02:29 Aug-09-1999 Rolf Diederichs Director, Editor, Publisher, Internet, PHP MySQL NDT.net, Germany, Joined Nov 1998 602
Re: TCG Defination of "TCG"
Time-dependent gain (TDG)
Time dependent or swept gain function fitted to some ultrasonic instruments to correct for the distance related reduction in reflected amplitude. Editor comment: Usually called DAC 'distance amplitude correction' or TCG 'time controlled gain'
This definitions is used in the standard EN 12688-1 "Characterization and verification of ultrasonic examination - Part 1: Instruments" For other definations the EN 1330 shall apply. http://www.ndt.net/article/ut_az/ut_u/info/def_eq.htm
---------------- : Dear Sir, : I am very interesting to see your nice homepage. : Please help me Sir, I want to know information about the Time Corrected Gain Ultrasonic (TCG-theoritical)).
Re: TCG : Dear Sir, Thanks for response soon, I have an USD 10 (krautkramer), and for reject of assumption I used TCG. My question is how to applied and procedure of TCG ? I can operate TCG corresponding to manual USD 10 but I don't know to apply for reject. is the TCG include ASME, DGS, or AWS standard ? I want to change information, may be everbody do you have experience to use USD 10 ?
03:48 Aug-10-1999 E. Ginzel R & D, - Materials Research Institute, Canada, Joined Nov 1998 1208
Re: TCG Mudi: ASME Section V Article 4 Appendix B Gives instructions on how to construct a Distance Amplitude Correction curve to set your primary sensitivity. These instructions are for the "traditional" curve drawing marked directly on the screen. However, the CURVE is one option for the amplitude correction that is required with increasing soundpath. When you go to the main body of ASME Section V Article 5 T-542.4.3 (as well as Article 4 Appendix B) it states that other techniques for calibrating angle beams may be used. Since TCG (Time Corrected Gain) is merely a convenient method of increasing gain as distance along the timebase increases, this effectively allows you to provide the same sort of compensation to sensitivity as is provided with the DAC curve. The advantage of the TCG is that for greater distances the signals to evaluate are a smaller percentage of the total screen height when using a DAC curve. But when TCG is used the signals evaluated for 20% of the Reference sensitivity are the same screen height at 90% of the screen range (soundpath) as they are at 20% of the screen range.
I do not know the requirements for AWS but the wording in ASME obviously permits TCG.
: : Dear Sir, : Thanks for response soon, : I have an USD 10 (krautkramer), and for reject of assumption I used TCG. My question is how to applied and procedure of TCG ? : I can operate TCG corresponding to manual USD 10 but I don't know to apply for reject. : is the TCG include ASME, DGS, or AWS standard ? : I want to change information, may be everbody do you have experience to use USD 10 ?