I have fluids disappearing between factories.

It started with a factory producing oxygen. Oxygen was piped into a bulk input pipe inside with a bulk output pipe outside on the matching port. The port was set to output mode. The oxygen went into the input pipe and disappeared as it was transferred to the output pipe outside. It was supposed to go into another factory with the opposite set up but no oxygen ended up in there. The oxygen just disappeared. It was fixed by using a different port on the oxygen factory.

Now I have molten iron and molten steel disappearing. Two factories, one producing molten iron and the other molten steel. The fluids are disappearing. I tried replacing the buildings that use the molten metals with storage tanks so I could see if they started filling but they never did. I've lost a lot of iron and steel plates now.

I will start replacing all my fluid connections with barrels but that will take room from each factory. Once I have the resources I'll make bigger factories and put the whole process inside a single factory but for now it's easier to use a bunch of small factories.

The fluids don't seem to be disappearing from factories where the input/ output pipes don't run dry. The factories that filled large storage tanks before piping their fluids out haven't had any issues.

The process is external ores -> crusher factory -> sorter factory -> processing factory -> blast and induction factory x> casting factory. Fluids are only transferred between the blast/ induction factory and casting factory, everything else works.

I'm not sure what causes this. The factories where fluids are disappearing were working for a while before the problem started. I noticed their outputs stopped so I increased the ores going into the first factory but nothing changed. I built storage tanks to test the liquids being transferred but they never filled with the disappearing fluids.

Fluids are still transferring just fine in my game. Could you provide a way to reproduce this bug, using cheat mode or creative mode or editor mode?

I tried reproducing the bug in cheat mode but everything is transferring how it is supposed to. I even tried putting the factories under stress with a lot of items and fluids being transferred around.

If I find the bug again while playing I'll try reloading the save to see if it still occurs, if the bug persists then I'll share my save with you so you can observe it.

Thanks anyway. I love your mod!

Thanks! I appreciate it.

I have seen that pipes seem to stop showing fluid transfer when transferring between factories but the fluid still seems to be flowing.

"I built storage tanks to test the liquids being transferred but they never filled with the disappearing fluids."

When I attempted to recreate the bug I saw the fluids appearing between factories for a moment.

I have experienced this as well now a few times.
The intermediate pipes just suddenly stop transferring fluids though the input pipe on the other pipe is still draining everything into the void.
Ok seems like I have a world with a spot where this happens frequently now.
It is some fluid from outside, which pulses due to slow production. Then I have a medium factory where I pipe it in using input/output pipes. The output pipe is 5 blocks away from a second input pipe which goes into a smaller factory. Inside of there is another output pipe, followed by a pump and 3 storage tanks (pressure ones from angels). The fluid stop flowing from outside into the first factory and never reaches the tanks in that case.

After testing a bit it seems to happen as soon as the pipes inside the first factory connecting to the second input pipe (to the recursed factory) are completely drained and not showing any fluid in them. They never fill up again but on the input side on the outside fluids are still disappearing.

I'm trying to reproduce your issues by rebuilding your setups, but with no success so far. Could one of you maybe upload your save somewhere, and provide a link and description where to find the buggy connection?

I switched all my pipes to balance mode so they won't run dry and removed the pumps from the output pipes. In some spots I put small tanks, like the inline tank, in between the output and input pipes between factories to further ensure the pipes won't run dry. I couldn't reproduce the bug and I haven't seen it again since.

Set the input to balance and very fast update rate. That pretty much instantly caused the bug.
I noticed you just need to drain the pipe very quick via another factory input pipe.

See here for details: https://imgur.com/a/pljzz1N

I can also confirm this. In my Seablock world, I have been losing sulfur in the crystal slurry/waste sulfur loop, which should be a net positive. I began losing less when I removed one underground that was no longer needed in the waste sulfur water pipe (between factories) but somewhere, there is a loss.

I have uploaded my save file to https://www.dropbox.com/s/nk9e70askrqi4kr/SB3%200048.zip?dl=0

Alright, thanks. I'll see what I can do, in the meantime I suggest you avoid balance mode.

Jemsterr, I've looked at your save and there's no fluid being lost at all. It just seemed that you're losing sulfur because your sulfuric acid pipeline hadn't filled up yet.

Keridos, I'd like your save please.

Cant give you a save since I deleted it and restarted a new save. If I encounter the bug again, Ill post here

I have experienced this as well. It doesn't seem to be easily reproducible. Once it happens, the only fix is to pick up the transfer pipe and replace it.

I have seen where it seems like fluids aren't being transferred but actually are, but this isn't that. It can be verified by twisting an underground pipe later in the sequence to verify that the pipes aren't filling up. I've noticed that it either usually or always happens in the output pipe. I have a save file and a video.

There is definitely something.. I was producing enough oil to run my boilers from 10 mk. I farms with pips filling up a warehouse.. I upgraded them to Mk II which doubles the output and put each step of the process in a factory building... Now I'm running out of output. I even built another 10 farms, and the oil is just not enough. The pips (purple oval shaped icon) should fill the chest, but they are slowly draining away.

I changed over to normal pipes instead of the input/output pipes, and the problem went away a little, but I just changed back - so you will have to wait a little for the pipes to refill to actually see it, currently, the presses are just chewing through the pips while the pipes fill back up with their 2500 each.

(Ignore this save) Savegame: https://www.dropbox.com/s/gz1r9swkru1v7r4/SB3%200082.zip?dl=0

Edit to add: I switched over to barelling most fluids after my last comment, and straight away, my sulfuric waste water overflowed. I might try barrelling here and see what happens. (And in answer to your reply, yes, the sulfur gets used up while the acid is being made, then it refills when the sulfuric waste water is processed. Over time, the amount of sulfur increases dramatically... But it was consistently draining. I was thinking of installing creative mod for the empty barrels and having 2 savegames you could compare, ore with barrels and one with your high-flow pipes).

Edit edited to add that something I did before that save fixed it - possibly replacing pipes? I can't reproduce it now.. weird. Even looked through the factorissimo code to see if there is an issue there, but it's pretty straightforward - maybe a factorio fluid rounding error on the transfer function? That same error that causes pipes to have 39.999 of a fluid instead of 40?? Wish I could help troubleshoot better.

Not sure if this will help much...
I normally run regular pipes for Factory transfers and ensure that input and output are set correctly.
I noticed that balanced mode seems to "Void" some of the liquid transfer at odd intervals.
For me it was almost unnoticeable unless I put the system under stress.