AS1554-1 vs AS3992

[Flash]

Can anyone give me a reason why AS1554.1 should be tighter than AS3992

R
Flash

[Ron Wisdom]

Hi All,
        I understand that AS1554.1 was initially instigated in the early 1930’s and in recent times has used D1.1 as a guide.
I have used this standard extensively in recent times and would suggest that, if taken literally, is the toughest and most restrictive standard I have used in the past 45 years.

I have often wondered why this is so.

There are a number questions I would like answered.

1. AS1554 does not allow pre qualified single sided butt welds on plate.
    They can be qualified by doing bends.
    Why do we do bends to qualify a weld prep?
    I have witnessed 1000’s of bend tests done for this perpose and seen few fail, always with a weld defect in them detected by the 
    macro.
2. Why does this standard require the former size to change, i.e. 3T to 4T relating to tensile strength.
    AS3992 and ASME9 both state 4T for all materials.
3. AS3992 permits procedures on A1 and A2 materials to 13mm in thickness to be written up on paper without and qualification
    providing the weld preps in the standard are used.
4. In my experience Welding Supervisors with experience are rare.
    I understand by talking to TAFE that there are few courses available country wide.
    Is it because Fabricators place little importance on the welding, but concentrate on the Boilermaking?
   

[Flash]

Hi Ron
the points you have highlighted are very good questions
at the moment we have a series of questions,
I have my own opinions which follow the same lines as you
I hope that some responds that can add a counter view to the debate to make it interesting as that what the forum is all about
R
Flash

[Admin]

mmmmmmmm

[Ballbearing]

Hi Ron,
Will try and answer as best I can.
1  Bend tests for WPS qualification are generally not looking for weld defects, they are checking the weld joint ductility. If a defect is not at the surface or very near the surface it will not be exposed after bending , that is where the macro comes in – identifying internal defects.
Remember – Destructive tests for Procedure qualification (bends, tensiles, impacts, hardness etc) are used to determine the mechanical / metallurgical properties of the weld. With a lot of codes you RT/UT the coupon first so you can find “clean” areas to take your samples from.

2  Higher tensile steels generally exhibit lower ductility so the former size increases as the tensile strength goes up.

3  AWS D1.1 allows the same, you can write up a WPS without any testing (no macro). No idea why AS/NZS 1554 requires it and other codes don’t.

4  At present there are approx 332 holders of AS 1796 and 339 holders of AS 2214 (not sure how many of these people hold both). Not sure if you mean experience as a Welder or Supervisor ? In contrast to Welding Inspection qualifications the Welding Supervisor must have a pretty comprehensive history as a welder before being able to sit the examination.

Hope that helps,
Regards,
BB

[Author]

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