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Up Topic American Welding Society Services / Technical Standards & Publications / AWS D1.1 Annex M, form M-8
- - By jwright650 (*****) Date 11-03-2009 17:23
Has anyone imported this form into Excel for easy calculations?

Just wondering....my calculation is coming up with a .1 error and I can't put my finger on where I went wrong.

ie. Row c calculation of the Corrected Reading
Parent - - By jwright650 (*****) Date 11-03-2009 19:17
LOL...I'm answering my own questions...LOL

I figured out that the example in the book has been rounded the wrong way(up vs down) and was throwing off the answer by 0.1.

My formula was working correctly all along...duh, silly me.
Parent - - By eekpod (****) Date 11-04-2009 11:08
are you talking to yourself again?  :)
Parent - - By eekpod (****) Date 11-04-2009 11:12
I tried to look at this to double check you, but it's been awhile since Ive done any UT, and then my eyes glazed over looking at all those charts and graphs, and then I said to myself, oh it's only .1 how much can it hurt so  I stopped.   :)
Parent - By jwright650 (*****) Date 11-04-2009 12:45
LOL....Chris, I haven't done any UT since the 1st of Aug. either. I was trying to get some of my manual forms over into Excel, so while I was calibrating/verifying the dB accuracy I was also trying to tackle the creation of this form.

Do any of you UT guys check your dB accuracy as often as D1.1 mandates? I have to be honest and say that I don't always remember to check this every two months, maybe every 4-5 months...time sneaks up on me and the two months will come and go before I think about this again. I'm trying to do better with this. I know that I shouldn't feel this way but this is one of those calibrations/verifications that never move on any of my UT machines and it sure seems like a waste of time. Wondering if this was something left over from the old tube type scope days?
Parent - - By jwright650 (*****) Date 11-05-2009 14:16
Hey Chris those little .1's add up (seriously), you have to add them up from  row "d" to find the collective dB Error(row "e").
Parent - - By eekpod (****) Date 11-05-2009 14:28
aahhh yeah, Row E, it gets me every time lol  :)

If this were an older analog scope would you even be able to pick up a .1 difference?
Parent - - By jwright650 (*****) Date 11-05-2009 14:39 Edited 11-05-2009 15:34
Hey check out my form....I'm still messaging it, but it's almost done.

edit: I updated the form with the correct spelling of supplemental
Attachment: UTCalibrationAnnexMexample.xls (39k)
Parent - - By eekpod (****) Date 11-05-2009 14:59
Wow you put a lot of work into that form and procedure, it looks great.

Your second bullet point about sliding the transducer and acquiring a new 40% screen height and adding 6 Db, basically your describing moving the transducer away from where it was and back to the same or similar area on the calibration block right?  not to a totally different spot? 
Not that it matters to me but I think that's what your describing, verses going from a 2"thick area to a 4"thick area.

Good work, can I steal in just in case I get a UT guy someday? :)
Parent - By jwright650 (*****) Date 11-05-2009 15:09
yessir if you can use it...go for it.

Using the DS block.....the beam starts spreading as you slide to either side of center, so your signal starts dropping on the screen as you slide towards the thicker part of the block, and when your signal drops back to 40% FSH, you stop moving and add 6 dBs and then record your new FSH% on the chart. I just put some random numbers in that chart so that it works....rows "a,b, and e" are manually input...the rest have the formulas built in. Your averages may change, so you may have to edit the formula so that you disregard the first and last 3 cells to get the average to work correctly. In the example they used all 13 spots, but on my machine, I get alot of tall grass towards the upper end and never can use all 13 spots.
Parent - - By jwright650 (*****) Date 11-05-2009 15:32
Oh Chris...I spotted another typo/mis-spelling....SUPPLEMENTAL INSTRUCTIONS....add the 2nd "E" in supplem(e)ntal
Parent - - By eekpod (****) Date 11-05-2009 20:24
you must be "mental" by now   ;-0
Parent - By jwright650 (*****) Date 11-09-2009 12:53
How did you know?
Up Topic American Welding Society Services / Technical Standards & Publications / AWS D1.1 Annex M, form M-8

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