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Long Term Engine Storage 1
- Thread starter swall
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btrueblood
Mechanical
Pat,
Creep is usually a high-temperature concern for steels (it played a part in WTC collapse; it's also a concern for rocket scientists - I used to be in charge of some long-duration testing for an advanced high-temperature rocket engine and part of my duties was to measure the accumulated creep distortion of the combustion chamber).
Technically, creep happens at any temperature above 0K, in any solid material, it's just that at normal temperatures with normal materials, over normal durations, it is negligible. Except when you (a) load steel very close to or beyond its yield, and then (b) hold it there for very long durations (years). Springs that "take a set" are by definition being loaded up to and slightly past yield, so part (a) is taken care of. How long the force is held is the next question, and how much creep would be noticeable is the last part.
Piano tuners worry about it...
Creep is usually a high-temperature concern for steels (it played a part in WTC collapse; it's also a concern for rocket scientists - I used to be in charge of some long-duration testing for an advanced high-temperature rocket engine and part of my duties was to measure the accumulated creep distortion of the combustion chamber).
Technically, creep happens at any temperature above 0K, in any solid material, it's just that at normal temperatures with normal materials, over normal durations, it is negligible. Except when you (a) load steel very close to or beyond its yield, and then (b) hold it there for very long durations (years). Springs that "take a set" are by definition being loaded up to and slightly past yield, so part (a) is taken care of. How long the force is held is the next question, and how much creep would be noticeable is the last part.
Piano tuners worry about it...
To the sagging springs in old cars deal....I do a lot of old car stuff and I must say that I have NOT seen a huge deal with sagging springs. It does happen, but I never put much thought into the reason. It seems more of an individual mfgr problem than a systemic problem. I restored a '37 Buick Roadmaster that was not sagging at all...My 30 Ford is at normal ride ht. Several British cars around here, '58 Morris, 60's era Cortinas, Anglias, MG's and a few Austin Healy Sprites...All without any discernible degree of sag. However, one big Healy and my '59 Nash Met both had terribly sagged rear leaf springs and, my (bought new) '64 Ford Fairlane also had sagging rear springs. Go figure.
Rod
Rod
thruthefence
Aerospace
Gearloose1
Petroleum
As a general rule of thumb, starting it a couple of times a year will hopefully rotate the engine to scrape away accumulated rust and gunk, and also alter the load on all components (e.g. relax springs that were tightly compressed, etc.) and so on.
If you can't start it, even manually turning it over will do the same trick.
Does anyone know what is the protocol for military equipment in long term storage?
If you can't start it, even manually turning it over will do the same trick.
Does anyone know what is the protocol for military equipment in long term storage?
Rod, having owned many '60's Fords with rear leaf springs, I can tell you it was unusual to see one go more than 5 years without noticeable sagging. Mustangs, Falcons, Comets, Fairlanes, etc. Extended shackles to "cure" this were widely available. MoPars weren't a lot better.
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