You should be able to extract from the tanks using pipes of choice (although they won't do so automatically), but you can also hook pipes up directly to the smeltery drain. Not the faucet, but the actual drain block. For instance: for my bulk casting jobs, I use translocators from the drains into the tables/basins (faster than faucets and don't need to be clicked on every time). Nothing keeps it from going somewhere that isn't a TiC container, but the transfer mechanism should be attached directly to the drain block.Quote from CNCRaymond
Is there any way to move liquids out of the smelter using pipes into railcraft tanks? I had some resonate ender and for the life of me I cannot get it out in liquid form to any tank other than the Tinkers tanks which will let liquid in from Thermal Expansion (164xx) but won't out put it to thermal Expansion machines.
You can also put a BuildCraft tank under the faucet and pipe out from it as normal. If the drain is on the lowest level of the smeltery, you could even output into a RailCraft tank right under it, but that's probably not practical.
If something doesn't want to flow through a given pipe, I'd think that to be a problem with how the pipe handles fluids - but given the fluid changes in MC 1.6, as far as I know that should never be an issue.