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Is this different than oil pipelines because of the low pressure and lack of a heat transferring medium to even the temperature of the tube?Most hydrocarbon pipelines run HTHP: high temperature, high pressure. This keeps their contents viscous. That, in turn, means heat emanates relatively uniformly from inside the pipe. For pipelines subjected to asymmetric expansion (e.g. when starting up or shutting down), they "walk".
"Walking behaviour occurs as the pipeline is heated, and expands asymmetrically, until the point when pipeline expansion is fully mobilised. Expansion is ‘fully mobilised’ when a virtual anchor forms near the centre of the pipeline. The virtual anchor is then stationary, while pipe to each side expands away from the anchor as the temperature continues to rise. Once expansion is fully mobilised, walking ceases for that cycle." [1] As long as it walks laterally, pipeline owners tend to be fine with it
The solution to walking is typically laissez faire (taking care to ensure the deformation occurs laterally, i.e. side to side, versus sticking a butt up into the water.) Needless to say, this isn't an option for the Hyperloop.
Granted, the contents of these pipes operate at 130º to 170º C. They're also narrower, resist a smaller pressure differential, face fewer such asymmetric events and don't face the stress of capsules periodically whizzing past inside them. Our tube won't displace by meters. Its displacement, moreover, won't be problematic on day one. But over time it will critically weaken known materials. Big, dynamically mechanically stressed, close to vacuum and above ground is hard.
[1] https://www.researchgate.net/profile/David_Bruton/publicatio...