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[Experiment] Unloading 4 compressed blue belts per wagon.

Posted: Wed Mar 14, 2018 8:29 pm
by eradicator
Please keep the discussion focused on unloading 2 belts per wagon side. This is now a thought experiement, so please refrain from posting "i don't see the point". Also please read the FAQ at the end of this post.

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:
final.jpg
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final2.jpg
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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)
FAQ:
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.
Blueprint

Re: [Challenge?] Unloading 4 compressed blue belts per wagon.

Posted: Thu Mar 15, 2018 12:29 am
by timeshifter
So it's worth noting that just doing a dumb dump comes *really* close...

Image

But I did come up with two variations that both achieve perfect compression, depending on how much you value symmetry.

Image

Re: [Challenge?] Unloading 4 compressed blue belts per wagon.

Posted: Thu Mar 15, 2018 8:59 am
by DaveMcW
Here is a version with only 9 inserters after the buffer.
Blueprint
4_belt_wagon.jpg
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Re: [Challenge?] Unloading 4 compressed blue belts per wagon.

Posted: Thu Mar 15, 2018 4:13 pm
by aober93
Hmm yea ,but i dont get it. So you have 4 fillled blue belts. But the buffer chests for that 1 waggon will be empty just as the waggon leaves because the 12 stack inserters arent much faster. Leaving the belts blank again. Whats the benefit?

Re: [Challenge?] Unloading 4 compressed blue belts per wagon.

Posted: Thu Mar 15, 2018 5:02 pm
by timeshifter
The buffer chests fill up faster than can be dumped onto belts, so what this means is that as long as you can feed one of these designs trains at a rapid rate, each car can fully feed 4 lines of smelters with no other balancing required.

Re: [Challenge?] Unloading 4 compressed blue belts per wagon.

Posted: Thu Mar 15, 2018 5:25 pm
by eradicator
aober93 wrote:Hmm yea ,but i dont get it. So you have 4 fillled blue belts. But the buffer chests for that 1 waggon will be empty just as the waggon leaves because the 12 stack inserters arent much faster. Leaving the belts blank again. Whats the benefit?
Inserters are about 2.3 times faster when shovling from a wagon to a chest than when shovling from a chest onto a belt. Which means that as long as you have a train in the station about 50% of the time the belts should always be full. As i have trains waiting in a stacker the station won't ever be empty for more than 10 seconds.

Re: [Challenge?] Unloading 4 compressed blue belts per wagon.

Posted: Thu Mar 15, 2018 7:53 pm
by aober93
No i mean the belts are shoveling it aways almost as fast as the train unloads. The buffer chest is OK, but it'll hardly be filled. Given that a 4000item waggon is unloaded in under 25seconds, the waiting time for a new train is pretty significant and critical. Well if its 5 seconds it might work, but that train gotta be real fast accelerating and the station not be crowded. But then youll have ore trains with only 2000 items, that are unloaded faster than a new train arrives. :D

Re: [Challenge?] Unloading 4 compressed blue belts per wagon.

Posted: Thu Mar 15, 2018 8:42 pm
by eradicator
Hm. You're right i didn't do the math on that yet. The next ore train has 6.48 seconds to arrive and start unloading. I just measured my test train and it takes 8 seconds to arrive :/. So i'll have to add a second platform after all (which i wanted to avoid), that will give the next train 13 seconds time to start unloading. But ofc the whole point is moot then *sigh*. For shorter trains which can arrive fast enough it should still be pretty useful though.

Re: [Challenge?] Unloading 4 compressed blue belts per wagon.

Posted: Thu Mar 15, 2018 11:01 pm
by disentius
Here is an ugly one.
:mrgreen:
2belts 13.png
2belts 13.png (1.7 MiB) Viewed 8222 times
Unloading is not quite balanced, though
Blueprint

Re: [Challenge?] Unloading 4 compressed blue belts per wagon.

Posted: Sun Mar 18, 2018 2:34 am
by Saint
here a real simple version what i use, simple and good
ausladen.JPG
ausladen.JPG (90.5 KiB) Viewed 8128 times

Re: [Challenge?] Unloading 4 compressed blue belts per wagon.

Posted: Sun Mar 18, 2018 9:31 am
by eradicator
Saint wrote:here a real simple version what i use, simple and good
That's only two belts, not four though >_>'. This thread is explicitly about high-speed unloading.

Re: [Challenge?] Unloading 4 compressed blue belts per wagon.

Posted: Sun Mar 18, 2018 5:14 pm
by Saint
you see that you can go out with 4 lanes ?
i use only 2 lanes, but you can go out with 4 lanes without any problem

Re: [Challenge?] Unloading 4 compressed blue belts per wagon.

Posted: Sun Mar 18, 2018 8:52 pm
by eradicator
Saint wrote:you see that you can go out with 4 lanes ?
i use only 2 lanes, but you can go out with 4 lanes without any problem
No you can not. You only have 12 inserters which is insufficient for 4 full blue belts. Also as stated in the original topic i need 2 belts per side and not four belts on one side.

Re: [Challenge?] Unloading 4 compressed blue belts per wagon.

