Hello, Just spotted this thread - that's really interesting about the metal fatigue. I'd never considered the forces that the metal dome experienced, thanks for your brilliant investigation!
By the way, it is possible to remove the damper valve from the sphere neck. You have to carefully machine off the rolled lip at the end of the sphere mounting thread. The damper then usually can be pulled out and it renders the sphere much like an accumulator in appearance. I have a couple of 500 cc spheres that were originally CX fronts (75bar) and with their pressure reduced down to 65bar and the damper removed, I have them waiting to be used as main accumulators at a future date.
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