How to make controlled welding defects

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Hello everyone!I’m a student of university of technology and to my master thesis I must make some samples of weld with intend  (controlled) welding defects, which I can detect by NDT: VT, RT, UT, MT, PT.Type of steel (but it will be carbon steel) and weld (BW, FW) is irrelevant, I wonder how to do such a controlled defect. I came up with ideas:1. Lack of fusion and incomplete penetration - melt part of edge withTIG, rest part – MIG with solid wire2. Bonding (?) - after welding MIG with cored wire don’t remove the slag, then put another weld layer (stitch?), reduce the welding current for the moment)3. Gas inclusion - impose grease between layers4. Inclusions of tungsten - piece of the TIG electrodes put to the lake5. Cracks - little piece of copper put in welding lakeMaybe you have some other ideas, suggestions?If I used the wrong terms (words) then I'm sorryRegards
Reply:You can hire me to do the welds  "Any day above ground is a good day"http://www.farmersamm.com/
Reply:Originally Posted by gdmystnoHello everyone!I’m a student of university of technology and to my master thesis I must make some samples of weld with intend  (controlled) welding defects, which I can detect by NDT: VT, RT, UT, MT, PT.Type of steel (but it will be carbon steel) and weld (BW, FW) is irrelevant, I wonder how to do such a controlled defect. I came up with ideas:1. Lack of fusion and incomplete penetration - melt part of edge withTIG, rest part – MIG with solid wire2. Bonding (?) - after welding MIG with cored wire don’t remove the slag, then put another weld layer (stitch?), reduce the welding current for the moment)3. Gas inclusion - impose grease between layers4. Inclusions of tungsten - piece of the TIG electrodes put to the lake5. Cracks - little piece of copper put in welding lakeMaybe you have some other ideas, suggestions?If I used the wrong terms (words) then I'm sorryRegards
Reply:I use manufactured flawed specimans for the NDT training that I do, there are several companies that manufacture flawed specimans, but the only ones I have used are FLAWTECH.  You can buy individual pieces or sets and each piece comes with a print mapping out the location of the flaw, description of the flaw and difficulty level of dectecting the flaw.  They are expensive, but will last several lifetimes and I believe are absolutely a must have for an effective NDT training program.  www.flawtech.com6 Miller Big Blue 600 Air Paks2 Miller 400D6 Lincoln LN-25's4 Miller Xtreme 12VS2 Miller Dimension 812 4 Climax BW-3000Z bore welders Hypertherm 65 and 85Bug-O Track BugPair of Welpers
Reply:I'm with ExpatWelder on this.  Trying to make flawed specimens is not easy - usually the implanted 'flaw' get's out of hand - too big for reality testing.  I worked with two companies that tried this... a real challenge. From 1998 until 2009, I managed the Federal Government NDT Certifying Agency for Canada.  Most all our specimens used for NDT examinations came from manufacturers who detected flawed production pieces.  We documented these and introduced them into our specimen inventory.  In the last few years we did try to make a few of our own welded speciemns with flaws for a new visual program... but we mostly ordered 'exactly' what we wanted from the experts: a) Flawtech and b) SONASPECTION.Rick V 1 Airco Heliwelder 3A/DDR3 CTC 70/90 amp Stick/Tig Inverters in Parallel1 Lincoln MIG PAK 151 Oxy-Acet
Reply:Manufacturing of welded joints with realistic defectsMarcello Consonni Author, Chen Fun Wee Coauthor and Charles Schneider CoauthorTWI LtdPaper presented at NDT 2011 - 50th annual conference of the British Institute of Non-Destructive Testing, 13-15 Sept. 2011. Telford, UKAbstractIntentional weld defect or flaw specimens can be required for training purposes, developing new non- destructive testing techniques, qualifying non-destructive testing procedures, obtaining mechanical property data and in support of safety cases. The single most important criterion in producing defects or imperfections is that they must accurately simulate flaws which can occur in welded components and structures. For this reason, in certain applications, saw cuts or machined slots which are more easily detected may not be considered acceptable as planar imperfections/defects for the purpose of NDT training or validation. Therefore, TWI has developed techniques for producing realistic imperfections/defects and, in the case of cracks, the desired morphology, including roughness, angles of tilt and skew to the surface.This paper describes the techniques used to obtain the abovementioned defects and, for the most commonly required defect types, the qualification procedure used by TWI. This consists of inspecting by testing by surface crack detection, ultrasonic or radiographic inspection and/or sectioning to demonstrate that the dimensional tolerance of the simulated imperfections (ie actual size of the imperfection vs required size) can be generally guaranteed within ±0.5mm in through-wall extent and ±1mm in length.1. BackgroundIntentional weld defect or flaw specimens can be required for non-destructive testing (NDT) operator training and validation, to develop validated NDT procedures or new NDT techniques, to obtain mechanical property data and in support of safety cases. The single most important criterion in producing defects or imperfections is that they must accurately simulate flaws which can occur in welded components and structures. In particular, when summarising the work carried out within the PISC project series (Project for the Inspection of Steel Components), Crutzen et al[1] concluded that the NDT procedure has to be validated and tested on structures containing defects that, not being necessarily real ones, still do induce the real physical phenomena that the inspection