to ensure the soundness of the weld is use of DGS scales in Ultrasonic testing. order to bring the 3mm diameter disc on to curve II) then one uses the lines. Physics of NDT made clear by simulation · Ultrasonic Testing for Education · Eddy DGS (Distance Gain Size) or AVG (Abstand Verstaerkung Gröesse – in german) curves from manufacturer (Krautkrämer) are compared to simulation data for. block method the characteristic curve of the sound field is always determined before carrying out an ultrasonic test, whereas in the DGS method DGS diagrams.

Author: Fezuru Fehn
Country: Azerbaijan
Language: English (Spanish)
Genre: Life
Published (Last): 3 August 2014
Pages: 134
PDF File Size: 18.40 Mb
ePub File Size: 6.13 Mb
ISBN: 519-4-15816-890-3
Downloads: 45942
Price: Free* [*Free Regsitration Required]
Uploader: Tagul

It is important for you to protect against unauthorised access to your password and to your computer.

DGS/AVG | Olympus IMS

Ultrasonic Flaw Detection Tutorial. Be sure to sign off when you finish using a shared computer.

Since this reflector equals the selected registration level, the peak matches the curve at that depth. Any personal information provided to or to be gathered by bindt.

UT – FBH: DGS curves

Click here to unsubscribe Go. There is good agreement between simulation and measurement. The advent of digital instruments has made it possible to give the DGS system much greater flexibility, and most of the newer digital instruments will have a DGS capacity. Index of acronyms D DGS.


These are called the reference echo curves, and are used to set the correct sensitivity from the backwall. We work to protect the security of your information during transmission by using Secure Sockets Layer SSL software, which encrypts information you input. Based on its height and depth in relation to the curve the instrument calculated an ERS of 1. We reveal only the last five digits of your credit card numbers when confirming an order.

These types of scales are made specifically for a particular probe the B4S — 4 MHz, 24 mm diameter zero compression probe and shows a characteristic curve for 6 mm, 4 mm and 3 mm reflectors.

There are also two other curves — RE1 and RE2. The curves show a good agreement between simulated and experimental data for FBH deeper than the focal depth.

To learn more about how we use cookies on this website, and how you can restrict our use of cookies, please review our Cookie Policy. Frequency Crystal Mode Calibration flaw Calibration depth 1. It is always up to the user to determine how the resultant DGS calculations relate to actual flaws in real test pieces. In the early days of development of the DGS approach to DGS sizing, it was necessary to employ this generalised approach.

From that one calibration point, an entire curve set can be drawn based on probe and material characteristics.

DGS is a sizing technique that relates the amplitude of the echo from a reflector to that of a flat bottom hold at the same depth or distance. Part Three Training Courses: Alternatively, the curves can be used to find the size of the disc shaped reflector which would give the same size echo as a ultrasnic seen in the flaw detector screen. The input signal frequency is 1.


For more information on how to use a DGS diagram see: For each hole, the maximum amplitude of the specular echoes of the FBH is measured relatively to a calibration hole.

For small FBH above the focal spot the difference is up to 6 dB. It is much more useful, however, to use direct reading scales which can be fixed to the UFD screen for immediate size estimation.

It also shows a backwall echo BE to which the technician sets the backwall echo as the reference sensitivity. Please select the activities you want to receive information about: In the screen at right, a different reflector at a depth of approximately 26 mm has been gated.

DGS using digital display courtesy Panametrics click photo to enlarge. This notice describes the privacy policy of bindt. At longer beam paths, set the backwall to RE2 and add 8 dB.