Are compressed belts really good?

[pieppiep]

Consider you have a factory with these parts connected with belts
- mining
- smelting
- electronic circuit production

Why would you want to have compressed belts between for example mining and smelting?
The compressed belt would be a sign you don't have enough smelting capacity.
When you increase smelting and the belt to electronic circuit production becomes compressed, it would mean you don't have enough electronic circuit production.

I think you should always try to not get compressed belts.
If a belt becomes compressed, the production it leads to isn't big enough or you need more belt capacity.

[DaveMcW]

Yes, if you are making up your factory as you go, compressed belts are a sign of a bottleneck.

However, compressing a belt gives about 20% more capacity than randomly inserting items! So in a well-designed factory it can be useful to support longer production lines.

[pieppiep]

Ah, so for example the smelting, build it so that the smelter line is short enough for the inserters to insert the items quickly, then make another line and combine/compress those two with a splitter?
But then again, if the output of the splitter is fully compressed you would still have a bottleneck.

So combining yes, but fully compressed still a no, you need more or faster belts.

[Zeblote]

Why would you want to have compressed belts between for example mining and smelting?
The compressed belt would be a sign you don't have enough smelting capacity.

Not necessarily, you're mistaking a compressed belt for a blocked one.

For example:



Fully compressed belt goes in, and is completely empty at the end.

[pieppiep]

But to make a compressed belt you have to block somewhere.
So this probably gives blocked mining drills or ore delivery stations.
To solve those blocked drills or stations you add more smelters and then you don't have full compressed belts anymore.

[Zeblote]

But to make a compressed belt you have to block somewhere.
So this probably gives blocked mining drills or ore delivery stations.
To solve those blocked drills or stations you add more smelters and then you don't have full compressed belts anymore.

There has to be a buffer somewhere to compress the belt (like at a train station), but then it's enough to mine exactly as much ore as your smelting can handle.
You just get more stuff transported on a single belt than you'd get without compressing it.

Though I have like 2-3 times as many miners as I need because moving them is boring and I don't want to have to do it all the time.

[bobucles]

Compressed belts are more of an ADHD point of pride than anything else. A fully compressed belt getting fully used means you have just the right amount of factory.

[ratchetfreak]

Compressed belts are more of an ADHD point of pride than anything else. A fully compressed belt getting fully used means you have just the right amount of factory.

I think you mean OCD, ADHD won't have the persistent focus needed to... hey look a butterfly

[Tnarg]

In growing factory compressed belts are useful. Unless you know a head of time the perfect ratios compressed belts tell you what is not your limiting factor. Also I try to always have my ore run in on compressed belts it's when it stops being compressed it time to look for a new mining site.

[HanziQ]

Compressed belts are more of an ADHD point of pride than anything else. A fully compressed belt getting fully used means you have just the right amount of factory.

I think you mean OCD, ADHD won't have the persistent focus needed to... hey look a butterfly

I think you mean OCPD. I don't think people with acual OCD are even playing Factorio, it just might be too much.

[Shokubai]

Consider you have a factory with these parts connected with belts
- mining
- smelting
- electronic circuit production

Why would you want to have compressed belts between for example mining and smelting?
The compressed belt would be a sign you don't have enough smelting capacity.
When you increase smelting and the belt to electronic circuit production becomes compressed, it would mean you don't have enough electronic circuit production.

I think you should always try to not get compressed belts.
If a belt becomes compressed, the production it leads to isn't big enough or you need more belt capacity.

You are really getting into Push/Pull Logistics and there are merits and draw backs to both. I will try and relate this in Factorio terms as best I can.

PUSH

With a push-based supply chain, products are pushed through the channel, from the production side up to the retailer. The manufacturer sets production at a level in accord with historical ordering patterns from retailers. It takes longer for a push-based supply chain to respond to changes in demand, which can result in overstocking or bottlenecks and delays (the bullwhip effect), unacceptable service levels and product obsolescence.

In your example you are PUSHING materials up the chain. You forcast what your factory will use at the mining level and grow your factory upwards from that point. The result will be that you either forcast high (compressed belts) or you forcast low (shortages).

PULL

In a pull-based supply chain, procurement, production and distribution are demand-driven rather than to forecast. However, a pull strategy does not always require make-to-order production. Toyota Motors Manufacturing is frequently used as an example of pull production, yet do not typically produce to order. They follow the "supermarket model" where limited inventory is kept on hand and is replenished as it is consumed. In Toyota's case, Kanban cards are used to signal the need to replenish inventory.

