>
> Second, I did not say that the welds were bad from manufacture or defective at manufacture. Actually I would advise against assuming the problem
> was a defect. Especially with the need to err on the side of caution if only cuz we're talking about highly combustible stuff, not to mention 40
> years is a lot of contracting/expanding and bouncing. Moreover, putting another 40 year-old LP gas 60lb. bomb-equivalent to replace mine seemed
> illogical to me. Additionally, I want the motorhome to be the best condition I can, not just for my time using it, but also for whoever else drives
> this in the next 40 years.
>
> david
David,
I know you did not say that the weld was bad at manufacture. I said that. I wrote that with good reason.
If you are correct and the tanks has failed (cracked) at the weld or where it should have been welded, it was a defective weld. That is all there is
to that.
A properly done weld should be as strong and tough (two different things) as the parent metal. This is both an ASME and ASTM standards. I have done
tests to the welds in super-critical (steam reference) power plant welds to prove this. This is not nearly a unique situation.
Welded assemblies can fail. 45 years ago I supervised the assembly of the DECO Monroe power plant. It was designed for a 20 year life. It is still
on line, but five years ago the reheat piping was replaced with drawn tubing. It was originally seamed. While the field welds were no issue, the
seams were machine welded and an ultrasonic inspection showed cracking starting in the root of the welded seams on some sections. This was no
surprise to me because the X-rays of the welds that I certified frequently showed poor root fusion. They were defective 45 years ago and only had to
be heated to 1005°F about 200 times with 500 psi steam to start cracking.
Matt
--
Matt & Mary Colie - '73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Still Loving OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Twixt A2 and Detroit
> Second, I did not say that the welds were bad from manufacture or defective at manufacture. Actually I would advise against assuming the problem
> was a defect. Especially with the need to err on the side of caution if only cuz we're talking about highly combustible stuff, not to mention 40
> years is a lot of contracting/expanding and bouncing. Moreover, putting another 40 year-old LP gas 60lb. bomb-equivalent to replace mine seemed
> illogical to me. Additionally, I want the motorhome to be the best condition I can, not just for my time using it, but also for whoever else drives
> this in the next 40 years.
>
> david
David,
I know you did not say that the weld was bad at manufacture. I said that. I wrote that with good reason.
If you are correct and the tanks has failed (cracked) at the weld or where it should have been welded, it was a defective weld. That is all there is
to that.
A properly done weld should be as strong and tough (two different things) as the parent metal. This is both an ASME and ASTM standards. I have done
tests to the welds in super-critical (steam reference) power plant welds to prove this. This is not nearly a unique situation.
Welded assemblies can fail. 45 years ago I supervised the assembly of the DECO Monroe power plant. It was designed for a 20 year life. It is still
on line, but five years ago the reheat piping was replaced with drawn tubing. It was originally seamed. While the field welds were no issue, the
seams were machine welded and an ultrasonic inspection showed cracking starting in the root of the welded seams on some sections. This was no
surprise to me because the X-rays of the welds that I certified frequently showed poor root fusion. They were defective 45 years ago and only had to
be heated to 1005°F about 200 times with 500 psi steam to start cracking.
Matt
--
Matt & Mary Colie - '73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Still Loving OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Twixt A2 and Detroit