strip passes TIG pipe girth weld

Are strip passes considered good form when girth welding pipe - V-groove - 5G (PH) ? What are the "rules" for them?
Example would be a stainless steel pipe TIG weld around 22mm wall thickness steel pipe therefore 20+ weld runs, can be good to get things back to uniform height as approaching cap.
"strip passes" - part-circumference weld runs - not a complete pass.
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wrote:

Not sure about your terminology. The only time you do continuous weld beads around a large pipe is when it is on a rotator or on rollers. In the field you are breaking up the weld passes as position and fit-up require. Also you don't usually switch from vertical up to vertical down on the same weld pass.
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Hi Ernie - oops - completely messed up this one in the telling...
Trying again
No matter how you lay up the weld runs - 1G-rotated, 5G-up, whatever... Suppose you would have 27 runs - but you've ended up with a sector of the circumference which is less high than other parts (yes, for the same number of runs they whould have filled the groove to the same height, in an ideal world - but sometimes things are not so ideal). So before you get the the capping passes you do say a layer which is the full of the groove comprising several runs - but these runs go only say half way around the circumference...
With the intention that entering the capping pass, you have a uniform groove fill level - normally just below the pipe outer surface level.
So for one thing, that makes the number of runs in a pipe girth weld difficult to represent in one cross-section.
Now I know you are so skilled that this never happens to you... But it can happen to less experienced welders - you will have seen this(?)
I gather part-circumference runs are known as "strip" or "stripper" passes.
???
Rich Smith
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wrote:

I spend way more time inspecting pipe welds that running pipe welds. Monitoring your overall weld bead height is just something you have to keep track of. You can adjust your bead height by changing your travels speed. As an inspector I don't care how many passes you have in the groove. I care what your root looks like, and I care what your cap pass looks like. On steam lines I will mag particle your root to look for cracks, and I will mag your cap. If you have 23 passes on one side and 19 passes on the other does not matter to the code or to inspection. That is a personal thing, but is not important to whether or not your weld is accessible.
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For some alloys - like duplex stainless steel or Ni-alloys - you are tightly bound by your heat input and it would not be a good idea to try to change bead height by significantly changing travel speed? I have seen that with duplex you have to get going and stay going at that speed you know you need... Of course, different fill in different sectors of the circumference means that you are making a systematic error going faster in one sector than another (if speed change were random, the different bead sizes would cancel eachother out(?)).
I note your point - for sure you cannot inspect how many runs there are between root and cap for a production weld which cannot be destructively tested (eg. section and macro-etch) - nor does it matter metallurgically so long as you have always stayed within close limits on welding conditions...
Thanks and best wishes
Rich
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