Welding Inspection

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I am part of the USF (university of south florida) SAE program we weld together 4140 tig welded chassis.I am curious about welding inspection before and after the races.I know of x-ray devices and seem to be pretty costly.I also was told about a power you can put on the metals to inspection.Anybody know of these methods?
Reply:Anybody familiar with Dye penetrant inspection or Magnetic-particle inspection
Reply:There are a variety of options, but the simplest  starting point, is in process visual inspection and qualifying welders/procedures through test samples.If there are no specified methods for the vehicle class, then there are a lot of options.Magnetic particle/magnetic flux methods: SHow discontinuities at the surface, and may show them below the surface (depending on the technique used), Cheap to very expensiveDye penetrant: Shows surface indications. The penetrant needs to penetrate into flaws. Usually cheapUltrasonic methods: Show under-surface features (cracks, inclusions, lack of fusion, etc), but requires training and skill. Equipment is moderately priced to very priceyRadiography (X-ray): specialist work. High skill level required to interpret. priceyProof load test: engineered test loads are applied to the structure that exceed the service load, but should be below the yield loads. Check for deformation or failure after proof loading. There are plenty of other options, but without more detail on what you are trying to look for, no specific answers can be given. We periodically get jobs with specs like "welds to be done by certified welder", but with no criteria (code, etc) specified. Do they mean AWS? ASME? Joes welding? Ditti for NDE: "Welds must undergo NDE" To what spec?  what are the acceptence criteria? NDE can be anything from visual to radiography with ultrasonic.
Reply:I would dye check the joints.  It will be quicker and easier than the mag test especially on tube clusters, and reduces the possibility of the iron powder making its way into your electronics.  The wall thicknesses are so thin on these cars that you will rarely have something sub-surface.
Reply:Originally Posted by enlpckThere are a variety of options, but the simplest  starting point, is in process visual inspection and qualifying welders/procedures through test samples.If there are no specified methods for the vehicle class, then there are a lot of options.Magnetic particle/magnetic flux methods: SHow discontinuities at the surface, and may show them below the surface (depending on the technique used), Cheap to very expensiveDye penetrant: Shows surface indications. The penetrant needs to penetrate into flaws. Usually cheapUltrasonic methods: Show under-surface features (cracks, inclusions, lack of fusion, etc), but requires training and skill. Equipment is moderately priced to very priceyRadiography (X-ray): specialist work. High skill level required to interpret. priceyProof load test: engineered test loads are applied to the structure that exceed the service load, but should be below the yield loads. Check for deformation or failure after proof loading. There are plenty of other options, but without more detail on what you are trying to look for, no specific answers can be given. We periodically get jobs with specs like "welds to be done by certified welder", but with no criteria (code, etc) specified. Do they mean AWS? ASME? Joes welding? Ditti for NDE: "Welds must undergo NDE" To what spec?  what are the acceptence criteria? NDE can be anything from visual to radiography with ultrasonic.
Reply:Originally Posted by SupeI would dye check the joints.  It will be quicker and easier than the mag test especially on tube clusters, and reduces the possibility of the iron powder making its way into your electronics.  The wall thicknesses are so thin on these cars that you will rarely have something sub-surface.
Reply:You can dye check both the 4140 and the Al.
Reply:Dye penetrant check is inexpensive and available from McMaster-Carr, MSC, Grainger, local welding shop, etc.There are three cans to the typical system: Cleaner (solvent), dye (penetrant), and developer (a powder in liquid carrier). Fluorescent dyes give increased sensetivity in some applications, but require a) a workplace that can be darkened, and b) the appropriate UV source to fluoresce the dye.From the university, you might want to contact manufacturers of the materials (Magnaflux Spotcheck is a common brand. Magnaflux is part of ITW, the parent company of Miller, Hobart, Smith, Tempil (temperature sticks), etc.) and talk to a rep. AWS meetings are a good place to meet these people, as well.The code requirements/test requirements should be part of your rules package. I don't know what, if any, testing is required by the SAE race programs. If there is no particular requirement, and you are concerned primarily with surface cracking, I would go with the dye check due to cost and ease of use.
Reply:Resurrection, tangential topic RFI:  Besides using a q-tip laced w/ sulfuric acid to check fusion extent to cross-sectioned slices of HRS, say, are there other "safer" chemicals to use for this purpose? Read about the H2SO4 technique on WTT, but would really like to use an alternative chemical/approach for determining depth of fusion into a section (post cutting and welding).  Will Corona work? Ha!"Discovery is to see what everybody else has seen, and to think what nobody else has thought" - Albert Szent-Gyorgyi
Reply:^ TestForEcho ^ Weak today my Google-Fu is.  Mahalo in advance."Discovery is to see what everybody else has seen, and to think what nobody else has thought" - Albert Szent-Gyorgyi