Feynman s famous c clamp experiment.
Challenger o ring material.
Fkm is the short form for the fluoroelastomer category according to the american standard astm.
January 24 1985 shuttle flight that exhibited the worst o ring blowby.
The material of the failed o ring was fkm which was specified by the shuttle motor contractor morton thiokol.
In the parker o ring handbook ord 5700 paragraph 4 0 says it has been said that o rings are the finest static seals ever developed perhaps the prime reason for this is because they are almost human proof.
Number of o ring incidents vs.
Feynman now believed that he had the solution but to test it he dropped a piece of the o ring material squeezed with a c clamp to simulate the actual conditions of the shuttle into a glass of ice water.
If the gland has been designed and machined properly.
The disaster of challenger mission sts 51 l was the result of human engineering.
August 19 1985 nasa level i management briefed on booster problem.
Joint temperature incidents when o rings failed source.
The joint failed because at cold temperatures the silicone o ring material lost its resilience and took a set.
Report of the presidential commission on the space shuttle challenger accident 6 june 1986 volume 1 page 145 link color added.
The temperature at the time of the challenger liftoff was 32 degrees f.
Then when the the booster was lit and is casing expanded the o rings retained their cold compressed shapes and allowed hot gas from inside the casing to spurt out the resulting gap in the seal.