Factorio Kovarex Without Combinators

Introduction & Motivation

This Guide describes a Kovarex enrichment design which uses a single Centrifuge to enrich U-238 into U-235, using just three circuit connections and without using combinators. Besides researching the Kovarex process itself, a minimum Inserter Capacity Bonus tech of Level 2 is required, to give a basic Inserter stack size of two and a Stack Inserter stack size of four.

The Kovarex enrichment process (unlocked with Purple Science) uses 40 U-235 (light green, rare) and five U-238 (dark green, common) in a 60-second Centrifuge craft, to output 41 U-235 and two U-238. The net change is three U-238 being converted to a single U-235. The products of the enrichment can then be fed back into the Centrifuge to be used for the next enrichment cycle.

Like all assemblers, the enrichment Centrifuge will load up with enough materials for a couple of crafting cycles. In this case, this will result in it keeping the U-235 it produces, meaning anything up to 80 U-235 could be sat in the Centrifuge, not being crafted into Fuel Cells, Nuclear Fuel or Atomic Bombs. To use our resources in the optimal manner, we need a way to avoid excess U-235 being fed into and/or accumulating in our Centrifuge, while also ensuring that a steady supply of U-238 is maintained. This is possible by counting the U-235 produced via Combinator wizardry, but a simpler method is possible, as shown in the next section.

Standard Version

The screenshot above shows the design in the Map Editor. When manually loaded with 40 U-235, U-238 will be taken from the inbound belt and the process started. Up to 10 extra U-238 will be stored in the Centrifuge, but this is okay, as U-238 is very common. At the end of the process, the products are removed via the Filter Inserters – U-235 is taken out by the top Stack Filter Inserter, and the two U-238 by the Filter Inserter on the right.

We can exploit the fact that one extra U-235 and two U-238 are always produced, by wiring the left and right-hand Filter Inserters to each other. The right-hand U-238 Inserter reads its hand contents (which will only ever be two U-238, set by a stack size override) in pulse mode, and sends the signal to the left. Hence, whenever a stack of two U-238 are removed at the end of the cycle, the left Filter Inserter will remove a single (via stack size override) newly-enriched U-235, and place it in the Passive Provider chest to be moved by bots to wherever it is needed.

In this way, U-235 produced will be extracted from the system, and with no U-235 input, an excess will never accumulate inside the Centrifuge. The Centrifuge does not run continuously as a result, but requires no further supervision or intervention from the player, as long as power and U-238 are supplied. The remaining 40 U-235, along with the two U-238, are fed back into the Centrifuge for the next cycle, via the top Stack and right Fast Inserter sets respectively.

Adding Productivity Modules

The Kovarex Centrifuge is an excellent candidate for the use of Productivity Modules – generating U-235 for free over time is a significant bonus! Unfortunately, this complicates the set-up as described thus far; with Productivity Modules, every so often there will be a cycle which generates 42 U-235 and not 41. In order to prevent these occasional “bonus” pieces from accumulating in our closed system, a second mechanism is needed to remove them.

This can be handled through the careful use of individual inserter stack sizes. The regular Stack Inserters are set such that they move exactly 40 U-235 in an integer number of swings – the possible stack sizes for this are 4, 5, 8 and 10. The Stack Filter inserter does not need a specific stack size. If a bonus piece of U-235 is generated, 41 pieces are removed via the Stack Filter inserter as quickly as possible (the left Filter Inserter will always take one) and placed in the first Steel Chest. The first Stack Inserter will then move up to four U-235 (or whichever possible stack size is chosen) at a time into the second Steel Chest. The second Stack Inserter is wired to this chest, and will only activate if a full stack is available to be moved; if exactly four U-235 are put in, four will be taken out and given back to the Centrifuge.

The result of all this is that any bonus U-235 piece will arrive by itself (a stack of 1), and so will not be moved by the Stack Inserter. Instead, it will be taken by the regular Inserter in the top-right, which is wired to only activate if a single U-235 is present. This is then placed in a second Passive Provider chest.

Beaconed Version

Using two Level 3 Productivity Modules reduces the Centrifuge’s crafting speed by 30% - the obvious solution to this is Speed Beacons. The use of Beacons is preferable to simply building more enrichment centrifuges, as each of these would require 40 U-235 to start the refining process – the very material we are short on!

This set-up can accommodate up to 12 Beacons, arranged as shown above. If all Beacons are fitted with two Speed Module 3s, a crafting speed of 6.7 is possible, with a power draw during crafting of around 10MW.

Final Remarks

While I solved the problem of removing crafted U-235 independently, I would like to acknowledge gGeorg on the Factorio forums for their insights into setting Inserter stack sizes to remove U-235 generated via Productivity bonuses, detailed in this thread[forums.factorio.com] .

Thank you for reading this guide - may your factories grow and prosper.

- SternguardJake

Source: https://steamcommunity.com/sharedfiles/filedetails/?id=2256102448

Kovarex Without Combinators

Introduction & Motivation

Standard Version

Adding Productivity Modules

Beaconed Version

Final Remarks

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