Quality Engineering and Construction from Wally World

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09-24-19, 07:12 PM

#26

JanMM

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Helmet on head when it happened?

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Bacchetta Giro A20, RANS V-Rex, RANS Screamer

09-24-19, 10:14 PM

#27

boilermaker1

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Quote:

Originally Posted by Notso_fastLane

It's probably not the thickness of the wall/weld.

After welding any metal (Ti, Al, or steel), unless it's non-structural, and very very few exceptions, there needs to be a post weld heat treat/stress relief, or the weld process itself actually weakens the metal locally.

Not really. IME most steels are just allowed to cool. Some alloys need preheat and stress relief but though not uncommon it's not that common either, especially in structural steel such as plates and beams, even stainless. I'm talking about welding in industrial construction and maintenance including refineries, steel mills, water towers, smokestacks, storage tanks, chemical plants and both fossil and nuclear power plants.

Lots of high pressure ASME code work on pressure vessels and boilers. Welding to the highest standards, often 100% X-ray. Mostly stick and heli-arc. In all positions; lots of overhead and quite a bit of mirror and blind welding--looking through the root from the other side. You can't roll a boiler superheat section or an MSR in a nuke.

I don't know the aircraft industry. I assume it's stringent.

Last edited by boilermaker1; 09-24-19 at 10:25 PM.

09-25-19, 03:55 AM

#28

_ForceD_

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Quote:

Originally Posted by Troul

i'm not shocked, not shocked at all..

I see what you did there.

Dan

09-25-19, 03:59 AM

#29

_ForceD_

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Quote:

Originally Posted by cyccommute

Steel tubing for bicycles is around 1mm thick. The tubing in the picture looks like it's in that range. I think the problem is that they cut out the hole for the shock mount. I would assume that most mounts like that are welded to the tube without cutting a hole in the tubing. For a really cheap HelMart bike, I would think it would be cheaper. Cutting tubing is an extra step and you have to weld all the way around the mount as well as align it.

That's what I'm thinking too. But, perhaps the cutout, and the bracket on the shock, is so that it will be held in precisely the correct place for the weld to happen. And thereby making fewer mounting weld errors, and cheaper in the long run.

Dan