Testing shear connectors/studs

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quick question if anyone can point me to a spec about testing nelson studs under structural codes. Wondering if a 10 pound beater is out of line for the inspector to use.  ThanksWeldanpower 225 G7Ironworkers Local #24
Reply:I don''t think there is actualy any code saying what size beater they can use......lolThey use a beater to bounce off the studs to listen to it,,if it has a certain "ring" to it,it wasn't welded 100%...And they will beat one over in a certain percentage of of the area until it practictly folds completely over and if it breaks..FAIL..They generaly use a 6-8# beater but it really just matters what they have on handLincoln Ranger 8 225Lincoln 180 ProMigMiller Maxstar 200DXInternational Ironworkers Local 70930+ years and counting
Reply:You hit them or use a pipe over the stud to bend them at 30 degrees from perpendicular.  Usually your Code will tell you how many have to be bent to proof.  It is something like 2 % if you are putting in hundreds.   You need a pretty big hammer if they are 3/4 inch diameter and a 2 pounder will do fine if they are 1/2 inch.  Also you are supposed to proof bend something like two before you start... anytime you change diameter or length of stud you have to do a test again on scrap.You are going to have to get a copy of the relavent pages from the Canadian or American code.  If you have a friendly inspection company they will provide you with the information.  It is in their interest so that they are not making second trips inspecting repairs.  Jbrd should be able to answer this one and if he can't we will write a letter to revoke his CWI  Ha HaLast edited by lotechman; 12-02-2011 at 09:27 PM.
Reply:[QUOTE=FabCrazyGuy;580726]I don''t think there is actualy any code saying what size beater they can use......lolthe point is that I could break off studs he couldnt, if I used my long handled 16 pounder. The meaning of a specification is to spell out the exact conditions. "Condition, Task, Standard" in army speak. pic of a defective stud. The nugget missing from the body of the stud should not be missing. Likewise, the other studs we look at yesterday have base metal, from the beam, attached to them. The weld didnt break, the flange did. Revisit the size of beater used. use one big enough and you will start to deform the beam if it is attached with a good weld.Not an ironworker's problem if the engineer spec'ed out small beams. My two pound deck hammer produced a satisfying tone when striking the studs. I could also feel the beam under my foot vibrate. Usually means the weld is good. And to avoid the frustrations of a ******** inspector, I dont pull any punches when I QA the studs. We reshot more on our own accord than the inspector broke off. Ive never seen an inspector so far, besides this guy, use anything other than a 16 or 32 oz ball peen. Attached ImagesLast edited by tenpins; 12-03-2011 at 02:03 PM.Weldanpower 225 G7Ironworkers Local #24
Reply:Originally Posted by tenpinsWondering if a 10 pound beater is out of line for the inspector...
Reply:Most of the Inspectors i've seen use a long handled 6-8 pound beater,they will walk all around the studded area just sort of bouncing the beater off a stud and listening to the ring tone,and beat one over every once in a while to see if the weld breaks.I've seen some only bend them over to a slight 30 degree,and some practictly bend it over touching the decking or beam..i geuss its all up to the personal choice of the QC Inspector as to how far.Looks to me like that stud broke off in the HAZ area,which is pretty normal,but then again now a days you really never the quality of the studs aymore because so many of them are shipped from over seas,i hung iron on a job up in Morgantown WV a few years ago on a new coal burner and alot of UT's were failing left and right..long story short,it was a Foster/Wheeler designed and built and the steel was from China and it was junk,alot of it was shipped out and replaced with local made and fabbed iron...so much goes for the so called money they was supposed to be saving on that cheaper China steel...Lincoln Ranger 8 225Lincoln 180 ProMigMiller Maxstar 200DXInternational Ironworkers Local 70930+ years and counting
Reply:Originally Posted by DSWNo, Feel free to beat him with what ever you'd like to...
Reply:Originally Posted by DSW No, Feel free to beat him with what ever you'd like to...