In this case you might assume that you are planning from the Manufacturing end of things. I need 40u/m Sci pack 3 to feed 10 Science factories. Working backwords you plan your Smart Inserters, Steel, Green and Red Science, and Batteries. ...And so on down to Mining.
Pull Logistics works more practically when thinking about Logi Bots. Picture a Chest with a smart inserter set to <2000 Green Circuits. Every time a green circuit is used a new one is created.

[BlakeMW]

Compressed belts are great for making maximum use of very expensive investments, like a green circuit assembler setting using prod3 modules and speed beacons. When you've invested so many resources into something you don't want it sitting idle waiting for resources.

[ratchetfreak]

Compressed belts are great for making maximum use of very expensive investments, like a green circuit assembler setting using prod3 modules and speed beacons. When you've invested so many resources into something you don't want it sitting idle waiting for resources.

Or you can just add another lane of belt because 4 nearly compressed belts bring more than 3 fully compressed belts

[Zeblote]

Compressed belts are great for making maximum use of very expensive investments, like a green circuit assembler setting using prod3 modules and speed beacons. When you've invested so many resources into something you don't want it sitting idle waiting for resources.

Or you can just add another lane of belt because 4 nearly compressed belts bring more than 3 fully compressed belts

But that doesn't look as neat and splitting something off of 2 belts is harder than of 1.

[ssilk]

Full belts can be seen as unaccessable storage!
This is good and bad. First numbers: An item is 0.28x0.28 tiles, so 10 items take 2.8 belts. Or one belt can hold 3,571428571 items per lane or 7,142857142 on one tile. Let's say 7. So 10 belts can be seen as a storage of 70 items. Let's say the distance from the mining site to the smelters is 100 tiles, then it stores up to 700 items.

So in the early game this is very good. Nothing is more easy to read than a belt: You can see immediately, if there is enough backlog. If the backlog begins to shrink, it's time to build more mines.

In the end game this is vice versa! Items get more and more expensive:

Code: Select all

item-cost = sum( crafting time of all items needed to craft this item ) + crafting time of this item 

And logically you need to take care of the "hidden storage" of belts. Big fail for example: Put modules on long belts.

And take in account: The items on a stocked belt cannot be used for anything.

So this means, that for the cheap items (ores, plates...) a high compression is normally good, cause it enables you to see bottlenecks much earlier. This can also be seen as PUSH-based (see above), but instead of estimating how much you need to build (which is in my eyes quite complicated) you just look, how much you need to fill the belts.

This changes to PULL based for the expensive items. Suddenly it is important not to overproduce. And that means in my eyes to use bots instead of belts, cause the "hidden storage" of bots is much, much lower, than belts.

Is belt compression good?
I have a rule, which explains exactly, when you are at full speed or you have a bottleneck:

- If there is full compression, but no sticking: Everything is fine.
- If there is full compression, but sticking: Search for a point, where the full compression suddenly is lost. That exactly is the point of the bottleneck.

[siggboy]

But to make a compressed belt you have to block somewhere.

No.

All you have to do is put more items per second on the belt than the belt can carry. The thing that "blocks" is the belt itself.

For example, put 2x5 fast inserters along a blue belt and have them fill the belt from chests. Do it again with a second blue belt. Merge the two belts with an express splitter.

The result is a fully compressed blue belt, even if you put a line of 30 fast inserters right behind it that will remove the items from the belt (i.e. no blocking, full demand).

Of course it's not possible to create a compressed belt with inserters alone (unless something "blocks", which is what you're thinking of).

[ssilk]

Since v0.12 fully compressed belts are only possible with joining splitters.

[Zeblote]

Since v0.12 fully compressed belts are only possible with joining splitters.

Before 0.12 compressed belts weren't really possible at all, so yeah.

[Peppe]

Since v0.12 fully compressed belts are only possible with joining splitters.

I thought underground belts accept input/compress belt when a plain belt normally would not -- not sure if it reaches "full" compression.

[BlakeMW]

I thought underground belts accept input/compress belt when a plain belt normally would not -- not sure if it reaches "full" compression.

This is correct. Underground belts can fully compress since when an item is inserted into an underground belt it only requires there be free space in the underground belt "buffer", it doesn't do any check for a long enough gap on a belt.