I am so far out of touch on expansion tables that I cannot give a figure but the posts of others seem reasonable in the order of a few metres.
(By the way the reason that modern railway lines do not heat buckle is that the final welds are done at high atmospheric temps, so they are normally under tension. This is not possible underground.)
I fear that the practice of cementing the casing at the bottom has left the surface as the only expansion point available.
An answer may be to seal at the surface when the pipe is hot by putting a sleeve between the pairs of casing to minimise flow and them somehow welding this to the pipes while they are hot for a final seal. This would then put the pipes under tension for any future cooling in a close down. The pipes should be able to handle this.
Maybe future wells need to have an expansion sleeve arrangement incorporated into the bottom casing length as it is cemented. This may allow for future expansion.
Just an idea. Comments please.
Regards
RB
RNE Price at posting:
$1.10 Sentiment: LT Buy Disclosure: Held
