Fluid Pipes can transport any liquid or gas. Use them to connect tanks to machines, or to connect machines to other machines.
Place the pipe down (like any other block) on the side of the machine you want to pump liquids into or out of. Or place it on any side of a Fluid Tank. The pipe will automatically connect to anything it can connect to.
To pump fluids through the pipe: use a Standard Wrench and right-click the pipe block which must become a pump. It will change visually to have a small grey/metal collar. It will pump fluid out of the tank or machine it is connected to. This is also known as the Fluid Pipe being in "pull mode".
Note that the pumping only works properly if your Fluid Pipe system is at least 2 blocks long. So at one end, one Fluid Pipe is pumping liquids out of a tank. At the other end, the other Fluid Pipe is inserting those liquids into another tank or machine. It needs 2 blocks to be able to do this. (One block is in "pull mode" and one block is in regular mode.)
So, this will work OK - the pipes are length 2
That one above is OK but this next one will not work - the pipes are length 1, which is too short