Reply:Originally Posted by FabCrazyGuyYou just do not KNOW how many of them i've wanted to do that....lol
Reply:Originally Posted by FabCrazyGuyYou just do not KNOW how many of them i've wanted to do that....lol
Reply:Originally Posted by lotechman  Jbrd should be able to answer this one and if he can't we will write a letter to revoke his CWI  Ha Ha
Reply:jbyrd if you could forward anything about testing shear connectors, that would be really appreciated.Weldanpower 225 G7Ironworkers Local #24
Reply:From the Canadian code it is a bit different than you describe the inspector doing.  In fact it sounds like he really doesn't know the code.   First thing the operator to start production for the shift must shoot two studs on scrap that is comparable thickness ( plus or minus 25 %)  to the work.  Those two studs are inspected visually to ensure there is full 360 degree flash around the connection.  After  cooling the studs must be bent 30 degrees without failure.  Below 10 Celcius the bend must be done by "continuous slow operation."  ( meaning a pipe not hammer)  If they are threaded studs a torque test must be done.  Two consecutive studs must pass.  Now you are ready to start the shift. The operator starts production and the first two studs done on the work are similarly tested.   If a new operator takes over the production he must bend test his first two studs shot on the work.   One stud in every 150 shot will be tested by bending to 15 degrees as production continues.   Any stud that fails to have flashing 360 degrees shall be bent at 15 degrees and left.Any stud that requires welding repair shall also be bent 15 degrees and left.  Bent studs shall be left unless they will be one inch away from the concrete surface when the concrete is poured.   This is from a 1989 Canadian code.  The AWS code will be similar with slight variations.If the inspector is on the ball the first thing he should be asking is to see the practice pieces that the operator used to start the shift.  I got reamed out by one engineer.  It was gentle reaming out but enough to make me cover my butt from then on.  I had checked my settings and then cleaned up around the work area throwing my scrap and every other stud on scrap in the bin.  The inspector just has to walk down with a flashlight checking that there is 360 degree flashing on each stud or or that it has been weld repaired and bent 15 degrees.  He should see one stud in 150 bent to 30 degrees.
Reply:Originally Posted by tenpinsjbyrd if you could forward anything about testing shear connectors, that would be really appreciated.
Reply:Something that will give you inconsistant results when shooting studs is if you leave your leads coiled up.  It is important to run the leads out on the floor.  If they are coiled they will create a back current effect.  The short pulse of very high current (sometimes over 1000A) will cause a magnetic field to be built up in the coils and then collapse when it shuts off.  This pulse will cause problems with your stud shot.  The better suppliers of the studs and rental machines will give you a handout giving recomended settings and a troubleshooting diagram explaining what to do if you get too much flashing, too little flashing or other physical appearances.  The one I got from a supplier was photcopied from a competitor.  He apologized for his company not having the literature and asked me to no show it around if other stud suppliers were nearby since it was sort of a copyright infingement.  Maybe by now someone has published a guide sheet online.  Yes they have!...  I lived much of my career pre-internet.http://www.imageindustries.com/pdf/a...ders_guide.pdfhttp://www.internationalwelding.com/pdf/trouble.pdf  If you look at a stud before it is shot you will notice a piece of aluminum imbedded in the tip.  From what I can understand the aluminum is the ignition point and it acts as a deoxidizer grabbing any oxygen from the weld pool and forming aluminum oxide slag.
Reply:AWS D1.1:2010 Clause 7 lists a visual inspecion requirement and a possible bend test on production welds, depending on the visual.  If you have less than 360 degrees of flash, or the stud has been repaired by welding, the stud shall be bent 15 degrees with either a hammer or a piece of pipe.  No specificaitons on the hammer weight.  Studs shall be bent in the direstion opposite from the missing flash.  Threaded studs will be torque tested (not to destruction, to a ft/lbs. value)As mentioned above, there are a several pre-production tests that must be done as wellThis is just what the code says, contract may have additional requirements
Reply:Originally Posted by tenpinsjbyrd if you could forward anything about testing shear connectors, that would be really appreciated.
