Barrels and Trains

[Bleda]

Hi guys

I'm having trouble carrying around the oil by train. I have one receiving station at my factory and several provider stations at remote oil fields. There are several trains running to these oil fields.

The problem I'm encountering is the following: The empty barrels have to get back to the provider stations. Now, I have to make sure, there are enough empty barrels for all the oil fields, but I also have to take care that the empy barrels don't get in the way of the filled barrels. If there is no space to unload empty barrels from the train, no full barrels can be inserted and therefore nothing moves anymore. Since you can't greenwire a train, you can't check how many barrels are in there.

How do you deal with this situation?

[Hazard]

Easiest solution is to run a 2 wagon system; one dedicated to empty barrels, and one dedicated to filled barrels, with seperate transfer lines at the stations.

It's rather far from optimal, I will admit.

[EstebanLB]

You plan it better, make two stations, one for unloading, and another one next to it for loading, do the same at the other area

[Zourin]

I do it the other way around. One train wagon per stop.

There is nothing wrong if you can't unload all the barrels. At each of the provider stops, just make sure you have a storage tank. A cargo wagon can hold 1200 oil. That's the same as a chem lab and tank combined (120 barrels each, if my maths are good)

At the refinery (reverse for the providers) have some smart inserters remove full barrels, others insert empty ones as space provides. If there isn't a full rotation, then either your oil system is backed up (in which case there's nothing wrong), or your inserter is bugged at the packing/unpacking site (in which case there's something wrong), or possibly you need another unpacking plant (which is hard to 'need' unless you're running 8+ refineries)

A little splitter load balancing and you're fine. Material backups aren't a problem. You can either increase your crude oil storage at the refinery, add another unpacking plant, or just let the spare oil ride until its needed. Old oil sites refil slowly, but with the tank, you can ensure that even if a fully empty. I don't suggest stockpiling barrels unless you have to, as it's space inefficient as far as chests go. The packing/unpacking process is only slowed by the refinery.

[ssilk]

The two wagons are the easiest IDE, the two station the most efficient.

We lack of something, which can give the logistic network info into another far away station.

But if you want to try:

- we have two stations: source and target
- target and source station (source is where the oil comes from) is fully driven by logistic bots in separated networks.
- the refinery is also a separated network!
- in the source: we connect all requester chests for empty barrels to the red network and pull the wire down, down, down
- not to the target station, but to the refinery and/or the barrel production.
- we program the inserters for the empty barrels on the belts to the target station so, that they will send empty barrels, when the requester chest on the source shows too less empty barrels.
- we need the same for the full barrels: when in the target train station the full barrels (from the source station) in the requester chests (that puts them on belts to the refinery) begin to go out, it's time to send new. We take the green wire for that.

Well that's it. This "flip flop" avoids overfilling of the train stations. I really hope that radio transfer of a network to any other point is possible at some time.


A well, another easy solution:
- if the number of the barrels are lower than the total storage for that barrels (full or empty) at one station, well, that will work, too.

[Darthlawsuit]

All we really want is this:



Minus the bad graffiti

[syneris]

Only create a specific amount of barrels, this is the most important part. This can be limited by the number of cargo containers you are using, but we'll get to that later.

Nothing special about the receiving station, just pull all filled barrels out and try to push empty barrels in. Make sure the receiving station has enough storage for every single barrel in the system in its loop. This is just a safety measure, as you could conceptually have much less.

There are multiple ways you could setup the provider stations, but this is easiest for me to explain. Allocate the barrels among your provider stations. Each station can get a different amount of barrels, just make sure it adds up to your total barrel count. This can also have a limit we'll cover later. Loading inserters can be whatever, but use smart inserters for unloading. Connect both red and green wires to the unloading smart inserters and both unloading and loading chests for each provider station, but don't wire the stations to each other. You can use the logistic condition if your network is local to the station and doesn't conflict with anywhere else. Using two conditions, set them to less than half that stations allocated barrel amount for both filled and empty barrels.

If there is an empty barrel, it is needed somewhere.

Now about the possible limits on barrel amounts. First know that a cargo container can currently hold 15 stacks. With barrels stacking to 8, that is 120 barrels per container. If you are using the same cargo container to hold both empty and filled barrels, each station is limited to twice the number of barrels that your train can hold. Also remember that filters aren't precise at large numbers, so this makes the station limited to 200 barrels per cargo container up to 10 long. This prevents a station from having more than half its barrels empty and being unable to unload empty barrels at at least one of your stations causing deadlock.

If your station needs more than 200 barrels per cargo container (max 10), switch to separate containers for empty and filled as it will not deadlock with this method.

The last this is that every train needs to stop at every station (or just use one train). This is much easier than trying to limit loading empty barrels on the right trains.