techniques must be able to handle. Crutzen et al also stated that the use of very artificial discontinuities (side-drilled holes, SDH or flat-bottomed-holes, FBH) to demonstrate the capabilities of NDT techniques often results in optimistic statements and hazardous use of the technique on structures containing real defects. When comparing the use of welded joints with real or artificial realistic flaws (see definitions in Section 2), Crutzen listed the following advantages for the latter:•Less expensive and time-consuming fabrication •The possibility of more certain characterisation •The provision of non-contaminated assemblies that can be more easily used for effectiveness assessments •The consideration of more relevant selections of structural geometry and materialIn this same review, facts appearing in favour of the use of artificial crack-like defects for NDT performance assessment were reported.3. Deposition of realistic defects at TWI3.1 GeneralThe vast majority of realistic defects produced by TWI are obtained by weld modification, machining or by growing defects (methods 2 to 4 as defined in Section 2). A full list of defects that can be deliberately inserted into welded joints is given below:•Lack of side-wall fusion •Lack of root fusion •Slag inclusion •Solidification cracking •Cluster cracks •Weld metal transverse cracking •Porosity •Heat affected Zone (HAZ) cracking •Brittle fracture and fatigue cracksThis section shows a few recent examples of the techniques used to obtain the above defects and their application, for the different defect types. Details of the techniques not described in this paper are provided in a previous publication by TWI, which summarises the work carried out in support of the safety case for the Sizewell 'B' PWR power station in the UK (Lucas[5]).3.2 Lack of side-wall fusion (LOSWF)Lack of side wall fusion defects are obtained with two techniques:•TIG bridging •Use of a metallic or non metallic insertThe 'TIG bridging' technique consists of outlining the edges of the defect on the weld edge with TIG runs, then bridging the area between them with further TIG runs, deposited so that no fusion with the base metal is obtained. The morphology of defects obtained with this technique is shown in Figure 1.
Reply:I can't make defective welds anymore..I have tried and failed. ...zap!I am not completely insane..Some parts are missing Professional Driver on a closed course....Do not attempt.Just because I'm a  dumbass don't mean that you can be too.So DON'T try any of this **** l do at home.
Reply:Originally Posted by zapsterI can't make defective welds anymore..I have tried and failed. ...zap!
Reply:Just hire are buddy Sean:Sorry folks, has to do it. kidtigger24  They think I’m crazy, but I know better. It is not I who am crazy. It is I who am MAD!
Reply:Scary Stuff! Rick V 1 Airco Heliwelder 3A/DDR3 CTC 70/90 amp Stick/Tig Inverters in Parallel1 Lincoln MIG PAK 151 Oxy-Acet
Reply:Alright who in the name of sweet FVCK is that guy?!They'll let anyone on youtube for chrissakes!Buy American, or don't whine when you end up on the bread line.
Reply:hahaha i like to leave a little "nublet" sticking out too! 1.35s-NateMiller Trailblazer 302gMiller Spoolmatic 30aLN-25 x 2Idealarc SP200Hypertherm Powermax 600
Reply:YOWZA, holy crap!
Reply:Originally Posted by CilvestDradI use manufactured flawed specimans for the NDT training that I do
Reply:I'm not sure how to add You-tube videos, but maybe someone can put up some of Dannyscam videos. You remember the backwoods barefoot "welder". He can do the perfect defective welds without even trying, he is just that good.
Reply:Originally Posted by BistineauI'm not sure how to add You-tube videos, but maybe someone can put up some of Dannyscam videos. You remember the backwoods barefoot "welder". He can do the perfect defective welds without even trying, he is just that good.
Reply:Originally Posted by BistineauI'm not sure how to add You-tube videos, but maybe someone can put up some of Dannyscam videos. You remember the backwoods barefoot "welder". He can do the perfect defective welds without even trying, he is just that good.
Reply:Originally Posted by zapsterUmmmmmmmmmmLet's try to keep that fine gentleman out of this thread..OR ELSE..We don't need that crap here once again..Thank You....zap!
Reply:Not me....zap!I am not completely insane..Some parts are missing Professional Driver on a closed course....Do not attempt.Just because I'm a  dumbass don't mean that you can be too.So DON'T try any of this **** l do at home.
Reply:Originally Posted by zapsterNot me....zap!
Reply:Originally Posted by zapsterUmmmmmmmmmmLet's try to keep that fine gentleman out of this thread..OR ELSE..We don't need that crap here once again..Thank You....zap!
Reply:These guys may be able to give you some pointers...http://www.sonaspection.com/index.html
Reply:When I did this is school I used a 7018 on the second layer and others about 1/2 to 1 inch long. Slag was left on the beads and weld was finished with GMAW SAW and FCAW, flux showed up in RT and UT.Lack of fusion was attempted with degrees of success by welding over carbon dust(insulation blanket) also had good luck pushing mig at an angle that was very close to causing porosity and traveling to fast. Alternate method is to run a GMAW bead at lowest amperage possible on a 2 inch thick or thicker plate with heavy mill scale, bead is easily removed and placed inside a weld coupon then welded over.You can also get a nice defect by running a root pass with 7018 and use a pushing technique. flux should insulate the metal a create a lack of fusion defect. A similar defect can be done with GTAW on alluminum by melting the filler metal in the arc on the root pass and not melting the base metal, hard to do on fill and cap but possible if plate is over 3/8 inch and allowed to cool before placing the defective pass.john