Reply:Lotechman and Fred, thanks for those replies. Ive saved the guides to look over and reference in the future. Fred, that's why Im always looking for the spec! In my experience, the "test" was to bend it to a 45, but in the thread above others state 30...and the spec says 15. Very cool, thanks for looking all that up.Weldanpower 225 G7Ironworkers Local #24
Reply:Originally Posted by tenpinsIn my experience, the "test" was to bend it to a 45, but in the thread above others state 30...and the spec says 15. Very cool, thanks for looking all that up.
Reply:AND that is why in the mid '80s I took a welding inspection course.  From then on I could politely lead inspectors in the correct direction since I knew as much as they did.  It is frustrating to have an inspector lord over you and you really not sure if he is standing on the standards or some whimsical determination.   Last year I saw an inspector go back to his car and carefully unwrap a digital level.  He placed it on a weldment that was over 15 feet wide with welds every 18 inches across.  Here is the punch line:  It was a little six inch torpedo level!!!  If I was the foreman I would have politely commented on his nice level, taken a picture of it on the weldment and emailed the picture back to his supervisors suggesting they send someone else next time.
Reply:Originally Posted by lotechmanAND that is why in the mid '80s I took a welding inspection course.  From then on I could politely lead inspectors in the correct direction since I knew as much as they did.  It is frustrating to have an inspector lord over you and you really not sure if he is standing on the standards or some whimsical determination.   Last year I saw an inspector go back to his car and carefully unwrap a digital level.  He placed it on a weldment that was over 15 feet wide with welds every 18 inches across.  Here is the punch line:  It was a little six inch torpedo level!!!  If I was the foreman I would have politely commented on his nice level, taken a picture of it on the weldment and emailed the picture back to his supervisors suggesting they send someone else next time.
Reply:Hope I didn't ruffle any feathers when I said testing the studs with a hammer and listening for the ring isn't acceptable test method.  I meant that only from the standpoint that it isn't covered in D1.1.  As far as a general practice I know that by the sound alone you can determine whether it had a 360 flash fusion.  I know my mentor used that very same method on EVERY stud in L.A. County.  I also know from personal experience how ego plays a part in some CWI's decisions.  I too have been picked apart by CWI's, and in hindsight they were feeding only their own self worth.  In my experience a lot CWI's have a pet peeve or one little thing they like to see or harp on.  My goal is that as my career advances into the inspection field that I keep things rooted in fact and what criteria is acceptable by code, contract docs, or the eingineer.  That way I get to sleep at night.Regards,Jay DavisAWS-CWIC-60 Specialty Welding ContractorLoving husband, and father of two boys (
Reply:This problematic inspector in my original post works for a company that also has one fo the ebst inspectors on this planet. Reasonable, fact based and by the book. Over the years he has inspected on my jobs, if he rejects something, he whips out his book or sometimes even a photocopy of something, and shows it to us. That way I know _exactly_ what the standard is, and I can fix it pronto. Likewise, when a weld is called for that is impossible to reach, he will work with us and the engineer to come up with an acceptable fix. Because of this business first approach, everyone likes him. I wish many many more were just like that.Weldanpower 225 G7Ironworkers Local #24
Reply:Tenpins has it right.  In my experience if you work with your inspector things go smoothly.  Everyone knows what has to be done and how things have to repaired.  Once you develop a relationship often they will even sign off on something that needs a minor repair knowing that they can trust you to fix it and save themselves a return visit.
Reply:30 deg deflection.    I use a 16lb long handle apprentice tamer.      never had much beef from an inspector over my stud welding.Vantage 500's LN-25's, VI-400's, cobramatics, Miller migs, synch 350 LX, Powcon inverters, XMT's, 250 Ton Acurrpress 12' brake, 1/4" 10' Atlantic shear,Koikie plasma table W/ esab plasmas. marvel & hyd-mech saws, pirrana & metal muncher punches.Originally Posted by Dualie30 deg deflection.    I use a 16lb long handle apprentice tamer.      never had much beef from an inspector over my stud welding.