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Up Topic American Welding Society Services / Certifications / Preparing coupons?
- - By Tate48 (*) Date 05-08-2015 20:36
Hello all,

I have posted once before and found this is the place for great help. I teach at two schools and found that people have two ways of doing things. I was taught that when prepearing side bend coupons to be bent to D 1.1 you remove the backing strip, grind down the face reinforcement and the root down to flush with the plates. Then you radius all the sides no more than 1/8. While observing at the other site I notice they cut the coupons and remove the backing then bend them as as. We looked in the code book D1.1 and both made good arguments for both. So, my question is what way is right or are both ways acceptable?

Thanks
Parent - By SCOTTN (***) Date 05-08-2015 22:07
I wonder how many failures they've had because they are not adding the radius to the coupon corners.  The radius is there to help prevent tearing at the otherwise sharp edges of the coupons.  I've never attempted to bend one without radiused corners.
Parent - - By jrw159 (*****) Date 05-08-2015 22:48
Tate48,
  I would be interested in hearing the arguments that it is not required by code.

jrw159
Parent - - By Tate48 (*) Date 05-08-2015 23:19
We looked at figure 4.13- Side Bend Specimens. I told the other instructor that the code shows the specimens with radius edges. He said that the book gives a max and  no min on radius so we do not have to. Then when it comes to the face and root I said the image show no face reinforcement and a flush root. He said that no where does it say the reinforcement have to be removed flush. So, I looked and could not find anything that said it. I know that Figure 4.12-Face and Root Bend Specimens gives note c which tells to remove it. At that point I had no where else to go. So, I came here for help. Any pointers would help.

Thanks
Parent - - By jrw159 (*****) Date 05-09-2015 01:33 Edited 05-09-2015 02:01
OK, let’s do the easy one first. In Figure 4.12, Note C clearly indicates that the weld reinforcement and backing SHALL be removed flush with the surface of the specimen. Locations for Note C are indicated for face and root bends by arrows. Now we go to Note 2 for plate thickness less than 3/8" the nominal thickness shall be used for face and root bends. You can not have nominal thickness if you have not removed the weld reinforcement.

Moving to Figure 4.13 you can clearly see that the weld reinforcement is to be removed. As for the backing being removed, you are correct in the fact that it does not say to remove the backing. This is because it does not need to be said. If this is for WPS qualifications see 4.9.1.1 (5). How can you perform the required visual inspection of the root without removing the backing?

You may say “We are not doing WPS qualifications, we are doing welder qualification.”

OK, see table 4.11 note A (this applies to both side bends and face and root bends). All welds shall be visually inspected (see 4.31.1). 4.31.1 Visual Inspection See 4.9.1 for acceptance criteria. We are right back where we were. How can you visually inspect the root if you do not remove the backing?

Now let’s look at the radius question.

If you look at Figure 4.12 the face and root bends show a radius of 1/8" max. Now look at the longitudinal bend specimen. Notice it does not show any radius info at all. This is due to the fact that the weld area is contained in the parent material as opposed to face and root bend specimens where the weld area is exposed on the sides.

I would apply that logic to Figure 4.13 as well.

My view is that even though it does not show a minimum radius dimension, it still shows the radius thus is required by code. The max 1/8" radius is in place so that one does not turn the specimen into round bar. LOL

Al touched on the fact that "the code is simply assessing whether the welder has the minimum skills needed to pass the soundness test." you have less of a chance of a corner crack with the radius.

Now having said that, if they do not want to radius the edges for whatever reason (takes to much time/want to make the test harder to pass/or just plain bullheaded) I would say more power to them in this situation because it does not sound like they are qualifying welders for a code job.

jrw159
Parent - By Tate48 (*) Date 05-09-2015 02:34
Thanks jrw159,

You made the same arguments that I made. His stance is that we are doing side bends so he only looks at Figure 4.13 Side Bends Specimens and there is no note for that says the weld reinforcement shall be removed and Note c only applies for Figure 4.12 Face and Root bend Specimens.

I only want to do what is right.

Thanks again
Parent - - By Tate48 (*) Date 05-09-2015 02:37
Thanks jrw159,

You made the same arguments that I made. His stance is that we are doing side bends so he only looks at Figure 4.13 Side Bends Specimens and there is no note for that says the weld reinforcement shall be removed and Note c only applies for Figure 4.12 Face and Root bend Specimens.

I only want to do what is right.

Thanks
Parent - - By jrw159 (*****) Date 05-09-2015 04:11
Tate48,
  It clearly shows the removal of the weld reinforcement in Figure 4.13 with the dotted lines. look at the specimen that shows the radius info. There is no weld reinforcement depicted. for the 3/8" specimen, no weld reinforcement depicted. for 1 1/2" and up, weld reinforcement is shown in dotted lines to be removed.

