OmniScan MX2 Training ProgramWedge Delay Calibration Wizard

2OmniScan MX2 Training Wedge Delay Wizard Overview The wedge delay calibration wizard is designed to measure and

offset the sound propagation between the probe and the exit point of the focal law in the wedge. (54.97usec below)

The function is exactly the same as conventional UT with the exception that all the variables are available to mathematically calculate it when exiting the setup group wizard and the function is performed on many A-scans or focal laws at the same time instead of just one.

3OmniScan MX2 Training Wedge Delay Wizard Overview cont. When the wedge delay is set correctly, 0mm on the A-scan corresponds to the exit

point of the wedge. The sound path propagation through the wedge is delayed out of the A-scan. Every focal law has a different wedge delay due to the different angles and exit

point on the wedge. Inaccurate wizard input for wedge and probe parameters or failure to calibrate the

wedge delay when needed results in inaccurate time of flight and depth readings. (SA and DA)

0mm

4OmniScan MX2 Training Wedge Delay Wizard Overview cont. Inputting the wedge, probe, and component parameters correctly into the

group set up wizard is the most accurate means of arriving at the correct wedge delay.

Use of the wedge delay wizard on a new or unworn wedge that was input correctly into the group set up wizard will not improve the reading accuracy and is a common source of problems and inaccurate inspection results.

Mechanical handling errors and errors due to side drilled holes being measured at different angles often reduce the accuracy of wedge delay compared to the calculator results.

The wedge delay wizard will not correct angle error or velocity error, only wedge height as pictured below.

Wedge velocity. Wedge angle. Height and position of

probe element #1.

5OmniScan MX2 Training Wedge Delay Verification After completion of the group set up wizard move the probe across the calibration

block visualizing a side drilled hole at a known depth. (20mm below) If the hole indication is consistent and at the same depth for all focal laws the

wedge delay is validated to the satisfaction of ASME, AWS, API and similar codes, a wedge delay wizard correction is not necessary, and ALL the below parameters will have been verified:

20mm SDH

Wedge velocity. Wedge angle. Probe element

height and position. Material velocity.

6OmniScan MX2 Training Wedge Delay Verification cont. If the SDH depth changes across the focal laws, it is an indication that one or more

of the parameters input into the group wizard were incorrect or out of tolerance resulting in refracted angle error.

An incorrect or out of tolerance material velocity error is the most likely parameter to cause this.

If the SDH is at a consistent depth that is a little short or long the wedge delay wizard can make the correction.

The wedge delay calibration wizard will not correct angle error or velocity error.

Correct wedge delay Angle or velocity error

7OmniScan MX2 Training Wedge Delay SDH vs Radius The MX2 has wedge delay wizard options for both sound path radius and

true depth side drilled hole (SDH) calibrations. The preferred and most accurate method is the sound path radius

calibration because it is not dependent on angle trigonometry and can be performed over a longer sound path typical of the IIW block below.

The true depth wedge delay calibration requires a trigonometry calculation that includes the angle. When the 70 degree is actually 69 it corrupts the wedge delay calculation when performed on SDHs in true depth mode.

The calibration block must be of the same material (Same velocity) as the inspection.

Sound path radius True depth SDH

8OmniScan MX2 Training Wedge Delay SHD vs Radius cont.

Sound path radius True depth SDH

Display>Selection>UT Mode = SP Display>Selection>UT Mode = TD

The wedge delay wizard will change the UT mode for the range and display based on the type of calibration reflector that is selected in the wizard.

If using a standard IIW block, select the UT mode for either true depth or sound path and adjust the range as follows prior to entering the wizard:

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100mm reflector

9OmniScan MX2 Training Wedge Delay Gage Mode Be aware of the selected gate measurement mode. (Peaks or edges)

Changing the gate measurement modes after calibration will affect the readings. The MX2 default is Peaks.

Enter the wedge delay calibration wizard by selecting Wizard>Calibration>Type Ultrasound>Mode Wedge Delay>All Angles.

Select start.

Peak Mode

Edge Mode

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OmniScan MX2 Training Wedge Delay Calibration Wizard Use Select Echo Type>Radius. Enter the radius sound path distance. (50 or 100mm if using standard IIW) Select Next.

Radius reflector

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OmniScan MX2 Training Wedge Delay Calibration Wizard Use

Select the last angle to be used in the calibration. (70 degrees) Some calibration blocks may have obstructions from a corner or adjacent reflector that requires performing the calibration in sections where the gate can be repositions.

When using a standard IIW block this is not necessary.

45-70 degrees 45-60 degrees 61-70 degrees

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OmniScan MX2 Training Wedge Delay Calibration Wizard Use Set the position of gate A to cover the radius (Pictured below) or true depth

calibration reflector. The vertical axis of the calibration window is represented by the gate start and width.

Set the threshold of gate A to 10% amplitude. Select Next.

100mm radius

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Focal laws and probe movement

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OmniScan MX2 Training Wedge Delay Calibration Wizard Use Select Clear Envelope and move the probe across the calibration block passing

each focal law through the 100mm radius maximum amplitude position. The white envelope trace represents the position in mm for the maximum amplitude

signal for each focal law. Prior to calibration the 57 degree focal law is reading 104mm in sound path. The

calibration wizard will correct each focal law to 100mm sound path by modifying the the beam delay that was originally calculated by the group set up wizard. (UT Settings>Beam>Beam Delay)

Select Calibrate.

57 degree focal law

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OmniScan MX2 Training Wedge Delay Calibration Wizard Use After selecting calibrate, move the probe over the block again passing each focal

law through the 100mm radius maximum amplitude position to verify that the wedge delay was modified correctly.

If the wedge delay calibration was successful the new white envelope trace will be contained within the tolerance window indicating all focal laws are detecting the 100mm radius +/- 1mm.

Calibrate can be selected repeatedly improving the calibration until the white envelope trace is contained within the +/- 1mm tolerance.

Select Accept and a green W is displayed in the MX2 indication area indicating that the wedge delay has been modified by the calibration wizard.

55 degree focal law

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OmniScan MX2 Training Wedge Delay Manual Edit

The calculated or calibrated beam delay for each focal law can be seen in UT Settings>Beam>Beam Delay.

In addition to the beam delays for each individual focal law there is a wedge delay parameter in UT Settings>General>Wedge Delay where all the focal law beam delays can be modified at one time.

Editing the parameter below allows a minor tweak to the beam delay of all focal laws and will remove the green W in the MX2 indication area that is present after wedge delay calibration wizard use.

This parameter is 0 under normal circumstances.

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OmniScan MX2 Training Wedge Delay Wizard Movie

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OmniScan MX2 Training Wedge Delay Wizard Movie

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