Anyone repair their BRS 3000 ?

[Jerry Adams]

if you buy orings, they normally come in a package with many

you use one, after a time it degrades and you have to replace

what about that package with the rest of the orings, will they also be degraded, or is there a way to store them so they don’t degrade?

(I have a package of orings for msr fuel bottles.  I used one.  The package is degrading right now.)

[Terran Terran]

I hate to needlessly encourage more waste production than necessary. I don’t think it’s a huge safety issue, if you follow a safety protocol.  Clear the area and smell for gas. Sometimes we let our guard down. Test your stove beforehand. Chances are you’ll only miss a cup of coffee. The stove and fuel become useless dead weight in your pack

Depending on the how long and what conditions the extra o rings were stored. I’d carefully examine them. Then test the stove after.

[Brad W]

I want to see if a higher quality-Viton-o ring will help with my gas leakage on the BRS. They don’t have tons of miles but leak while putting on the can more than any stove and when cold way too much for my liking.

[Roger Caffin]

I dare say very cheap crappy O-rings may degrade over time, but I have never heard of either Viton or Nitrile degrading. Bear in mind these two are industrial grades and are expected to last under very severe conditions for years on end.

And I have been buying and using O-rings for decades.

Cheers

[Dan]

The o-rings on the Challenger shuttle were viton, IIRC. Not criticizing the material, BTW. And I understand that the unexpectedly cold weather was a problem. I was skiing in Vermont that day, and it was brutally cold.

[Roger Caffin]

The cause of the disaster was the failure of the primary and secondary O-ring seals in a joint in the right Space Shuttle Solid Rocket Booster (SRB). The record-low temperatures on the morning of the launch had stiffened the rubber O-rings, reducing their ability to seal the joints. Shortly after liftoff, the seals were breached, and hot pressurized gas from within the SRB leaked through the joint and burned through the aft attachment strut connecting it to the external propellant tank (ET), then into the tank itself.
Wikipedia

We do not know exactly how cold the Viton O-rings had become, but they were ‘very cold’. Viton is designed for high temperatures, NOT for use in the cold. Say -20 C to+205 C long term, +250 C short duration.
Personally, I think relying on two huge-diameter O-rings to seal against the temperature range and pressure expected in the booster was ethically unwise, maybe even criminally so.

I recollect from the time that the chief engineer tried to stop the launch for this reason, but the relevant mgr told him to take off his engineering hat and put on his management hat. ‘We have to launch today.’
You see what happens when pollies and bureaucrats ignore STEM staff? Death.

My 2c
Cheers

[Jerry Adams]

“The air temperature was forecast to drop to 18 °F (−8 °C) overnight before rising to 22 °F (−6 °C) at 6:00 a.m. and 26 °F (−3 °C) at the scheduled launch time of 9:38 a.m.”

so, not that cold

but, that case is so different than camping stoves that it probably isn’t very useful.  Larger orings, larger diameter, more force, you could have racking – more force one one side than the other, hot gases,…

the orings on my msr fuel bottles had cracks in them so I replaced.  I bought the bottle in 1972?  probably 30 years later I noticed them being cracked.  But I never noticed fuel leaking out.  No space shuttle explosions or anything

[Dan]

 

Personally, I think relying on two huge-diameter O-rings to seal against the temperature range and pressure expected in the booster was ethically unwise, maybe even criminally so.

The overall system failed, so clearly there were design flaws in this particular case, but huge viton o-rings are still used for this application, so I think this is an over-reaching generalization made by someone who is probably not an aerospace engineer. It’s easy to mock engineers and managers retroactively, but the people who designed the space shuttle were not stupid.

[Roger Caffin]

but the people who designed the space shuttle were not stupid.
Oh, for sure, I agree.
But it still blew up.

Cheers

[Dan]

But it still blew up.

Yes it did. And may their memories be a blessing to their families.

[Author]

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