Reason:
So i've decided that for my new furnaces i want a setup that require me to be able to fill 2 blue belts per side of a train wagon. I've searched all over the place and have found not a single solution that does this, which i find ...unlikely. Someone surely must have done this before? But i couldn't find anything so i had to design my own. Using the numbers kindly provided by https://dddgamer.github.io/factorio-cheat-sheet/ i came up with two different methods to achieve two fully compressed blue belts.
Lo and Behold: Method 1: Weaved underground belts (bottom of image)
This one is quite simple, it uses a weaved red underground belt to transport the input of the lowest inserter, a red belt is barely enough to handle this. The rest is straight forward two pairs of inserters load on two belts, which are merged into one at the end-splitter. The only "drawback" is that it's not symmetric.
Method 2: Circuit-timed inserters (top of image)
This one uses a clock to time inserters so that two adjacent inserters can fill one lane of a belt, it's shorter, but does not deliver full performance until all 6 buffer chests have enough content (they're limited to one stack each). It's symmetric though, and i've always wanted to try timed-inserters =).
Challenge:
As this was my very first attempt at this i'm sure there must be better, more compact layouts for this. Or layouts that simply look nicer. So i challenge everyone who want to try to provide me with a better layout for my base. I'd be really greatful for any input ;).
The rules are:
- Vanila only. No mods, no loaders. (Except for the demonstation loaders ofc...)
- Must be tilable for long trains and have one space every 7 blocks (inbetween wagons) to fit a signal.
- Must provide a way to tunnel at least one belt per wagon to the other side of the track. (Doesn't have to be a full free row, undergrounds are fine)
- Must unload 4 fully compressed belts (2 per side) from each cargo wagon.
- Bonus points: Has 6 buffer chests per side directly loaded from the wagon.
- More bonus points: Is fully blueprintable (i.e. no cars/extra wagons)
Q: This is pointless, your buffer is too small!
A: That depends highly on the stack size of the target item and the unload balancing of the used design. For example with a stack size of 50 (e.g. vanilla ore) and perfectly balanced unloading you need a train every 6.48 seconds. While this might sound short this is quite achieveable for short and medium trains using high-speed signaling inside the unloading station combined with nuclear fuel. And for items with larger stack sizes the time frame increases linearly.
Q: You should use more trains instead!
A: Using more trains just shifts the problem to somewhere else. Rail networks are less prone to congestion with fewer trains and designing stations and junctions is also much easier and compact. In factorio you can always use a different approach, for example i could simply use one belt per wagon and change the factory accordingly, but that is not the goal of this experiment.
Q: How fast is a stack inserter?
A: A fully researched stack inserter can transfer 27.7i/s between two chests and 12.2i/s from chest to belt.
Q: I can unload two belts with just 6 inserters on each side!
A: No you can not. 6 inserterters can only unload 73.2 items per second, but two full belts need 80i/s.