) = 5mm. -3 dB drop technique. ? ? ? ? . Technique developed from up front engineering on specific weld using specific equipment. 4. -6 dB drop technique.OmniScan SX\MX2 Training – Length Sizing – dB Drop Techniques Question: Which of the below is the preferred method for length sizing weld flaws? 1. 2. 3. Rapid drop technique. Where precision length sizing is required it is best developed by trial and error using EDM notches and embedded flaw test specimens of same weld bevel. weld thickness and bevel. Answer: 4. weld process. ? ? ? ? . etc. Length sizing accuracy is dependent on my factors including pipe or vessel diameter. 4. Technique developed from up front engineering on specific weld using specific equipment. Rapid drop technique. 2. -6 dB drop technique. There is no one technique that will provide accurate length sizing for every weld. 3. type of defect.OmniScan SX\MX2 Training – Length Sizing – dB Drop Techniques cont. -3 dB drop technique. Question: Which of the below is the preferred method for length sizing weld flaws? 1. probe size. frequency and focus. – I(m) Position of the measure cursor on the index axis. – I(m-r) Delta between the reference and measure cursors on the index axis.OmniScan SX\MX2 Training – Length Sizing – Index Axis Measurement Sizing is also available on the index axis with the following cursors: – I(r) Position of the reference cursor on the index axis. I(r) I(m) I(m-r) TF_32EL_HighResNotch.Opd . I(r) I(m) I(m-r) Reference cursors crosshair position Measure cursors crosshair position TF_Manual Inspection12mm. – I*U(m-r) Delta between two cursor crosshair positions.Opd .OmniScan SX\MX2 Training – Length Sizing – Off Axis Measurement Sizing is also available for off axis indications with the following cursors: – Crosshair position of the reference cursor on the index and UT axis. – Crosshair position of the measure cursor on the index and UT axis. This can be done directly on the color palette bar on the right side of the C-scan or in >Display>Properties>Category: Color Palette>Start and >End. .OmniScan SX\MX2 Training – Length Sizing – Example 5 In this example the color palette was manipulated to display a -6 dB drop for length sizing on the scan axis. 6. 2. 4. 1. 9. 7.OmniScan SX\MX2 Training – Length Sizing – Example 5 Because the of the orientation of the planer flaw is perpendicular to the beam. 3. 5. 8. 11.5mm Flaw end on scan axis (Sm): 64.5mm Flaw length (Sm-r): 10mm Flaw depth (DA): Flaw upper extremity (Ur): Flaw lower extremity (Um): Flaw height (Um-r): Flaw type: . a -6 dB drop sizing technique for side wall lack of fusion is very accurate. 10. Flaw max amplitude (A%): Flaw volumetric position: Embedded \ Surface connected?: Flaw start on scan axis (Sr): 54. OmniScan SX\MX2 Training – Depth and Height Sizing – Multigroup Analysis The scan axis cursors are linked for all groups.Opd . When two sided data is available the cursors are positioned on the flaw extremities based on analysis of both groups simultaneously by observing the C-scan and S-scan data for both groups. The flaw start and stop position on the scan axis may be determined from two separate groups Crack stop position on group 1 Crack start position on group 2 TF_2XSEC. OmniScan SX\MX2 Training – Length Sizing – Supplemental TOFD TOFD greatly assists in length sizing accuracy and only uses 1 of the 256 available A-scans possible in the OmniScan. Combining those probe characteristics and the fact the TOFD is not dependent on flaw orientation. TOFD typically uses probes that are smaller and higher frequency than conventional and phased array pulse echo angle beam inspection probes. . length sizing is greatly improved by the benefit of having both technologies available during the inspection. 1R3 .com Free Download Manager.lnk V4.Questions or comments: PhasedArraySupport@Olympusndt.