[kenned3]

non-metals have their own problems and glass tends to have some really weird properties.

I would think a major one would be their failure mode. Metals flex and expand before they eventually fail. Glass/ceramic is fine until suddenly it isn't and has a total failure.

Think of a window being hit. If it were metal it would probably deform but if it is glass it shatters.

Next would be joining them on-site. If needed, metal piping can be bent and welded in-place. what do you do with a glass pipe that needs a join? what do you do if there is a small variation in the plans and the pipe needs an adjustment?

I think there are a host of reasons why glass is not used for pipes.

[mulmen]

Glass is already basically welded, or maybe it's more like brazing. But an oxyacetylene torch can be used to work with glass just as well as to cut or weld metal.

Metals also have weird properties. Like tempering and hardening based on temperature. In an industrial setting you need expert welders with deep knowledge of the materials or a weld is going to fail and ruin your day.

So it doesn't seem like a huge leap to me actually, assuming ceramics or glass actually have desirable properties.

[kennend3]

I noticed you focused almost exclusively on the welding while ignoring the brittle nature of glass?

I would think that putting liquid salt in a a glass pipe is somewhat asking for trouble. One of the many issues with glass is "thermal shock".

Let's say there is a fire and water based sprinklers are activated.. what will the 1,400F glass do once water touches it?

Or there is an accident and someone bangs into the glass. Metal can deform and not fail, glass cant.

[werdnapk]

Doesn't glass.... melt?

[systemvoltage]

Composites? Such as the stuff used in Aviation?

[PaulHoule]

Most of those contain plastics which are usually not good for high temperatures but also have long chain molecules which get broken by neutrons and other particles and cannot heal defects the way metals can.

[Turbots]

what about glass pipes encased in said metals :-)

[HPsquared]

Glass-lined vessels and pipes are already used in the chemical industry so it's a somewhat proven technology.

Not sure if it's suited to the chemistry and temperatures (and radiation) of a molten salt reactor, but it seems like an interesting technology.