Even the 6GR figure shows the removal of the weld reinforcement.

Also as Brent points out " Information in Figures and Tables need not have supporting text."

I know what you are going through though. Some people will play twister with words and figures to try to make it suit their needs/wants. It is really pretty cut and dry though. IMHO

I think you are doing the right thing and your right.

jrw159
Parent - - By Tate48 (*) Date 05-13-2015 19:04
Alright we had another discussion and they still have questions. I used all of your examples jrw159 and they were very helpful. Some still feel that we do not need to remove the face reinforcement but have to agreed too for the sake of uniformity in the school.

This brought up a new question. You mentioned that the 6GR figure shows the removal of the weld reinforcement, so I pointed this out. Then someone pointed to the arrows on the 6GR Specimen that point at the dotted lines. Under the arrow it states Machine the minimum amount needed to obtain plane parallel faces (Optional).  Why the optional? This brought up more confusion.

Thanks All!
Parent - - By jrw159 (*****) Date 05-14-2015 01:15
Tate,
  It is indeed "optional" for the 6GR coupons. As to why, I have no idea. Maybe some of the more Seasoned Veterans can answer this for both of us.

I will do some more digging on my end to see what I can come up with.

Also I want to give a big shout out and THANK YOU to the Welding Engineer where I am employed. His door is always open and he is always willing to spent a little time to help a person. He has helped me to insure that answers I give are correct to the best of my knowledge.

Thank you Mr. JAMES VELA!!!!!!

jrw159
Parent - By welderbrent (*****) Date 05-14-2015 03:50 Edited 05-14-2015 04:07
Hello John,

Guys, it isn't that difficult.  Look at Figure 4.13 and read the application: "Side Bend Specimens".  So, looking at the figure, you have a 'side' view.  Now, make it practical.  You are going to bend test this coupon.  With a SIDE bend.  Which sides are critical?  The ones you are viewing.  Thus, it is optional because you can leave that material and still perform a side bend.  For a side bend you need it cut at 5/16" which is the other direction.  We are looking at one 'side' of the coupon.  Either the side in the view or the opposite side will be the stretched side going into the guided jig.  But the top and bottom are not relevant.  So, optional. 

As Al stated, though slightly different context, you can see more about the integrity by leaving the reinforcement there on both the face and the root.  If all is good it will bend just fine.  If not, BREAK/BUSTED!  Now, it is optional because they are leaving it to the test provider.  Some equipment may not handle the specimen well if not squared off either because of size restrictions or ability to handle the stress of the extra material.  And, we are not talking about a face and root bend, this is a side bend of the 6GR coupon.  If it were a face and/or root I would still stand on the wording stated previously, "shall be removed flush with the surface of the specimen."  (seen in Figure 4.12 for face and root bend specimens) 

Keep the differences in mind between face/root and side bends as well as plate vs 6GR Pipe.  Different materials and test preparation.

He Is In Control, Have a Great Day,  Brent
Parent - By welderbrent (*****) Date 05-09-2015 01:49
I would argue that a little differently.  The point is that it calls for a radius and then gives a maximum at which it is to be done.  It does not say, 'if you radius'.

" He said that no where does it say the reinforcement have to be removed flush."   Someone better take a closer look at Figure 4.12 and 'note c' is referenced more than once.  Go to note 'c': "The weld reinforcement and backing, if any, shall be removed flush with the surface of the specimen (see Clause 5.24.3.1 and 5.24.3.2)."  Clause 5.24.3 has to do with Flush Weld requirements. 

1) Even if you only give the edges a lick and a promise, with a sander of course, then my view is that the code does indicate that as a minimum and a 1/8" radius as a maximum.
2) The code most assuredly does say that weld reinforcement is to be removed flush.  That is the guide given as the text sends you there in order to see how coupons are to be prepared.  It does not have to be stated in the text as per previous statements by the committee that information in Figures and Tables need not have supporting text (see 'Official Interpretations' for confirmation).

Just my two tin pennies worth.

He Is In Control, Have a Great Day,  Brent
- By 803056 (*****) Date 05-08-2015 22:10
For training, I bend the sides bends with the face reinforcement and the backing intact, with no radii on the corners. If the sample is sound; it bends without a problem. If there is a defect in the root; it will tear.

For the performance qualification; I follow the code. After all, the code is simply assessing whether the welder has the minimum skills needed to pass the soundness test.

Best regards  - Al
Up Topic American Welding Society Services / Certifications / Preparing coupons?

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