Ever had O-rings fail in brief dry storage?

[Packard V8]

While doing a major plumbing revision, I took the water softener out of service and set it aside. Two weeks later, I reinstalled the water softener and had major leaks between two sections sealed by O-rings; sections which had NOT been disassembled and which had been water tight for ten years.

Now, I've had gaskets dry out and shrink while in storage, but these were nitrile O-rings which are still supple, no cracks. What are your thoughts?

I went to my 342-piece O-ring kit and everything in the correct diameter was too thick in cross-section. I didn't have a metric O-ring kit.

Speaking of time and place utility, I tried hardware stores and bearing supply stores with no luck. On line, the kit was $4.50 for three O-rings, two kits required. No problem, we can handle $9; but with tax and shipping, it's all of a sudden $22 for six O-rings. Last chance locally was House of Hose. They had the needed O-rings for $2.50 each, $16 total.

Now, it's reinstall and hope the new O-rings are magic.

jack vines

 

[The Cobbler]

they likely formed to a given pressure & angle from years of service, now you've disturbed that , they no longer have the same memory to go back to their original shape , so they leak

 

[Packard V8]

Yes, No, Maybe. The two sections were tightly bolted together and were not physically disturbed.

jack vines

 

[claymont]

I've had decent results on eBay. I make sure to eliminate overseas sellers and try to buy from sellers that sell commercial or industrial products for the most part. I try to get them with free shipping if possible.

 

[alfadan]

Is this a well or municipal/rural water? I think chlorine plays havoc with rubber orings and seals.

 

[BrandonV]

Major plumbing revision? Enough to where the pressure changed?

 

[nadogail]

New O rings can be kept in storage for years, if properly packaged; used O rings should be replaced after being disturbed.

 

[Packard V8]

used O rings should be replaced after being disturbed.

Agree, but these were never disturbed. Might be a mystery never to be solved.

I think chlorine plays havoc with rubber orings and seals.

City water, but there was no visible deterioration; all six O-rings were still soft, supple and round.

jack vines

 

[MovingAlong]

Yes, No, Maybe. The two sections were tightly bolted together and were not physically disturbed.

jack vines

The bolts were not disturbed on the outside, but you did cycle the pressure... o-rings are internal and would have contact with the pressurized water. Why else would there be o-rings?

But yeah, without pictures it's hard to imagine. (pics wouldn't actually help, but our guesses might be more abundant)

 

[finn]

They took a compression set, and disassembling the joint disturbed them, by definition.

without measuring them, you can’t definitively say they were still round. Same for “supple”. You need to put numbers on these observations, ie durometer, cross section diameter, etc if you are interested in the forensics of the failure.

did you check for scale or debris on the sealing surfaces?

Forensic failure analysis was always the fun part of going to work. The answe to the riddle is there somewhere

 

[Packard V8]

So the new O-rings sealed perfectly; no leaks.

jack vines

They took a compression set, and disassembling the joint disturbed them, by definition.

without measuring them, you can’t definitively say they were still round. Same for “supple”. You need to put numbers on these observations, ie durometer, cross section diameter, etc if you are interested in the forensics of the failure.

did you check for scale or debris on the sealing surfaces?

Forensic failure analysis was always the fun part of going to work. The answe to the riddle is there somewhere

Agree, there's always an answer somewere, but it's not visbile to experienced plumbers. One more time, the O-rings were sealing perfectly in use. When the water softener was taken off line, the joints were not disturbed at all and the unit was handled carefully. When reinstalled, the O-rings leaked profusely. Upon disassembly, a careful inspection did not find any corrosion, scale or debris or any visible problem with the O-rings.

The good news is the new O-rings sealed perfectly.

jack vines

 

[finn]

So the new O-rings sealed perfectly; no leaks.

jack vines

Agree, there's always an answer somewere, but it's not visbile to experienced plumbers. One more time, the O-rings were sealing perfectly in use. When the water softener was taken off line, the joints were not disturbed at all and the unit was handled carefully. When reinstalled, the O-rings leaked profusely. Upon disassembly, a careful inspection did not find any corrosion, scale or debris or any visible problem with the O-rings.

The good news is the new O-rings sealed perfectly.

jack vines

We would measure durometer, look at the surfce under microscopes (likely scanning electron microscopes).
, section the rings and use optical tools to campare, etc.

Not something you’re likely to do at home.

It always helped to have a gasket and seals engineer on staff, and direct access to the supplier’s engineering team.

Without those tools, it’s somewhere between a guess and witchcraft.

Like I said, forensic engineering is somewhat of an art. It involves establishing methodolog, looking for what’s different than the norm, and asking questions.