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Recent content by doezer

  1. doezer

    securing a flared pipe end.

    Hi I think the crux of the problem is this reduction in weld strength for 6061-T6 when welded. so thats why the butt weld strength is in-sufficient, and im looking to go to a non-welded joint arranegement if possible. apologies if that wasnt clear in the posts..
  2. doezer

    securing a flared pipe end.

    hi. yes it is a continuation of the last one. sorry I should have added the link. I did provide some sketches the last time. The link to the sketch is in that last thread. Material is Al6061-T6. Im not sure why the statement "stresses are too high in the butt weld" is not clear? They are...
  3. doezer

    securing a flared pipe end.

    hi all... im looking for solutions would appreciate any help i could get here, i dont have much experience in pipe flange design to be honest. we're looking at the design of a pipe/flange connection here but unfortunately the butt weld stresses are just too high in the pipe wall to allow for a...
  4. doezer

    Pipe to Flange Design Question

    ok thanks for sure, increasing the 3mm constraint and staying with a butt weld is the easiest way to go. we need to push back on that a bit before embarking on this whole other road. D
  5. doezer

    Pipe to Flange Design Question

    youve written 'not possible' re pipe interference fit into a flange we do have some samples made up like that already, is it generally something considered not possible??
  6. doezer

    Pipe to Flange Design Question

    ok thanks. the excessive change in thickness wont be there.. it will neck down, sorry I should have drawn it that way. the pipe will be ~zero clearance. we think we have a way ;) its not cheap and a bit experimental, but we think can work. yet another possibility is hydroform the pipe into a...
  7. doezer

    Pipe to Flange Design Question

    ok here goes. i feel like im submitting an exam paper, go easy on me ;) dhttp://files.engineering.com/getfile.aspx?folder=84064d42-062c-460d-95e1-cf615169fa4d&file=butt_stress_vs_shear_stress.pdf
  8. doezer

    Pipe to Flange Design Question

    ok folks. some developments. If i compare the hoop stress (PD/2t) in the butt weld for a pressure of 200bar, OD 69mm, thickness 3.3mm I get a stress in the weld of 134MPa (= 19ksi) If I change that to an end weld, so just a face weld, welding the OD of the pipe to the flange face, I get a...
  9. doezer

    Pipe to Flange Design Question

    Thanks to all. im new to this forum and i have to say its really great to connect with other engineers with different beckgrounds like this...really helps so much ;) I hope to be able to contribute and not just learn on at least some of the forums at some stage down the line.. so the overall...
  10. doezer

    Pipe to Flange Design Question

    sorry. one more point. you say this is a very unusual requirement. the fact that we have high opertaional loads and high pressure loads. would it not be quite normal to have a pipe/flange joint which is subjected to high internal pressures, but also at the same time the entire joint is being...
  11. doezer

    Pipe to Flange Design Question

    Ok Thanks to LittleInch and all.. sorry. I do realise im drip feeding info here. i will attempt one last post with some info, and if its still not enough, i will have to go away and figure it out some more before i annoy you all any more ;) The material is Al6061-T6. i have inherited the...
  12. doezer

    Pipe to Flange Design Question

    thanks europipe.. i have an additional constraint. the material being welded is only good for welds to a depth of 3mm. the pipe wall thickness is larger than that (~4 or 5mm). so a full penetration butt weld is not a possibility here. So this is why i am thinking a support sleeve located...
  13. doezer

    Pipe to Flange Design Question

    @ BigInch Thanks a lot. But in my case I have to allow for quite a large loading occuring which is not due to pressure, it will be in the form of a bending load on the pipe, tearing it away from the flange so to speak. so wouldnt a supported 'sleeve' type weld be better here. intuitively this...
  14. doezer

    Pipe to Flange Design Question

    Secondly.... are there some online design guides available (youtube or otherwise) which can get a guy started on this... i.e. that cover pipe weld joint design... i can find a whole lot on basic weld joints (plates, fillets etc), but specific to pipes not so much Tnx
  15. doezer

    Pipe to Flange Design Question

    Hi all. i have very limited experiecne in weld design, and have been assigned a task to look at the design of a flange/pipe welded connection. im reading all over that a full penetration butt weld is the best. But why is that? When I look at a socket weld, the weld seems to be so much more...

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