Factorio Forums

Chemical plants with extremely high production and consumption rate aren't able to keep up even when directly inserting into eachother, for example this setup does not seem to keep the water chemical plant running at all times, even though the one behind is producing more than twice as much steam as needed (and says "Output full"): Expectation:
Fluid flow between directly-connected building should be uncapped, regardless of max flow rate of pipes.

Result:
It is impossible to feed machines that use fluid at over a certain rate. (the cap seems to be around ~7500 fluid/s)

How to replicate:
Setup a chemical plant with legendary speed modules and beacons, using a recipe which utilizes fluid and feed it from another chemical plant right behind it.
Or use this blueprint in the editor.

Machines are limited to 100 fluid per input/output operation. Pipes have no limit for total flow.

Yeah, that's what I've gathered, it seems strange since it is now possible to make setups that vastly exceed the limit in vanilla (or rather, the dlc) without the use of any external mods. If this is intended then maybe the speed of entities that use fluid should be capped to give some feedback to the player of what's happening.

As was mentioned, the absolute max for a flow operation is 100, or 6000/s. However, this breaks the "it just works" mantra of the new system. I am thinking of ways to fix this.

For now, if you place a pipe which connects both fluid ports on both machines you will be able to double the throughput.

any updates on the matter?

This is going to remain unchanged in 2.0, since any changes around this will break factories. I will implement some changes in 2.1 that should make this situation better.

thanks for this update

Setup on the left produces 6122 molten iron per second. Identical setup on the right produces 5769 molten iron per second. We get 6% more output if we unsync productivity bonus from normal production cycles

edit: I fixed it by making foundry output buffers a lot bigger (2x2000), now I can get full output out of foundries without constant flickering: https://mods.factorio.com/mod/foundry-output-buffer

Bigger output buffers help, but you can still get situations where you can't quite get the full 100/tick out of a connection. There is a formula for the flow per connection here (as well as a description of the exact behavior of the fluid count in the output box).

Ultimately, in the current version, the only way to get a full 100/tick from a connection is to have the machine start full, and a recipe that produces 100 fluid every tick (or a clean factor of 100, and enough prod to make 100 per tick). And even then, it'll only work for one connection, or until the target fluid network is not completely empty. At that point it'll get off the 100 refill/100 drain cycle and give a lower output on average.

I saw that there are plans to fix this in 2.1, which sounds great! The idea I came up with that felt simple from a user perspective (if not necessarily from a dev perspective) is to have the fluid output pressure not be the fraction of the fluid box that is full, but instead MIN(1, box contents / (box size / 2)). That way as long as the fluid box is enough to store more than 2 crafts of the recipe (2 * recipe size + plus 100 * the number of connections), you will still be draining at full speed when the machine has room to complete another craft and fill the output box back up. One could imagine a similar behavior for input boxes, though I think for those increasing the fluid box size with machine speed (as was just implemented) will probably be enough. But whatever the fix looks like, I am looking forward to it!

I recently run into this "issue" when building final setups. Just to make things clear.

This setup limit is 6K/s per input pipe (hardcoded limit??), so description with 180K/s steam converting to 16K/s water is wrong.
Same applies to output pipes, so how can I calculate production if limit of the input fluids is 18K/s ?

This also affects pumpjacks with legendary beacons or high productivity, making high mining productivity research quite useless for oil (It cant output whole 2.2M/s just 6k/s)

In the endgame, for players who like to use maximum speed beacons and productivity modules, this issue impacts almost every building that uses liquid inputs/outputs.


I'd also add that the fluid system makes it really difficult to control speed on very large space platforms. I've found it to be a real struggle to get legendary pumps to keep thruster pipelines completely filled with thruster/oxidizer. When the pipelines get very large, it's hard to pump fluids into them.