JOINT TYPE FOR WPS

  1. paul teggart Member

    Messages:
    19
    Location:
    Dungannon, county Tyrone, Northern Ireland
    Hi Guys, could someone please help clear something up.
    If you have a 10mm thick circular plate of say 300mm diameter, with a 5mm 45° chamfer on the side, to be welded inside a pipe of the same diameter and thickness, (plate sitting in a couple of inches and totally accessible as pipe will be vertical and plate horizontal), what type of joint is that? And what would the ranges be for someone tested to it as per ISO 9606-1.

    Thanks very much guys for the feedback.
     
  2. Richard.

    Richard. Forum Supporter

    Messages:
    18,350
    Location:
    Cambridgeshire
    Put up a sketch of the joint but from your description it sounds like a double V butt joint.
    As far as welding codes go a multi run 4G coding would cover a welder to do that joint in any position providing the pipe stays horizontal
    If it’s moved to 45° then you’ll need multrun 6G which will cover everything and more.
     
  3. Brad93

    Brad93 M J B Engineering

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    9,030
    Location:
    Essex
    Its a single sided v-prep fillet joint. Partial Penetration.
     
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  4. Richard.

    Richard. Forum Supporter

    Messages:
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    Location:
    Cambridgeshire
    In that case then the correct term is single bevel T joint. I read his description as 2 pipes been joined and miss read the circular disc.
    Because it’s prepped it’s not a fillet and *F codings wouldn’t conform it would still fall under *G codings (groove)
     
  5. paul teggart Member

    Messages:
    19
    Location:
    Dungannon, county Tyrone, Northern Ireland
    Thanks guys. Sorry Richard I should have distinguished the scenario better. We always weld with pipe vert but when the pipe's too long and access to weld it isn't an option, we weld horizontally on a rotating rig like in the picture
    Here's a couple of photos to show what I mean. pipe weld vert.jpg pipe weld hori.jpg
     
  6. Richard.

    Richard. Forum Supporter

    Messages:
    18,350
    Location:
    Cambridgeshire
    Ah ok.
    Yes. Well I can confirm it’s a single bevel T joint your doing if that plate is prepped.
    Because it’s prepped it falls under G codes but the good news is your doing it on rotators by the look of it so you’ll always be in the gravity position so minimum coding requirements for your welders is multi pass 1G.
     
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  7. paul teggart Member

    Messages:
    19
    Location:
    Dungannon, county Tyrone, Northern Ireland
    Thanks buddy much appreciated input.
     
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  8. Mid Wales welder

    Mid Wales welder Welder coding and NDT services

    Messages:
    592
    Location:
    Powys, U.K.
    As Brad and Richard say, it’s a single bevel T joint, as pipe is rotated you can just do this on plate set up as single bevel T. In 9606 the position would be PB and you would get coverage for material thickness and also depth of penetration.
     
  9. Mid Wales welder

    Mid Wales welder Welder coding and NDT services

    Messages:
    592
    Location:
    Powys, U.K.
    Positions in 9606 fall under ISO 6947, so PA, PB, PC etc ;)
     
  10. Richard.

    Richard. Forum Supporter

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    18,350
    Location:
    Cambridgeshire
    9606 it would be PA then.
    Asme 1G.
     
  11. Dimitri De Spiegeleer Member

    Messages:
    179
    Location:
    Belgium
    The 5mm 45° bevel is a bad idea, I bet the root isn't as it should.
    No prep is the most economical solution (and equally good), however whoever decided prep was necessary should've chosen a smaller prep angle.
     
  12. Stingray Member

    Messages:
    464
    Location:
    Northern Ireland
    Used to do a lot of boiler repair work and all single sided full penetration T-Butts were 45 degree inclusive angle, that was according to the WPS, but that’s a bit of a different scenario...
     
    Last edited: Jul 21, 2018
  13. Richard.

    Richard. Forum Supporter

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    18,350
    Location:
    Cambridgeshire
    Full pen yes you need a prep and a root gap. In the OP’s case it’s a prep only half the material thickness and no root gap.
     
  14. Richard.

    Richard. Forum Supporter

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    Location:
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    45° is quite a nice open prep so I wouldn’t be too concerned about LOF in the root. It’s done in position as well and if the welders are worth there salt it shouldn’t be a problem at all.
    A square edged fillet would be more than good enough I’d imagine but there is no harm adding a prep for a bit of deeper pen if the spec requirements suggest it’s there.
     
  15. Dimitri De Spiegeleer Member

    Messages:
    179
    Location:
    Belgium
    weld will bridge in the 5mm wide opening faces. I'd agree if it were larger. Anyway, a 30° bevel (meaning a 60° open angle), less or none at all would be far easier and less prone to root LOF, and cost exactly as much. This is asking for problems, where better alternatives are easily available.
     
  16. Stingray Member

    Messages:
    464
    Location:
    Northern Ireland
    30 degree bevel on your plate is still 30 degrees bevel, it’s not a butt..
     
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  17. Dimitri De Spiegeleer Member

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    179
    Location:
    Belgium
    I guess we misunderstand each other. I agree on both accounts with your post above...
     
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  18. Richard.

    Richard. Forum Supporter

    Messages:
    18,350
    Location:
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    I disagree.
    I’ve seen lots of 45° single bevel T joints macro’d even small ones at 3-5mm in depths and if the welder knows what they are doing it’s a very achievable sound joint. As said above on a single bevel T joint set up at 90° you cannot have an equal inclusive prep angle. A 30° prep in this case would be more likely to suffer LOF problems.
     
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  19. Dimitri De Spiegeleer Member

    Messages:
    179
    Location:
    Belgium
    OK. this is a terminology discussion.

    If the included angle (had to look this one up!) is 60°, would you agree that it is a better/easier geometry to weld than a 45° included angle ?
    20180721152549_001.jpg
     
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  20. Stingray Member

    Messages:
    464
    Location:
    Northern Ireland
    Inclusive angle is the angle of your Joint so two 30 degree bevels on a butt weld shall give you a 60 degree inclusive angle, where as bevel angle is the angle of your prep so a 45 degree angle on a T-Joint still gives you 45 because it’s 45/0 degree, unless you start using j-preps, compound bevels, pipefitters that give you pencil sharpener bevels, that’s a different kettle of fish
     
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