Friday, 16 January 2015

Q:- When performing side bend tests for procedure qualification or welder qualification under API 1104, is it acceptable to oxygen cut the side bend specimens to 1/2" width?:

Q:- When performing side bend tests for procedure qualification or welder qualification under API 1104, is it acceptable to oxygen cut the side bend specimens to 1/2" width?:




  • Andy Clendenin
    Andy
    Andy Clendenin
    Qualified Welding Inspector & AWS CWI
    Yes of course you can cut the straps with oxy acetylene or any way that is easy, and then smooth them with a grinder or sanding pad or such. I believe there is a diagram in the code book. Should round the edges or corners slightly too. ASME or API
  • Matthew Freeze
    Matthew
    Matthew Freeze
    Quality Professional
    I am being technical, but I disagree. But the only danger is oxygen cutting the side bends is when dealing with non-carbon steel. In my interpretation, AWS D1.1 and API 1104 prohibit oxygen cutting side bends to 1/2" width. Per those codes, you must oxygen cut specimens to 3/4" width and then machine them to 1/2". ASME Sec. IX allows it only if the metal is found in P No. 1.
     Andy Clendenin likes this
  • Andy Clendenin
    Andy
    Andy Clendenin
    Qualified Welding Inspector & AWS CWI
    Ya trying to cut stainless with a oxy acetylene torch is a little messy at best. But I have cut carbon steel pipe personally many times with a torch and cleaned up with a grinder, and never had any problems. Plus a couple times the Co. required no clean up after cutting with a torch, Face bends root bends and even side bends. But I know some are not quite so technical on the ROW. But no mater how you cut and clean and machine the minimum is the important thing here a 1/2 inch SB, or 1 inch FB or RB. Plus of course the 1 1/4 inch wide fillet weld on the branch.
  • Jon Bosley
    Jon
    Jon Bosley
    Welding inspector AWS-CWI Currently looking for next project
    Why ask the question if you know the answer? Yes you may oxy cut to 3/4 then machine to 1/2. And if it's stainless just machine cut it gives both options. Per API 1104.
     Mike Horton, Andy Clendenin like this
  • Matthew Freeze
    Matthew
    Matthew Freeze
    Quality Professional
    I know what is written in the code. I'm seeking opinions regarding the interpretation.
  • Jon Bosley
    Jon
    Jon Bosley
    Welding inspector AWS-CWI Currently looking for next project
    I guess I'm having a hard time understanding what's left to interpret?
  • Donald F. Jenkins III
    Donald F.
    Donald F. Jenkins III
    Contract Inspector: AWS-CWI; MT Lv. II; UT Lv. II
    Would this be the requirement outlined in the notes of figure 4.13 (AWS D1.1 2010)?

    Figure 4.33 allows for grinding (as opposed to machining) on the reinforcing welds and backing strip. Root and face bends allow for thermal cutting and grinding.

    I haven't found anything which definitively prohibits grinding on side bends, but that gets into the fallacy of proving a negative. Everything I have found in the D1.1 for welder qualification points back to sec. 4.9.3.1 and figure 4.13 which explicitly states machining. I would interpret this in the realm of AWS "shall:" statements and err on the side of caution.

    Perhaps a bandsaw would provide a better means of extracting the side bend specimen. There are some good port-a-band(saw) products out there, that might get you there in the field depending on diameter and thickness.
  • Keith Proctor
    Keith
    Keith Proctor
    AWS Certified Welding Educator
    I’m more familiar with D1.1. It does allow for the edges of face and root bend specimens to be thermal cut or by any convenient means. These edges will not be placed under tension and will not be part of the convex surface under examination.

    Side bends are different. If you thermal cut these specimens you are introducing a HAZ into the area of interest. The Code says to leave 1/8” on either side to remove by grinding or machining thereby removing this HAZ.

    Thats how I interpret it. Any thoughts?
     William Komlos likes this
  • Donald F. Jenkins III
    Donald F.
    Donald F. Jenkins III
    Contract Inspector: AWS-CWI; MT Lv. II; UT Lv. II
    I dug up my API 1104 and found a more definitive answer for the question in the original post.

    Sec. 2.6.5.1 Preparation
    Side bends...shall be machine cut, or they may be oxygen cut to approximately a 3 / 4 -in. (19-mm) width and then machined or ground to the 1/2 -in (13-mm) width. The sides shall be smooth and...

    That means it is not acceptable to cut the side bend specimens to 1/2", Kieth Proctor hits the nail on the head.
     William Komlos likes this
  • Robert Mertz
    Robert
    Robert Mertz
    ASNT NDT Level III & SCWI at Alta Vista Solutions
    Keith provided not only the right answer but also the reasoning and/or logic for the requirement. I was glad to see the mention of different requirements for root & face bends. That may be why some may question the difference between side bends and root and face bends.
  • Ledon Watkins
    Ledon
    Ledon Watkins
    Associate Instructor at Hellier NDT
    The only danger with torch cutting is with high alloy and tempered materials. The high heat input can change many mechanical properties which could fail a procedure qualification. Generally torch cutting is limited to mild steels with adequate carbon content and lower alloys. High alloy materials such as High yield steels and stainless do not react well to localized heating.
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