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10:39 Mar-12-2010
IIW Block Type 2 for .25" wedge calibration

The Level III of my company pulled out his type 2 IIW block the other day. I noticed that it wasn't possible to calibrate a .25" angle beam wedge while still having the having the hash marks directly below the BIP of the probe. The recessed edge of the IIW type 2 was too far away laterally to be picked up by the probe. I was only able to pick up the 4" signal, not the 2".

So, my question is- Do they make IIW Type 2 blocks with hash marks on both sides for doing 2" & 4" linearity calibrations with a small wedge?

19:02 Mar-12-2010
Re: IIW Block Type 2 for .25" wedge calibration

David,

In all my time in NDT, I can't say I came across such a thing. The other thing that comes to mind is that it would be very difficult and may also give you some calibration error by moving your probe on each side of the IIW block to get the 2" than the 4". When you calibrate with such a block, you should position your transducer so that you will obtain a signal on your screen from the 2" and 4" simultaniously. In your case, this would require to place your transducer at the "0" mark and in the middle of the block thickness.

On easy way to solve your problem would be to use a fine tip waterproof marker and using a square, draw the line for the "0" mark across the width of the block. This way you would be able to maximize your signal and obtain a 2" and 4" signal on your screen.

Hoping this will e of help,
Cheerio's

00:32 Mar-13-2010
Re: IIW Block Type 2 for .25" wedge calibration

David,
The "industry-standard" IIW-Type 2 (Inch version) block contains the 60 to 80 degree scale on the face opposite the scale you are using to pick up the 4" and 2" signals. Placing a second radii centerline scale would shorten the 60-80 scale to 75 degrees (perhaps not a major roadblock), but would potentially lead to some confusion. We'd be happy to make you a special block that contains two identical radii scales. It may also be helpful to consider a narrower block width of 0.500" (12.7mm). Contact me if you are interested in pursuing this further.
Phil Herman
PH Tool Reference Standards

20:48 Mar-13-2010
Re: IIW Block Type 2 for .25" wedge calibration

Phil, I see that the mini-IIW block on the PH Tool website has a hash mark on the side of the recessed curvature. It appears to me that this would allow angle beam calibration with a .25" wedge. Is there any way you could test this out for me?

http://www.phtool.com/store/prodimages/miniiiw2lg-white-2ndhole.jpg