Posted: Wed Mar 21, 2018 11:04 pm
by Saint
12 is the max. what you can use for unload from the train.

if you use more as 12 inserter for filling the belts you need a good buffer.

why you want use more inserter to fill a belt as you can use to unload the train ?

if my english is to bad here in german
## Warum willst du mehr Inserter benutzen um das band zu füllen als du benutzen kannst um denn Zug auszuladen ?
## Das geht ja nur solange gut wie du mehr Material in den Kisten schon hasst als du ausladen tust, sprich wenn du nicht permanent alle Lanes brauchst damit sich was in der Kiste sammeln kann.
## Warum willst du eigentlich 4 blaue Bänder füllen obwohl es vom Durchsatz gar nicht ganz geht, zumindest nicht unter 100% Dauerlast ?

I have now just look short at the factorio wiki

https://wiki.factorio.com/Stack_inserter

Stack Inserter 744.8 items per minute
Blue Belt 2400 items per minute

2400 / 744,8 => 3,23 Stack inserter for fill a blue belt
eradicator wrote:
Saint wrote:you see that you can go out with 4 lanes ?
i use only 2 lanes, but you can go out with 4 lanes without any problem
No you can not. You only have 12 inserters which is insufficient for 4 full blue belts. Also as stated in the original topic i need 2 belts per side and not four belts on one side.
if you see the calculation, it can not work from the throughput to fill 4 blue belts

And yes i have all 2/4 belts on 1 side, i dont see that you need 2 on each side because i did not read the text complete, is see only all the picture

Re: [Challenge?] Unloading 4 compressed blue belts per wagon.

Posted: Thu Mar 22, 2018 12:42 am
by disentius
Look at the builds above again:)
throughput from stack inserter chest -> chest is much higher, you took the capacity from stack inserter to belt.
If you count the number of inserters which actually unload from chest to belt, you ll see why these contraptions work.

Re: [Challenge?] Unloading 4 compressed blue belts per wagon.

Posted: Thu Mar 22, 2018 12:07 pm
by eradicator
Saint wrote:And yes i have all 2/4 belts on 1 side, i dont see that you need 2 on each side because i did not read the text complete, is see only all the picture
I recommend you do read the text then (especially the link in the OP, which has the correct numbers for transfer speeds), as all your questions have already been answered in previous posts. Though on further thought the post about train timing is still too optimistic for some of the designs due to unbalanced unloading.

As for the "why do i want to do this" question... "because why not", it's factorio, we need more things faster :P. In the meantime i noticed that some of my calculations for my base design were off and i don't actually need 2 full belts (thanks to productivity), but it can still have it's uses for items with larger stack sizes than ore.

Also your english is fine.

Re: [Challenge?] Unloading 4 compressed blue belts per wagon.

Posted: Thu Mar 22, 2018 12:47 pm
by mrvn
The way to do this sensible is to use less belts per wagon and more train stations to maintain the total.

Using 2 blue belts per side simply empties the buffer chests too fast for the next train to arrive. So the belt won't be filled but have huge gaps.

Longer trains don't help that much as then they will be slower to accelerate and break and filling them from a single mine becomes that much harder. Driven to the extreme you will only fill one train from a mine before you have to build a new mine. What would be the point in that.

So the way to go is using multiple parallel stations. Simplest case put in 2 parallel stations. No you only need to fill 1 blue belt per side per wagon to get the same volume. Make it 4 stations and you only need to fill 1 red belt per side per wagon.

The amount of space you now need to fill 2 blue belts per side take way more space then adding a second parallel train stop and using a much simpler unloading design.

Re: [Experiment] Unloading 4 compressed blue belts per wagon.

Posted: Thu Mar 22, 2018 4:52 pm
by eradicator
@mrvn:
This thread is not supposed to be a generic "good factory design" thread. It is supposed to focus on the task of unloading 2 belts per side for those who might be interested. In order to prevent further derailing (haha :P) of the topic towards "but this is pointless!" i have edited the opening post and added an FAQ section which also addresses your question.

Regarding your "use more trains" idea: That does not work. If you e.g. use two trains with one belt per side each you now need to design a station to be able to constantly have two trains parked simultaeneously. Because if one of the stations is empty you lose one belt of throughput. The only gain you get is a slight increase in the time you need between two trains due to increased buffer sizes. But as you now also need twice as many trains and twice as many inserters+chests it is doubtful that you would gain much in terms of ease-of-throughput while significantly complicating your station. This is contrary to the point of making fewer stations by using high-speed unloading.

Re: [Experiment] Unloading 4 compressed blue belts per wagon.

Posted: Tue Mar 27, 2018 6:18 am
by ataaron
But can we reverse and load a wagon from 2 compressed blue belts without slowdown?

Re: [Experiment] Unloading 4 compressed blue belts per wagon.

Posted: Tue Mar 27, 2018 12:26 pm
by eradicator
ataaron wrote:But can we reverse and load a wagon from 2 compressed blue belts without slowdown?
The numbers are the same both ways. So all designs should work if you turn them around (except the ones that rely on sideloading obviously, which is most of them *cough*).