AirTech wrote:
I use copper regularly on 100psi - most air operated control valves are plumbed with hard drawn copper tube as standard, stainless tube is used where corrosion requires
it. (Tubing is more leak tight than screwed steel pipe).
Most people think of air operated hand tools, air operated machine tools are also possible and more common than most people think. Rotary seals can be made quite effectively with graphite running on honed hardened steel (although these days stainless is more common). Basically the point I am making is that if you cant have hoses then it is still possible to achieve the same result in a large number of other ways. (BTW dentists and surgeons used to use air drills on flexible jointed arms because you couldn't sterilize rubber hoses without damaging them.)
Well, my speciality is high pressure hydraulics (6 000Psi and above), but I've used quite a lot of pneumatic too.
The hard drawn copper tubes you were speaking of are afaik, usually copper beryllium alloys not straight copper. The latter in metallic form is both toxic and hard to separate from its compounds in a process involving fluorid acids. As such, it is unlikely it is used already on Safehold. Beryllium greatly improve tensile strength of copper even as a trace element at less than 1%, and even allow static tempering to form springs (but usually in bronze alloys not straight coppers). Straight copper is great for water and very low pressure applications.
Using brass is cheaper at this point I think.
As for rotary joints, yes they are possible, but costly.
however, with air (not oil), a multi layered etremely fine weave silk tubing can be used if the outer layers are waxed. Not ideal as it will be at least a bit leaky (meaning power losses and limitation to flow) but Safehold has a much better silk than Earth. Probably quite costly too